[Qemu-devel] [PATCH v6 4/4] acpi: build TPM Physical Presence interface

Marc-André Lureau posted 4 patches 7 years, 5 months ago
There is a newer version of this series
[Qemu-devel] [PATCH v6 4/4] acpi: build TPM Physical Presence interface
Posted by Marc-André Lureau 7 years, 5 months ago
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>
[ Marc-André - ACPI code improvements and windows fixes ]
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>

---

v7: (Marc-André)
 - use first spec version/section in code comments
 - use more variables for ASL code building
 - remove unnecessering ToInteger() calls

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  | 403 +++++++++++++++++++++++++++++++++++++++++-
 docs/specs/tpm.txt    |  79 +++++++++
 3 files changed, 487 insertions(+), 3 deletions(-)

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 ebd64c4818..263677f3e4 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 +1790,396 @@ static Aml *build_q35_osc_method(void)
     return method;
 }
 
+static void
+build_tpm_ppi(TPMIf *tpm, Aml *dev)
+{
+    Aml *method, *field, *ifctx, *ifctx2, *ifctx3;
+    Aml *pak, *tpm2, *tpm3, *pprm, *pprq;
+    int i;
+
+    if (!object_property_get_bool(OBJECT(tpm), "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);
+    pprq = aml_name("PPRQ");
+    pprm = aml_name("PPRM");
+
+    /*
+     * 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));
+    aml_append(dev, aml_name_decl("TPM2", pak));
+    tpm2 = aml_name("TPM2");
+
+    pak = aml_package(3);
+    aml_append(pak, aml_int(0));
+    aml_append(pak, aml_int(0));
+    aml_append(pak, aml_int(0));
+    aml_append(dev, aml_name_decl("TPM3", pak));
+    tpm3 = aml_name("TPM3");
+
+    method = aml_method("_DSM", 4, AML_SERIALIZED);
+    {
+        uint8_t zerobyte[1] = { 0 };
+        Aml *function, *arguments, *rev, *op, *op_arg, *op_flags, *uuid;
+
+        uuid = aml_arg(0);
+        rev = aml_arg(1);
+        function = aml_arg(2);
+        ifctx = aml_if(
+            aml_equal(uuid,
+                      aml_touuid("3DDDFAA6-361B-4EB4-A424-8D10089D1653")));
+        {
+            /* standard DSM query function */
+            ifctx2 = aml_if(aml_equal(function, aml_int(0)));
+            {
+                uint8_t byte_list[2] = { 0xff, 0x01 };
+                aml_append(ifctx2, aml_return(aml_buffer(2, byte_list)));
+            }
+            aml_append(ifctx, ifctx2);
+
+            /*
+             * PPI 1.0: 2.1.1 Get Physical Presence Interface Version
+             *
+             * Arg 2 (Integer): Function Index = 1
+             * Arg 3 (Package): Arguments = Empty Package
+             * Returns: Type: String
+             */
+            ifctx2 = aml_if(aml_equal(function, aml_int(1)));
+            {
+                aml_append(ifctx2, aml_return(aml_string("1.3")));
+            }
+            aml_append(ifctx, ifctx2);
+
+            /*
+             * PPI 1.0: 2.1.3 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
+             */
+            ifctx2 = aml_if(aml_equal(function, aml_int(2)));
+            {
+                /* get opcode */
+                arguments = aml_arg(3);
+                op = aml_local(0);
+                op_flags = aml_local(1);
+                aml_append(ifctx2,
+                           aml_store(aml_derefof(aml_index(arguments,
+                                                           aml_int(0))), op));
+
+                /* get opcode flags */
+                aml_append(ifctx2,
+                           aml_store(aml_call1("TPFN", op), op_flags));
+
+                /* 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: Operation Value of the Request Not Supported */
+                    aml_append(ifctx3, aml_return(aml_int(1)));
+                }
+                aml_append(ifctx2, ifctx3);
+
+                aml_append(ifctx2, aml_store(op, pprq));
+                aml_append(ifctx2, aml_store(aml_int(0), pprm));
+                /* 0: success */
+                aml_append(ifctx2, aml_return(aml_int(0)));
+            }
+            aml_append(ifctx, ifctx2);
+
+            /*
+             * PPI 1.0: 2.1.4 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
+             */
+            ifctx2 = aml_if(aml_equal(function, aml_int(3)));
+            {
+                /*
+                 * Revision ID of 1, no integer parameter beyond
+                 * parameter two are expected
+                 */
+                ifctx3 = aml_if(aml_equal(rev, aml_int(1)));
+                {
+                    /* TPM2[1] = PPRQ */
+                    aml_append(ifctx3,
+                               aml_store(pprq, aml_index(tpm2, aml_int(1))));
+                    aml_append(ifctx3, aml_return(tpm2));
+                }
+                aml_append(ifctx2, ifctx3);
+
+                /*
+                 * A return value of {0, 23, 1} indicates that
+                 * operation 23 with argument 1 is pending.
+                 */
+                ifctx3 = aml_if(aml_equal(rev, aml_int(2)));
+                {
+                    /* TPM3[1] = PPRQ */
+                    aml_append(ifctx3,
+                               aml_store(pprq, aml_index(tpm3, aml_int(1))));
+                    /* TPM3[2] = PPRM */
+                    aml_append(ifctx3,
+                               aml_store(pprm, aml_index(tpm3, aml_int(2))));
+                    aml_append(ifctx3, aml_return(tpm3));
+                }
+                aml_append(ifctx2, ifctx3);
+            }
+            aml_append(ifctx, ifctx2);
+
+            /*
+             * PPI 1.0: 2.1.5 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
+             */
+            ifctx2 = aml_if(aml_equal(function, aml_int(4)));
+            {
+                /* reboot */
+                aml_append(ifctx2, aml_return(aml_int(2)));
+            }
+            aml_append(ifctx, ifctx2);
+
+            /*
+             * PPI 1.0: 2.1.6 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
+             */
+            ifctx2 = aml_if(aml_equal(function, aml_int(5)));
+            {
+                /* TPM3[1] = LPPR */
+                aml_append(ifctx2,
+                           aml_store(aml_name("LPPR"),
+                                     aml_index(tpm3, aml_int(1))));
+                /* TPM3[2] = PPRP */
+                aml_append(ifctx2,
+                           aml_store(aml_name("PPRP"),
+                                     aml_index(tpm3, aml_int(2))));
+                aml_append(ifctx2, aml_return(tpm3));
+            }
+            aml_append(ifctx, ifctx2);
+
+            /*
+             * PPI 1.0: 2.1.7 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
+             */
+            ifctx2 = aml_if(aml_equal(function, aml_int(6)));
+            {
+                /* 3 = not implemented */
+                aml_append(ifctx2, aml_return(aml_int(3)));
+            }
+            aml_append(ifctx, ifctx2);
+
+            /*
+             * PPI 1.1: 2.1.7 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
+             */
+            ifctx2 = aml_if(aml_equal(function, aml_int(7)));
+            {
+                /* get opcode */
+                arguments = aml_arg(3);
+                op = aml_local(0);
+                op_flags = aml_local(1);
+                aml_append(ifctx2, aml_store(aml_derefof(aml_index(arguments,
+                                                                   aml_int(0))),
+                                             op));
+
+                /* get opcode flags */
+                aml_append(ifctx2, aml_store(aml_call1("TPFN", op),
+                                             op_flags));
+                /* 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);
+
+                /* if func[opcode] & TPM_PPI_FUNC_BLOCKED */
+                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 */
+                ifctx3 = aml_if(aml_equal(rev, aml_int(1)));
+                {
+                    /* revision 1 */
+                    /* PPRQ = op */
+                    aml_append(ifctx3, aml_store(op, pprq));
+                    /* no argument, PPRM = 0 */
+                    aml_append(ifctx3, aml_store(aml_int(0), pprm));
+                }
+                aml_append(ifctx2, ifctx3);
+
+                ifctx3 = aml_if(aml_equal(rev, aml_int(2)));
+                {
+                    /* revision 2 */
+                    /* PPRQ = op */
+                    arguments = aml_arg(3);
+                    op_arg = aml_derefof(aml_index(arguments, aml_int(1)));
+                    aml_append(ifctx3, aml_store(op, pprq));
+                    /* PPRM = arg3[1] */
+                    aml_append(ifctx3, aml_store(op_arg, 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
+             */
+            ifctx2 = aml_if(aml_equal(function, aml_int(8)));
+            {
+                /* get opcode */
+                arguments = aml_arg(3);
+                op = aml_local(0);
+                op_flags = aml_local(1);
+                aml_append(ifctx2,
+                           aml_store(aml_derefof(aml_index(arguments,
+                                                           aml_int(0))),
+                                     op));
+
+                /* get opcode flags */
+                aml_append(ifctx2, aml_store(aml_call1("TPFN", op),
+                                             op_flags));
+                /* 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,
@@ -1802,6 +2193,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
     uint32_t nr_mem = machine->ram_slots;
     int root_bus_limit = 0xFF;
     PCIBus *bus = NULL;
+    TPMIf *tpm = tpm_find();
     int i;
 
