From: Stefan Berger <stefanb@linux.vnet.ibm.com>
The TPM Physical Presence interface consists of an ACPI part, a shared
memory part, and code in the firmware. Users can send messages to the
firmware by writing a code into the shared memory through invoking the
ACPI code. When a reboot happens, the firmware looks for the code and
acts on it by sending sequences of commands to the TPM.
This patch adds the ACPI code. It is similar to the one in EDK2 but doesn't
assume that SMIs are necessary to use. It uses a similar datastructure for
the shared memory as EDK2 does so that EDK2 and SeaBIOS could both make use
of it. I extended the shared memory data structure with an array of 256
bytes, one for each code that could be implemented. The array contains
flags describing the individual codes. This decouples the ACPI implementation
from the firmware implementation.
The underlying TCG specification is accessible from the following page.
https://trustedcomputinggroup.org/tcg-physical-presence-interface-specification/
This patch implements version 1.30.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
---
v6:
- more code documentation (Marc-André)
- use some explicit named variables to ease reading (Marc-André)
- use fixed size fields/memory regions, remove PPI struct (Marc-André)
- only add PPI ACPI methods if PPI is enabled (Marc-André)
- document the qemu/firmware ACPI memory region (Stefan)
v5 (Marc-André):
- /struct tpm_ppi/struct TPMPPIData
v4 (Marc-André):
- replace 'DerefOf (FUNC [N])' with a function, to fix Windows ACPI
handling.
- replace 'return Package (..) {} ' with scoped variables, to fix
Windows ACPI handling.
v3:
- add support for PPI to CRB
- split up OperationRegion TPPI into two parts, one containing
the registers (TPP1) and the other one the flags (TPP2); switched
the order of the flags versus registers in the code
- adapted ACPI code to small changes to the array of flags where
previous flag 0 was removed and now shifting right wasn't always
necessary anymore
v2:
- get rid of FAIL variable; function 5 was using it and always
returns 0; the value is related to the ACPI function call not
a possible failure of the TPM function call.
- extend shared memory data structure with per-opcode entries
holding flags and use those flags to determine what to return
to caller
- implement interface version 1.3
---
include/hw/acpi/tpm.h | 8 +
hw/i386/acpi-build.c | 423 +++++++++++++++++++++++++++++++++++++++++-
docs/specs/tpm.txt | 79 ++++++++
3 files changed, 509 insertions(+), 1 deletion(-)
diff --git a/include/hw/acpi/tpm.h b/include/hw/acpi/tpm.h
index f79d68a77a..e0bd07862e 100644
--- a/include/hw/acpi/tpm.h
+++ b/include/hw/acpi/tpm.h
@@ -196,4 +196,12 @@ REG32(CRB_DATA_BUFFER, 0x80)
#define TPM_PPI_VERSION_NONE 0
#define TPM_PPI_VERSION_1_30 1
+/* whether function is blocked by BIOS settings; bits 0, 1, 2 */
+#define TPM_PPI_FUNC_NOT_IMPLEMENTED (0 << 0)
+#define TPM_PPI_FUNC_BIOS_ONLY (1 << 0)
+#define TPM_PPI_FUNC_BLOCKED (2 << 0)
+#define TPM_PPI_FUNC_ALLOWED_USR_REQ (3 << 0)
+#define TPM_PPI_FUNC_ALLOWED_USR_NOT_REQ (4 << 0)
+#define TPM_PPI_FUNC_MASK (7 << 0)
+
#endif /* HW_ACPI_TPM_H */
diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index d9320845ed..d815af4eef 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -43,6 +43,7 @@
#include "hw/acpi/memory_hotplug.h"
#include "sysemu/tpm.h"
#include "hw/acpi/tpm.h"
+#include "hw/tpm/tpm_ppi.h"
#include "hw/acpi/vmgenid.h"
#include "sysemu/tpm_backend.h"
#include "hw/timer/mc146818rtc_regs.h"
@@ -1789,6 +1790,421 @@ static Aml *build_q35_osc_method(void)
return method;
}
+static void
+build_tpm_ppi(Aml *dev)
+{
+ Aml *method, *name, *field, *ifctx, *ifctx2, *ifctx3, *pak;
+ int i;
+
+ if (!object_property_get_bool(OBJECT(tpm_find()), "ppi", &error_abort)) {
+ return;
+ }
+ /*
+ * TPP1 is for the flags that indicate which PPI operations
+ * are supported by the firmware. The firmware is expected to
+ * write these flags.
+ */
+ aml_append(dev,
+ aml_operation_region("TPP1", AML_SYSTEM_MEMORY,
+ aml_int(TPM_PPI_ADDR_BASE), 0x100));
+ field = aml_field("TPP1", AML_ANY_ACC, AML_NOLOCK, AML_PRESERVE);
+ for (i = 0; i < 0x100; i++) {
+ char *tmp = g_strdup_printf("FN%02X", i);
+ aml_append(field, aml_named_field(tmp, 8));
+ g_free(tmp);
+ }
+ aml_append(dev, field);
+
+ /*
+ * TPP2 is for the registers that ACPI code used to pass
+ * the PPI code and parameter (PPRQ, PPRM) to the firmware.
+ */
+ aml_append(dev,
+ aml_operation_region("TPP2", AML_SYSTEM_MEMORY,
+ aml_int(TPM_PPI_ADDR_BASE + 0x100),
+ 0x5A));
+ field = aml_field("TPP2", AML_ANY_ACC, AML_NOLOCK, AML_PRESERVE);
+ aml_append(field, aml_named_field("PPIN", 8));
+ aml_append(field, aml_named_field("PPIP", 32));
+ aml_append(field, aml_named_field("PPRP", 32));
+ aml_append(field, aml_named_field("PPRQ", 32));
+ aml_append(field, aml_named_field("PPRM", 32));
+ aml_append(field, aml_named_field("LPPR", 32));
+ aml_append(dev, field);
+
+ /*
+ * A function to return the value of DerefOf (FUNC [N]), by using
+ * accessing the fields individually instead. This is a workaround
+ * for what looks like a Windows ACPI bug in all versions so far
+ * (fwiw, DerefOf (FUNC [N]) works on Linux).
+ */
+ method = aml_method("TPFN", 1, AML_SERIALIZED);
+ {
+ for (i = 0; i < 0x100; i++) {
+ ifctx = aml_if(aml_equal(aml_int(i), aml_arg(0)));
+ {
+ aml_append(ifctx, aml_return(aml_name("FN%02X", i)));
+ }
+ aml_append(method, ifctx);
+ }
+ aml_append(method, aml_return(aml_int(0)));
+ }
+ aml_append(dev, method);
+
+ pak = aml_package(2);
+ aml_append(pak, aml_int(0));
+ aml_append(pak, aml_int(0));
+ name = aml_name_decl("TPM2", pak);
+ aml_append(dev, name);
+
+ pak = aml_package(3);
+ aml_append(pak, aml_int(0));
+ aml_append(pak, aml_int(0));
+ aml_append(pak, aml_int(0));
+ name = aml_name_decl("TPM3", pak);
+ aml_append(dev, name);
+
+ method = aml_method("_DSM", 4, AML_SERIALIZED);
+ {
+ uint8_t zerobyte[1] = { 0 };
+ Aml *func_idx, *rev, *op, *op_arg, *op_flags;
+
+ ifctx = aml_if(
+ aml_equal(aml_arg(0),
+ aml_touuid("3DDDFAA6-361B-4EB4-A424-8D10089D1653")));
+ {
+ func_idx = aml_local(0);
+ aml_append(ifctx,
+ aml_store(aml_to_integer(aml_arg(2)), func_idx));
+
+ /* standard DSM query function */
+ func_idx = aml_local(0);
+ ifctx2 = aml_if(aml_equal(func_idx, aml_int(0)));
+ {
+ uint8_t byte_list[2] = { 0xff, 0x01 };
+ aml_append(ifctx2, aml_return(aml_buffer(2, byte_list)));
+ }
+ aml_append(ifctx, ifctx2);
+
+ /*
+ * 8.1.1 Get Physical Presence Interface Version
+ *
+ * Arg 2 (Integer): Function Index = 1
+ * Arg 3 (Package): Arguments = Empty Package
+ * Returns: Type: String
+ */
+ func_idx = aml_local(0);
+ ifctx2 = aml_if(aml_equal(func_idx, aml_int(1)));
+ {
+ aml_append(ifctx2, aml_return(aml_string("1.3")));
+ }
+ aml_append(ifctx, ifctx2);
+
+ /*
+ * 8.1.2 Submit TPM Operation Request to Pre-OS Environment
+ *
+ * Arg 2 (Integer): Function Index = 2
+ * Arg 3 (Package): Arguments = Package: Type: Integer
+ * Operation Value of the Request
+ * Returns: Type: Integer
+ * 0: Success
+ * 1: Operation Value of the Request Not Supported
+ * 2: General Failure
+ */
+ func_idx = aml_local(0);
+ ifctx2 = aml_if(aml_equal(func_idx, aml_int(2)));
+ {
+ /* get opcode */
+ op = aml_derefof(aml_index(aml_arg(3), aml_int(0)));
+ aml_append(ifctx2, aml_store(op, aml_local(0)));
+
+ /* get opcode flags */
+ op = aml_local(0);
+ aml_append(ifctx2,
+ aml_store(aml_call1("TPFN", op), aml_local(1)));
+
+ op_flags = aml_local(1);
+ /* if func[opcode] & TPM_PPI_FUNC_NOT_IMPLEMENTED */
+ ifctx3 = aml_if(
+ aml_equal(
+ aml_and(op_flags, aml_int(TPM_PPI_FUNC_MASK), NULL),
+ aml_int(TPM_PPI_FUNC_NOT_IMPLEMENTED)));
+ {
+ /* 1: not implemented */
+ aml_append(ifctx3, aml_return(aml_int(1)));
+ }
+ aml_append(ifctx2, ifctx3);
+
+ op = aml_local(0);
+ aml_append(ifctx2, aml_store(op, aml_name("PPRQ")));
+ aml_append(ifctx2, aml_store(aml_int(0), aml_name("PPRM")));
+ /* 0: success */
+ aml_append(ifctx2, aml_return(aml_int(0)));
+ }
+ aml_append(ifctx, ifctx2);
+
+ /*
+ * 8.1.3 Get Pending TPM Operation Requested By the OS
+ *
+ * Arg 2 (Integer): Function Index = 3
+ * Arg 3 (Package): Arguments = Empty Package
+ * Returns: Type: Package of Integers
+ * Integer 1: Function Return code
+ * 0: Success
+ * 1: General Failure
+ * Integer 2: Pending operation requested by the OS
+ * 0: None
+ * >0: Operation Value of the Pending Request
+ * Integer 3: Optional argument to pending operation
+ * requested by the OS
+ * 0: None
+ * >0: Argument Value of the Pending Request
+ */
+ func_idx = aml_local(0);
+ ifctx2 = aml_if(aml_equal(func_idx, aml_int(3)));
+ {
+ /* revision to integer */
+ aml_append(ifctx2,
+ aml_store(
+ aml_to_integer(aml_arg(1)),
+ aml_local(1)));
+ /*
+ * Revision ID of 1, no integer parameter beyond
+ * parameter two are expected
+ */
+ rev = aml_local(1);
+ ifctx3 = aml_if(aml_equal(rev, aml_int(1)));
+ {
+ /* TPM2[1] = PPRQ */
+ aml_append(ifctx3,
+ aml_store(
+ aml_name("PPRQ"),
+ aml_index(aml_name("TPM2"), aml_int(1))));
+ aml_append(ifctx3, aml_return(aml_name("TPM2")));
+ }
+ aml_append(ifctx2, ifctx3);
+
+ /*
+ * A return value of {0, 23, 1} indicates that
+ * operation 23 with argument 1 is pending.
+ */
+ rev = aml_local(1);
+ ifctx3 = aml_if(aml_equal(rev, aml_int(2)));
+ {
+ /* TPM3[1] = PPRQ */
+ aml_append(ifctx3,
+ aml_store(
+ aml_name("PPRQ"),
+ aml_index(aml_name("TPM3"), aml_int(1))));
+ /* TPM3[2] = PPRM */
+ aml_append(ifctx3,
+ aml_store(
+ aml_name("PPRM"),
+ aml_index(aml_name("TPM3"), aml_int(2))));
+ aml_append(ifctx3, aml_return(aml_name("TPM3")));
+ }
+ aml_append(ifctx2, ifctx3);
+ }
+ aml_append(ifctx, ifctx2);
+
+ /*
+ * 8.1.4 Get Platform-Specific Action to Transition to
+ * Pre-OS Environment
+ *
+ * Arg 2 (Integer): Function Index = 4
+ * Arg 3 (Package): Arguments = Empty Package
+ * Returns: Type: Integer
+ * 0: None
+ * 1: Shutdown
+ * 2: Reboot
+ * 3: OS Vendor-specific
+ */
+ func_idx = aml_local(0);
+ ifctx2 = aml_if(aml_equal(func_idx, aml_int(4)));
+ {
+ /* reboot */
+ aml_append(ifctx2, aml_return(aml_int(2)));
+ }
+ aml_append(ifctx, ifctx2);
+
+ /*
+ * 8.1.5 Return TPM Operation Response to OS Environment
+ *
+ * Arg 2 (Integer): Function Index = 5
+ * Arg 3 (Package): Arguments = Empty Package
+ * Returns: Type: Package of Integer
+ * Integer 1: Function Return code
+ * 0: Success
+ * 1: General Failure
+ * Integer 2: Most recent operation request
+ * 0: None
+ * >0: Operation Value of the most recent request
+ * Integer 3: Response to the most recent operation request
+ * 0: Success
+ * 0x00000001..0x00000FFF: Corresponding TPM
+ * error code
+ * 0xFFFFFFF0: User Abort or timeout of dialog
+ * 0xFFFFFFF1: firmware Failure
+ */
+ func_idx = aml_local(0);
+ ifctx2 = aml_if(aml_equal(func_idx, aml_int(5)));
+ {
+ /* TPM3[1] = LPPR */
+ aml_append(ifctx2,
+ aml_store(
+ aml_name("LPPR"),
+ aml_index(aml_name("TPM3"), aml_int(1))));
+ /* TPM3[2] = PPRP */
+ aml_append(ifctx2,
+ aml_store(
+ aml_name("PPRP"),
+ aml_index(aml_name("TPM3"), aml_int(2))));
+ aml_append(ifctx2, aml_return(aml_name("TPM3")));
+ }
+ aml_append(ifctx, ifctx2);
+
+ /*
+ * 8.1.6 Submit preferred user language
+ *
+ * Arg 2 (Integer): Function Index = 6
+ * Arg 3 (Package): Arguments = String Package
+ * Preferred language code
+ * Returns: Type: Integer
+ * Function Return Code
+ * 3: Not implemented
+ */
+ func_idx = aml_local(0);
+ ifctx2 = aml_if(aml_equal(func_idx, aml_int(6)));
+ {
+ /* 3 = not implemented */
+ aml_append(ifctx2, aml_return(aml_int(3)));
+ }
+ aml_append(ifctx, ifctx2);
+
+ /*
+ * 8.1.7 Submit TPM Operation Request to Pre-OS Environment 2
+ *
+ * Arg 2 (Integer): Function Index = 7
+ * Arg 3 (Package): Arguments = Package: Type: Integer
+ * Integer 1: Operation Value of the Request
+ * Integer 2: Argument for Operation (optional)
+ * Returns: Type: Integer
+ * 0: Success
+ * 1: Not Implemented
+ * 2: General Failure
+ * 3: Operation blocked by current firmware settings
+ */
+ func_idx = aml_local(0);
+ ifctx2 = aml_if(aml_equal(func_idx, aml_int(7)));
+ {
+ /* get opcode */
+ op = aml_derefof(aml_index(aml_arg(3), aml_int(0)));
+ aml_append(ifctx2, aml_store(op, aml_local(0)));
+
+ /* get opcode flags */
+ op = aml_local(0);
+ aml_append(ifctx2, aml_store(aml_call1("TPFN", op),
+ aml_local(1)));
+ /* if func[opcode] & TPM_PPI_FUNC_NOT_IMPLEMENTED */
+ op_flags = aml_local(1);
+ ifctx3 = aml_if(
+ aml_equal(
+ aml_and(op_flags, aml_int(TPM_PPI_FUNC_MASK), NULL),
+ aml_int(TPM_PPI_FUNC_NOT_IMPLEMENTED)));
+ {
+ /* 1: not implemented */
+ aml_append(ifctx3, aml_return(aml_int(1)));
+ }
+ aml_append(ifctx2, ifctx3);
+
+ /* if func[opcode] & TPM_PPI_FUNC_BLOCKED */
+ op_flags = aml_local(1);
+ ifctx3 = aml_if(
+ aml_equal(
+ aml_and(op_flags, aml_int(TPM_PPI_FUNC_MASK), NULL),
+ aml_int(TPM_PPI_FUNC_BLOCKED)));
+ {
+ /* 3: blocked by firmware */
+ aml_append(ifctx3, aml_return(aml_int(3)));
+ }
+ aml_append(ifctx2, ifctx3);
+
+ /* revision to integer */
+ aml_append(ifctx2,
+ aml_store(
+ aml_to_integer(aml_arg(1)),
+ aml_local(1)));
+
+ rev = aml_local(1);
+ ifctx3 = aml_if(aml_equal(rev, aml_int(1)));
+ {
+ /* revision 1 */
+ /* PPRQ = op */
+ op = aml_local(0);
+ aml_append(ifctx3, aml_store(op, aml_name("PPRQ")));
+ /* no argument, PPRM = 0 */
+ aml_append(ifctx3, aml_store(aml_int(0),
+ aml_name("PPRM")));
+ }
+ aml_append(ifctx2, ifctx3);
+
+ rev = aml_local(1);
+ ifctx3 = aml_if(aml_equal(rev, aml_int(2)));
+ {
+ /* revision 2 */
+ /* PPRQ = op */
+ op = aml_local(0);
+ op_arg = aml_derefof(aml_index(aml_arg(3), aml_int(1)));
+ aml_append(ifctx3, aml_store(op, aml_name("PPRQ")));
+ /* PPRM = arg3[1] */
+ aml_append(ifctx3, aml_store(op_arg, aml_name("PPRM")));
+ }
+ aml_append(ifctx2, ifctx3);
+ /* 0: success */
+ aml_append(ifctx2, aml_return(aml_int(0)));
+ }
+ aml_append(ifctx, ifctx2);
+
+ /*
+ * 8.1.8 Get User Confirmation Status for Operation
+ *
+ * Arg 2 (Integer): Function Index = 8
+ * Arg 3 (Package): Arguments = Package: Type: Integer
+ * Operation Value that may need user confirmation
+ * Returns: Type: Integer
+ * 0: Not implemented
+ * 1: Firmware only
+ * 2: Blocked for OS by firmware configuration
+ * 3: Allowed and physically present user required
+ * 4: Allowed and physically present user not required
+ */
+ func_idx = aml_local(0);
+ ifctx2 = aml_if(aml_equal(func_idx, aml_int(8)));
+ {
+ /* get opcode */
+ op = aml_derefof(aml_index(aml_arg(3), aml_int(0)));
+ aml_append(ifctx2, aml_store(op, aml_local(0)));
+
+ /* get opcode flags */
+ op = aml_local(0);
+ aml_append(ifctx2, aml_store(aml_call1("TPFN", op),
+ aml_local(1)));
+ op_flags = aml_local(1);
+ /* return confirmation status code */
+ aml_append(ifctx2,
+ aml_return(
+ aml_and(op_flags,
+ aml_int(TPM_PPI_FUNC_MASK), NULL)));
+ }
+ aml_append(ifctx, ifctx2);
+
+ aml_append(ifctx, aml_return(aml_buffer(1, zerobyte)));
+ }
+ aml_append(method, ifctx);
+ }
+ aml_append(dev, method);
+}
+
static void
build_dsdt(GArray *table_data, BIOSLinker *linker,
AcpiPmInfo *pm, AcpiMiscInfo *misc,
@@ -2153,6 +2569,9 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
*/
/* aml_append(crs, aml_irq_no_flags(TPM_TIS_IRQ)); */
aml_append(dev, aml_name_decl("_CRS", crs));
+
+ build_tpm_ppi(dev);
+
aml_append(scope, dev);
}
@@ -2172,6 +2591,8 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
aml_append(method, aml_return(aml_int(0x0f)));
aml_append(dev, method);
+ build_tpm_ppi(dev);
+
aml_append(sb_scope, dev);
}
@@ -2920,7 +3341,7 @@ void acpi_setup(void)
tpm_config = (FWCfgTPMConfig) {
.tpmppi_address = cpu_to_le32(TPM_PPI_ADDR_BASE),
.tpm_version = cpu_to_le32(tpm_get_version(tpm_find())),
- .tpmppi_version = cpu_to_le32(TPM_PPI_VERSION_NONE)
+ .tpmppi_version = cpu_to_le32(TPM_PPI_VERSION_1_30)
};
fw_cfg_add_file(pcms->fw_cfg, "etc/tpm/config",
&tpm_config, sizeof tpm_config);
diff --git a/docs/specs/tpm.txt b/docs/specs/tpm.txt
index 2ddb768084..c27762c723 100644
--- a/docs/specs/tpm.txt
+++ b/docs/specs/tpm.txt
@@ -62,6 +62,85 @@ URL:
https://trustedcomputinggroup.org/tcg-acpi-specification/
+== ACPI PPI Interface ==
+
+QEMU supports the Physical Presence Interface (PPI) for TPM 1.2 and TPM 2. This
+interface requires ACPI and firmware support. The specification can be found at
+the following URL:
+
+https://trustedcomputinggroup.org/resource/tcg-physical-presence-interface-specification/
+
+PPI enables a system administrator (root) to request a modification to the
+TPM upon reboot. The PPI specification defines the operation requests and the
+actions the firmware has to take. The system administrator passes the operation
+request number to the firmware through an ACPI interface which writes this
+number to a memory location that the firmware knows. Upon reboot, the firmware
+finds the number and sends commands to the the TPM. The firmware writes the TPM
+result code and the operation request number to a memory location that ACPI can
+read from and pass the result on to the administrator.