     dsdt = init_aml_allocator();
@@ -2139,7 +2531,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
             /* Scan all PCI buses. Generate tables to support hotplug. */
             build_append_pci_bus_devices(scope, bus, pm->pcihp_bridge_en);
 
-            if (TPM_IS_TIS(tpm_find())) {
+            if (TPM_IS_TIS(tpm)) {
                 dev = aml_device("ISA.TPM");
                 aml_append(dev, aml_name_decl("_HID", aml_eisaid("PNP0C31")));
                 aml_append(dev, aml_name_decl("_STA", aml_int(0xF)));
@@ -2153,6 +2545,9 @@ 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(tpm, dev);
+
                 aml_append(scope, dev);
             }
 
@@ -2160,7 +2555,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
         }
     }
 
-    if (TPM_IS_CRB(tpm_find())) {
+    if (TPM_IS_CRB(tpm)) {
         dev = aml_device("TPM");
         aml_append(dev, aml_name_decl("_HID", aml_string("MSFT0101")));
         crs = aml_resource_template();
@@ -2172,6 +2567,8 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
         aml_append(method, aml_return(aml_int(0x0f)));
         aml_append(dev, method);
 
+        build_tpm_ppi(tpm, dev);
+
         aml_append(sb_scope, dev);
     }
 
@@ -2920,7 +3317,7 @@ void acpi_setup(void)
         tpm_config = (FWCfgTPMConfig) {
             .tpmppi_address = cpu_to_le32(TPM_PPI_ADDR_BASE),
             .tpm_version = tpm_get_version(tpm_find()),
-            .tpmppi_version = TPM_PPI_VERSION_NONE
+            .tpmppi_version = 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


Re: [Qemu-devel] [PATCH v6 4/4] acpi: build TPM Physical Presence interface
Posted by Igor Mammedov 7 years, 5 months ago
On Thu, 28 Jun 2018 19:26:57 +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.
> 
> Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
> [ Marc-André - ACPI code improvements and windows fixes ]
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> 
> ---
> 
> v7: (Marc-André)
>  - use first spec version/section in code comments
>  - use more variables for ASL code building
>  - remove unnecessering ToInteger() calls
> 
> 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  | 403 +++++++++++++++++++++++++++++++++++++++++-
>  docs/specs/tpm.txt    |  79 +++++++++
>  3 files changed, 487 insertions(+), 3 deletions(-)
> 
> 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 ebd64c4818..263677f3e4 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 +1790,396 @@ static Aml *build_q35_osc_method(void)
>      return method;
>  }
>  
> +static void
> +build_tpm_ppi(TPMIf *tpm, Aml *dev)
> +{
> +    Aml *method, *field, *ifctx, *ifctx2, *ifctx3;
> +    Aml *pak, *tpm2, *tpm3, *pprm, *pprq;
> +    int i;
> +
> +    if (!object_property_get_bool(OBJECT(tpm), "ppi", &error_abort)) {
> +        return;
> +    }
I'd prefer this being checked by caller, like:

@@ -2194,6 +2194,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
     int root_bus_limit = 0xFF;
     PCIBus *bus = NULL;
     TPMIf *tpm = tpm_find();
+    bool has_ppi = object_property_get_bool(OBJECT(tpm), "ppi", &error_abort);
     int i;
 
     dsdt = init_aml_allocator();
@@ -2545,8 +2546,9 @@ 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(tpm, dev);
+                if (has_ppi) {
+                    build_tpm_ppi(tpm, dev);
+                }
 
                 aml_append(scope, dev);
             }
@@ -2567,7 +2569,9 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
         aml_append(method, aml_return(aml_int(0x0f)));
         aml_append(dev, method);
 
-        build_tpm_ppi(tpm, dev);
+        if (has_ppi) {
+            build_tpm_ppi(tpm, dev);
+        }
 
         aml_append(sb_scope, dev);
     }

> +    /*
> +     * 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);
> +    }
this and TPFN takes more than 4K.
Have you tried to declare only one filed of size TPP1, which makes
field Buffer type, which could be used with Index and would take only
several bytes to in AML. See ACPI 6.2a 19.6.61.2 Index with Buffers.
It also looks very portable (but we should test with win xp just to be safe)

> +    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);
> +    pprq = aml_name("PPRQ");
> +    pprm = aml_name("PPRM");
> +
> +    /*
> +     * 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));
> +    aml_append(dev, aml_name_decl("TPM2", pak));
> +    tpm2 = aml_name("TPM2");
> +
> +    pak = aml_package(3);
> +    aml_append(pak, aml_int(0));
> +    aml_append(pak, aml_int(0));
> +    aml_append(pak, aml_int(0));
> +    aml_append(dev, aml_name_decl("TPM3", pak));
> +    tpm3 = aml_name("TPM3");
looks like above 2 packages  are used only by _DSM,
so you don't need to make them global, just use local variables within _DSM for it

> +
> +    method = aml_method("_DSM", 4, AML_SERIALIZED);
> +    {
> +        uint8_t zerobyte[1] = { 0 }; 
> +        Aml *function, *arguments, *rev, *op, *op_arg, *op_flags, *uuid;
> +
> +        uuid = aml_arg(0);
> +        rev = aml_arg(1);
> +        function = aml_arg(2);
> +        ifctx = aml_if(
> +            aml_equal(uuid,
> +                      aml_touuid("3DDDFAA6-361B-4EB4-A424-8D10089D1653")));
> +        {
it would be better to exit immediately if UUID doesn't match (less indentation and if contexts)
btw, one should return something if uuid doesn't match method,

if (LNotEqual(uuid, ToUUID(“893f00a6-660c-494e-bcfd-3043f4fb67c0”))) {
    return(Buffer(){0})
}

> +            /* standard DSM query function */
> +            ifctx2 = aml_if(aml_equal(function, aml_int(0)));
constants aml_int(0..3) are used multiple times, suggest to declare them
along with rev/function/..., like:

 Aml *one = aml_int(0);
 ...

and then use them through code.


> +            {
> +                uint8_t byte_list[2] = { 0xff, 0x01 };
> +                aml_append(ifctx2, aml_return(aml_buffer(2, byte_list)));
> +            }
> +            aml_append(ifctx, ifctx2);
> +
> +            /*
> +             * PPI 1.0: 2.1.1 Get Physical Presence Interface Version
> +             *
> +             * Arg 2 (Integer): Function Index = 1
> +             * Arg 3 (Package): Arguments = Empty Package
> +             * Returns: Type: String
> +             */
> +            ifctx2 = aml_if(aml_equal(function, aml_int(1)));
> +            {
> +                aml_append(ifctx2, aml_return(aml_string("1.3")));
> +            }
> +            aml_append(ifctx, ifctx2);
> +
> +            /*
> +             * PPI 1.0: 2.1.3 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
> +             */
> +            ifctx2 = aml_if(aml_equal(function, aml_int(2)));
> +            {
> +                /* get opcode */
> +                arguments = aml_arg(3);
> +                op = aml_local(0);
> +                op_flags = aml_local(1);
suggest to move these 3 close to function/rev/... as they are repeated several times
with the same meaning in several if contexts.

> +                aml_append(ifctx2,
> +                           aml_store(aml_derefof(aml_index(arguments,
> +                                                           aml_int(0))), op));
> +
> +                /* get opcode flags */
> +                aml_append(ifctx2,
> +                           aml_store(aml_call1("TPFN", op), op_flags));
> +
> +                /* 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)));
same as for aml_int(0) TPM_PPI_FUNC_MASK/TPM_PPI_FUNC_NOT_IMPLEMENTED and other TPM_PPI_*
constants that are user as aml_int(), it might mkae code more readable with
shorter lines and shorter variable names.