+
+The PPI specification defines a set of mandatory and optional operations for
+the firmware to implement. The ACPI interface also allows an administrator to
+list the supported operations. In QEMU the ACPI code is generated by QEMU, yet
+the firmware needs to implement support on a per-operations basis, and
+different firmwares may support a different subset. Therefore, QEMU introduces
+the virtual memory device for PPI where the firmware can indicate which
+operations it supports and ACPI can enable the ones that are supported and
+disable all others. This interface lies in main memory and has the following
+layout:
+
+ +----------+--------+--------+-------------------------------------------+
+ | Field | Length | Offset | Description |
+ +----------+--------+--------+-------------------------------------------+
+ | func | 0x100 | 0x000 | Firmware sets values for each supported |
+ | | | | operation. See defined values below. |
+ +----------+--------+--------+-------------------------------------------+
+ | ppin | 0x1 | 0x100 | SMI interrupt to use. Set by firmware. |
+ | | | | Not supported. |
+ +----------+--------+--------+-------------------------------------------+
+ | ppip | 0x4 | 0x101 | ACPI function index to pass to SMM code. |
+ | | | | Set by ACPI. Not supported. |
+ +----------+--------+--------+-------------------------------------------+
+ | pprp | 0x4 | 0x105 | Result of last executed operation. Set by |
+ | | | | firmware. See function index 5 for values.|
+ +----------+--------+--------+-------------------------------------------+
+ | pprq | 0x4 | 0x109 | Operation request number to execute. See |
+ | | | | 'Physical Presence Interface Operation |
+ | | | | Summary' tables in specs. Set by ACPI. |
+ +----------+--------+--------+-------------------------------------------+
+ | pprm | 0x4 | 0x10d | Operation request optional parameter. |
+ | | | | Values depend on operation. Set by ACPI. |
+ +----------+--------+--------+-------------------------------------------+
+ | lppr | 0x4 | 0x111 | Last executed operation request number. |
+ | | | | Copied from pprq field by firmware. |
+ +----------+--------+--------+-------------------------------------------+
+ | fret | 0x4 | 0x115 | Result code from SMM function. |
+ | | | | Not supported. |
+ +----------+--------+--------+-------------------------------------------+
+ | res1 | 0x40 | 0x119 | Reserved for future use |
+ +----------+--------+--------+-------------------------------------------+
+ | next_step| 0x1 | 0x159 | Operation to execute after reboot by |
+ | | | | firmware. Used by firmware. |
+ +----------+--------+--------+-------------------------------------------+
+
+ The following values are supported for the 'func' field. They correspond
+ to the values used by ACPI function index 8.
+
+ +----------+-------------------------------------------------------------+
+ | value | Description |
+ +----------+-------------------------------------------------------------+
+ | 0 | Operation is not implemented. |
+ +----------+-------------------------------------------------------------+
+ | 1 | Operation is only accessible through firmware. |
+ +----------+-------------------------------------------------------------+
+ | 2 | Operation is blocked for OS by firmware configuration. |
+ +----------+-------------------------------------------------------------+
+ | 3 | Operation is allowed and physically present user required. |
+ +----------+-------------------------------------------------------------+
+ | 4 | Operation is allowed and physically present user is not |
+ | | required. |
+ +----------+-------------------------------------------------------------+
+
QEMU files related to TPM ACPI tables:
- hw/i386/acpi-build.c
--
2.18.0.rc1
On Tue, Jun 26, 2018 at 02:23:43PM +0200, Marc-André Lureau wrote:
> From: Stefan Berger <stefanb@linux.vnet.ibm.com>
>
> The TPM Physical Presence interface consists of an ACPI part, a shared
> memory part, and code in the firmware. Users can send messages to the
> firmware by writing a code into the shared memory through invoking the
> ACPI code. When a reboot happens, the firmware looks for the code and
> acts on it by sending sequences of commands to the TPM.
>
> This patch adds the ACPI code. It is similar to the one in EDK2 but doesn't
> assume that SMIs are necessary to use. It uses a similar datastructure for
> the shared memory as EDK2 does so that EDK2 and SeaBIOS could both make use
> of it. I extended the shared memory data structure with an array of 256
> bytes, one for each code that could be implemented. The array contains
> flags describing the individual codes. This decouples the ACPI implementation
> from the firmware implementation.
>
> The underlying TCG specification is accessible from the following page.
>
> https://trustedcomputinggroup.org/tcg-physical-presence-interface-specification/
>
> This patch implements version 1.30.
>
> Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
>
> ---
>
> v6:
> - more code documentation (Marc-André)
> - use some explicit named variables to ease reading (Marc-André)
> - use fixed size fields/memory regions, remove PPI struct (Marc-André)
> - only add PPI ACPI methods if PPI is enabled (Marc-André)
> - document the qemu/firmware ACPI memory region (Stefan)
>
> v5 (Marc-André):
> - /struct tpm_ppi/struct TPMPPIData
>
> v4 (Marc-André):
> - replace 'DerefOf (FUNC [N])' with a function, to fix Windows ACPI
> handling.
> - replace 'return Package (..) {} ' with scoped variables, to fix
> Windows ACPI handling.
>
> v3:
> - add support for PPI to CRB
> - split up OperationRegion TPPI into two parts, one containing
> the registers (TPP1) and the other one the flags (TPP2); switched
> the order of the flags versus registers in the code
> - adapted ACPI code to small changes to the array of flags where
> previous flag 0 was removed and now shifting right wasn't always
> necessary anymore
>
> v2:
> - get rid of FAIL variable; function 5 was using it and always
> returns 0; the value is related to the ACPI function call not
> a possible failure of the TPM function call.
> - extend shared memory data structure with per-opcode entries
> holding flags and use those flags to determine what to return
> to caller
> - implement interface version 1.3
> ---
> include/hw/acpi/tpm.h | 8 +
> hw/i386/acpi-build.c | 423 +++++++++++++++++++++++++++++++++++++++++-
> docs/specs/tpm.txt | 79 ++++++++
> 3 files changed, 509 insertions(+), 1 deletion(-)
>
> diff --git a/include/hw/acpi/tpm.h b/include/hw/acpi/tpm.h
> index f79d68a77a..e0bd07862e 100644
> --- a/include/hw/acpi/tpm.h
> +++ b/include/hw/acpi/tpm.h
> @@ -196,4 +196,12 @@ REG32(CRB_DATA_BUFFER, 0x80)
> #define TPM_PPI_VERSION_NONE 0
> #define TPM_PPI_VERSION_1_30 1
>
> +/* whether function is blocked by BIOS settings; bits 0, 1, 2 */
> +#define TPM_PPI_FUNC_NOT_IMPLEMENTED (0 << 0)
> +#define TPM_PPI_FUNC_BIOS_ONLY (1 << 0)
> +#define TPM_PPI_FUNC_BLOCKED (2 << 0)
> +#define TPM_PPI_FUNC_ALLOWED_USR_REQ (3 << 0)
> +#define TPM_PPI_FUNC_ALLOWED_USR_NOT_REQ (4 << 0)
> +#define TPM_PPI_FUNC_MASK (7 << 0)
> +
> #endif /* HW_ACPI_TPM_H */
> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> index d9320845ed..d815af4eef 100644
> --- a/hw/i386/acpi-build.c
> +++ b/hw/i386/acpi-build.c
> @@ -43,6 +43,7 @@
> #include "hw/acpi/memory_hotplug.h"
> #include "sysemu/tpm.h"
> #include "hw/acpi/tpm.h"
> +#include "hw/tpm/tpm_ppi.h"
> #include "hw/acpi/vmgenid.h"
> #include "sysemu/tpm_backend.h"
> #include "hw/timer/mc146818rtc_regs.h"
> @@ -1789,6 +1790,421 @@ static Aml *build_q35_osc_method(void)
> return method;
> }
>
> +static void
> +build_tpm_ppi(Aml *dev)
> +{
> + Aml *method, *name, *field, *ifctx, *ifctx2, *ifctx3, *pak;
> + int i;
> +
> + if (!object_property_get_bool(OBJECT(tpm_find()), "ppi", &error_abort)) {
> + return;
> + }
> + /*
> + * TPP1 is for the flags that indicate which PPI operations
> + * are supported by the firmware. The firmware is expected to
> + * write these flags.
> + */
> + aml_append(dev,
> + aml_operation_region("TPP1", AML_SYSTEM_MEMORY,
> + aml_int(TPM_PPI_ADDR_BASE), 0x100));
> + field = aml_field("TPP1", AML_ANY_ACC, AML_NOLOCK, AML_PRESERVE);
> + for (i = 0; i < 0x100; i++) {
> + char *tmp = g_strdup_printf("FN%02X", i);
> + aml_append(field, aml_named_field(tmp, 8));
> + g_free(tmp);
> + }
> + aml_append(dev, field);
> +
> + /*
> + * TPP2 is for the registers that ACPI code used to pass
> + * the PPI code and parameter (PPRQ, PPRM) to the firmware.
> + */
> + aml_append(dev,
> + aml_operation_region("TPP2", AML_SYSTEM_MEMORY,
> + aml_int(TPM_PPI_ADDR_BASE + 0x100),
> + 0x5A));
> + field = aml_field("TPP2", AML_ANY_ACC, AML_NOLOCK, AML_PRESERVE);
> + aml_append(field, aml_named_field("PPIN", 8));
> + aml_append(field, aml_named_field("PPIP", 32));
> + aml_append(field, aml_named_field("PPRP", 32));
> + aml_append(field, aml_named_field("PPRQ", 32));
> + aml_append(field, aml_named_field("PPRM", 32));
> + aml_append(field, aml_named_field("LPPR", 32));
> + aml_append(dev, field);
> +
> + /*
> + * A function to return the value of DerefOf (FUNC [N]), by using
> + * accessing the fields individually instead. This is a workaround
> + * for what looks like a Windows ACPI bug in all versions so far
> + * (fwiw, DerefOf (FUNC [N]) works on Linux).
> + */
> + method = aml_method("TPFN", 1, AML_SERIALIZED);
> + {
> + for (i = 0; i < 0x100; i++) {
> + ifctx = aml_if(aml_equal(aml_int(i), aml_arg(0)));
> + {
> + aml_append(ifctx, aml_return(aml_name("FN%02X", i)));
> + }
> + aml_append(method, ifctx);
> + }
> + aml_append(method, aml_return(aml_int(0)));
> + }
> + aml_append(dev, method);
> +
> + pak = aml_package(2);
> + aml_append(pak, aml_int(0));
> + aml_append(pak, aml_int(0));
> + name = aml_name_decl("TPM2", pak);
> + aml_append(dev, name);
> +
> + pak = aml_package(3);
> + aml_append(pak, aml_int(0));
> + aml_append(pak, aml_int(0));
> + aml_append(pak, aml_int(0));
> + name = aml_name_decl("TPM3", pak);
> + aml_append(dev, name);
> +
> + method = aml_method("_DSM", 4, AML_SERIALIZED);
> + {
> + uint8_t zerobyte[1] = { 0 };
> + Aml *func_idx, *rev, *op, *op_arg, *op_flags;
> +
> + ifctx = aml_if(
> + aml_equal(aml_arg(0),
> + aml_touuid("3DDDFAA6-361B-4EB4-A424-8D10089D1653")));
> + {
> + func_idx = aml_local(0);
> + aml_append(ifctx,
> + aml_store(aml_to_integer(aml_arg(2)), func_idx));
> +
> + /* standard DSM query function */
> + func_idx = aml_local(0);
> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(0)));
> + {
> + uint8_t byte_list[2] = { 0xff, 0x01 };
> + aml_append(ifctx2, aml_return(aml_buffer(2, byte_list)));
> + }
> + aml_append(ifctx, ifctx2);
> +
> + /*
> + * 8.1.1 Get Physical Presence Interface Version
For this and other instances please include the
1st version of spec that includes the specific interface,
and refer to chapter #s from that spec.
E.g. I see this in version 1 of spec but it's a
different chapter there.
Listing earliest version is important as it gives you
an idea which guests will support it.
> + *
> + * Arg 2 (Integer): Function Index = 1
> + * Arg 3 (Package): Arguments = Empty Package
> + * Returns: Type: String
> + */
> + func_idx = aml_local(0);
> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(1)));
> + {
> + aml_append(ifctx2, aml_return(aml_string("1.3")));
> + }
> + aml_append(ifctx, ifctx2);
> +
> + /*
> + * 8.1.2 Submit TPM Operation Request to Pre-OS Environment
> + *
> + * Arg 2 (Integer): Function Index = 2
> + * Arg 3 (Package): Arguments = Package: Type: Integer
> + * Operation Value of the Request
> + * Returns: Type: Integer
> + * 0: Success
> + * 1: Operation Value of the Request Not Supported
> + * 2: General Failure
> + */
> + func_idx = aml_local(0);
> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(2)));
> + {
> + /* get opcode */
> + op = aml_derefof(aml_index(aml_arg(3), aml_int(0)));
> + aml_append(ifctx2, aml_store(op, aml_local(0)));
> +
> + /* get opcode flags */
> + op = aml_local(0);
> + aml_append(ifctx2,
> + aml_store(aml_call1("TPFN", op), aml_local(1)));
> +
> + op_flags = aml_local(1);
> + /* if func[opcode] & TPM_PPI_FUNC_NOT_IMPLEMENTED */
> + ifctx3 = aml_if(
> + aml_equal(
> + aml_and(op_flags, aml_int(TPM_PPI_FUNC_MASK), NULL),
> + aml_int(TPM_PPI_FUNC_NOT_IMPLEMENTED)));
> + {
> + /* 1: not implemented */
> + aml_append(ifctx3, aml_return(aml_int(1)));
> + }
> + aml_append(ifctx2, ifctx3);
> +
> + op = aml_local(0);
> + aml_append(ifctx2, aml_store(op, aml_name("PPRQ")));
> + aml_append(ifctx2, aml_store(aml_int(0), aml_name("PPRM")));
> + /* 0: success */
> + aml_append(ifctx2, aml_return(aml_int(0)));
> + }
> + aml_append(ifctx, ifctx2);
> +
> + /*
> + * 8.1.3 Get Pending TPM Operation Requested By the OS
> + *
> + * Arg 2 (Integer): Function Index = 3
> + * Arg 3 (Package): Arguments = Empty Package
> + * Returns: Type: Package of Integers
> + * Integer 1: Function Return code
> + * 0: Success
> + * 1: General Failure
> + * Integer 2: Pending operation requested by the OS
> + * 0: None
> + * >0: Operation Value of the Pending Request
> + * Integer 3: Optional argument to pending operation
> + * requested by the OS
> + * 0: None
> + * >0: Argument Value of the Pending Request
> + */
> + func_idx = aml_local(0);
> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(3)));
> + {
> + /* revision to integer */
> + aml_append(ifctx2,
> + aml_store(
> + aml_to_integer(aml_arg(1)),
> + aml_local(1)));
> + /*
> + * Revision ID of 1, no integer parameter beyond
> + * parameter two are expected
> + */
> + rev = aml_local(1);
> + ifctx3 = aml_if(aml_equal(rev, aml_int(1)));
> + {
> + /* TPM2[1] = PPRQ */
> + aml_append(ifctx3,
> + aml_store(
> + aml_name("PPRQ"),
> + aml_index(aml_name("TPM2"), aml_int(1))));
> + aml_append(ifctx3, aml_return(aml_name("TPM2")));
> + }
> + aml_append(ifctx2, ifctx3);
> +
> + /*
> + * A return value of {0, 23, 1} indicates that
> + * operation 23 with argument 1 is pending.
> + */
> + rev = aml_local(1);
> + ifctx3 = aml_if(aml_equal(rev, aml_int(2)));
> + {
> + /* TPM3[1] = PPRQ */
> + aml_append(ifctx3,
> + aml_store(
> + aml_name("PPRQ"),
> + aml_index(aml_name("TPM3"), aml_int(1))));
> + /* TPM3[2] = PPRM */
> + aml_append(ifctx3,
> + aml_store(
> + aml_name("PPRM"),
> + aml_index(aml_name("TPM3"), aml_int(2))));
> + aml_append(ifctx3, aml_return(aml_name("TPM3")));
> + }
> + aml_append(ifctx2, ifctx3);
> + }
> + aml_append(ifctx, ifctx2);
> +
> + /*
> + * 8.1.4 Get Platform-Specific Action to Transition to
> + * Pre-OS Environment
> + *
> + * Arg 2 (Integer): Function Index = 4
> + * Arg 3 (Package): Arguments = Empty Package
> + * Returns: Type: Integer
> + * 0: None
> + * 1: Shutdown
> + * 2: Reboot
> + * 3: OS Vendor-specific
> + */
> + func_idx = aml_local(0);
> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(4)));
> + {
> + /* reboot */
> + aml_append(ifctx2, aml_return(aml_int(2)));
> + }
> + aml_append(ifctx, ifctx2);
> +
> + /*
> + * 8.1.5 Return TPM Operation Response to OS Environment
> + *
> + * Arg 2 (Integer): Function Index = 5
> + * Arg 3 (Package): Arguments = Empty Package
> + * Returns: Type: Package of Integer
> + * Integer 1: Function Return code
> + * 0: Success
> + * 1: General Failure
> + * Integer 2: Most recent operation request
> + * 0: None
> + * >0: Operation Value of the most recent request
> + * Integer 3: Response to the most recent operation request
> + * 0: Success
> + * 0x00000001..0x00000FFF: Corresponding TPM
> + * error code
> + * 0xFFFFFFF0: User Abort or timeout of dialog
> + * 0xFFFFFFF1: firmware Failure
> + */
> + func_idx = aml_local(0);
> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(5)));
> + {
> + /* TPM3[1] = LPPR */
> + aml_append(ifctx2,
> + aml_store(
> + aml_name("LPPR"),
> + aml_index(aml_name("TPM3"), aml_int(1))));
> + /* TPM3[2] = PPRP */
> + aml_append(ifctx2,
> + aml_store(
> + aml_name("PPRP"),
> + aml_index(aml_name("TPM3"), aml_int(2))));
> + aml_append(ifctx2, aml_return(aml_name("TPM3")));
> + }
> + aml_append(ifctx, ifctx2);
> +
> + /*
> + * 8.1.6 Submit preferred user language
> + *
> + * Arg 2 (Integer): Function Index = 6
> + * Arg 3 (Package): Arguments = String Package
> + * Preferred language code
> + * Returns: Type: Integer
> + * Function Return Code
> + * 3: Not implemented
> + */
> + func_idx = aml_local(0);
> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(6)));
> + {
> + /* 3 = not implemented */
> + aml_append(ifctx2, aml_return(aml_int(3)));
> + }
> + aml_append(ifctx, ifctx2);
> +
> + /*
> + * 8.1.7 Submit TPM Operation Request to Pre-OS Environment 2
> + *
> + * Arg 2 (Integer): Function Index = 7
> + * Arg 3 (Package): Arguments = Package: Type: Integer
> + * Integer 1: Operation Value of the Request
> + * Integer 2: Argument for Operation (optional)
> + * Returns: Type: Integer
> + * 0: Success
> + * 1: Not Implemented
> + * 2: General Failure
> + * 3: Operation blocked by current firmware settings
> + */
> + func_idx = aml_local(0);
> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(7)));
> + {
> + /* get opcode */
> + op = aml_derefof(aml_index(aml_arg(3), aml_int(0)));
> + aml_append(ifctx2, aml_store(op, aml_local(0)));
> +
> + /* get opcode flags */
> + op = aml_local(0);
> + aml_append(ifctx2, aml_store(aml_call1("TPFN", op),
> + aml_local(1)));
> + /* if func[opcode] & TPM_PPI_FUNC_NOT_IMPLEMENTED */
> + op_flags = aml_local(1);
> + ifctx3 = aml_if(
> + aml_equal(
> + aml_and(op_flags, aml_int(TPM_PPI_FUNC_MASK), NULL),
> + aml_int(TPM_PPI_FUNC_NOT_IMPLEMENTED)));
> + {
> + /* 1: not implemented */
> + aml_append(ifctx3, aml_return(aml_int(1)));
> + }
> + aml_append(ifctx2, ifctx3);
> +
> + /* if func[opcode] & TPM_PPI_FUNC_BLOCKED */
> + op_flags = aml_local(1);
> + ifctx3 = aml_if(
> + aml_equal(
> + aml_and(op_flags, aml_int(TPM_PPI_FUNC_MASK), NULL),
> + aml_int(TPM_PPI_FUNC_BLOCKED)));
> + {
> + /* 3: blocked by firmware */
> + aml_append(ifctx3, aml_return(aml_int(3)));
> + }
> + aml_append(ifctx2, ifctx3);
> +
> + /* revision to integer */
> + aml_append(ifctx2,
> + aml_store(
> + aml_to_integer(aml_arg(1)),
> + aml_local(1)));
> +
> + rev = aml_local(1);
> + ifctx3 = aml_if(aml_equal(rev, aml_int(1)));
> + {
> + /* revision 1 */
> + /* PPRQ = op */
> + op = aml_local(0);
> + aml_append(ifctx3, aml_store(op, aml_name("PPRQ")));
> + /* no argument, PPRM = 0 */
> + aml_append(ifctx3, aml_store(aml_int(0),
> + aml_name("PPRM")));
> + }
> + aml_append(ifctx2, ifctx3);
> +
> + rev = aml_local(1);
> + ifctx3 = aml_if(aml_equal(rev, aml_int(2)));
> + {
> + /* revision 2 */
> + /* PPRQ = op */
> + op = aml_local(0);
> + op_arg = aml_derefof(aml_index(aml_arg(3), aml_int(1)));
> + aml_append(ifctx3, aml_store(op, aml_name("PPRQ")));
> + /* PPRM = arg3[1] */
> + aml_append(ifctx3, aml_store(op_arg, aml_name("PPRM")));
> + }
> + aml_append(ifctx2, ifctx3);
> + /* 0: success */
> + aml_append(ifctx2, aml_return(aml_int(0)));
> + }
> + aml_append(ifctx, ifctx2);
> +
> + /*
> + * 8.1.8 Get User Confirmation Status for Operation
> + *
> + * Arg 2 (Integer): Function Index = 8
> + * Arg 3 (Package): Arguments = Package: Type: Integer
> + * Operation Value that may need user confirmation
> + * Returns: Type: Integer
> + * 0: Not implemented
> + * 1: Firmware only
> + * 2: Blocked for OS by firmware configuration
> + * 3: Allowed and physically present user required
> + * 4: Allowed and physically present user not required
> + */
> + func_idx = aml_local(0);
> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(8)));
> + {
> + /* get opcode */
> + op = aml_derefof(aml_index(aml_arg(3), aml_int(0)));
> + aml_append(ifctx2, aml_store(op, aml_local(0)));
> +
> + /* get opcode flags */
> + op = aml_local(0);
> + aml_append(ifctx2, aml_store(aml_call1("TPFN", op),
> + aml_local(1)));
> + op_flags = aml_local(1);
> + /* return confirmation status code */
> + aml_append(ifctx2,
> + aml_return(
> + aml_and(op_flags,
> + aml_int(TPM_PPI_FUNC_MASK), NULL)));
> + }
> + aml_append(ifctx, ifctx2);
> +
> + aml_append(ifctx, aml_return(aml_buffer(1, zerobyte)));
> + }
> + aml_append(method, ifctx);
> + }
> + aml_append(dev, method);
> +}
> +
> static void
> build_dsdt(GArray *table_data, BIOSLinker *linker,
> AcpiPmInfo *pm, AcpiMiscInfo *misc,
> @@ -2153,6 +2569,9 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
> */
> /* aml_append(crs, aml_irq_no_flags(TPM_TIS_IRQ)); */
> aml_append(dev, aml_name_decl("_CRS", crs));
> +
> + build_tpm_ppi(dev);
> +
> aml_append(scope, dev);
> }
>
> @@ -2172,6 +2591,8 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
> aml_append(method, aml_return(aml_int(0x0f)));
> aml_append(dev, method);
>
> + build_tpm_ppi(dev);
> +
> aml_append(sb_scope, dev);
> }
>
> @@ -2920,7 +3341,7 @@ void acpi_setup(void)
> tpm_config = (FWCfgTPMConfig) {
> .tpmppi_address = cpu_to_le32(TPM_PPI_ADDR_BASE),
> .tpm_version = cpu_to_le32(tpm_get_version(tpm_find())),
> - .tpmppi_version = cpu_to_le32(TPM_PPI_VERSION_NONE)
> + .tpmppi_version = cpu_to_le32(TPM_PPI_VERSION_1_30)
> };
> fw_cfg_add_file(pcms->fw_cfg, "etc/tpm/config",
> &tpm_config, sizeof tpm_config);
> diff --git a/docs/specs/tpm.txt b/docs/specs/tpm.txt
> index 2ddb768084..c27762c723 100644
> --- a/docs/specs/tpm.txt
> +++ b/docs/specs/tpm.txt
> @@ -62,6 +62,85 @@ URL:
>
> https://trustedcomputinggroup.org/tcg-acpi-specification/
>
> +== ACPI PPI Interface ==
> +
> +QEMU supports the Physical Presence Interface (PPI) for TPM 1.2 and TPM 2. This
> +interface requires ACPI and firmware support. The specification can be found at
> +the following URL:
> +
> +https://trustedcomputinggroup.org/resource/tcg-physical-presence-interface-specification/
> +
> +PPI enables a system administrator (root) to request a modification to the
> +TPM upon reboot. The PPI specification defines the operation requests and the
> +actions the firmware has to take. The system administrator passes the operation
> +request number to the firmware through an ACPI interface which writes this
> +number to a memory location that the firmware knows. Upon reboot, the firmware
> +finds the number and sends commands to the the TPM. The firmware writes the TPM
> +result code and the operation request number to a memory location that ACPI can
> +read from and pass the result on to the administrator.