> +                {
> +                    /* 1: Operation Value of the Request Not Supported */
> +                    aml_append(ifctx3, aml_return(aml_int(1)));
> +                }
> +                aml_append(ifctx2, ifctx3);
> +
> +                aml_append(ifctx2, aml_store(op, pprq));
> +                aml_append(ifctx2, aml_store(aml_int(0), pprm));
> +                /* 0: success */
> +                aml_append(ifctx2, aml_return(aml_int(0)));
> +            }
> +            aml_append(ifctx, ifctx2);
> +
> +            /*
> +             * PPI 1.0: 2.1.4 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
> +             */
> +            ifctx2 = aml_if(aml_equal(function, aml_int(3)));
> +            {
> +                /*
> +                 * Revision ID of 1, no integer parameter beyond
> +                 * parameter two are expected
> +                 */
> +                ifctx3 = aml_if(aml_equal(rev, aml_int(1)));
> +                {
> +                    /* TPM2[1] = PPRQ */
> +                    aml_append(ifctx3,
> +                               aml_store(pprq, aml_index(tpm2, aml_int(1))));
> +                    aml_append(ifctx3, aml_return(tpm2));
> +                }
> +                aml_append(ifctx2, ifctx3);
> +
> +                /*
> +                 * A return value of {0, 23, 1} indicates that
> +                 * operation 23 with argument 1 is pending.
> +                 */
> +                ifctx3 = aml_if(aml_equal(rev, aml_int(2)));
> +                {
> +                    /* TPM3[1] = PPRQ */
> +                    aml_append(ifctx3,
> +                               aml_store(pprq, aml_index(tpm3, aml_int(1))));
> +                    /* TPM3[2] = PPRM */
> +                    aml_append(ifctx3,
> +                               aml_store(pprm, aml_index(tpm3, aml_int(2))));
> +                    aml_append(ifctx3, aml_return(tpm3));
> +                }
> +                aml_append(ifctx2, ifctx3);
> +            }
> +            aml_append(ifctx, ifctx2);
> +
> +            /*
> +             * PPI 1.0: 2.1.5 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
> +             */
> +            ifctx2 = aml_if(aml_equal(function, aml_int(4)));
> +            {
> +                /* reboot */
> +                aml_append(ifctx2, aml_return(aml_int(2)));
> +            }
> +            aml_append(ifctx, ifctx2);
> +
> +            /*
> +             * PPI 1.0: 2.1.6 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
> +             */
> +            ifctx2 = aml_if(aml_equal(function, aml_int(5)));
> +            {
> +                /* TPM3[1] = LPPR */
> +                aml_append(ifctx2,
> +                           aml_store(aml_name("LPPR"),
> +                                     aml_index(tpm3, aml_int(1))));
> +                /* TPM3[2] = PPRP */
> +                aml_append(ifctx2,
> +                           aml_store(aml_name("PPRP"),
> +                                     aml_index(tpm3, aml_int(2))));
> +                aml_append(ifctx2, aml_return(tpm3));
> +            }
> +            aml_append(ifctx, ifctx2);
> +
> +            /*
> +             * PPI 1.0: 2.1.7 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
> +             */
> +            ifctx2 = aml_if(aml_equal(function, aml_int(6)));
> +            {
> +                /* 3 = not implemented */
> +                aml_append(ifctx2, aml_return(aml_int(3)));
> +            }
> +            aml_append(ifctx, ifctx2);
> +
> +            /*
> +             * PPI 1.1: 2.1.7 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
> +             */
> +            ifctx2 = aml_if(aml_equal(function, aml_int(7)));
> +            {
> +                /* get opcode */
> +                arguments = aml_arg(3);
> +                op = aml_local(0);
> +                op_flags = aml_local(1);
> +                aml_append(ifctx2, aml_store(aml_derefof(aml_index(arguments,
> +                                                                   aml_int(0))),
> +                                             op));
> +
> +                /* get opcode flags */
> +                aml_append(ifctx2, aml_store(aml_call1("TPFN", op),
> +                                             op_flags));
> +                /* 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);
> +
> +                /* if func[opcode] & TPM_PPI_FUNC_BLOCKED */
> +                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 */
> +                ifctx3 = aml_if(aml_equal(rev, aml_int(1)));
> +                {
> +                    /* revision 1 */
> +                    /* PPRQ = op */
> +                    aml_append(ifctx3, aml_store(op, pprq));
> +                    /* no argument, PPRM = 0 */
> +                    aml_append(ifctx3, aml_store(aml_int(0), pprm));
> +                }
> +                aml_append(ifctx2, ifctx3);
> +
> +                ifctx3 = aml_if(aml_equal(rev, aml_int(2)));
> +                {
> +                    /* revision 2 */
> +                    /* PPRQ = op */
> +                    arguments = aml_arg(3);
> +                    op_arg = aml_derefof(aml_index(arguments, aml_int(1)));
> +                    aml_append(ifctx3, aml_store(op, pprq));
> +                    /* PPRM = arg3[1] */
> +                    aml_append(ifctx3, aml_store(op_arg, 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
> +             */
> +            ifctx2 = aml_if(aml_equal(function, aml_int(8)));
> +            {
> +                /* get opcode */
> +                arguments = aml_arg(3);
> +                op = aml_local(0);
> +                op_flags = aml_local(1);
> +                aml_append(ifctx2,
> +                           aml_store(aml_derefof(aml_index(arguments,
> +                                                           aml_int(0))),
> +                                     op));
> +
> +                /* get opcode flags */
> +                aml_append(ifctx2, aml_store(aml_call1("TPFN", op),
> +                                             op_flags));
> +                /* 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,
> @@ -1802,6 +2193,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
>      uint32_t nr_mem = machine->ram_slots;
>      int root_bus_limit = 0xFF;
>      PCIBus *bus = NULL;
> +    TPMIf *tpm = tpm_find();
>      int i;
>  
>      dsdt = init_aml_allocator();
> @@ -2139,7 +2531,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
>              /* Scan all PCI buses. Generate tables to support hotplug. */
>              build_append_pci_bus_devices(scope, bus, pm->pcihp_bridge_en);
>  
> -            if (TPM_IS_TIS(tpm_find())) {
> +            if (TPM_IS_TIS(tpm)) {
>                  dev = aml_device("ISA.TPM");
>                  aml_append(dev, aml_name_decl("_HID", aml_eisaid("PNP0C31")));
>                  aml_append(dev, aml_name_decl("_STA", aml_int(0xF)));
> @@ -2153,6 +2545,9 @@ 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(tpm, dev);
> +
>                  aml_append(scope, dev);
>              }
>  
> @@ -2160,7 +2555,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
>          }
>      }
>  
> -    if (TPM_IS_CRB(tpm_find())) {
> +    if (TPM_IS_CRB(tpm)) {
>          dev = aml_device("TPM");
>          aml_append(dev, aml_name_decl("_HID", aml_string("MSFT0101")));
>          crs = aml_resource_template();
> @@ -2172,6 +2567,8 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
>          aml_append(method, aml_return(aml_int(0x0f)));
>          aml_append(dev, method);
>  
> +        build_tpm_ppi(tpm, dev);
> +
>          aml_append(sb_scope, dev);
>      }
>  
> @@ -2920,7 +3317,7 @@ void acpi_setup(void)
>          tpm_config = (FWCfgTPMConfig) {
>              .tpmppi_address = cpu_to_le32(TPM_PPI_ADDR_BASE),
>              .tpm_version = tpm_get_version(tpm_find()),
> -            .tpmppi_version = TPM_PPI_VERSION_NONE
> +            .tpmppi_version = 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


Re: [Qemu-devel] [PATCH v6 4/4] acpi: build TPM Physical Presence interface
Posted by Marc-André Lureau 7 years, 5 months ago
HI

On Wed, Jul 4, 2018 at 5:39 PM, Igor Mammedov <imammedo@redhat.com> wrote:
> On Thu, 28 Jun 2018 19:26:57 +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.
>>
>> Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
>> [ Marc-André - ACPI code improvements and windows fixes ]
>> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
>>
>> ---
>>
>> v7: (Marc-André)
>>  - use first spec version/section in code comments
>>  - use more variables for ASL code building
>>  - remove unnecessering ToInteger() calls
>>
>> 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  | 403 +++++++++++++++++++++++++++++++++++++++++-
>>  docs/specs/tpm.txt    |  79 +++++++++
>>  3 files changed, 487 insertions(+), 3 deletions(-)
>>
>> 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 ebd64c4818..263677f3e4 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 +1790,396 @@ static Aml *build_q35_osc_method(void)
>>      return method;
>>  }
>>
>> +static void
>> +build_tpm_ppi(TPMIf *tpm, Aml *dev)
>> +{
>> +    Aml *method, *field, *ifctx, *ifctx2, *ifctx3;
>> +    Aml *pak, *tpm2, *tpm3, *pprm, *pprq;
>> +    int i;
>> +
>> +    if (!object_property_get_bool(OBJECT(tpm), "ppi", &error_abort)) {
>> +        return;
>> +    }
> I'd prefer this being checked by caller, like:
>
> @@ -2194,6 +2194,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
>      int root_bus_limit = 0xFF;
>      PCIBus *bus = NULL;
>      TPMIf *tpm = tpm_find();
> +    bool has_ppi = object_property_get_bool(OBJECT(tpm), "ppi", &error_abort);

it will need an additional "tpm ? .. : false". I'd rather keep it away
from build_dsdt(), but your call.