> +
> +The PPI specification defines a set of mandatory and optional operations for
> +the firmware to implement. The ACPI interface also allows an administrator to
> +list the supported operations. In QEMU the ACPI code is generated by QEMU, yet
> +the firmware needs to implement support on a per-operations basis, and
> +different firmwares may support a different subset. Therefore, QEMU introduces
> +the virtual memory device for PPI where the firmware can indicate which
> +operations it supports and ACPI can enable the ones that are supported and
> +disable all others. This interface lies in main memory and has the following
> +layout:
> +
> + +----------+--------+--------+-------------------------------------------+
> + | Field | Length | Offset | Description |
> + +----------+--------+--------+-------------------------------------------+
> + | func | 0x100 | 0x000 | Firmware sets values for each supported |
> + | | | | operation. See defined values below. |
> + +----------+--------+--------+-------------------------------------------+
> + | ppin | 0x1 | 0x100 | SMI interrupt to use. Set by firmware. |
> + | | | | Not supported. |
> + +----------+--------+--------+-------------------------------------------+
> + | ppip | 0x4 | 0x101 | ACPI function index to pass to SMM code. |
> + | | | | Set by ACPI. Not supported. |
> + +----------+--------+--------+-------------------------------------------+
> + | pprp | 0x4 | 0x105 | Result of last executed operation. Set by |
> + | | | | firmware. See function index 5 for values.|
> + +----------+--------+--------+-------------------------------------------+
> + | pprq | 0x4 | 0x109 | Operation request number to execute. See |
> + | | | | 'Physical Presence Interface Operation |
> + | | | | Summary' tables in specs. Set by ACPI. |
> + +----------+--------+--------+-------------------------------------------+
> + | pprm | 0x4 | 0x10d | Operation request optional parameter. |
> + | | | | Values depend on operation. Set by ACPI. |
> + +----------+--------+--------+-------------------------------------------+
> + | lppr | 0x4 | 0x111 | Last executed operation request number. |
> + | | | | Copied from pprq field by firmware. |
> + +----------+--------+--------+-------------------------------------------+
> + | fret | 0x4 | 0x115 | Result code from SMM function. |
> + | | | | Not supported. |
> + +----------+--------+--------+-------------------------------------------+
> + | res1 | 0x40 | 0x119 | Reserved for future use |
> + +----------+--------+--------+-------------------------------------------+
> + | next_step| 0x1 | 0x159 | Operation to execute after reboot by |
> + | | | | firmware. Used by firmware. |
> + +----------+--------+--------+-------------------------------------------+
> +
> + The following values are supported for the 'func' field. They correspond
> + to the values used by ACPI function index 8.
> +
> + +----------+-------------------------------------------------------------+
> + | value | Description |
> + +----------+-------------------------------------------------------------+
> + | 0 | Operation is not implemented. |
> + +----------+-------------------------------------------------------------+
> + | 1 | Operation is only accessible through firmware. |
> + +----------+-------------------------------------------------------------+
> + | 2 | Operation is blocked for OS by firmware configuration. |
> + +----------+-------------------------------------------------------------+
> + | 3 | Operation is allowed and physically present user required. |
> + +----------+-------------------------------------------------------------+
> + | 4 | Operation is allowed and physically present user is not |
> + | | required. |
> + +----------+-------------------------------------------------------------+
> +
>
> QEMU files related to TPM ACPI tables:
> - hw/i386/acpi-build.c
> --
> 2.18.0.rc1
On Tue, 26 Jun 2018 14:23:43 +0200
Marc-André Lureau <marcandre.lureau@redhat.com> wrote:
> From: Stefan Berger <stefanb@linux.vnet.ibm.com>
>
> The TPM Physical Presence interface consists of an ACPI part, a shared
> memory part, and code in the firmware. Users can send messages to the
> firmware by writing a code into the shared memory through invoking the
> ACPI code. When a reboot happens, the firmware looks for the code and
> acts on it by sending sequences of commands to the TPM.
>
> This patch adds the ACPI code. It is similar to the one in EDK2 but doesn't
> assume that SMIs are necessary to use. It uses a similar datastructure for
> the shared memory as EDK2 does so that EDK2 and SeaBIOS could both make use
> of it. I extended the shared memory data structure with an array of 256
> bytes, one for each code that could be implemented. The array contains
> flags describing the individual codes. This decouples the ACPI implementation
> from the firmware implementation.
>
> The underlying TCG specification is accessible from the following page.
>
> https://trustedcomputinggroup.org/tcg-physical-presence-interface-specification/
>
> This patch implements version 1.30.
I've made several suggestions below how to improve aml part of patch a bit,
will review v6 once it's done
/hopefully it would be more readable, considering that ASM language is horrible to begin with/
>
> Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
>
> ---
>
> v6:
> - more code documentation (Marc-André)
> - use some explicit named variables to ease reading (Marc-André)
> - use fixed size fields/memory regions, remove PPI struct (Marc-André)
> - only add PPI ACPI methods if PPI is enabled (Marc-André)
> - document the qemu/firmware ACPI memory region (Stefan)
>
> v5 (Marc-André):
> - /struct tpm_ppi/struct TPMPPIData
>
> v4 (Marc-André):
> - replace 'DerefOf (FUNC [N])' with a function, to fix Windows ACPI
> handling.
> - replace 'return Package (..) {} ' with scoped variables, to fix
> Windows ACPI handling.
>
> v3:
> - add support for PPI to CRB
> - split up OperationRegion TPPI into two parts, one containing
> the registers (TPP1) and the other one the flags (TPP2); switched
> the order of the flags versus registers in the code
> - adapted ACPI code to small changes to the array of flags where
> previous flag 0 was removed and now shifting right wasn't always
> necessary anymore
>
> v2:
> - get rid of FAIL variable; function 5 was using it and always
> returns 0; the value is related to the ACPI function call not
> a possible failure of the TPM function call.
> - extend shared memory data structure with per-opcode entries
> holding flags and use those flags to determine what to return
> to caller
> - implement interface version 1.3
> ---
> include/hw/acpi/tpm.h | 8 +
> hw/i386/acpi-build.c | 423 +++++++++++++++++++++++++++++++++++++++++-
> docs/specs/tpm.txt | 79 ++++++++
> 3 files changed, 509 insertions(+), 1 deletion(-)
>
> diff --git a/include/hw/acpi/tpm.h b/include/hw/acpi/tpm.h
> index f79d68a77a..e0bd07862e 100644
> --- a/include/hw/acpi/tpm.h
> +++ b/include/hw/acpi/tpm.h
> @@ -196,4 +196,12 @@ REG32(CRB_DATA_BUFFER, 0x80)
> #define TPM_PPI_VERSION_NONE 0
> #define TPM_PPI_VERSION_1_30 1
>
> +/* whether function is blocked by BIOS settings; bits 0, 1, 2 */
> +#define TPM_PPI_FUNC_NOT_IMPLEMENTED (0 << 0)
> +#define TPM_PPI_FUNC_BIOS_ONLY (1 << 0)
> +#define TPM_PPI_FUNC_BLOCKED (2 << 0)
> +#define TPM_PPI_FUNC_ALLOWED_USR_REQ (3 << 0)
> +#define TPM_PPI_FUNC_ALLOWED_USR_NOT_REQ (4 << 0)
> +#define TPM_PPI_FUNC_MASK (7 << 0)
> +
> #endif /* HW_ACPI_TPM_H */
> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> index d9320845ed..d815af4eef 100644
> --- a/hw/i386/acpi-build.c
> +++ b/hw/i386/acpi-build.c
> @@ -43,6 +43,7 @@
> #include "hw/acpi/memory_hotplug.h"
> #include "sysemu/tpm.h"
> #include "hw/acpi/tpm.h"
> +#include "hw/tpm/tpm_ppi.h"
> #include "hw/acpi/vmgenid.h"
> #include "sysemu/tpm_backend.h"
> #include "hw/timer/mc146818rtc_regs.h"
> @@ -1789,6 +1790,421 @@ static Aml *build_q35_osc_method(void)
> return method;
> }
>
> +static void
> +build_tpm_ppi(Aml *dev)
> +{
> + Aml *method, *name, *field, *ifctx, *ifctx2, *ifctx3, *pak;
> + int i;
> +
> + if (!object_property_get_bool(OBJECT(tpm_find()), "ppi", &error_abort)) {
if tpm_find() == NULL -> BAAM???
I'd do it like this:
tmp = tpm_find()
if (TPM_IS_TIS(tpm) {
...
if (object_property_get_bool(tpm), "ppi", &error_abort)) {
build_tpm_ppi(tpm, dev)
}
...
}
if (TPM_IS_CRB(tpm))
{
....
}
a bit more verbose but then the reader won't have to jump inside of
build_tpm_ppi() if he/she is not interested in it.
> + return;
> + }
> + /*
> + * TPP1 is for the flags that indicate which PPI operations
> + * are supported by the firmware. The firmware is expected to
> + * write these flags.
> + */
> + aml_append(dev,
> + aml_operation_region("TPP1", AML_SYSTEM_MEMORY,
> + aml_int(TPM_PPI_ADDR_BASE), 0x100));
> + field = aml_field("TPP1", AML_ANY_ACC, AML_NOLOCK, AML_PRESERVE);
> + for (i = 0; i < 0x100; i++) {
> + char *tmp = g_strdup_printf("FN%02X", i);
> + aml_append(field, aml_named_field(tmp, 8));
> + g_free(tmp);
> + }
> + aml_append(dev, field);
> +
> + /*
> + * TPP2 is for the registers that ACPI code used to pass
> + * the PPI code and parameter (PPRQ, PPRM) to the firmware.
> + */
> + aml_append(dev,
> + aml_operation_region("TPP2", AML_SYSTEM_MEMORY,
> + aml_int(TPM_PPI_ADDR_BASE + 0x100),
> + 0x5A));
> + field = aml_field("TPP2", AML_ANY_ACC, AML_NOLOCK, AML_PRESERVE);
> + aml_append(field, aml_named_field("PPIN", 8));
> + aml_append(field, aml_named_field("PPIP", 32));
> + aml_append(field, aml_named_field("PPRP", 32));
> + aml_append(field, aml_named_field("PPRQ", 32));
> + aml_append(field, aml_named_field("PPRM", 32));
> + aml_append(field, aml_named_field("LPPR", 32));
> + aml_append(dev, field);
> +
> + /*
> + * A function to return the value of DerefOf (FUNC [N]), by using
> + * accessing the fields individually instead. This is a workaround
> + * for what looks like a Windows ACPI bug in all versions so far
> + * (fwiw, DerefOf (FUNC [N]) works on Linux).
> + */
> + method = aml_method("TPFN", 1, AML_SERIALIZED);
> + {
> + for (i = 0; i < 0x100; i++) {
> + ifctx = aml_if(aml_equal(aml_int(i), aml_arg(0)));
> + {
> + aml_append(ifctx, aml_return(aml_name("FN%02X", i)));
> + }
> + aml_append(method, ifctx);
> + }
> + aml_append(method, aml_return(aml_int(0)));
> + }
> + aml_append(dev, method);
> +
> + pak = aml_package(2);
> + aml_append(pak, aml_int(0));
> + aml_append(pak, aml_int(0));
> + name = aml_name_decl("TPM2", pak);
> + aml_append(dev, name);
> +
> + pak = aml_package(3);
> + aml_append(pak, aml_int(0));
> + aml_append(pak, aml_int(0));
> + aml_append(pak, aml_int(0));
> + name = aml_name_decl("TPM3", pak);
Aml one = aml_int(1)
Aml tpm3 = local(x)
aml_store(pak, tpm3)
... and then later ...
{
/* TPM2[1] = PPRQ */
aml_append(ifctx3, aml_store(aml_name("PPRQ"), aml_index(tpm2, one)));
aml_append(ifctx3, aml_return(tpm2));
which would make code a bit more readable
> + aml_append(dev, name);
both packages could be local vars as return is done by value
> +
> + method = aml_method("_DSM", 4, AML_SERIALIZED);
> + {
> + uint8_t zerobyte[1] = { 0 };
> + Aml *func_idx, *rev, *op, *op_arg, *op_flags;
> +
> + ifctx = aml_if(
> + aml_equal(aml_arg(0),
> + aml_touuid("3DDDFAA6-361B-4EB4-A424-8D10089D1653")));
aml_equal(uuid, aml_touuid("3DDDFAA6-361B-4EB4-A424-8D10089D1653"))
> + {
> + func_idx = aml_local(0);
> + aml_append(ifctx,
> + aml_store(aml_to_integer(aml_arg(2)), func_idx));
why do you need aml_to_integer() cast here?
Wouldn't following just work:
Aml function = aml_arg(2)
I'd suggest to use "function" for consistency with nvdimm _DSM
you can use the same naming approach for other arguments i.e.
arguments = aml_arg(3)
> +
> + /* standard DSM query function */
> + func_idx = aml_local(0);
I don't think you need to init it twice.
> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(0)));
> + {
> + uint8_t byte_list[2] = { 0xff, 0x01 };
> + aml_append(ifctx2, aml_return(aml_buffer(2, byte_list)));
> + }
> + aml_append(ifctx, ifctx2);
> +
> + /*
> + * 8.1.1 Get Physical Presence Interface Version
like Michael noted use version/chapter pair to as reference
ex: /* ACPI 1.0b: 16.2.5.2 Named Objects Encoding: DefOpRegion */
> + *
> + * Arg 2 (Integer): Function Index = 1
> + * Arg 3 (Package): Arguments = Empty Package
> + * Returns: Type: String
> + */
> + func_idx = aml_local(0);
not needed
> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(1)));
> + {
> + aml_append(ifctx2, aml_return(aml_string("1.3")));
> + }
> + aml_append(ifctx, ifctx2);
> +
> + /*
> + * 8.1.2 Submit TPM Operation Request to Pre-OS Environment
> + *
> + * Arg 2 (Integer): Function Index = 2
> + * Arg 3 (Package): Arguments = Package: Type: Integer
> + * Operation Value of the Request
> + * Returns: Type: Integer
> + * 0: Success
> + * 1: Operation Value of the Request Not Supported
> + * 2: General Failure
> + */
> + func_idx = aml_local(0);
ditto and the same in other places
> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(2)));
> + {
> + /* get opcode */
> + op = aml_derefof(aml_index(aml_arg(3), aml_int(0)));
> + aml_append(ifctx2, aml_store(op, aml_local(0)));
^^^ what this local(0) is? suggest to use named var here (in C sense)
> +
> + /* get opcode flags */
> + op = aml_local(0);
use other local to make ASL less confusion (i.e. try not to reuse local vars for something else)
> + aml_append(ifctx2,
> + aml_store(aml_call1("TPFN", op), aml_local(1)));
^^^ what this local(1) is?
> +
> + op_flags = aml_local(1);
I'd init all named vars at the top of function where it's easy to see what is what
and use them later. ex: nvdimm_build_common_dsm()
> + /* if func[opcode] & TPM_PPI_FUNC_NOT_IMPLEMENTED */
> + ifctx3 = aml_if(
> + aml_equal(
> + aml_and(op_flags, aml_int(TPM_PPI_FUNC_MASK), NULL),
> + aml_int(TPM_PPI_FUNC_NOT_IMPLEMENTED)));
> + {
> + /* 1: not implemented */
may be the same language as in above comment
/* 1: Operation Value of the Request Not Supported */
same applies to other return values
> + aml_append(ifctx3, aml_return(aml_int(1)));
> + }
> + aml_append(ifctx2, ifctx3);
> +
> + op = aml_local(0);
> + aml_append(ifctx2, aml_store(op, aml_name("PPRQ")));
> + aml_append(ifctx2, aml_store(aml_int(0), aml_name("PPRM")));
> + /* 0: success */
> + aml_append(ifctx2, aml_return(aml_int(0)));
> + }
> + aml_append(ifctx, ifctx2);
> +
> + /*
> + * 8.1.3 Get Pending TPM Operation Requested By the OS
> + *
> + * Arg 2 (Integer): Function Index = 3
> + * Arg 3 (Package): Arguments = Empty Package
> + * Returns: Type: Package of Integers
> + * Integer 1: Function Return code
> + * 0: Success
> + * 1: General Failure
> + * Integer 2: Pending operation requested by the OS
> + * 0: None
> + * >0: Operation Value of the Pending Request
> + * Integer 3: Optional argument to pending operation
> + * requested by the OS
> + * 0: None
> + * >0: Argument Value of the Pending Request
> + */
> + func_idx = aml_local(0);
> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(3)));
> + {
> + /* revision to integer */
> + aml_append(ifctx2,
> + aml_store(
> + aml_to_integer(aml_arg(1)),
same do you need cast here, by spec it's 'int' already?