>      int i;
>
>      dsdt = init_aml_allocator();
> @@ -2545,8 +2546,9 @@ 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(tpm, dev);
> +                if (has_ppi) {
> +                    build_tpm_ppi(tpm, dev);
> +                }
>
>                  aml_append(scope, dev);
>              }
> @@ -2567,7 +2569,9 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
>          aml_append(method, aml_return(aml_int(0x0f)));
>          aml_append(dev, method);
>
> -        build_tpm_ppi(tpm, dev);
> +        if (has_ppi) {
> +            build_tpm_ppi(tpm, dev);
> +        }
>
>          aml_append(sb_scope, dev);
>      }
>
>> +    /*
>> +     * 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);
>> +    }
> this and TPFN takes more than 4K.
> Have you tried to declare only one filed of size TPP1, which makes
> field Buffer type, which could be used with Index and would take only
> several bytes to in AML. See ACPI 6.2a 19.6.61.2 Index with Buffers.
> It also looks very portable (but we should test with win xp just to be safe)

You mean like Stefan originally did? Yes, problem described in
http://www.osronline.com/showThread.CFM?link=288617.

>
>> +    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);
>> +    pprq = aml_name("PPRQ");
>> +    pprm = aml_name("PPRM");
>> +
>> +    /*
>> +     * 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));
>> +    aml_append(dev, aml_name_decl("TPM2", pak));
>> +    tpm2 = aml_name("TPM2");
>> +
>> +    pak = aml_package(3);
>> +    aml_append(pak, aml_int(0));
>> +    aml_append(pak, aml_int(0));
>> +    aml_append(pak, aml_int(0));
>> +    aml_append(dev, aml_name_decl("TPM3", pak));
>> +    tpm3 = aml_name("TPM3");
> looks like above 2 packages  are used only by _DSM,
> so you don't need to make them global, just use local variables within _DSM for it
>

That would also fail on Windows. Fwiw (this time I am sure) my up to
date t460p uses the same global variables trick, presumably to satisfy
Windows as well.

btw, not only it took me a while to find the shortcomings with Windows
ACPI, but testing any change in the ACPI code takes ~1.5h (with manual
intervention ever 10 minutes or so, not a lot of fun)

>> +
>> +    method = aml_method("_DSM", 4, AML_SERIALIZED);
>> +    {
>> +        uint8_t zerobyte[1] = { 0 };
>> +        Aml *function, *arguments, *rev, *op, *op_arg, *op_flags, *uuid;
>> +
>> +        uuid = aml_arg(0);
>> +        rev = aml_arg(1);
>> +        function = aml_arg(2);
>> +        ifctx = aml_if(
>> +            aml_equal(uuid,
>> +                      aml_touuid("3DDDFAA6-361B-4EB4-A424-8D10089D1653")));
>> +        {
> it would be better to exit immediately if UUID doesn't match (less indentation and if contexts)
> btw, one should return something if uuid doesn't match method,
>
> if (LNotEqual(uuid, ToUUID(“893f00a6-660c-494e-bcfd-3043f4fb67c0”))) {
>     return(Buffer(){0})
> }
>

Except that the next patch has another uuid to check (and it's not a
common ACPI style to return early it seems).

>> +            /* standard DSM query function */
>> +            ifctx2 = aml_if(aml_equal(function, aml_int(0)));
> constants aml_int(0..3) are used multiple times, suggest to declare them
> along with rev/function/..., like:
>
>  Aml *one = aml_int(0);
>  ...
>
> and then use them through code.

I don't see that as an improvement tbh, it makes the code
inconsistent. So you would like to have zero and one, but not others?
ok, at this point I don't think I care enough :).

>
>
>> +            {
>> +                uint8_t byte_list[2] = { 0xff, 0x01 };
>> +                aml_append(ifctx2, aml_return(aml_buffer(2, byte_list)));
>> +            }
>> +            aml_append(ifctx, ifctx2);
>> +
>> +            /*
>> +             * PPI 1.0: 2.1.1 Get Physical Presence Interface Version
>> +             *
>> +             * Arg 2 (Integer): Function Index = 1
>> +             * Arg 3 (Package): Arguments = Empty Package
>> +             * Returns: Type: String
>> +             */
>> +            ifctx2 = aml_if(aml_equal(function, aml_int(1)));
>> +            {
>> +                aml_append(ifctx2, aml_return(aml_string("1.3")));
>> +            }
>> +            aml_append(ifctx, ifctx2);
>> +
>> +            /*
>> +             * PPI 1.0: 2.1.3 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
>> +             */
>> +            ifctx2 = aml_if(aml_equal(function, aml_int(2)));
>> +            {
>> +                /* get opcode */
>> +                arguments = aml_arg(3);
>> +                op = aml_local(0);
>> +                op_flags = aml_local(1);
> suggest to move these 3 close to function/rev/... as they are repeated several times
> with the same meaning in several if contexts.

ok

>
>> +                aml_append(ifctx2,
>> +                           aml_store(aml_derefof(aml_index(arguments,
>> +                                                           aml_int(0))), op));
>> +
>> +                /* get opcode flags */
>> +                aml_append(ifctx2,
>> +                           aml_store(aml_call1("TPFN", op), op_flags));
>> +
>> +                /* 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)));
> same as for aml_int(0) TPM_PPI_FUNC_MASK/TPM_PPI_FUNC_NOT_IMPLEMENTED and other TPM_PPI_*
> constants that are user as aml_int(), it might mkae code more readable with
> shorter lines and shorter variable names.