> + aml_local(1)));
why store into local var, couldn't it be used directly ?
> + /*
> + * Revision ID of 1, no integer parameter beyond
> + * parameter two are expected
> + */
> + rev = aml_local(1);
> + ifctx3 = aml_if(aml_equal(rev, aml_int(1)));
> + {
> + /* TPM2[1] = PPRQ */
> + aml_append(ifctx3,
> + aml_store(
> + aml_name("PPRQ"),
> + aml_index(aml_name("TPM2"), aml_int(1))));
> + aml_append(ifctx3, aml_return(aml_name("TPM2")));
> + }
> + aml_append(ifctx2, ifctx3);
> +
> + /*
> + * A return value of {0, 23, 1} indicates that
> + * operation 23 with argument 1 is pending.
> + */
> + rev = aml_local(1);
> + ifctx3 = aml_if(aml_equal(rev, aml_int(2)));
> + {
> + /* TPM3[1] = PPRQ */
> + aml_append(ifctx3,
> + aml_store(
> + aml_name("PPRQ"),
> + aml_index(aml_name("TPM3"), aml_int(1))));
> + /* TPM3[2] = PPRM */
> + aml_append(ifctx3,
> + aml_store(
> + aml_name("PPRM"),
> + aml_index(aml_name("TPM3"), aml_int(2))));
> + aml_append(ifctx3, aml_return(aml_name("TPM3")));
> + }
> + aml_append(ifctx2, ifctx3);
> + }
> + aml_append(ifctx, ifctx2);
> +
> + /*
> + * 8.1.4 Get Platform-Specific Action to Transition to
> + * Pre-OS Environment
> + *
> + * Arg 2 (Integer): Function Index = 4
> + * Arg 3 (Package): Arguments = Empty Package
> + * Returns: Type: Integer
> + * 0: None
> + * 1: Shutdown
> + * 2: Reboot
> + * 3: OS Vendor-specific
> + */
> + func_idx = aml_local(0);
> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(4)));
> + {
> + /* reboot */
> + aml_append(ifctx2, aml_return(aml_int(2)));
> + }
> + aml_append(ifctx, ifctx2);
> +
> + /*
> + * 8.1.5 Return TPM Operation Response to OS Environment
> + *
> + * Arg 2 (Integer): Function Index = 5
> + * Arg 3 (Package): Arguments = Empty Package
> + * Returns: Type: Package of Integer
> + * Integer 1: Function Return code
> + * 0: Success
> + * 1: General Failure
> + * Integer 2: Most recent operation request
> + * 0: None
> + * >0: Operation Value of the most recent request
> + * Integer 3: Response to the most recent operation request
> + * 0: Success
> + * 0x00000001..0x00000FFF: Corresponding TPM
> + * error code
> + * 0xFFFFFFF0: User Abort or timeout of dialog
> + * 0xFFFFFFF1: firmware Failure
> + */
> + func_idx = aml_local(0);
> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(5)));
> + {
> + /* TPM3[1] = LPPR */
> + aml_append(ifctx2,
> + aml_store(
> + aml_name("LPPR"),
> + aml_index(aml_name("TPM3"), aml_int(1))));
> + /* TPM3[2] = PPRP */
> + aml_append(ifctx2,
> + aml_store(
> + aml_name("PPRP"),
> + aml_index(aml_name("TPM3"), aml_int(2))));
> + aml_append(ifctx2, aml_return(aml_name("TPM3")));
> + }
> + aml_append(ifctx, ifctx2);
> +
> + /*
> + * 8.1.6 Submit preferred user language
> + *
> + * Arg 2 (Integer): Function Index = 6
> + * Arg 3 (Package): Arguments = String Package
> + * Preferred language code
> + * Returns: Type: Integer
> + * Function Return Code
> + * 3: Not implemented
> + */
> + func_idx = aml_local(0);
> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(6)));
> + {
> + /* 3 = not implemented */
> + aml_append(ifctx2, aml_return(aml_int(3)));
> + }
> + aml_append(ifctx, ifctx2);
> +
> + /*
> + * 8.1.7 Submit TPM Operation Request to Pre-OS Environment 2
> + *
> + * Arg 2 (Integer): Function Index = 7
> + * Arg 3 (Package): Arguments = Package: Type: Integer
> + * Integer 1: Operation Value of the Request
> + * Integer 2: Argument for Operation (optional)
> + * Returns: Type: Integer
> + * 0: Success
> + * 1: Not Implemented
> + * 2: General Failure
> + * 3: Operation blocked by current firmware settings
> + */
> + func_idx = aml_local(0);
> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(7)));
> + {
> + /* get opcode */
> + op = aml_derefof(aml_index(aml_arg(3), aml_int(0)));
> + aml_append(ifctx2, aml_store(op, aml_local(0)));
> +
> + /* get opcode flags */
> + op = aml_local(0);
> + aml_append(ifctx2, aml_store(aml_call1("TPFN", op),
> + aml_local(1)));
> + /* if func[opcode] & TPM_PPI_FUNC_NOT_IMPLEMENTED */
> + op_flags = aml_local(1);
> + ifctx3 = aml_if(
> + aml_equal(
> + aml_and(op_flags, aml_int(TPM_PPI_FUNC_MASK), NULL),
> + aml_int(TPM_PPI_FUNC_NOT_IMPLEMENTED)));
> + {
> + /* 1: not implemented */
> + aml_append(ifctx3, aml_return(aml_int(1)));
> + }
> + aml_append(ifctx2, ifctx3);
> +
> + /* if func[opcode] & TPM_PPI_FUNC_BLOCKED */
> + op_flags = aml_local(1);
> + ifctx3 = aml_if(
> + aml_equal(
> + aml_and(op_flags, aml_int(TPM_PPI_FUNC_MASK), NULL),
> + aml_int(TPM_PPI_FUNC_BLOCKED)));
> + {
> + /* 3: blocked by firmware */
> + aml_append(ifctx3, aml_return(aml_int(3)));
> + }
> + aml_append(ifctx2, ifctx3);
> +
> + /* revision to integer */
> + aml_append(ifctx2,
> + aml_store(
> + aml_to_integer(aml_arg(1)),
> + aml_local(1)));
> +
> + rev = aml_local(1);
> + ifctx3 = aml_if(aml_equal(rev, aml_int(1)));
> + {
> + /* revision 1 */
> + /* PPRQ = op */
> + op = aml_local(0);
> + aml_append(ifctx3, aml_store(op, aml_name("PPRQ")));
> + /* no argument, PPRM = 0 */
> + aml_append(ifctx3, aml_store(aml_int(0),
> + aml_name("PPRM")));
> + }
> + aml_append(ifctx2, ifctx3);
> +
> + rev = aml_local(1);
> + ifctx3 = aml_if(aml_equal(rev, aml_int(2)));
> + {
> + /* revision 2 */
> + /* PPRQ = op */
> + op = aml_local(0);
> + op_arg = aml_derefof(aml_index(aml_arg(3), aml_int(1)));
> + aml_append(ifctx3, aml_store(op, aml_name("PPRQ")));
> + /* PPRM = arg3[1] */
> + aml_append(ifctx3, aml_store(op_arg, aml_name("PPRM")));
> + }
> + aml_append(ifctx2, ifctx3);
> + /* 0: success */
> + aml_append(ifctx2, aml_return(aml_int(0)));
> + }
> + aml_append(ifctx, ifctx2);
> +
> + /*
> + * 8.1.8 Get User Confirmation Status for Operation
> + *
> + * Arg 2 (Integer): Function Index = 8
> + * Arg 3 (Package): Arguments = Package: Type: Integer
> + * Operation Value that may need user confirmation
> + * Returns: Type: Integer
> + * 0: Not implemented
> + * 1: Firmware only
> + * 2: Blocked for OS by firmware configuration
> + * 3: Allowed and physically present user required
> + * 4: Allowed and physically present user not required
> + */
> + func_idx = aml_local(0);
> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(8)));
> + {
> + /* get opcode */
> + op = aml_derefof(aml_index(aml_arg(3), aml_int(0)));
> + aml_append(ifctx2, aml_store(op, aml_local(0)));
> +
> + /* get opcode flags */
> + op = aml_local(0);
> + aml_append(ifctx2, aml_store(aml_call1("TPFN", op),
> + aml_local(1)));
> + op_flags = aml_local(1);
> + /* return confirmation status code */
> + aml_append(ifctx2,
> + aml_return(
> + aml_and(op_flags,
> + aml_int(TPM_PPI_FUNC_MASK), NULL)));
> + }
> + aml_append(ifctx, ifctx2);
> +
> + aml_append(ifctx, aml_return(aml_buffer(1, zerobyte)));
> + }
> + aml_append(method, ifctx);
> + }
> + aml_append(dev, method);
> +}
> +
> static void
> build_dsdt(GArray *table_data, BIOSLinker *linker,
> AcpiPmInfo *pm, AcpiMiscInfo *misc,
> @@ -2153,6 +2569,9 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
> */
> /* aml_append(crs, aml_irq_no_flags(TPM_TIS_IRQ)); */
> aml_append(dev, aml_name_decl("_CRS", crs));
> +
> + build_tpm_ppi(dev);
> +
> aml_append(scope, dev);
> }
>
> @@ -2172,6 +2591,8 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
> aml_append(method, aml_return(aml_int(0x0f)));
> aml_append(dev, method);
>
> + build_tpm_ppi(dev);
> +
> aml_append(sb_scope, dev);
> }
>
> @@ -2920,7 +3341,7 @@ void acpi_setup(void)
> tpm_config = (FWCfgTPMConfig) {
> .tpmppi_address = cpu_to_le32(TPM_PPI_ADDR_BASE),
> .tpm_version = cpu_to_le32(tpm_get_version(tpm_find())),
> - .tpmppi_version = cpu_to_le32(TPM_PPI_VERSION_NONE)
> + .tpmppi_version = cpu_to_le32(TPM_PPI_VERSION_1_30)
s/cpu_to_le32//
> };
> fw_cfg_add_file(pcms->fw_cfg, "etc/tpm/config",
> &tpm_config, sizeof tpm_config);
> diff --git a/docs/specs/tpm.txt b/docs/specs/tpm.txt
> index 2ddb768084..c27762c723 100644
> --- a/docs/specs/tpm.txt
> +++ b/docs/specs/tpm.txt
> @@ -62,6 +62,85 @@ URL:
>
> https://trustedcomputinggroup.org/tcg-acpi-specification/
>
> +== ACPI PPI Interface ==
> +
> +QEMU supports the Physical Presence Interface (PPI) for TPM 1.2 and TPM 2. This
> +interface requires ACPI and firmware support. The specification can be found at
> +the following URL:
> +
> +https://trustedcomputinggroup.org/resource/tcg-physical-presence-interface-specification/
> +
> +PPI enables a system administrator (root) to request a modification to the
> +TPM upon reboot. The PPI specification defines the operation requests and the
> +actions the firmware has to take. The system administrator passes the operation
> +request number to the firmware through an ACPI interface which writes this
> +number to a memory location that the firmware knows. Upon reboot, the firmware
> +finds the number and sends commands to the the TPM. The firmware writes the TPM
> +result code and the operation request number to a memory location that ACPI can
> +read from and pass the result on to the administrator.
> +
> +The PPI specification defines a set of mandatory and optional operations for
> +the firmware to implement. The ACPI interface also allows an administrator to
> +list the supported operations. In QEMU the ACPI code is generated by QEMU, yet
> +the firmware needs to implement support on a per-operations basis, and
> +different firmwares may support a different subset. Therefore, QEMU introduces
> +the virtual memory device for PPI where the firmware can indicate which
> +operations it supports and ACPI can enable the ones that are supported and
> +disable all others. This interface lies in main memory and has the following
> +layout:
> +
> + +----------+--------+--------+-------------------------------------------+
> + | Field | Length | Offset | Description |
> + +----------+--------+--------+-------------------------------------------+
> + | func | 0x100 | 0x000 | Firmware sets values for each supported |
> + | | | | operation. See defined values below. |
> + +----------+--------+--------+-------------------------------------------+
> + | ppin | 0x1 | 0x100 | SMI interrupt to use. Set by firmware. |
> + | | | | Not supported. |
> + +----------+--------+--------+-------------------------------------------+
> + | ppip | 0x4 | 0x101 | ACPI function index to pass to SMM code. |
> + | | | | Set by ACPI. Not supported. |
> + +----------+--------+--------+-------------------------------------------+
> + | pprp | 0x4 | 0x105 | Result of last executed operation. Set by |
> + | | | | firmware. See function index 5 for values.|
> + +----------+--------+--------+-------------------------------------------+
> + | pprq | 0x4 | 0x109 | Operation request number to execute. See |
> + | | | | 'Physical Presence Interface Operation |
> + | | | | Summary' tables in specs. Set by ACPI. |
> + +----------+--------+--------+-------------------------------------------+
> + | pprm | 0x4 | 0x10d | Operation request optional parameter. |
> + | | | | Values depend on operation. Set by ACPI. |
> + +----------+--------+--------+-------------------------------------------+
> + | lppr | 0x4 | 0x111 | Last executed operation request number. |
> + | | | | Copied from pprq field by firmware. |
> + +----------+--------+--------+-------------------------------------------+
> + | fret | 0x4 | 0x115 | Result code from SMM function. |
> + | | | | Not supported. |
> + +----------+--------+--------+-------------------------------------------+
> + | res1 | 0x40 | 0x119 | Reserved for future use |
> + +----------+--------+--------+-------------------------------------------+
> + | next_step| 0x1 | 0x159 | Operation to execute after reboot by |
> + | | | | firmware. Used by firmware. |
> + +----------+--------+--------+-------------------------------------------+
> +
> + The following values are supported for the 'func' field. They correspond
> + to the values used by ACPI function index 8.
> +
> + +----------+-------------------------------------------------------------+
> + | value | Description |
> + +----------+-------------------------------------------------------------+
> + | 0 | Operation is not implemented. |
> + +----------+-------------------------------------------------------------+
> + | 1 | Operation is only accessible through firmware. |
> + +----------+-------------------------------------------------------------+
> + | 2 | Operation is blocked for OS by firmware configuration. |
> + +----------+-------------------------------------------------------------+
> + | 3 | Operation is allowed and physically present user required. |
> + +----------+-------------------------------------------------------------+
> + | 4 | Operation is allowed and physically present user is not |
> + | | required. |
> + +----------+-------------------------------------------------------------+
> +
>
> QEMU files related to TPM ACPI tables:
> - hw/i386/acpi-build.c
On 06/27/2018 09:19 AM, Igor Mammedov wrote:
> On Tue, 26 Jun 2018 14:23:43 +0200
> Marc-André Lureau <marcandre.lureau@redhat.com> wrote:
>
>> From: Stefan Berger <stefanb@linux.vnet.ibm.com>
>>
>> The TPM Physical Presence interface consists of an ACPI part, a shared
>> memory part, and code in the firmware. Users can send messages to the
>> firmware by writing a code into the shared memory through invoking the
>> ACPI code. When a reboot happens, the firmware looks for the code and
>> acts on it by sending sequences of commands to the TPM.
>>
>> This patch adds the ACPI code. It is similar to the one in EDK2 but doesn't
>> assume that SMIs are necessary to use. It uses a similar datastructure for
>> the shared memory as EDK2 does so that EDK2 and SeaBIOS could both make use
>> of it. I extended the shared memory data structure with an array of 256
>> bytes, one for each code that could be implemented. The array contains
>> flags describing the individual codes. This decouples the ACPI implementation
>> from the firmware implementation.
>>
>> The underlying TCG specification is accessible from the following page.
>>
>> https://trustedcomputinggroup.org/tcg-physical-presence-interface-specification/
>>
>> This patch implements version 1.30.
> I've made several suggestions below how to improve aml part of patch a bit,
> will review v6 once it's done
> /hopefully it would be more readable, considering that ASM language is horrible to begin with/
>
>> Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
>>
>> ---
>>
>> v6:
>> - more code documentation (Marc-André)
>> - use some explicit named variables to ease reading (Marc-André)
>> - use fixed size fields/memory regions, remove PPI struct (Marc-André)
>> - only add PPI ACPI methods if PPI is enabled (Marc-André)
>> - document the qemu/firmware ACPI memory region (Stefan)
>>
>> v5 (Marc-André):
>> - /struct tpm_ppi/struct TPMPPIData
>>
>> v4 (Marc-André):
>> - replace 'DerefOf (FUNC [N])' with a function, to fix Windows ACPI
>> handling.
>> - replace 'return Package (..) {} ' with scoped variables, to fix
>> Windows ACPI handling.
>>
>> v3:
>> - add support for PPI to CRB
>> - split up OperationRegion TPPI into two parts, one containing
>> the registers (TPP1) and the other one the flags (TPP2); switched
>> the order of the flags versus registers in the code
>> - adapted ACPI code to small changes to the array of flags where
>> previous flag 0 was removed and now shifting right wasn't always
>> necessary anymore
>>
>> v2:
>> - get rid of FAIL variable; function 5 was using it and always
>> returns 0; the value is related to the ACPI function call not
>> a possible failure of the TPM function call.
>> - extend shared memory data structure with per-opcode entries
>> holding flags and use those flags to determine what to return
>> to caller
>> - implement interface version 1.3
>> ---
>> include/hw/acpi/tpm.h | 8 +
>> hw/i386/acpi-build.c | 423 +++++++++++++++++++++++++++++++++++++++++-
>> docs/specs/tpm.txt | 79 ++++++++
>> 3 files changed, 509 insertions(+), 1 deletion(-)
>>
>> diff --git a/include/hw/acpi/tpm.h b/include/hw/acpi/tpm.h
>> index f79d68a77a..e0bd07862e 100644
>> --- a/include/hw/acpi/tpm.h
>> +++ b/include/hw/acpi/tpm.h
>> @@ -196,4 +196,12 @@ REG32(CRB_DATA_BUFFER, 0x80)
>> #define TPM_PPI_VERSION_NONE 0
>> #define TPM_PPI_VERSION_1_30 1
>>
>> +/* whether function is blocked by BIOS settings; bits 0, 1, 2 */
>> +#define TPM_PPI_FUNC_NOT_IMPLEMENTED (0 << 0)
>> +#define TPM_PPI_FUNC_BIOS_ONLY (1 << 0)
>> +#define TPM_PPI_FUNC_BLOCKED (2 << 0)
>> +#define TPM_PPI_FUNC_ALLOWED_USR_REQ (3 << 0)
>> +#define TPM_PPI_FUNC_ALLOWED_USR_NOT_REQ (4 << 0)
>> +#define TPM_PPI_FUNC_MASK (7 << 0)
>> +
>> #endif /* HW_ACPI_TPM_H */
>> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
>> index d9320845ed..d815af4eef 100644
>> --- a/hw/i386/acpi-build.c
>> +++ b/hw/i386/acpi-build.c
>> @@ -43,6 +43,7 @@
>> #include "hw/acpi/memory_hotplug.h"
>> #include "sysemu/tpm.h"
>> #include "hw/acpi/tpm.h"
>> +#include "hw/tpm/tpm_ppi.h"
>> #include "hw/acpi/vmgenid.h"
>> #include "sysemu/tpm_backend.h"
>> #include "hw/timer/mc146818rtc_regs.h"
>> @@ -1789,6 +1790,421 @@ static Aml *build_q35_osc_method(void)
>> return method;
>> }
>>
>> +static void
>> +build_tpm_ppi(Aml *dev)
>> +{
>> + Aml *method, *name, *field, *ifctx, *ifctx2, *ifctx3, *pak;
>> + int i;
>> +
>> + if (!object_property_get_bool(OBJECT(tpm_find()), "ppi", &error_abort)) {
> if tpm_find() == NULL -> BAAM???
This function wouldn't be called if there's no TPM.
On Wed, 27 Jun 2018 10:06:18 -0400
Stefan Berger <stefanb@linux.vnet.ibm.com> wrote:
> On 06/27/2018 09:19 AM, Igor Mammedov wrote:
> > On Tue, 26 Jun 2018 14:23:43 +0200
> > Marc-André Lureau <marcandre.lureau@redhat.com> wrote:
> >
> >> From: Stefan Berger <stefanb@linux.vnet.ibm.com>
> >>
> >> The TPM Physical Presence interface consists of an ACPI part, a shared
> >> memory part, and code in the firmware. Users can send messages to the
> >> firmware by writing a code into the shared memory through invoking the
> >> ACPI code. When a reboot happens, the firmware looks for the code and
> >> acts on it by sending sequences of commands to the TPM.
> >>
> >> This patch adds the ACPI code. It is similar to the one in EDK2 but doesn't
> >> assume that SMIs are necessary to use. It uses a similar datastructure for
> >> the shared memory as EDK2 does so that EDK2 and SeaBIOS could both make use
> >> of it. I extended the shared memory data structure with an array of 256
> >> bytes, one for each code that could be implemented. The array contains
> >> flags describing the individual codes. This decouples the ACPI implementation
> >> from the firmware implementation.
> >>
> >> The underlying TCG specification is accessible from the following page.
> >>
> >> https://trustedcomputinggroup.org/tcg-physical-presence-interface-specification/
> >>
> >> This patch implements version 1.30.
> > I've made several suggestions below how to improve aml part of patch a bit,
> > will review v6 once it's done
> > /hopefully it would be more readable, considering that ASM language is horrible to begin with/
> >
> >> Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
> >>
> >> ---
> >>
> >> v6:
> >> - more code documentation (Marc-André)
> >> - use some explicit named variables to ease reading (Marc-André)
> >> - use fixed size fields/memory regions, remove PPI struct (Marc-André)
> >> - only add PPI ACPI methods if PPI is enabled (Marc-André)
> >> - document the qemu/firmware ACPI memory region (Stefan)
> >>
> >> v5 (Marc-André):
> >> - /struct tpm_ppi/struct TPMPPIData
> >>
> >> v4 (Marc-André):
> >> - replace 'DerefOf (FUNC [N])' with a function, to fix Windows ACPI
> >> handling.
> >> - replace 'return Package (..) {} ' with scoped variables, to fix
> >> Windows ACPI handling.
> >>
> >> v3:
> >> - add support for PPI to CRB
> >> - split up OperationRegion TPPI into two parts, one containing
> >> the registers (TPP1) and the other one the flags (TPP2); switched
> >> the order of the flags versus registers in the code
> >> - adapted ACPI code to small changes to the array of flags where
> >> previous flag 0 was removed and now shifting right wasn't always
> >> necessary anymore
> >>
> >> v2:
> >> - get rid of FAIL variable; function 5 was using it and always
> >> returns 0; the value is related to the ACPI function call not
> >> a possible failure of the TPM function call.
> >> - extend shared memory data structure with per-opcode entries
> >> holding flags and use those flags to determine what to return
> >> to caller
> >> - implement interface version 1.3
> >> ---
> >> include/hw/acpi/tpm.h | 8 +
> >> hw/i386/acpi-build.c | 423 +++++++++++++++++++++++++++++++++++++++++-
> >> docs/specs/tpm.txt | 79 ++++++++
> >> 3 files changed, 509 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/include/hw/acpi/tpm.h b/include/hw/acpi/tpm.h
> >> index f79d68a77a..e0bd07862e 100644
> >> --- a/include/hw/acpi/tpm.h
> >> +++ b/include/hw/acpi/tpm.h
> >> @@ -196,4 +196,12 @@ REG32(CRB_DATA_BUFFER, 0x80)
> >> #define TPM_PPI_VERSION_NONE 0
> >> #define TPM_PPI_VERSION_1_30 1
> >>
> >> +/* whether function is blocked by BIOS settings; bits 0, 1, 2 */
> >> +#define TPM_PPI_FUNC_NOT_IMPLEMENTED (0 << 0)
> >> +#define TPM_PPI_FUNC_BIOS_ONLY (1 << 0)
> >> +#define TPM_PPI_FUNC_BLOCKED (2 << 0)
> >> +#define TPM_PPI_FUNC_ALLOWED_USR_REQ (3 << 0)
> >> +#define TPM_PPI_FUNC_ALLOWED_USR_NOT_REQ (4 << 0)
> >> +#define TPM_PPI_FUNC_MASK (7 << 0)
> >> +
> >> #endif /* HW_ACPI_TPM_H */
> >> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> >> index d9320845ed..d815af4eef 100644
> >> --- a/hw/i386/acpi-build.c
> >> +++ b/hw/i386/acpi-build.c
> >> @@ -43,6 +43,7 @@
> >> #include "hw/acpi/memory_hotplug.h"
> >> #include "sysemu/tpm.h"
> >> #include "hw/acpi/tpm.h"
> >> +#include "hw/tpm/tpm_ppi.h"
> >> #include "hw/acpi/vmgenid.h"
> >> #include "sysemu/tpm_backend.h"
> >> #include "hw/timer/mc146818rtc_regs.h"
> >> @@ -1789,6 +1790,421 @@ static Aml *build_q35_osc_method(void)
> >> return method;
> >> }
> >>
> >> +static void
> >> +build_tpm_ppi(Aml *dev)
> >> +{
> >> + Aml *method, *name, *field, *ifctx, *ifctx2, *ifctx3, *pak;
> >> + int i;
> >> +
> >> + if (!object_property_get_bool(OBJECT(tpm_find()), "ppi", &error_abort)) {
> > if tpm_find() == NULL -> BAAM???
>
> This function wouldn't be called if there's no TPM.
it happens not to be called now,
I'd suggest do look up once (QOM tree walk expensive)
and pass found value as an argument down call chain.
Hi
On Wed, Jun 27, 2018 at 3:19 PM, Igor Mammedov <imammedo@redhat.com> wrote:
> On Tue, 26 Jun 2018 14:23:43 +0200
> Marc-André Lureau <marcandre.lureau@redhat.com> wrote:
>
>> From: Stefan Berger <stefanb@linux.vnet.ibm.com>
>>
>> The TPM Physical Presence interface consists of an ACPI part, a shared
>> memory part, and code in the firmware. Users can send messages to the
>> firmware by writing a code into the shared memory through invoking the
>> ACPI code. When a reboot happens, the firmware looks for the code and
>> acts on it by sending sequences of commands to the TPM.
>>
>> This patch adds the ACPI code. It is similar to the one in EDK2 but doesn't
>> assume that SMIs are necessary to use. It uses a similar datastructure for
>> the shared memory as EDK2 does so that EDK2 and SeaBIOS could both make use
>> of it. I extended the shared memory data structure with an array of 256
>> bytes, one for each code that could be implemented. The array contains
>> flags describing the individual codes. This decouples the ACPI implementation
>> from the firmware implementation.
>>
>> The underlying TCG specification is accessible from the following page.
>>
>> https://trustedcomputinggroup.org/tcg-physical-presence-interface-specification/
>>
>> This patch implements version 1.30.
>
> I've made several suggestions below how to improve aml part of patch a bit,
> will review v6 once it's done
> /hopefully it would be more readable, considering that ASM language is horrible to begin with/
>
>>
>> Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
>>
>> ---
>>
>> v6:
>> - more code documentation (Marc-André)
>> - use some explicit named variables to ease reading (Marc-André)
>> - use fixed size fields/memory regions, remove PPI struct (Marc-André)
>> - only add PPI ACPI methods if PPI is enabled (Marc-André)
>> - document the qemu/firmware ACPI memory region (Stefan)
>>
>> v5 (Marc-André):
>> - /struct tpm_ppi/struct TPMPPIData
>>
>> v4 (Marc-André):
>> - replace 'DerefOf (FUNC [N])' with a function, to fix Windows ACPI
>> handling.
>> - replace 'return Package (..) {} ' with scoped variables, to fix
>> Windows ACPI handling.
>>
>> v3:
>> - add support for PPI to CRB
>> - split up OperationRegion TPPI into two parts, one containing
>> the registers (TPP1) and the other one the flags (TPP2); switched
>> the order of the flags versus registers in the code
>> - adapted ACPI code to small changes to the array of flags where
>> previous flag 0 was removed and now shifting right wasn't always
>> necessary anymore
>>
>> v2:
>> - get rid of FAIL variable; function 5 was using it and always
>> returns 0; the value is related to the ACPI function call not
>> a possible failure of the TPM function call.
>> - extend shared memory data structure with per-opcode entries
>> holding flags and use those flags to determine what to return
>> to caller
>> - implement interface version 1.3
>> ---
>> include/hw/acpi/tpm.h | 8 +
>> hw/i386/acpi-build.c | 423 +++++++++++++++++++++++++++++++++++++++++-
>> docs/specs/tpm.txt | 79 ++++++++
>> 3 files changed, 509 insertions(+), 1 deletion(-)
>>
>> diff --git a/include/hw/acpi/tpm.h b/include/hw/acpi/tpm.h
>> index f79d68a77a..e0bd07862e 100644
>> --- a/include/hw/acpi/tpm.h
>> +++ b/include/hw/acpi/tpm.h
>> @@ -196,4 +196,12 @@ REG32(CRB_DATA_BUFFER, 0x80)
>> #define TPM_PPI_VERSION_NONE 0
>> #define TPM_PPI_VERSION_1_30 1
>>
>> +/* whether function is blocked by BIOS settings; bits 0, 1, 2 */
>> +#define TPM_PPI_FUNC_NOT_IMPLEMENTED (0 << 0)
>> +#define TPM_PPI_FUNC_BIOS_ONLY (1 << 0)
>> +#define TPM_PPI_FUNC_BLOCKED (2 << 0)
>> +#define TPM_PPI_FUNC_ALLOWED_USR_REQ (3 << 0)
>> +#define TPM_PPI_FUNC_ALLOWED_USR_NOT_REQ (4 << 0)
>> +#define TPM_PPI_FUNC_MASK (7 << 0)
>> +
>> #endif /* HW_ACPI_TPM_H */
>> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
>> index d9320845ed..d815af4eef 100644
>> --- a/hw/i386/acpi-build.c
>> +++ b/hw/i386/acpi-build.c
>> @@ -43,6 +43,7 @@
>> #include "hw/acpi/memory_hotplug.h"
>> #include "sysemu/tpm.h"
>> #include "hw/acpi/tpm.h"
>> +#include "hw/tpm/tpm_ppi.h"
>> #include "hw/acpi/vmgenid.h"
>> #include "sysemu/tpm_backend.h"
>> #include "hw/timer/mc146818rtc_regs.h"
>> @@ -1789,6 +1790,421 @@ static Aml *build_q35_osc_method(void)
>> return method;
>> }
>>
>> +static void
>> +build_tpm_ppi(Aml *dev)
>> +{
>> + Aml *method, *name, *field, *ifctx, *ifctx2, *ifctx3, *pak;
>> + int i;
>> +
>> + if (!object_property_get_bool(OBJECT(tpm_find()), "ppi", &error_abort)) {
> if tpm_find() == NULL -> BAAM???
>
> I'd do it like this:
> tmp = tpm_find()
> if (TPM_IS_TIS(tpm) {
> ...
> if (object_property_get_bool(tpm), "ppi", &error_abort)) {
> build_tpm_ppi(tpm, dev)
> }
> ...
> }
>
> if (TPM_IS_CRB(tpm))
> {
> ....
> }
>
> a bit more verbose but then the reader won't have to jump inside of
> build_tpm_ppi() if he/she is not interested in it.
ok, I pass the tpm to build_tpm_ppi() for the ppi property check, and
avoid extra lookup.
>
>> + return;
>> + }
>> + /*
>> + * TPP1 is for the flags that indicate which PPI operations
>> + * are supported by the firmware. The firmware is expected to
>> + * write these flags.
>> + */
>> + aml_append(dev,
>> + aml_operation_region("TPP1", AML_SYSTEM_MEMORY,
>> + aml_int(TPM_PPI_ADDR_BASE), 0x100));
>> + field = aml_field("TPP1", AML_ANY_ACC, AML_NOLOCK, AML_PRESERVE);
>> + for (i = 0; i < 0x100; i++) {
>> + char *tmp = g_strdup_printf("FN%02X", i);
>> + aml_append(field, aml_named_field(tmp, 8));
>> + g_free(tmp);
>> + }
>> + aml_append(dev, field);
>> +
>> + /*
>> + * TPP2 is for the registers that ACPI code used to pass
>> + * the PPI code and parameter (PPRQ, PPRM) to the firmware.
>> + */
>> + aml_append(dev,
>> + aml_operation_region("TPP2", AML_SYSTEM_MEMORY,
>> + aml_int(TPM_PPI_ADDR_BASE + 0x100),
>> + 0x5A));
>> + field = aml_field("TPP2", AML_ANY_ACC, AML_NOLOCK, AML_PRESERVE);
>> + aml_append(field, aml_named_field("PPIN", 8));
>> + aml_append(field, aml_named_field("PPIP", 32));
>> + aml_append(field, aml_named_field("PPRP", 32));
>> + aml_append(field, aml_named_field("PPRQ", 32));
>> + aml_append(field, aml_named_field("PPRM", 32));
>> + aml_append(field, aml_named_field("LPPR", 32));
>> + aml_append(dev, field);
>> +
>> + /*
>> + * A function to return the value of DerefOf (FUNC [N]), by using
>> + * accessing the fields individually instead. This is a workaround
>> + * for what looks like a Windows ACPI bug in all versions so far
>> + * (fwiw, DerefOf (FUNC [N]) works on Linux).
>> + */
>> + method = aml_method("TPFN", 1, AML_SERIALIZED);
>> + {
>> + for (i = 0; i < 0x100; i++) {
>> + ifctx = aml_if(aml_equal(aml_int(i), aml_arg(0)));
>> + {
>> + aml_append(ifctx, aml_return(aml_name("FN%02X", i)));
>> + }
>> + aml_append(method, ifctx);
>> + }
>> + aml_append(method, aml_return(aml_int(0)));
>> + }
>> + aml_append(dev, method);
>> +
>> + pak = aml_package(2);
>> + aml_append(pak, aml_int(0));
>> + aml_append(pak, aml_int(0));
>> + name = aml_name_decl("TPM2", pak);
>> + aml_append(dev, name);
>> +
>> + pak = aml_package(3);
>> + aml_append(pak, aml_int(0));
>> + aml_append(pak, aml_int(0));
>> + aml_append(pak, aml_int(0));
>> + name = aml_name_decl("TPM3", pak);
> Aml one = aml_int(1)
> Aml tpm3 = local(x)
> aml_store(pak, tpm3)
>
> ... and then later ...
>
> {
> /* TPM2[1] = PPRQ */
> aml_append(ifctx3, aml_store(aml_name("PPRQ"), aml_index(tpm2, one)));
> aml_append(ifctx3, aml_return(tpm2));
>
> which would make code a bit more readable
>
But you would have to create aml_int(), aml_local() for every usage. I
don't think we gain in readability.
>> + aml_append(dev, name);
> both packages could be local vars as return is done by value
>
>> +
>> + method = aml_method("_DSM", 4, AML_SERIALIZED);
>> + {
>> + uint8_t zerobyte[1] = { 0 };
>> + Aml *func_idx, *rev, *op, *op_arg, *op_flags;
>> +
>> + ifctx = aml_if(
>> + aml_equal(aml_arg(0),
>> + aml_touuid("3DDDFAA6-361B-4EB4-A424-8D10089D1653")));
> aml_equal(uuid, aml_touuid("3DDDFAA6-361B-4EB4-A424-8D10089D1653"))
Ok
>
>> + {
>> + func_idx = aml_local(0);
>> + aml_append(ifctx,
>> + aml_store(aml_to_integer(aml_arg(2)), func_idx));
> why do you need aml_to_integer() cast here?
>
> Wouldn't following just work:
>
> Aml function = aml_arg(2)
>
> I'd suggest to use "function" for consistency with nvdimm _DSM
ok
>
> you can use the same naming approach for other arguments i.e.
> arguments = aml_arg(3)
>
ok
>> +
>> + /* standard DSM query function */
>> + func_idx = aml_local(0);
> I don't think you need to init it twice.
>
That looks right, and it's the way nvdimm ACPI code is written, but is
not following the usual convention to give up the ownership when given
as argument to other AML building function.
Sad we don't stick to a single usage pattern (giving up ownership).
Some day, someone will look at fixing the leaks, and that may make its
work easier if the code was consistent...
But I'll follow your advise for now.
>> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(0)));
>> + {
>> + uint8_t byte_list[2] = { 0xff, 0x01 };
>> + aml_append(ifctx2, aml_return(aml_buffer(2, byte_list)));
>> + }
>> + aml_append(ifctx, ifctx2);
>> +
>> + /*
>> + * 8.1.1 Get Physical Presence Interface Version
> like Michael noted use version/chapter pair to as reference
>
> ex: /* ACPI 1.0b: 16.2.5.2 Named Objects Encoding: DefOpRegion */
ok
>
>> + *
>> + * Arg 2 (Integer): Function Index = 1
>> + * Arg 3 (Package): Arguments = Empty Package
>> + * Returns: Type: String
>> + */
>> + func_idx = aml_local(0);
> not needed
>
>> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(1)));
>> + {
>> + aml_append(ifctx2, aml_return(aml_string("1.3")));
>> + }
>> + aml_append(ifctx, ifctx2);
>> +
>> + /*
>> + * 8.1.2 Submit TPM Operation Request to Pre-OS Environment
>> + *
>> + * Arg 2 (Integer): Function Index = 2
>> + * Arg 3 (Package): Arguments = Package: Type: Integer
>> + * Operation Value of the Request
>> + * Returns: Type: Integer
>> + * 0: Success
>> + * 1: Operation Value of the Request Not Supported
>> + * 2: General Failure
>> + */
>> + func_idx = aml_local(0);
> ditto and the same in other places
>
>> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(2)));
>> + {
>> + /* get opcode */
>> + op = aml_derefof(aml_index(aml_arg(3), aml_int(0)));
>> + aml_append(ifctx2, aml_store(op, aml_local(0)));
> ^^^ what this local(0) is? suggest to use named var here (in C sense)
>> +
>> + /* get opcode flags */
>> + op = aml_local(0);
> use other local to make ASL less confusion (i.e. try not to reuse local vars for something else)
I must say I get a bit confused by the code style change you request.
The original code from Stefan was more straightforward to me. Now it
seems C variables adds another layer of complexity. I think it's
easier if you come up with a follow-up patch for further cleanup
iterations, as I find it hard to match your wanted style.
>> + aml_append(ifctx2,
>> + aml_store(aml_call1("TPFN", op), aml_local(1)));
> ^^^ what this local(1) is?
>
>> +
>> + op_flags = aml_local(1);
> I'd init all named vars at the top of function where it's easy to see what is what
> and use them later. ex: nvdimm_build_common_dsm()
But the arguments depend on the function.
>
>> + /* if func[opcode] & TPM_PPI_FUNC_NOT_IMPLEMENTED */
>> + ifctx3 = aml_if(
>> + aml_equal(
>> + aml_and(op_flags, aml_int(TPM_PPI_FUNC_MASK), NULL),
>> + aml_int(TPM_PPI_FUNC_NOT_IMPLEMENTED)));
>> + {
>> + /* 1: not implemented */
> may be the same language as in above comment
> /* 1: Operation Value of the Request Not Supported */
> same applies to other return values
ok
>
>> + aml_append(ifctx3, aml_return(aml_int(1)));
>> + }
>> + aml_append(ifctx2, ifctx3);
>> +
>> + op = aml_local(0);
>> + aml_append(ifctx2, aml_store(op, aml_name("PPRQ")));
>> + aml_append(ifctx2, aml_store(aml_int(0), aml_name("PPRM")));
>> + /* 0: success */
>> + aml_append(ifctx2, aml_return(aml_int(0)));
>> + }
>> + aml_append(ifctx, ifctx2);
>> +
>> + /*
>> + * 8.1.3 Get Pending TPM Operation Requested By the OS
>> + *
>> + * Arg 2 (Integer): Function Index = 3
>> + * Arg 3 (Package): Arguments = Empty Package
>> + * Returns: Type: Package of Integers
>> + * Integer 1: Function Return code
>> + * 0: Success
>> + * 1: General Failure
>> + * Integer 2: Pending operation requested by the OS
>> + * 0: None
>> + * >0: Operation Value of the Pending Request
>> + * Integer 3: Optional argument to pending operation
>> + * requested by the OS
>> + * 0: None
>> + * >0: Argument Value of the Pending Request
>> + */
>> + func_idx = aml_local(0);
>> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(3)));
>> + {
>> + /* revision to integer */
>> + aml_append(ifctx2,
>> + aml_store(
>> + aml_to_integer(aml_arg(1)),
> same do you need cast here, by spec it's 'int' already?
>
Yeah, looks like it's unnecessary. Stefan?
>> + aml_local(1)));
> why store into local var, couldn't it be used directly ?
removed
>
>> + /*
>> + * Revision ID of 1, no integer parameter beyond
>> + * parameter two are expected
>> + */
>> + rev = aml_local(1);
>> + ifctx3 = aml_if(aml_equal(rev, aml_int(1)));
>> + {
>> + /* TPM2[1] = PPRQ */
>> + aml_append(ifctx3,
>> + aml_store(
>> + aml_name("PPRQ"),
>> + aml_index(aml_name("TPM2"), aml_int(1))));
>> + aml_append(ifctx3, aml_return(aml_name("TPM2")));
>> + }
>> + aml_append(ifctx2, ifctx3);
>> +
>> + /*
>> + * A return value of {0, 23, 1} indicates that
>> + * operation 23 with argument 1 is pending.