ok

>
>> +                {
>> +                    /* 1: Operation Value of the Request Not Supported */
>> +                    aml_append(ifctx3, aml_return(aml_int(1)));
>> +                }
>> +                aml_append(ifctx2, ifctx3);
>> +
>> +                aml_append(ifctx2, aml_store(op, pprq));
>> +                aml_append(ifctx2, aml_store(aml_int(0), pprm));
>> +                /* 0: success */
>> +                aml_append(ifctx2, aml_return(aml_int(0)));
>> +            }
>> +            aml_append(ifctx, ifctx2);
>> +
>> +            /*
>> +             * PPI 1.0: 2.1.4 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
>> +             */
>> +            ifctx2 = aml_if(aml_equal(function, aml_int(3)));
>> +            {
>> +                /*
>> +                 * Revision ID of 1, no integer parameter beyond
>> +                 * parameter two are expected
>> +                 */
>> +                ifctx3 = aml_if(aml_equal(rev, aml_int(1)));
>> +                {
>> +                    /* TPM2[1] = PPRQ */
>> +                    aml_append(ifctx3,
>> +                               aml_store(pprq, aml_index(tpm2, aml_int(1))));
>> +                    aml_append(ifctx3, aml_return(tpm2));
>> +                }
>> +                aml_append(ifctx2, ifctx3);
>> +
>> +                /*
>> +                 * A return value of {0, 23, 1} indicates that
>> +                 * operation 23 with argument 1 is pending.
>> +                 */
>> +                ifctx3 = aml_if(aml_equal(rev, aml_int(2)));
>> +                {
>> +                    /* TPM3[1] = PPRQ */
>> +                    aml_append(ifctx3,
>> +                               aml_store(pprq, aml_index(tpm3, aml_int(1))));
>> +                    /* TPM3[2] = PPRM */
>> +                    aml_append(ifctx3,
>> +                               aml_store(pprm, aml_index(tpm3, aml_int(2))));
>> +                    aml_append(ifctx3, aml_return(tpm3));
>> +                }
>> +                aml_append(ifctx2, ifctx3);
>> +            }
>> +            aml_append(ifctx, ifctx2);
>> +
>> +            /*
>> +             * PPI 1.0: 2.1.5 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
>> +             */
>> +            ifctx2 = aml_if(aml_equal(function, aml_int(4)));
>> +            {
>> +                /* reboot */
>> +                aml_append(ifctx2, aml_return(aml_int(2)));
>> +            }
>> +            aml_append(ifctx, ifctx2);
>> +
>> +            /*
>> +             * PPI 1.0: 2.1.6 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
>> +             */
>> +            ifctx2 = aml_if(aml_equal(function, aml_int(5)));
>> +            {
>> +                /* TPM3[1] = LPPR */
>> +                aml_append(ifctx2,
>> +                           aml_store(aml_name("LPPR"),
>> +                                     aml_index(tpm3, aml_int(1))));
>> +                /* TPM3[2] = PPRP */
>> +                aml_append(ifctx2,
>> +                           aml_store(aml_name("PPRP"),
>> +                                     aml_index(tpm3, aml_int(2))));
>> +                aml_append(ifctx2, aml_return(tpm3));
>> +            }
>> +            aml_append(ifctx, ifctx2);
>> +
>> +            /*
>> +             * PPI 1.0: 2.1.7 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
>> +             */
>> +            ifctx2 = aml_if(aml_equal(function, aml_int(6)));
>> +            {
>> +                /* 3 = not implemented */
>> +                aml_append(ifctx2, aml_return(aml_int(3)));
>> +            }
>> +            aml_append(ifctx, ifctx2);
>> +
>> +            /*
>> +             * PPI 1.1: 2.1.7 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
>> +             */
>> +            ifctx2 = aml_if(aml_equal(function, aml_int(7)));
>> +            {
>> +                /* get opcode */
>> +                arguments = aml_arg(3);
>> +                op = aml_local(0);
>> +                op_flags = aml_local(1);
>> +                aml_append(ifctx2, aml_store(aml_derefof(aml_index(arguments,
>> +                                                                   aml_int(0))),
>> +                                             op));
>> +
>> +                /* get opcode flags */
>> +                aml_append(ifctx2, aml_store(aml_call1("TPFN", op),
>> +                                             op_flags));
>> +                /* 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);
>> +
>> +                /* if func[opcode] & TPM_PPI_FUNC_BLOCKED */
>> +                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 */
>> +                ifctx3 = aml_if(aml_equal(rev, aml_int(1)));
>> +                {
>> +                    /* revision 1 */
>> +                    /* PPRQ = op */
>> +                    aml_append(ifctx3, aml_store(op, pprq));
>> +                    /* no argument, PPRM = 0 */
>> +                    aml_append(ifctx3, aml_store(aml_int(0), pprm));
>> +                }
>> +                aml_append(ifctx2, ifctx3);
>> +
>> +                ifctx3 = aml_if(aml_equal(rev, aml_int(2)));
>> +                {
>> +                    /* revision 2 */
>> +                    /* PPRQ = op */
>> +                    arguments = aml_arg(3);
>> +                    op_arg = aml_derefof(aml_index(arguments, aml_int(1)));
>> +                    aml_append(ifctx3, aml_store(op, pprq));
>> +                    /* PPRM = arg3[1] */
>> +                    aml_append(ifctx3, aml_store(op_arg, 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
>> +             */
>> +            ifctx2 = aml_if(aml_equal(function, aml_int(8)));
>> +            {
>> +                /* get opcode */
>> +                arguments = aml_arg(3);
>> +                op = aml_local(0);
>> +                op_flags = aml_local(1);
>> +                aml_append(ifctx2,
>> +                           aml_store(aml_derefof(aml_index(arguments,
>> +                                                           aml_int(0))),
>> +                                     op));
>> +
>> +                /* get opcode flags */
>> +                aml_append(ifctx2, aml_store(aml_call1("TPFN", op),
>> +                                             op_flags));
>> +                /* 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,
>> @@ -1802,6 +2193,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
>>      uint32_t nr_mem = machine->ram_slots;
>>      int root_bus_limit = 0xFF;
>>      PCIBus *bus = NULL;
>> +    TPMIf *tpm = tpm_find();
>>      int i;
>>
>>      dsdt = init_aml_allocator();
>> @@ -2139,7 +2531,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
>>              /* Scan all PCI buses. Generate tables to support hotplug. */
>>              build_append_pci_bus_devices(scope, bus, pm->pcihp_bridge_en);
>>
>> -            if (TPM_IS_TIS(tpm_find())) {
>> +            if (TPM_IS_TIS(tpm)) {
>>                  dev = aml_device("ISA.TPM");
>>                  aml_append(dev, aml_name_decl("_HID", aml_eisaid("PNP0C31")));
>>                  aml_append(dev, aml_name_decl("_STA", aml_int(0xF)));
>> @@ -2153,6 +2545,9 @@ 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(tpm, dev);
>> +
>>                  aml_append(scope, dev);
>>              }
>>
>> @@ -2160,7 +2555,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
>>          }
>>      }
>>
>> -    if (TPM_IS_CRB(tpm_find())) {
>> +    if (TPM_IS_CRB(tpm)) {
>>          dev = aml_device("TPM");
>>          aml_append(dev, aml_name_decl("_HID", aml_string("MSFT0101")));
>>          crs = aml_resource_template();
>> @@ -2172,6 +2567,8 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
>>          aml_append(method, aml_return(aml_int(0x0f)));
>>          aml_append(dev, method);
>>
>> +        build_tpm_ppi(tpm, dev);
>> +
>>          aml_append(sb_scope, dev);
>>      }
>>
>> @@ -2920,7 +3317,7 @@ void acpi_setup(void)
>>          tpm_config = (FWCfgTPMConfig) {
>>              .tpmppi_address = cpu_to_le32(TPM_PPI_ADDR_BASE),
>>              .tpm_version = tpm_get_version(tpm_find()),
>> -            .tpmppi_version = TPM_PPI_VERSION_NONE
>> +            .tpmppi_version = 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
>
>