>> + */
>> + rev = aml_local(1);
>> + ifctx3 = aml_if(aml_equal(rev, aml_int(2)));
>> + {
>> + /* TPM3[1] = PPRQ */
>> + aml_append(ifctx3,
>> + aml_store(
>> + aml_name("PPRQ"),
>> + aml_index(aml_name("TPM3"), aml_int(1))));
>> + /* TPM3[2] = PPRM */
>> + aml_append(ifctx3,
>> + aml_store(
>> + aml_name("PPRM"),
>> + aml_index(aml_name("TPM3"), aml_int(2))));
>> + aml_append(ifctx3, aml_return(aml_name("TPM3")));
>> + }
>> + aml_append(ifctx2, ifctx3);
>> + }
>> + aml_append(ifctx, ifctx2);
>> +
>> + /*
>> + * 8.1.4 Get Platform-Specific Action to Transition to
>> + * Pre-OS Environment
>> + *
>> + * Arg 2 (Integer): Function Index = 4
>> + * Arg 3 (Package): Arguments = Empty Package
>> + * Returns: Type: Integer
>> + * 0: None
>> + * 1: Shutdown
>> + * 2: Reboot
>> + * 3: OS Vendor-specific
>> + */
>> + func_idx = aml_local(0);
>> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(4)));
>> + {
>> + /* reboot */
>> + aml_append(ifctx2, aml_return(aml_int(2)));
>> + }
>> + aml_append(ifctx, ifctx2);
>> +
>> + /*
>> + * 8.1.5 Return TPM Operation Response to OS Environment
>> + *
>> + * Arg 2 (Integer): Function Index = 5
>> + * Arg 3 (Package): Arguments = Empty Package
>> + * Returns: Type: Package of Integer
>> + * Integer 1: Function Return code
>> + * 0: Success
>> + * 1: General Failure
>> + * Integer 2: Most recent operation request
>> + * 0: None
>> + * >0: Operation Value of the most recent request
>> + * Integer 3: Response to the most recent operation request
>> + * 0: Success
>> + * 0x00000001..0x00000FFF: Corresponding TPM
>> + * error code
>> + * 0xFFFFFFF0: User Abort or timeout of dialog
>> + * 0xFFFFFFF1: firmware Failure
>> + */
>> + func_idx = aml_local(0);
>> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(5)));
>> + {
>> + /* TPM3[1] = LPPR */
>> + aml_append(ifctx2,
>> + aml_store(
>> + aml_name("LPPR"),
>> + aml_index(aml_name("TPM3"), aml_int(1))));
>> + /* TPM3[2] = PPRP */
>> + aml_append(ifctx2,
>> + aml_store(
>> + aml_name("PPRP"),
>> + aml_index(aml_name("TPM3"), aml_int(2))));
>> + aml_append(ifctx2, aml_return(aml_name("TPM3")));
>> + }
>> + aml_append(ifctx, ifctx2);
>> +
>> + /*
>> + * 8.1.6 Submit preferred user language
>> + *
>> + * Arg 2 (Integer): Function Index = 6
>> + * Arg 3 (Package): Arguments = String Package
>> + * Preferred language code
>> + * Returns: Type: Integer
>> + * Function Return Code
>> + * 3: Not implemented
>> + */
>> + func_idx = aml_local(0);
>> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(6)));
>> + {
>> + /* 3 = not implemented */
>> + aml_append(ifctx2, aml_return(aml_int(3)));
>> + }
>> + aml_append(ifctx, ifctx2);
>> +
>> + /*
>> + * 8.1.7 Submit TPM Operation Request to Pre-OS Environment 2
>> + *
>> + * Arg 2 (Integer): Function Index = 7
>> + * Arg 3 (Package): Arguments = Package: Type: Integer
>> + * Integer 1: Operation Value of the Request
>> + * Integer 2: Argument for Operation (optional)
>> + * Returns: Type: Integer
>> + * 0: Success
>> + * 1: Not Implemented
>> + * 2: General Failure
>> + * 3: Operation blocked by current firmware settings
>> + */
>> + func_idx = aml_local(0);
>> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(7)));
>> + {
>> + /* get opcode */
>> + op = aml_derefof(aml_index(aml_arg(3), aml_int(0)));
>> + aml_append(ifctx2, aml_store(op, aml_local(0)));
>> +
>> + /* get opcode flags */
>> + op = aml_local(0);
>> + aml_append(ifctx2, aml_store(aml_call1("TPFN", op),
>> + aml_local(1)));
>> + /* if func[opcode] & TPM_PPI_FUNC_NOT_IMPLEMENTED */
>> + op_flags = aml_local(1);
>> + ifctx3 = aml_if(
>> + aml_equal(
>> + aml_and(op_flags, aml_int(TPM_PPI_FUNC_MASK), NULL),
>> + aml_int(TPM_PPI_FUNC_NOT_IMPLEMENTED)));
>> + {
>> + /* 1: not implemented */
>> + aml_append(ifctx3, aml_return(aml_int(1)));
>> + }
>> + aml_append(ifctx2, ifctx3);
>> +
>> + /* if func[opcode] & TPM_PPI_FUNC_BLOCKED */
>> + op_flags = aml_local(1);
>> + ifctx3 = aml_if(
>> + aml_equal(
>> + aml_and(op_flags, aml_int(TPM_PPI_FUNC_MASK), NULL),
>> + aml_int(TPM_PPI_FUNC_BLOCKED)));
>> + {
>> + /* 3: blocked by firmware */
>> + aml_append(ifctx3, aml_return(aml_int(3)));
>> + }
>> + aml_append(ifctx2, ifctx3);
>> +
>> + /* revision to integer */
>> + aml_append(ifctx2,
>> + aml_store(
>> + aml_to_integer(aml_arg(1)),
>> + aml_local(1)));
>> +
>> + rev = aml_local(1);
>> + ifctx3 = aml_if(aml_equal(rev, aml_int(1)));
>> + {
>> + /* revision 1 */
>> + /* PPRQ = op */
>> + op = aml_local(0);
>> + aml_append(ifctx3, aml_store(op, aml_name("PPRQ")));
>> + /* no argument, PPRM = 0 */
>> + aml_append(ifctx3, aml_store(aml_int(0),
>> + aml_name("PPRM")));
>> + }
>> + aml_append(ifctx2, ifctx3);
>> +
>> + rev = aml_local(1);
>> + ifctx3 = aml_if(aml_equal(rev, aml_int(2)));
>> + {
>> + /* revision 2 */
>> + /* PPRQ = op */
>> + op = aml_local(0);
>> + op_arg = aml_derefof(aml_index(aml_arg(3), aml_int(1)));
>> + aml_append(ifctx3, aml_store(op, aml_name("PPRQ")));
>> + /* PPRM = arg3[1] */
>> + aml_append(ifctx3, aml_store(op_arg, aml_name("PPRM")));
>> + }
>> + aml_append(ifctx2, ifctx3);
>> + /* 0: success */
>> + aml_append(ifctx2, aml_return(aml_int(0)));
>> + }
>> + aml_append(ifctx, ifctx2);
>> +
>> + /*
>> + * 8.1.8 Get User Confirmation Status for Operation
>> + *
>> + * Arg 2 (Integer): Function Index = 8
>> + * Arg 3 (Package): Arguments = Package: Type: Integer
>> + * Operation Value that may need user confirmation
>> + * Returns: Type: Integer
>> + * 0: Not implemented
>> + * 1: Firmware only
>> + * 2: Blocked for OS by firmware configuration
>> + * 3: Allowed and physically present user required
>> + * 4: Allowed and physically present user not required
>> + */
>> + func_idx = aml_local(0);
>> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(8)));
>> + {
>> + /* get opcode */
>> + op = aml_derefof(aml_index(aml_arg(3), aml_int(0)));
>> + aml_append(ifctx2, aml_store(op, aml_local(0)));
>> +
>> + /* get opcode flags */
>> + op = aml_local(0);
>> + aml_append(ifctx2, aml_store(aml_call1("TPFN", op),
>> + aml_local(1)));
>> + op_flags = aml_local(1);
>> + /* return confirmation status code */
>> + aml_append(ifctx2,
>> + aml_return(
>> + aml_and(op_flags,
>> + aml_int(TPM_PPI_FUNC_MASK), NULL)));
>> + }
>> + aml_append(ifctx, ifctx2);
>> +
>> + aml_append(ifctx, aml_return(aml_buffer(1, zerobyte)));
>> + }
>> + aml_append(method, ifctx);
>> + }
>> + aml_append(dev, method);
>> +}
>> +
>> static void
>> build_dsdt(GArray *table_data, BIOSLinker *linker,
>> AcpiPmInfo *pm, AcpiMiscInfo *misc,
>> @@ -2153,6 +2569,9 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
>> */
>> /* aml_append(crs, aml_irq_no_flags(TPM_TIS_IRQ)); */
>> aml_append(dev, aml_name_decl("_CRS", crs));
>> +
>> + build_tpm_ppi(dev);
>> +
>> aml_append(scope, dev);
>> }
>>
>> @@ -2172,6 +2591,8 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
>> aml_append(method, aml_return(aml_int(0x0f)));
>> aml_append(dev, method);
>>
>> + build_tpm_ppi(dev);
>> +
>> aml_append(sb_scope, dev);
>> }
>>
>> @@ -2920,7 +3341,7 @@ void acpi_setup(void)
>> tpm_config = (FWCfgTPMConfig) {
>> .tpmppi_address = cpu_to_le32(TPM_PPI_ADDR_BASE),
>> .tpm_version = cpu_to_le32(tpm_get_version(tpm_find())),
>> - .tpmppi_version = cpu_to_le32(TPM_PPI_VERSION_NONE)
>> + .tpmppi_version = cpu_to_le32(TPM_PPI_VERSION_1_30)
> s/cpu_to_le32//
ok
>
>> };
>> fw_cfg_add_file(pcms->fw_cfg, "etc/tpm/config",
>> &tpm_config, sizeof tpm_config);
>> diff --git a/docs/specs/tpm.txt b/docs/specs/tpm.txt
>> index 2ddb768084..c27762c723 100644
>> --- a/docs/specs/tpm.txt
>> +++ b/docs/specs/tpm.txt
>> @@ -62,6 +62,85 @@ URL:
>>
>> https://trustedcomputinggroup.org/tcg-acpi-specification/
>>
>> +== ACPI PPI Interface ==
>> +
>> +QEMU supports the Physical Presence Interface (PPI) for TPM 1.2 and TPM 2. This
>> +interface requires ACPI and firmware support. The specification can be found at
>> +the following URL:
>> +
>> +https://trustedcomputinggroup.org/resource/tcg-physical-presence-interface-specification/
>> +
>> +PPI enables a system administrator (root) to request a modification to the
>> +TPM upon reboot. The PPI specification defines the operation requests and the
>> +actions the firmware has to take. The system administrator passes the operation
>> +request number to the firmware through an ACPI interface which writes this
>> +number to a memory location that the firmware knows. Upon reboot, the firmware
>> +finds the number and sends commands to the the TPM. The firmware writes the TPM
>> +result code and the operation request number to a memory location that ACPI can
>> +read from and pass the result on to the administrator.
>> +
>> +The PPI specification defines a set of mandatory and optional operations for
>> +the firmware to implement. The ACPI interface also allows an administrator to
>> +list the supported operations. In QEMU the ACPI code is generated by QEMU, yet
>> +the firmware needs to implement support on a per-operations basis, and
>> +different firmwares may support a different subset. Therefore, QEMU introduces
>> +the virtual memory device for PPI where the firmware can indicate which
>> +operations it supports and ACPI can enable the ones that are supported and
>> +disable all others. This interface lies in main memory and has the following
>> +layout:
>> +
>> + +----------+--------+--------+-------------------------------------------+
>> + | Field | Length | Offset | Description |
>> + +----------+--------+--------+-------------------------------------------+
>> + | func | 0x100 | 0x000 | Firmware sets values for each supported |
>> + | | | | operation. See defined values below. |
>> + +----------+--------+--------+-------------------------------------------+
>> + | ppin | 0x1 | 0x100 | SMI interrupt to use. Set by firmware. |
>> + | | | | Not supported. |
>> + +----------+--------+--------+-------------------------------------------+
>> + | ppip | 0x4 | 0x101 | ACPI function index to pass to SMM code. |
>> + | | | | Set by ACPI. Not supported. |
>> + +----------+--------+--------+-------------------------------------------+
>> + | pprp | 0x4 | 0x105 | Result of last executed operation. Set by |
>> + | | | | firmware. See function index 5 for values.|
>> + +----------+--------+--------+-------------------------------------------+
>> + | pprq | 0x4 | 0x109 | Operation request number to execute. See |
>> + | | | | 'Physical Presence Interface Operation |
>> + | | | | Summary' tables in specs. Set by ACPI. |
>> + +----------+--------+--------+-------------------------------------------+
>> + | pprm | 0x4 | 0x10d | Operation request optional parameter. |
>> + | | | | Values depend on operation. Set by ACPI. |
>> + +----------+--------+--------+-------------------------------------------+
>> + | lppr | 0x4 | 0x111 | Last executed operation request number. |
>> + | | | | Copied from pprq field by firmware. |
>> + +----------+--------+--------+-------------------------------------------+
>> + | fret | 0x4 | 0x115 | Result code from SMM function. |
>> + | | | | Not supported. |
>> + +----------+--------+--------+-------------------------------------------+
>> + | res1 | 0x40 | 0x119 | Reserved for future use |
>> + +----------+--------+--------+-------------------------------------------+
>> + | next_step| 0x1 | 0x159 | Operation to execute after reboot by |
>> + | | | | firmware. Used by firmware. |
>> + +----------+--------+--------+-------------------------------------------+
>> +
>> + The following values are supported for the 'func' field. They correspond
>> + to the values used by ACPI function index 8.
>> +
>> + +----------+-------------------------------------------------------------+
>> + | value | Description |
>> + +----------+-------------------------------------------------------------+
>> + | 0 | Operation is not implemented. |
>> + +----------+-------------------------------------------------------------+
>> + | 1 | Operation is only accessible through firmware. |
>> + +----------+-------------------------------------------------------------+
>> + | 2 | Operation is blocked for OS by firmware configuration. |
>> + +----------+-------------------------------------------------------------+
>> + | 3 | Operation is allowed and physically present user required. |
>> + +----------+-------------------------------------------------------------+
>> + | 4 | Operation is allowed and physically present user is not |
>> + | | required. |
>> + +----------+-------------------------------------------------------------+
>> +
>>
>> QEMU files related to TPM ACPI tables:
>> - hw/i386/acpi-build.c
>
>
--
Marc-André Lureau
On 06/28/2018 11:24 AM, Marc-André Lureau wrote:
>
>>> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(3)));
>>> + {
>>> + /* revision to integer */
>>> + aml_append(ifctx2,
>>> + aml_store(
>>> + aml_to_integer(aml_arg(1)),
>> same do you need cast here, by spec it's 'int' already?
>>
> Yeah, looks like it's unnecessary. Stefan?
Iirc some things were not working at the beginning when I wrote this
ACPI thing and one problem went away by doing this cast, though it may
have overlapped with other issues. I cannot say for sure.
On Thu, 28 Jun 2018 17:24:47 +0200
Marc-André Lureau <marcandre.lureau@gmail.com> wrote:
> Hi
>
> On Wed, Jun 27, 2018 at 3:19 PM, Igor Mammedov <imammedo@redhat.com> wrote:
> > On Tue, 26 Jun 2018 14:23:43 +0200
> > Marc-André Lureau <marcandre.lureau@redhat.com> wrote:
> >
> >> From: Stefan Berger <stefanb@linux.vnet.ibm.com>
> >>
> >> The TPM Physical Presence interface consists of an ACPI part, a shared
> >> memory part, and code in the firmware. Users can send messages to the
> >> firmware by writing a code into the shared memory through invoking the
> >> ACPI code. When a reboot happens, the firmware looks for the code and
> >> acts on it by sending sequences of commands to the TPM.
> >>
> >> This patch adds the ACPI code. It is similar to the one in EDK2 but doesn't
> >> assume that SMIs are necessary to use. It uses a similar datastructure for
> >> the shared memory as EDK2 does so that EDK2 and SeaBIOS could both make use
> >> of it. I extended the shared memory data structure with an array of 256
> >> bytes, one for each code that could be implemented. The array contains
> >> flags describing the individual codes. This decouples the ACPI implementation
> >> from the firmware implementation.
> >>
> >> The underlying TCG specification is accessible from the following page.
> >>
> >> https://trustedcomputinggroup.org/tcg-physical-presence-interface-specification/
> >>
> >> This patch implements version 1.30.
> >
> > I've made several suggestions below how to improve aml part of patch a bit,
> > will review v6 once it's done
> > /hopefully it would be more readable, considering that ASM language is horrible to begin with/
> >
> >>
> >> Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
> >>
> >> ---
> >>
> >> v6:
> >> - more code documentation (Marc-André)
> >> - use some explicit named variables to ease reading (Marc-André)
> >> - use fixed size fields/memory regions, remove PPI struct (Marc-André)
> >> - only add PPI ACPI methods if PPI is enabled (Marc-André)
> >> - document the qemu/firmware ACPI memory region (Stefan)
> >>
> >> v5 (Marc-André):
> >> - /struct tpm_ppi/struct TPMPPIData
> >>
> >> v4 (Marc-André):
> >> - replace 'DerefOf (FUNC [N])' with a function, to fix Windows ACPI
> >> handling.
> >> - replace 'return Package (..) {} ' with scoped variables, to fix
> >> Windows ACPI handling.
> >>
> >> v3:
> >> - add support for PPI to CRB
> >> - split up OperationRegion TPPI into two parts, one containing
> >> the registers (TPP1) and the other one the flags (TPP2); switched
> >> the order of the flags versus registers in the code
> >> - adapted ACPI code to small changes to the array of flags where
> >> previous flag 0 was removed and now shifting right wasn't always
> >> necessary anymore
> >>
> >> v2:
> >> - get rid of FAIL variable; function 5 was using it and always
> >> returns 0; the value is related to the ACPI function call not
> >> a possible failure of the TPM function call.
> >> - extend shared memory data structure with per-opcode entries
> >> holding flags and use those flags to determine what to return
> >> to caller
> >> - implement interface version 1.3
> >> ---
> >> include/hw/acpi/tpm.h | 8 +
> >> hw/i386/acpi-build.c | 423 +++++++++++++++++++++++++++++++++++++++++-
> >> docs/specs/tpm.txt | 79 ++++++++
> >> 3 files changed, 509 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/include/hw/acpi/tpm.h b/include/hw/acpi/tpm.h
> >> index f79d68a77a..e0bd07862e 100644
> >> --- a/include/hw/acpi/tpm.h
> >> +++ b/include/hw/acpi/tpm.h
> >> @@ -196,4 +196,12 @@ REG32(CRB_DATA_BUFFER, 0x80)
> >> #define TPM_PPI_VERSION_NONE 0
> >> #define TPM_PPI_VERSION_1_30 1
> >>
> >> +/* whether function is blocked by BIOS settings; bits 0, 1, 2 */
> >> +#define TPM_PPI_FUNC_NOT_IMPLEMENTED (0 << 0)
> >> +#define TPM_PPI_FUNC_BIOS_ONLY (1 << 0)
> >> +#define TPM_PPI_FUNC_BLOCKED (2 << 0)
> >> +#define TPM_PPI_FUNC_ALLOWED_USR_REQ (3 << 0)
> >> +#define TPM_PPI_FUNC_ALLOWED_USR_NOT_REQ (4 << 0)
> >> +#define TPM_PPI_FUNC_MASK (7 << 0)
> >> +
> >> #endif /* HW_ACPI_TPM_H */
> >> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> >> index d9320845ed..d815af4eef 100644
> >> --- a/hw/i386/acpi-build.c
> >> +++ b/hw/i386/acpi-build.c
> >> @@ -43,6 +43,7 @@
> >> #include "hw/acpi/memory_hotplug.h"
> >> #include "sysemu/tpm.h"
> >> #include "hw/acpi/tpm.h"
> >> +#include "hw/tpm/tpm_ppi.h"
> >> #include "hw/acpi/vmgenid.h"
> >> #include "sysemu/tpm_backend.h"
> >> #include "hw/timer/mc146818rtc_regs.h"
> >> @@ -1789,6 +1790,421 @@ static Aml *build_q35_osc_method(void)
> >> return method;
> >> }
> >>
> >> +static void
> >> +build_tpm_ppi(Aml *dev)
> >> +{
> >> + Aml *method, *name, *field, *ifctx, *ifctx2, *ifctx3, *pak;
> >> + int i;
> >> +
> >> + if (!object_property_get_bool(OBJECT(tpm_find()), "ppi", &error_abort)) {
> > if tpm_find() == NULL -> BAAM???
> >
> > I'd do it like this:
> > tmp = tpm_find()
> > if (TPM_IS_TIS(tpm) {
> > ...
> > if (object_property_get_bool(tpm), "ppi", &error_abort)) {
> > build_tpm_ppi(tpm, dev)
> > }
> > ...
> > }
> >
> > if (TPM_IS_CRB(tpm))
> > {
> > ....
> > }
> >
> > a bit more verbose but then the reader won't have to jump inside of
> > build_tpm_ppi() if he/she is not interested in it.
>
> ok, I pass the tpm to build_tpm_ppi() for the ppi property check, and
> avoid extra lookup.
>
> >
> >> + return;
> >> + }
> >> + /*
> >> + * TPP1 is for the flags that indicate which PPI operations
> >> + * are supported by the firmware. The firmware is expected to
> >> + * write these flags.
> >> + */
> >> + aml_append(dev,
> >> + aml_operation_region("TPP1", AML_SYSTEM_MEMORY,
> >> + aml_int(TPM_PPI_ADDR_BASE), 0x100));
> >> + field = aml_field("TPP1", AML_ANY_ACC, AML_NOLOCK, AML_PRESERVE);
> >> + for (i = 0; i < 0x100; i++) {
> >> + char *tmp = g_strdup_printf("FN%02X", i);
> >> + aml_append(field, aml_named_field(tmp, 8));
> >> + g_free(tmp);
> >> + }
> >> + aml_append(dev, field);
> >> +
> >> + /*
> >> + * TPP2 is for the registers that ACPI code used to pass
> >> + * the PPI code and parameter (PPRQ, PPRM) to the firmware.