-- 
Marc-André Lureau

Re: [Qemu-devel] [PATCH v6 4/4] acpi: build TPM Physical Presence interface
Posted by Igor Mammedov 7 years, 5 months ago
On Wed, 4 Jul 2018 18:00:41 +0200
Marc-André Lureau <marcandre.lureau@gmail.com> wrote:

> HI
> 
> On Wed, Jul 4, 2018 at 5:39 PM, Igor Mammedov <imammedo@redhat.com> wrote:
> > On Thu, 28 Jun 2018 19:26:57 +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.
> >>
> >> Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
> >> [ Marc-André - ACPI code improvements and windows fixes ]
> >> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> >>
> >> ---
> >>
> >> v7: (Marc-André)
> >>  - use first spec version/section in code comments
> >>  - use more variables for ASL code building
> >>  - remove unnecessering ToInteger() calls
> >>
> >> 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  | 403 +++++++++++++++++++++++++++++++++++++++++-
> >>  docs/specs/tpm.txt    |  79 +++++++++
> >>  3 files changed, 487 insertions(+), 3 deletions(-)
> >>
> >> 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 ebd64c4818..263677f3e4 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 +1790,396 @@ static Aml *build_q35_osc_method(void)
> >>      return method;
> >>  }
> >>
> >> +static void
> >> +build_tpm_ppi(TPMIf *tpm, Aml *dev)
> >> +{
> >> +    Aml *method, *field, *ifctx, *ifctx2, *ifctx3;
> >> +    Aml *pak, *tpm2, *tpm3, *pprm, *pprq;
> >> +    int i;
> >> +
> >> +    if (!object_property_get_bool(OBJECT(tpm), "ppi", &error_abort)) {
> >> +        return;
> >> +    }  
> > I'd prefer this being checked by caller, like:
> >
> > @@ -2194,6 +2194,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
> >      int root_bus_limit = 0xFF;
> >      PCIBus *bus = NULL;
> >      TPMIf *tpm = tpm_find();
> > +    bool has_ppi = object_property_get_bool(OBJECT(tpm), "ppi", &error_abort);  
> 
> it will need an additional "tpm ? .. : false". I'd rather keep it away
> from build_dsdt(), but your call.
ok, keep it as it is now

> 
> >      int i;
> >
> >      dsdt = init_aml_allocator();
> > @@ -2545,8 +2546,9 @@ 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(tpm, dev);
> > +                if (has_ppi) {
> > +                    build_tpm_ppi(tpm, dev);
> > +                }
> >
> >                  aml_append(scope, dev);
> >              }
> > @@ -2567,7 +2569,9 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
> >          aml_append(method, aml_return(aml_int(0x0f)));
> >          aml_append(dev, method);
> >
> > -        build_tpm_ppi(tpm, dev);
> > +        if (has_ppi) {
> > +            build_tpm_ppi(tpm, dev);
> > +        }
> >
> >          aml_append(sb_scope, dev);
> >      }
> >  
> >> +    /*
> >> +     * 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);
> >> +    }  
> > this and TPFN takes more than 4K.
> > Have you tried to declare only one filed of size TPP1, which makes
> > field Buffer type, which could be used with Index and would take only
> > several bytes to in AML. See ACPI 6.2a 19.6.61.2 Index with Buffers.
> > It also looks very portable (but we should test with win xp just to be safe)  
> 
> You mean like Stefan originally did? Yes, problem described in
> http://www.osronline.com/showThread.CFM?link=288617.

we have cpu hotplug that uses this approach, but it has IO based OpReg.

Looks like DerefOf in windows is broken wrt SYSTEM_MEMORY originated field buffer
(debugger shows a correct object returned from Index() but DerefOf reads
junk, sometimes it returns the last byte of buffer address).

but do not give up yet,
one can use dynamic operation region inside of method for indexing
so here goes dirty draft idea:
    TPFN(op)
        aml_append(method, aml_operation_region(
          "TPP1",
          AML_SYSTEM_MEMORY,
          aml_add(aml_int(TPM_PPI_ADDR_BASE), op, NULL),
          0x1));
        field = aml_field("TPP1", AML_BYTE_ACC, AML_NOLOCK, AML_PRESERVE);       
        aml_append(field, aml_named_field("TPPF", 8));                           
        aml_append(method, field);                                               
        aml_append(method, aml_return(aml_name("TPPF")));

result of addition probably should be stored in sanely named local var,
but idea stays the same (use address in OpRegion as index) and if 'op'
is user defined, we probably should have bounds check as well.

I don't like dynamic OpRegions but in general, but it savs us a lot of RAM
and much faster then walking 'if..else' chain multiple times.


> >  
> >> +    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);
> >> +    pprq = aml_name("PPRQ");
> >> +    pprm = aml_name("PPRM");
> >> +
> >> +    /*
> >> +     * 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));
> >> +    aml_append(dev, aml_name_decl("TPM2", pak));
> >> +    tpm2 = aml_name("TPM2");
> >> +
> >> +    pak = aml_package(3);
> >> +    aml_append(pak, aml_int(0));
> >> +    aml_append(pak, aml_int(0));
> >> +    aml_append(pak, aml_int(0));
> >> +    aml_append(dev, aml_name_decl("TPM3", pak));
> >> +    tpm3 = aml_name("TPM3");  
> > looks like above 2 packages  are used only by _DSM,
> > so you don't need to make them global, just use local variables within _DSM for it
> >  
> 
> That would also fail on Windows. Fwiw (this time I am sure) my up to
> date t460p uses the same global variables trick, presumably to satisfy
> Windows as well.
ok, could you add a comment about it here so that we won't optimize it
out in future.