> >> + */
> >> + aml_append(dev,
> >> + aml_operation_region("TPP2", AML_SYSTEM_MEMORY,
> >> + aml_int(TPM_PPI_ADDR_BASE + 0x100),
> >> + 0x5A));
> >> + field = aml_field("TPP2", AML_ANY_ACC, AML_NOLOCK, AML_PRESERVE);
> >> + aml_append(field, aml_named_field("PPIN", 8));
> >> + aml_append(field, aml_named_field("PPIP", 32));
> >> + aml_append(field, aml_named_field("PPRP", 32));
> >> + aml_append(field, aml_named_field("PPRQ", 32));
> >> + aml_append(field, aml_named_field("PPRM", 32));
> >> + aml_append(field, aml_named_field("LPPR", 32));
> >> + aml_append(dev, field);
> >> +
> >> + /*
> >> + * A function to return the value of DerefOf (FUNC [N]), by using
> >> + * accessing the fields individually instead. This is a workaround
> >> + * for what looks like a Windows ACPI bug in all versions so far
> >> + * (fwiw, DerefOf (FUNC [N]) works on Linux).
> >> + */
> >> + method = aml_method("TPFN", 1, AML_SERIALIZED);
> >> + {
> >> + for (i = 0; i < 0x100; i++) {
> >> + ifctx = aml_if(aml_equal(aml_int(i), aml_arg(0)));
> >> + {
> >> + aml_append(ifctx, aml_return(aml_name("FN%02X", i)));
> >> + }
> >> + aml_append(method, ifctx);
> >> + }
> >> + aml_append(method, aml_return(aml_int(0)));
> >> + }
> >> + aml_append(dev, method);
> >> +
> >> + pak = aml_package(2);
> >> + aml_append(pak, aml_int(0));
> >> + aml_append(pak, aml_int(0));
> >> + name = aml_name_decl("TPM2", pak);
> >> + aml_append(dev, name);
> >> +
> >> + pak = aml_package(3);
> >> + aml_append(pak, aml_int(0));
> >> + aml_append(pak, aml_int(0));
> >> + aml_append(pak, aml_int(0));
> >> + name = aml_name_decl("TPM3", pak);
> > Aml one = aml_int(1)
> > Aml tpm3 = local(x)
> > aml_store(pak, tpm3)
> >
> > ... and then later ...
> >
> > {
> > /* TPM2[1] = PPRQ */
> > aml_append(ifctx3, aml_store(aml_name("PPRQ"), aml_index(tpm2, one)));
> > aml_append(ifctx3, aml_return(tpm2));
> >
> > which would make code a bit more readable
> >
>
> But you would have to create aml_int(), aml_local() for every usage. I
> don't think we gain in readability.
Aml* variables can be reused as aml_append/aml_foo copies input arguments.
Take look at build_cpus_aml() how it makes code more readable.
> >> + aml_append(dev, name);
> > both packages could be local vars as return is done by value
> >
> >> +
> >> + method = aml_method("_DSM", 4, AML_SERIALIZED);
> >> + {
> >> + uint8_t zerobyte[1] = { 0 };
> >> + Aml *func_idx, *rev, *op, *op_arg, *op_flags;
> >> +
> >> + ifctx = aml_if(
> >> + aml_equal(aml_arg(0),
> >> + aml_touuid("3DDDFAA6-361B-4EB4-A424-8D10089D1653")));
> > aml_equal(uuid, aml_touuid("3DDDFAA6-361B-4EB4-A424-8D10089D1653"))
>
> Ok
>
> >
> >> + {
> >> + func_idx = aml_local(0);
> >> + aml_append(ifctx,
> >> + aml_store(aml_to_integer(aml_arg(2)), func_idx));
> > why do you need aml_to_integer() cast here?
> >
> > Wouldn't following just work:
> >
> > Aml function = aml_arg(2)
> >
> > I'd suggest to use "function" for consistency with nvdimm _DSM
>
> ok
>
> >
> > you can use the same naming approach for other arguments i.e.
> > arguments = aml_arg(3)
> >
>
> ok
>
> >> +
> >> + /* standard DSM query function */
> >> + func_idx = aml_local(0);
> > I don't think you need to init it twice.
> >
>
> That looks right, and it's the way nvdimm ACPI code is written, but is
> not following the usual convention to give up the ownership when given
> as argument to other AML building function.
That's misunderstanding of how it works, there isn't such convention
input argument is copied into output AML element.
> Sad we don't stick to a single usage pattern (giving up ownership).
> Some day, someone will look at fixing the leaks, and that may make its
> work easier if the code was consistent...
Aml* pointers aren't leaked, see aml_alloc() which stores all allocations
into a list which is freed later by free_aml_allocator() when table
is build.
> But I'll follow your advise for now.
>
> >> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(0)));
> >> + {
> >> + uint8_t byte_list[2] = { 0xff, 0x01 };
> >> + aml_append(ifctx2, aml_return(aml_buffer(2, byte_list)));
> >> + }
> >> + aml_append(ifctx, ifctx2);
> >> +
> >> + /*
> >> + * 8.1.1 Get Physical Presence Interface Version
> > like Michael noted use version/chapter pair to as reference
> >
> > ex: /* ACPI 1.0b: 16.2.5.2 Named Objects Encoding: DefOpRegion */
>
> ok
>
> >
> >> + *
> >> + * Arg 2 (Integer): Function Index = 1
> >> + * Arg 3 (Package): Arguments = Empty Package
> >> + * Returns: Type: String
> >> + */
> >> + func_idx = aml_local(0);
> > not needed
> >
> >> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(1)));
> >> + {
> >> + aml_append(ifctx2, aml_return(aml_string("1.3")));
> >> + }
> >> + aml_append(ifctx, ifctx2);
> >> +
> >> + /*
> >> + * 8.1.2 Submit TPM Operation Request to Pre-OS Environment
> >> + *
> >> + * Arg 2 (Integer): Function Index = 2
> >> + * Arg 3 (Package): Arguments = Package: Type: Integer
> >> + * Operation Value of the Request
> >> + * Returns: Type: Integer
> >> + * 0: Success
> >> + * 1: Operation Value of the Request Not Supported
> >> + * 2: General Failure
> >> + */
> >> + func_idx = aml_local(0);
> > ditto and the same in other places
> >
> >> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(2)));
> >> + {
> >> + /* get opcode */
> >> + op = aml_derefof(aml_index(aml_arg(3), aml_int(0)));
> >> + aml_append(ifctx2, aml_store(op, aml_local(0)));
> > ^^^ what this local(0) is? suggest to use named var here (in C sense)
> >> +
> >> + /* get opcode flags */
> >> + op = aml_local(0);
> > use other local to make ASL less confusion (i.e. try not to reuse local vars for something else)
>
> I must say I get a bit confused by the code style change you request.
> The original code from Stefan was more straightforward to me. Now it
> seems C variables adds another layer of complexity. I think it's
> easier if you come up with a follow-up patch for further cleanup
> iterations, as I find it hard to match your wanted style.
Whole point of review is to merge code that doesn't need to be
rewritten later on and to show preferred style for ACPI code
so I wouldn't be the only one who knows how it is supposed to work.
Now about my original comment.
What we have in this patch:
func_idx = aml_local(0);
...
op = aml_local(0);
so resulting AML decompiled in to ASL would (re)use Local0 with different meanings
what I've suggested is:
Aml *func_idx = aml_local(0);
Aml *op = aml_local(1);
Aml *foo = aml_local(X);
where ASL would retain LocalX meaning throughout method, making it a bit readable.
> >> + aml_append(ifctx2,
> >> + aml_store(aml_call1("TPFN", op), aml_local(1)));
> > ^^^ what this local(1) is?
> >
> >> +
> >> + op_flags = aml_local(1);
> > I'd init all named vars at the top of function where it's easy to see what is what
> > and use them later. ex: nvdimm_build_common_dsm()
>
> But the arguments depend on the function.
some maybe, but
function index is common, arguments also, so one could do following:
Aml *func = aml_arg(2);
Aml *args = aml_arg(3);
without storing them in locals, and then use them within the method as necessary
> >
> >> + /* if func[opcode] & TPM_PPI_FUNC_NOT_IMPLEMENTED */
> >> + ifctx3 = aml_if(
> >> + aml_equal(
> >> + aml_and(op_flags, aml_int(TPM_PPI_FUNC_MASK), NULL),
> >> + aml_int(TPM_PPI_FUNC_NOT_IMPLEMENTED)));
> >> + {
> >> + /* 1: not implemented */
> > may be the same language as in above comment
> > /* 1: Operation Value of the Request Not Supported */
> > same applies to other return values
>
> ok
>
> >
> >> + aml_append(ifctx3, aml_return(aml_int(1)));
> >> + }
> >> + aml_append(ifctx2, ifctx3);
> >> +
> >> + op = aml_local(0);
> >> + aml_append(ifctx2, aml_store(op, aml_name("PPRQ")));
> >> + aml_append(ifctx2, aml_store(aml_int(0), aml_name("PPRM")));
> >> + /* 0: success */
> >> + aml_append(ifctx2, aml_return(aml_int(0)));
> >> + }
> >> + aml_append(ifctx, ifctx2);
> >> +
> >> + /*
> >> + * 8.1.3 Get Pending TPM Operation Requested By the OS
> >> + *
> >> + * Arg 2 (Integer): Function Index = 3
> >> + * Arg 3 (Package): Arguments = Empty Package
> >> + * Returns: Type: Package of Integers
> >> + * Integer 1: Function Return code
> >> + * 0: Success
> >> + * 1: General Failure
> >> + * Integer 2: Pending operation requested by the OS
> >> + * 0: None
> >> + * >0: Operation Value of the Pending Request
> >> + * Integer 3: Optional argument to pending operation
> >> + * requested by the OS
> >> + * 0: None
> >> + * >0: Argument Value of the Pending Request
> >> + */
> >> + func_idx = aml_local(0);
> >> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(3)));
> >> + {
> >> + /* revision to integer */
> >> + aml_append(ifctx2,
> >> + aml_store(
> >> + aml_to_integer(aml_arg(1)),
> > same do you need cast here, by spec it's 'int' already?
> >
>
> Yeah, looks like it's unnecessary. Stefan?
>
> >> + aml_local(1)));
> > why store into local var, couldn't it be used directly ?
>
> removed
>
> >
> >> + /*
> >> + * Revision ID of 1, no integer parameter beyond
> >> + * parameter two are expected
> >> + */
> >> + rev = aml_local(1);
> >> + ifctx3 = aml_if(aml_equal(rev, aml_int(1)));
> >> + {
> >> + /* TPM2[1] = PPRQ */
> >> + aml_append(ifctx3,
> >> + aml_store(
> >> + aml_name("PPRQ"),
> >> + aml_index(aml_name("TPM2"), aml_int(1))));
> >> + aml_append(ifctx3, aml_return(aml_name("TPM2")));
> >> + }
> >> + aml_append(ifctx2, ifctx3);
> >> +
> >> + /*
> >> + * A return value of {0, 23, 1} indicates that
> >> + * operation 23 with argument 1 is pending.
> >> + */
> >> + rev = aml_local(1);
> >> + ifctx3 = aml_if(aml_equal(rev, aml_int(2)));
> >> + {
> >> + /* TPM3[1] = PPRQ */
> >> + aml_append(ifctx3,
> >> + aml_store(
> >> + aml_name("PPRQ"),
> >> + aml_index(aml_name("TPM3"), aml_int(1))));
> >> + /* TPM3[2] = PPRM */
> >> + aml_append(ifctx3,
> >> + aml_store(
> >> + aml_name("PPRM"),
> >> + aml_index(aml_name("TPM3"), aml_int(2))));
> >> + aml_append(ifctx3, aml_return(aml_name("TPM3")));
> >> + }
> >> + aml_append(ifctx2, ifctx3);
> >> + }
> >> + aml_append(ifctx, ifctx2);
> >> +
> >> + /*
> >> + * 8.1.4 Get Platform-Specific Action to Transition to
> >> + * Pre-OS Environment
> >> + *
> >> + * Arg 2 (Integer): Function Index = 4
> >> + * Arg 3 (Package): Arguments = Empty Package
> >> + * Returns: Type: Integer
> >> + * 0: None
> >> + * 1: Shutdown
> >> + * 2: Reboot
> >> + * 3: OS Vendor-specific
> >> + */
> >> + func_idx = aml_local(0);
> >> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(4)));
> >> + {
> >> + /* reboot */
> >> + aml_append(ifctx2, aml_return(aml_int(2)));
> >> + }
> >> + aml_append(ifctx, ifctx2);
> >> +
> >> + /*
> >> + * 8.1.5 Return TPM Operation Response to OS Environment
> >> + *
> >> + * Arg 2 (Integer): Function Index = 5
> >> + * Arg 3 (Package): Arguments = Empty Package
> >> + * Returns: Type: Package of Integer
> >> + * Integer 1: Function Return code
> >> + * 0: Success
> >> + * 1: General Failure
> >> + * Integer 2: Most recent operation request
> >> + * 0: None
> >> + * >0: Operation Value of the most recent request
> >> + * Integer 3: Response to the most recent operation request
> >> + * 0: Success
> >> + * 0x00000001..0x00000FFF: Corresponding TPM
> >> + * error code
> >> + * 0xFFFFFFF0: User Abort or timeout of dialog
> >> + * 0xFFFFFFF1: firmware Failure
> >> + */
> >> + func_idx = aml_local(0);
> >> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(5)));
> >> + {
> >> + /* TPM3[1] = LPPR */
> >> + aml_append(ifctx2,
> >> + aml_store(
> >> + aml_name("LPPR"),
> >> + aml_index(aml_name("TPM3"), aml_int(1))));
> >> + /* TPM3[2] = PPRP */
> >> + aml_append(ifctx2,
> >> + aml_store(
> >> + aml_name("PPRP"),
> >> + aml_index(aml_name("TPM3"), aml_int(2))));
> >> + aml_append(ifctx2, aml_return(aml_name("TPM3")));
> >> + }
> >> + aml_append(ifctx, ifctx2);
> >> +
> >> + /*
> >> + * 8.1.6 Submit preferred user language
> >> + *
> >> + * Arg 2 (Integer): Function Index = 6
> >> + * Arg 3 (Package): Arguments = String Package
> >> + * Preferred language code
> >> + * Returns: Type: Integer
> >> + * Function Return Code
> >> + * 3: Not implemented
> >> + */
> >> + func_idx = aml_local(0);
> >> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(6)));
> >> + {
> >> + /* 3 = not implemented */
> >> + aml_append(ifctx2, aml_return(aml_int(3)));
> >> + }
> >> + aml_append(ifctx, ifctx2);
> >> +
> >> + /*
> >> + * 8.1.7 Submit TPM Operation Request to Pre-OS Environment 2
> >> + *
> >> + * Arg 2 (Integer): Function Index = 7
> >> + * Arg 3 (Package): Arguments = Package: Type: Integer
> >> + * Integer 1: Operation Value of the Request
> >> + * Integer 2: Argument for Operation (optional)
> >> + * Returns: Type: Integer
> >> + * 0: Success
> >> + * 1: Not Implemented
> >> + * 2: General Failure
> >> + * 3: Operation blocked by current firmware settings
> >> + */
> >> + func_idx = aml_local(0);
> >> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(7)));
> >> + {
> >> + /* get opcode */
> >> + op = aml_derefof(aml_index(aml_arg(3), aml_int(0)));
> >> + aml_append(ifctx2, aml_store(op, aml_local(0)));
> >> +
> >> + /* get opcode flags */
> >> + op = aml_local(0);
> >> + aml_append(ifctx2, aml_store(aml_call1("TPFN", op),
> >> + aml_local(1)));
> >> + /* if func[opcode] & TPM_PPI_FUNC_NOT_IMPLEMENTED */
> >> + op_flags = aml_local(1);
> >> + ifctx3 = aml_if(
> >> + aml_equal(
> >> + aml_and(op_flags, aml_int(TPM_PPI_FUNC_MASK), NULL),
> >> + aml_int(TPM_PPI_FUNC_NOT_IMPLEMENTED)));
> >> + {
> >> + /* 1: not implemented */
> >> + aml_append(ifctx3, aml_return(aml_int(1)));
> >> + }
> >> + aml_append(ifctx2, ifctx3);
> >> +
> >> + /* if func[opcode] & TPM_PPI_FUNC_BLOCKED */
> >> + op_flags = aml_local(1);
> >> + ifctx3 = aml_if(
> >> + aml_equal(
> >> + aml_and(op_flags, aml_int(TPM_PPI_FUNC_MASK), NULL),
> >> + aml_int(TPM_PPI_FUNC_BLOCKED)));
> >> + {
> >> + /* 3: blocked by firmware */
> >> + aml_append(ifctx3, aml_return(aml_int(3)));
> >> + }
> >> + aml_append(ifctx2, ifctx3);
> >> +
> >> + /* revision to integer */
> >> + aml_append(ifctx2,
> >> + aml_store(
> >> + aml_to_integer(aml_arg(1)),
> >> + aml_local(1)));
> >> +
> >> + rev = aml_local(1);
> >> + ifctx3 = aml_if(aml_equal(rev, aml_int(1)));
> >> + {
> >> + /* revision 1 */
> >> + /* PPRQ = op */
> >> + op = aml_local(0);
> >> + aml_append(ifctx3, aml_store(op, aml_name("PPRQ")));
> >> + /* no argument, PPRM = 0 */
> >> + aml_append(ifctx3, aml_store(aml_int(0),
> >> + aml_name("PPRM")));
> >> + }
> >> + aml_append(ifctx2, ifctx3);
> >> +
> >> + rev = aml_local(1);
> >> + ifctx3 = aml_if(aml_equal(rev, aml_int(2)));
> >> + {
> >> + /* revision 2 */
> >> + /* PPRQ = op */
> >> + op = aml_local(0);
> >> + op_arg = aml_derefof(aml_index(aml_arg(3), aml_int(1)));
> >> + aml_append(ifctx3, aml_store(op, aml_name("PPRQ")));
> >> + /* PPRM = arg3[1] */
> >> + aml_append(ifctx3, aml_store(op_arg, aml_name("PPRM")));
> >> + }
> >> + aml_append(ifctx2, ifctx3);
> >> + /* 0: success */
> >> + aml_append(ifctx2, aml_return(aml_int(0)));
> >> + }
> >> + aml_append(ifctx, ifctx2);
> >> +
> >> + /*
> >> + * 8.1.8 Get User Confirmation Status for Operation
> >> + *
> >> + * Arg 2 (Integer): Function Index = 8
> >> + * Arg 3 (Package): Arguments = Package: Type: Integer
> >> + * Operation Value that may need user confirmation
> >> + * Returns: Type: Integer
> >> + * 0: Not implemented
> >> + * 1: Firmware only
> >> + * 2: Blocked for OS by firmware configuration
> >> + * 3: Allowed and physically present user required
> >> + * 4: Allowed and physically present user not required
> >> + */
> >> + func_idx = aml_local(0);
> >> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(8)));
> >> + {
> >> + /* get opcode */
> >> + op = aml_derefof(aml_index(aml_arg(3), aml_int(0)));
> >> + aml_append(ifctx2, aml_store(op, aml_local(0)));
> >> +
> >> + /* get opcode flags */
> >> + op = aml_local(0);
> >> + aml_append(ifctx2, aml_store(aml_call1("TPFN", op),
> >> + aml_local(1)));
> >> + op_flags = aml_local(1);
> >> + /* return confirmation status code */
> >> + aml_append(ifctx2,
> >> + aml_return(
> >> + aml_and(op_flags,
> >> + aml_int(TPM_PPI_FUNC_MASK), NULL)));
> >> + }
> >> + aml_append(ifctx, ifctx2);
> >> +
> >> + aml_append(ifctx, aml_return(aml_buffer(1, zerobyte)));
> >> + }
> >> + aml_append(method, ifctx);
> >> + }
> >> + aml_append(dev, method);
> >> +}
> >> +
> >> static void
> >> build_dsdt(GArray *table_data, BIOSLinker *linker,
> >> AcpiPmInfo *pm, AcpiMiscInfo *misc,
> >> @@ -2153,6 +2569,9 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
> >> */
> >> /* aml_append(crs, aml_irq_no_flags(TPM_TIS_IRQ)); */
> >> aml_append(dev, aml_name_decl("_CRS", crs));
> >> +
> >> + build_tpm_ppi(dev);
> >> +
> >> aml_append(scope, dev);
> >> }
> >>
> >> @@ -2172,6 +2591,8 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
> >> aml_append(method, aml_return(aml_int(0x0f)));
> >> aml_append(dev, method);
> >>
> >> + build_tpm_ppi(dev);
> >> +
> >> aml_append(sb_scope, dev);
> >> }
> >>
> >> @@ -2920,7 +3341,7 @@ void acpi_setup(void)
> >> tpm_config = (FWCfgTPMConfig) {
> >> .tpmppi_address = cpu_to_le32(TPM_PPI_ADDR_BASE),
> >> .tpm_version = cpu_to_le32(tpm_get_version(tpm_find())),
> >> - .tpmppi_version = cpu_to_le32(TPM_PPI_VERSION_NONE)
> >> + .tpmppi_version = cpu_to_le32(TPM_PPI_VERSION_1_30)
> > s/cpu_to_le32//
>
> ok
>
> >
> >> };
> >> fw_cfg_add_file(pcms->fw_cfg, "etc/tpm/config",
> >> &tpm_config, sizeof tpm_config);
> >> diff --git a/docs/specs/tpm.txt b/docs/specs/tpm.txt
> >> index 2ddb768084..c27762c723 100644
> >> --- a/docs/specs/tpm.txt
> >> +++ b/docs/specs/tpm.txt
> >> @@ -62,6 +62,85 @@ URL:
> >>
> >> https://trustedcomputinggroup.org/tcg-acpi-specification/
> >>
> >> +== ACPI PPI Interface ==
> >> +
> >> +QEMU supports the Physical Presence Interface (PPI) for TPM 1.2 and TPM 2. This
> >> +interface requires ACPI and firmware support. The specification can be found at
> >> +the following URL:
> >> +
> >> +https://trustedcomputinggroup.org/resource/tcg-physical-presence-interface-specification/
> >> +
> >> +PPI enables a system administrator (root) to request a modification to the
> >> +TPM upon reboot. The PPI specification defines the operation requests and the
> >> +actions the firmware has to take. The system administrator passes the operation
> >> +request number to the firmware through an ACPI interface which writes this
> >> +number to a memory location that the firmware knows. Upon reboot, the firmware
> >> +finds the number and sends commands to the the TPM. The firmware writes the TPM
> >> +result code and the operation request number to a memory location that ACPI can
> >> +read from and pass the result on to the administrator.
> >> +
> >> +The PPI specification defines a set of mandatory and optional operations for
> >> +the firmware to implement. The ACPI interface also allows an administrator to
> >> +list the supported operations. In QEMU the ACPI code is generated by QEMU, yet
> >> +the firmware needs to implement support on a per-operations basis, and
> >> +different firmwares may support a different subset. Therefore, QEMU introduces
> >> +the virtual memory device for PPI where the firmware can indicate which
> >> +operations it supports and ACPI can enable the ones that are supported and
> >> +disable all others. This interface lies in main memory and has the following
> >> +layout:
> >> +
> >> + +----------+--------+--------+-------------------------------------------+
> >> + | Field | Length | Offset | Description |
> >> + +----------+--------+--------+-------------------------------------------+
> >> + | func | 0x100 | 0x000 | Firmware sets values for each supported |
> >> + | | | | operation. See defined values below. |
> >> + +----------+--------+--------+-------------------------------------------+
> >> + | ppin | 0x1 | 0x100 | SMI interrupt to use. Set by firmware. |
> >> + | | | | Not supported. |
> >> + +----------+--------+--------+-------------------------------------------+
> >> + | ppip | 0x4 | 0x101 | ACPI function index to pass to SMM code. |
> >> + | | | | Set by ACPI. Not supported. |
> >> + +----------+--------+--------+-------------------------------------------+
> >> + | pprp | 0x4 | 0x105 | Result of last executed operation. Set by |
> >> + | | | | firmware. See function index 5 for values.|
> >> + +----------+--------+--------+-------------------------------------------+
> >> + | pprq | 0x4 | 0x109 | Operation request number to execute. See |
> >> + | | | | 'Physical Presence Interface Operation |
> >> + | | | | Summary' tables in specs. Set by ACPI. |
> >> + +----------+--------+--------+-------------------------------------------+
> >> + | pprm | 0x4 | 0x10d | Operation request optional parameter. |
> >> + | | | | Values depend on operation. Set by ACPI. |
> >> + +----------+--------+--------+-------------------------------------------+
> >> + | lppr | 0x4 | 0x111 | Last executed operation request number. |
> >> + | | | | Copied from pprq field by firmware. |
> >> + +----------+--------+--------+-------------------------------------------+
> >> + | fret | 0x4 | 0x115 | Result code from SMM function. |
> >> + | | | | Not supported. |
> >> + +----------+--------+--------+-------------------------------------------+
> >> + | res1 | 0x40 | 0x119 | Reserved for future use |
> >> + +----------+--------+--------+-------------------------------------------+
> >> + | next_step| 0x1 | 0x159 | Operation to execute after reboot by |
> >> + | | | | firmware. Used by firmware. |
> >> + +----------+--------+--------+-------------------------------------------+
> >> +
> >> + The following values are supported for the 'func' field. They correspond
> >> + to the values used by ACPI function index 8.
> >> +
> >> + +----------+-------------------------------------------------------------+
> >> + | value | Description |
> >> + +----------+-------------------------------------------------------------+
> >> + | 0 | Operation is not implemented. |
> >> + +----------+-------------------------------------------------------------+
> >> + | 1 | Operation is only accessible through firmware. |
> >> + +----------+-------------------------------------------------------------+
> >> + | 2 | Operation is blocked for OS by firmware configuration. |
> >> + +----------+-------------------------------------------------------------+
> >> + | 3 | Operation is allowed and physically present user required. |
> >> + +----------+-------------------------------------------------------------+
> >> + | 4 | Operation is allowed and physically present user is not |
> >> + | | required. |
> >> + +----------+-------------------------------------------------------------+
> >> +
> >>
> >> QEMU files related to TPM ACPI tables:
> >> - hw/i386/acpi-build.c
> >
> >
>
>
>
Hi
On Fri, Jun 29, 2018 at 4:09 PM, Igor Mammedov <imammedo@redhat.com> wrote:
> On Thu, 28 Jun 2018 17:24:47 +0200
> Marc-André Lureau <marcandre.lureau@gmail.com> wrote:
>
>> Hi
>>
>> On Wed, Jun 27, 2018 at 3:19 PM, Igor Mammedov <imammedo@redhat.com> wrote:
>> > On Tue, 26 Jun 2018 14:23:43 +0200
>> > Marc-André Lureau <marcandre.lureau@redhat.com> wrote:
>> >
>> >> From: Stefan Berger <stefanb@linux.vnet.ibm.com>
>> >>
>> >> The TPM Physical Presence interface consists of an ACPI part, a shared
>> >> memory part, and code in the firmware. Users can send messages to the
>> >> firmware by writing a code into the shared memory through invoking the
>> >> ACPI code. When a reboot happens, the firmware looks for the code and
>> >> acts on it by sending sequences of commands to the TPM.
>> >>
>> >> This patch adds the ACPI code. It is similar to the one in EDK2 but doesn't
>> >> assume that SMIs are necessary to use. It uses a similar datastructure for
>> >> the shared memory as EDK2 does so that EDK2 and SeaBIOS could both make use
>> >> of it. I extended the shared memory data structure with an array of 256
>> >> bytes, one for each code that could be implemented. The array contains
>> >> flags describing the individual codes. This decouples the ACPI implementation
>> >> from the firmware implementation.
>> >>
>> >> The underlying TCG specification is accessible from the following page.
>> >>
>> >> https://trustedcomputinggroup.org/tcg-physical-presence-interface-specification/
>> >>
>> >> This patch implements version 1.30.
>> >
>> > I've made several suggestions below how to improve aml part of patch a bit,
>> > will review v6 once it's done
>> > /hopefully it would be more readable, considering that ASM language is horrible to begin with/
>> >
>> >>
>> >> Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
>> >>
>> >> ---
>> >>
>> >> v6:
>> >> - more code documentation (Marc-André)
>> >> - use some explicit named variables to ease reading (Marc-André)
>> >> - use fixed size fields/memory regions, remove PPI struct (Marc-André)
>> >> - only add PPI ACPI methods if PPI is enabled (Marc-André)
>> >> - document the qemu/firmware ACPI memory region (Stefan)
>> >>
>> >> v5 (Marc-André):
>> >> - /struct tpm_ppi/struct TPMPPIData
>> >>
>> >> v4 (Marc-André):
>> >> - replace 'DerefOf (FUNC [N])' with a function, to fix Windows ACPI
>> >> handling.
>> >> - replace 'return Package (..) {} ' with scoped variables, to fix
>> >> Windows ACPI handling.
>> >>
>> >> v3:
>> >> - add support for PPI to CRB
>> >> - split up OperationRegion TPPI into two parts, one containing
>> >> the registers (TPP1) and the other one the flags (TPP2); switched
>> >> the order of the flags versus registers in the code
>> >> - adapted ACPI code to small changes to the array of flags where
>> >> previous flag 0 was removed and now shifting right wasn't always
>> >> necessary anymore
>> >>
>> >> v2:
>> >> - get rid of FAIL variable; function 5 was using it and always
>> >> returns 0; the value is related to the ACPI function call not
>> >> a possible failure of the TPM function call.
>> >> - extend shared memory data structure with per-opcode entries
>> >> holding flags and use those flags to determine what to return
>> >> to caller
>> >> - implement interface version 1.3
>> >> ---
>> >> include/hw/acpi/tpm.h | 8 +
>> >> hw/i386/acpi-build.c | 423 +++++++++++++++++++++++++++++++++++++++++-
>> >> docs/specs/tpm.txt | 79 ++++++++
>> >> 3 files changed, 509 insertions(+), 1 deletion(-)
>> >>
>> >> diff --git a/include/hw/acpi/tpm.h b/include/hw/acpi/tpm.h
>> >> index f79d68a77a..e0bd07862e 100644
>> >> --- a/include/hw/acpi/tpm.h
>> >> +++ b/include/hw/acpi/tpm.h
>> >> @@ -196,4 +196,12 @@ REG32(CRB_DATA_BUFFER, 0x80)
>> >> #define TPM_PPI_VERSION_NONE 0
>> >> #define TPM_PPI_VERSION_1_30 1
>> >>
>> >> +/* whether function is blocked by BIOS settings; bits 0, 1, 2 */
>> >> +#define TPM_PPI_FUNC_NOT_IMPLEMENTED (0 << 0)
>> >> +#define TPM_PPI_FUNC_BIOS_ONLY (1 << 0)
>> >> +#define TPM_PPI_FUNC_BLOCKED (2 << 0)
>> >> +#define TPM_PPI_FUNC_ALLOWED_USR_REQ (3 << 0)
>> >> +#define TPM_PPI_FUNC_ALLOWED_USR_NOT_REQ (4 << 0)
>> >> +#define TPM_PPI_FUNC_MASK (7 << 0)
>> >> +
>> >> #endif /* HW_ACPI_TPM_H */
>> >> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
>> >> index d9320845ed..d815af4eef 100644
>> >> --- a/hw/i386/acpi-build.c
>> >> +++ b/hw/i386/acpi-build.c
>> >> @@ -43,6 +43,7 @@
>> >> #include "hw/acpi/memory_hotplug.h"
>> >> #include "sysemu/tpm.h"
>> >> #include "hw/acpi/tpm.h"
>> >> +#include "hw/tpm/tpm_ppi.h"
>> >> #include "hw/acpi/vmgenid.h"
>> >> #include "sysemu/tpm_backend.h"
>> >> #include "hw/timer/mc146818rtc_regs.h"
>> >> @@ -1789,6 +1790,421 @@ static Aml *build_q35_osc_method(void)
>> >> return method;
>> >> }
>> >>
>> >> +static void
>> >> +build_tpm_ppi(Aml *dev)
>> >> +{
>> >> + Aml *method, *name, *field, *ifctx, *ifctx2, *ifctx3, *pak;
>> >> + int i;
>> >> +
>> >> + if (!object_property_get_bool(OBJECT(tpm_find()), "ppi", &error_abort)) {
>> > if tpm_find() == NULL -> BAAM???
>> >
>> > I'd do it like this:
>> > tmp = tpm_find()
>> > if (TPM_IS_TIS(tpm) {
>> > ...
>> > if (object_property_get_bool(tpm), "ppi", &error_abort)) {
>> > build_tpm_ppi(tpm, dev)
>> > }
>> > ...
>> > }
>> >
>> > if (TPM_IS_CRB(tpm))
>> > {
>> > ....
>> > }
>> >
>> > a bit more verbose but then the reader won't have to jump inside of
>> > build_tpm_ppi() if he/she is not interested in it.
>>
>> ok, I pass the tpm to build_tpm_ppi() for the ppi property check, and
>> avoid extra lookup.
>>
>> >
>> >> + return;
>> >> + }
>> >> + /*
>> >> + * TPP1 is for the flags that indicate which PPI operations
>> >> + * are supported by the firmware. The firmware is expected to
>> >> + * write these flags.
>> >> + */
>> >> + aml_append(dev,
>> >> + aml_operation_region("TPP1", AML_SYSTEM_MEMORY,
>> >> + aml_int(TPM_PPI_ADDR_BASE), 0x100));
>> >> + field = aml_field("TPP1", AML_ANY_ACC, AML_NOLOCK, AML_PRESERVE);
>> >> + for (i = 0; i < 0x100; i++) {
>> >> + char *tmp = g_strdup_printf("FN%02X", i);
>> >> + aml_append(field, aml_named_field(tmp, 8));
>> >> + g_free(tmp);
>> >> + }
>> >> + aml_append(dev, field);
>> >> +
>> >> + /*
>> >> + * TPP2 is for the registers that ACPI code used to pass
>> >> + * the PPI code and parameter (PPRQ, PPRM) to the firmware.
>> >> + */
>> >> + aml_append(dev,
>> >> + aml_operation_region("TPP2", AML_SYSTEM_MEMORY,
>> >> + aml_int(TPM_PPI_ADDR_BASE + 0x100),
>> >> + 0x5A));
>> >> + field = aml_field("TPP2", AML_ANY_ACC, AML_NOLOCK, AML_PRESERVE);
>> >> + aml_append(field, aml_named_field("PPIN", 8));
>> >> + aml_append(field, aml_named_field("PPIP", 32));
>> >> + aml_append(field, aml_named_field("PPRP", 32));
>> >> + aml_append(field, aml_named_field("PPRQ", 32));
>> >> + aml_append(field, aml_named_field("PPRM", 32));
>> >> + aml_append(field, aml_named_field("LPPR", 32));
>> >> + aml_append(dev, field);
>> >> +
>> >> + /*
>> >> + * A function to return the value of DerefOf (FUNC [N]), by using
>> >> + * accessing the fields individually instead. This is a workaround
>> >> + * for what looks like a Windows ACPI bug in all versions so far
>> >> + * (fwiw, DerefOf (FUNC [N]) works on Linux).
>> >> + */
>> >> + method = aml_method("TPFN", 1, AML_SERIALIZED);
>> >> + {
>> >> + for (i = 0; i < 0x100; i++) {
>> >> + ifctx = aml_if(aml_equal(aml_int(i), aml_arg(0)));
>> >> + {
>> >> + aml_append(ifctx, aml_return(aml_name("FN%02X", i)));
>> >> + }
>> >> + aml_append(method, ifctx);
>> >> + }
>> >> + aml_append(method, aml_return(aml_int(0)));
>> >> + }
>> >> + aml_append(dev, method);
>> >> +
>> >> + pak = aml_package(2);
>> >> + aml_append(pak, aml_int(0));
>> >> + aml_append(pak, aml_int(0));
>> >> + name = aml_name_decl("TPM2", pak);
>> >> + aml_append(dev, name);
>> >> +
>> >> + pak = aml_package(3);
>> >> + aml_append(pak, aml_int(0));
>> >> + aml_append(pak, aml_int(0));
>> >> + aml_append(pak, aml_int(0));
>> >> + name = aml_name_decl("TPM3", pak);
>> > Aml one = aml_int(1)
>> > Aml tpm3 = local(x)
>> > aml_store(pak, tpm3)
>> >
>> > ... and then later ...
>> >
>> > {
>> > /* TPM2[1] = PPRQ */
>> > aml_append(ifctx3, aml_store(aml_name("PPRQ"), aml_index(tpm2, one)));
>> > aml_append(ifctx3, aml_return(tpm2));
>> >
>> > which would make code a bit more readable
>> >
>>
>> But you would have to create aml_int(), aml_local() for every usage. I
>> don't think we gain in readability.
> Aml* variables can be reused as aml_append/aml_foo copies input arguments.
> Take look at build_cpus_aml() how it makes code more readable.
>
>> >> + aml_append(dev, name);
>> > both packages could be local vars as return is done by value
>> >
>> >> +
>> >> + method = aml_method("_DSM", 4, AML_SERIALIZED);
>> >> + {
>> >> + uint8_t zerobyte[1] = { 0 };
>> >> + Aml *func_idx, *rev, *op, *op_arg, *op_flags;
>> >> +
>> >> + ifctx = aml_if(
>> >> + aml_equal(aml_arg(0),
>> >> + aml_touuid("3DDDFAA6-361B-4EB4-A424-8D10089D1653")));
>> > aml_equal(uuid, aml_touuid("3DDDFAA6-361B-4EB4-A424-8D10089D1653"))
>>
>> Ok
>>
>> >
>> >> + {
>> >> + func_idx = aml_local(0);
>> >> + aml_append(ifctx,
>> >> + aml_store(aml_to_integer(aml_arg(2)), func_idx));
>> > why do you need aml_to_integer() cast here?
>> >
>> > Wouldn't following just work:
>> >
>> > Aml function = aml_arg(2)
>> >
>> > I'd suggest to use "function" for consistency with nvdimm _DSM
>>
>> ok
>>
>> >
>> > you can use the same naming approach for other arguments i.e.
>> > arguments = aml_arg(3)
>> >
>>
>> ok
>>
>> >> +
>> >> + /* standard DSM query function */
>> >> + func_idx = aml_local(0);
>> > I don't think you need to init it twice.
>> >
>>
>> That looks right, and it's the way nvdimm ACPI code is written, but is
>> not following the usual convention to give up the ownership when given
>> as argument to other AML building function.
>
> That's misunderstanding of how it works, there isn't such convention
> input argument is copied into output AML element.
>
>
>> Sad we don't stick to a single usage pattern (giving up ownership).
>> Some day, someone will look at fixing the leaks, and that may make its
>> work easier if the code was consistent...
> Aml* pointers aren't leaked, see aml_alloc() which stores all allocations
> into a list which is freed later by free_aml_allocator() when table
> is build.
>
oh ok, GC magic :)
>
>> But I'll follow your advise for now.
>>
>> >> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(0)));
>> >> + {
>> >> + uint8_t byte_list[2] = { 0xff, 0x01 };
>> >> + aml_append(ifctx2, aml_return(aml_buffer(2, byte_list)));
>> >> + }
>> >> + aml_append(ifctx, ifctx2);
>> >> +
>> >> + /*
>> >> + * 8.1.1 Get Physical Presence Interface Version
>> > like Michael noted use version/chapter pair to as reference
>> >
>> > ex: /* ACPI 1.0b: 16.2.5.2 Named Objects Encoding: DefOpRegion */
>>
>> ok
>>
>> >
>> >> + *
>> >> + * Arg 2 (Integer): Function Index = 1
>> >> + * Arg 3 (Package): Arguments = Empty Package
>> >> + * Returns: Type: String
>> >> + */
>> >> + func_idx = aml_local(0);
>> > not needed
>> >
>> >> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(1)));
>> >> + {
>> >> + aml_append(ifctx2, aml_return(aml_string("1.3")));
>> >> + }
>> >> + aml_append(ifctx, ifctx2);
>> >> +
>> >> + /*
>> >> + * 8.1.2 Submit TPM Operation Request to Pre-OS Environment
>> >> + *
>> >> + * Arg 2 (Integer): Function Index = 2
>> >> + * Arg 3 (Package): Arguments = Package: Type: Integer
>> >> + * Operation Value of the Request
>> >> + * Returns: Type: Integer
>> >> + * 0: Success
>> >> + * 1: Operation Value of the Request Not Supported
>> >> + * 2: General Failure
>> >> + */
>> >> + func_idx = aml_local(0);
>> > ditto and the same in other places
>> >
>> >> + ifctx2 = aml_if(aml_equal(func_idx, aml_int(2)));
>> >> + {
>> >> + /* get opcode */
>> >> + op = aml_derefof(aml_index(aml_arg(3), aml_int(0)));
>> >> + aml_append(ifctx2, aml_store(op, aml_local(0)));
>> > ^^^ what this local(0) is? suggest to use named var here (in C sense)
>> >> +
>> >> + /* get opcode flags */
>> >> + op = aml_local(0);
>> > use other local to make ASL less confusion (i.e. try not to reuse local vars for something else)
>>
>> I must say I get a bit confused by the code style change you request.
>> The original code from Stefan was more straightforward to me. Now it
>> seems C variables adds another layer of complexity. I think it's
>> easier if you come up with a follow-up patch for further cleanup
>> iterations, as I find it hard to match your wanted style.
>
> Whole point of review is to merge code that doesn't need to be
> rewritten later on and to show preferred style for ACPI code
> so I wouldn't be the only one who knows how it is supposed to work.
>
> Now about my original comment.
> What we have in this patch:
> func_idx = aml_local(0);
> ...
> op = aml_local(0);
> so resulting AML decompiled in to ASL would (re)use Local0 with different meanings
> what I've suggested is:
> Aml *func_idx = aml_local(0);
> Aml *op = aml_local(1);
> Aml *foo = aml_local(X);
>
> where ASL would retain LocalX meaning throughout method, making it a bit readable.
>
Ok, hopefully last iteration is closer to that goal.
>
>> >> + aml_append(ifctx2,
>> >> + aml_store(aml_call1("TPFN", op), aml_local(1)));
>> > ^^^ what this local(1) is?
>> >
>> >> +
>> >> + op_flags = aml_local(1);
>> > I'd init all named vars at the top of function where it's easy to see what is what
>> > and use them later. ex: nvdimm_build_common_dsm()
>>
>> But the arguments depend on the function.
> some maybe, but
> function index is common, arguments also, so one could do following:
>
> Aml *func = aml_arg(2);
> Aml *args = aml_arg(3);
>
> without storing them in locals, and then use them within the method as necessary
I did that for aml_arg(0..2). just now reading ACPI DSM spec, I
realize aml_arg(3) is always supposed to be optional arguments
package. So I agree, and my last iteration can be further improved in
that direction.
thanks
--
Marc-André Lureau
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