> btw, not only it took me a while to find the shortcomings with Windows
> ACPI, but testing any change in the ACPI code takes ~1.5h (with manual
> intervention ever 10 minutes or so, not a lot of fun)
don't tell me, I just killed a bunch of time first to setup debug
environment with broken serial for this series and then to
find a solution that would work (~15min per ACPI change)

> 
> >> +
> >> +    method = aml_method("_DSM", 4, AML_SERIALIZED);
> >> +    {
> >> +        uint8_t zerobyte[1] = { 0 };
> >> +        Aml *function, *arguments, *rev, *op, *op_arg, *op_flags, *uuid;
> >> +
> >> +        uuid = aml_arg(0);
> >> +        rev = aml_arg(1);
> >> +        function = aml_arg(2);
> >> +        ifctx = aml_if(
> >> +            aml_equal(uuid,
> >> +                      aml_touuid("3DDDFAA6-361B-4EB4-A424-8D10089D1653")));
> >> +        {  
> > it would be better to exit immediately if UUID doesn't match (less indentation and if contexts)
> > btw, one should return something if uuid doesn't match method,
> >
> > if (LNotEqual(uuid, ToUUID(“893f00a6-660c-494e-bcfd-3043f4fb67c0”))) {
> >     return(Buffer(){0})
> > }
> >  
> 
> Except that the next patch has another uuid to check (and it's not a
> common ACPI style to return early it seems).
ok, keep it as is

> 
> >> +            /* standard DSM query function */
> >> +            ifctx2 = aml_if(aml_equal(function, aml_int(0)));  
> > constants aml_int(0..3) are used multiple times, suggest to declare them
> > along with rev/function/..., like:
> >
> >  Aml *one = aml_int(0);
> >  ...
> >
> > and then use them through code.  
> 
> I don't see that as an improvement tbh, it makes the code
> inconsistent. So you would like to have zero and one, but not others?
it will be consistent with cpu/mem hotplug ACPI code and ASL
since 0 and 1 have their own magic names (Zero, One) in gramar

[...]

Re: [Qemu-devel] [PATCH v6 4/4] acpi: build TPM Physical Presence interface
Posted by Marc-André Lureau 7 years, 5 months ago
Hi

On Wed, Jul 11, 2018 at 6:25 PM, Igor Mammedov <imammedo@redhat.com> wrote:
> On Wed, 4 Jul 2018 18:00:41 +0200
> Marc-André Lureau <marcandre.lureau@gmail.com> wrote:
>
>> HI
>>
>> On Wed, Jul 4, 2018 at 5:39 PM, Igor Mammedov <imammedo@redhat.com> wrote:
>> > On Thu, 28 Jun 2018 19:26:57 +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.
>> >>
>> >> Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
>> >> [ Marc-André - ACPI code improvements and windows fixes ]
>> >> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
>> >>
>> >> ---
>> >>
>> >> v7: (Marc-André)
>> >>  - use first spec version/section in code comments
>> >>  - use more variables for ASL code building
>> >>  - remove unnecessering ToInteger() calls
>> >>
>> >> 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  | 403 +++++++++++++++++++++++++++++++++++++++++-
>> >>  docs/specs/tpm.txt    |  79 +++++++++
>> >>  3 files changed, 487 insertions(+), 3 deletions(-)
>> >>
>> >> 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 ebd64c4818..263677f3e4 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 +1790,396 @@ static Aml *build_q35_osc_method(void)
>> >>      return method;
>> >>  }
>> >>
>> >> +static void
>> >> +build_tpm_ppi(TPMIf *tpm, Aml *dev)
>> >> +{
>> >> +    Aml *method, *field, *ifctx, *ifctx2, *ifctx3;
>> >> +    Aml *pak, *tpm2, *tpm3, *pprm, *pprq;
>> >> +    int i;
>> >> +
>> >> +    if (!object_property_get_bool(OBJECT(tpm), "ppi", &error_abort)) {
>> >> +        return;
>> >> +    }
>> > I'd prefer this being checked by caller, like:
>> >
>> > @@ -2194,6 +2194,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
>> >      int root_bus_limit = 0xFF;
>> >      PCIBus *bus = NULL;
>> >      TPMIf *tpm = tpm_find();
>> > +    bool has_ppi = object_property_get_bool(OBJECT(tpm), "ppi", &error_abort);
>>
>> it will need an additional "tpm ? .. : false". I'd rather keep it away
>> from build_dsdt(), but your call.
> ok, keep it as it is now
>
>>
>> >      int i;
>> >
>> >      dsdt = init_aml_allocator();
>> > @@ -2545,8 +2546,9 @@ 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(tpm, dev);
>> > +                if (has_ppi) {
>> > +                    build_tpm_ppi(tpm, dev);
>> > +                }
>> >
>> >                  aml_append(scope, dev);
>> >              }
>> > @@ -2567,7 +2569,9 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
>> >          aml_append(method, aml_return(aml_int(0x0f)));
>> >          aml_append(dev, method);
>> >
>> > -        build_tpm_ppi(tpm, dev);
>> > +        if (has_ppi) {
>> > +            build_tpm_ppi(tpm, dev);
>> > +        }
>> >
>> >          aml_append(sb_scope, dev);
>> >      }
>> >
>> >> +    /*
>> >> +     * 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);
>> >> +    }
>> > this and TPFN takes more than 4K.
>> > Have you tried to declare only one filed of size TPP1, which makes
>> > field Buffer type, which could be used with Index and would take only
>> > several bytes to in AML. See ACPI 6.2a 19.6.61.2 Index with Buffers.
>> > It also looks very portable (but we should test with win xp just to be safe)
>>
>> You mean like Stefan originally did? Yes, problem described in
>> http://www.osronline.com/showThread.CFM?link=288617.
>
> we have cpu hotplug that uses this approach, but it has IO based OpReg.
>
> Looks like DerefOf in windows is broken wrt SYSTEM_MEMORY originated field buffer
> (debugger shows a correct object returned from Index() but DerefOf reads
> junk, sometimes it returns the last byte of buffer address).
>
> but do not give up yet,
> one can use dynamic operation region inside of method for indexing
> so here goes dirty draft idea:
>     TPFN(op)
>         aml_append(method, aml_operation_region(
>           "TPP1",
>           AML_SYSTEM_MEMORY,
>           aml_add(aml_int(TPM_PPI_ADDR_BASE), op, NULL),
>           0x1));
>         field = aml_field("TPP1", AML_BYTE_ACC, AML_NOLOCK, AML_PRESERVE);
>         aml_append(field, aml_named_field("TPPF", 8));
>         aml_append(method, field);
>         aml_append(method, aml_return(aml_name("TPPF")));
>
> result of addition probably should be stored in sanely named local var,
> but idea stays the same (use address in OpRegion as index) and if 'op'
> is user defined, we probably should have bounds check as well.
>
> I don't like dynamic OpRegions but in general, but it savs us a lot of RAM
> and much faster then walking 'if..else' chain multiple times.

Awesome! that works, thanks for the trick.

>
>
>> >
>> >> +    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);
>> >> +    pprq = aml_name("PPRQ");
>> >> +    pprm = aml_name("PPRM");
>> >> +
>> >> +    /*
>> >> +     * 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));
>> >> +    aml_append(dev, aml_name_decl("TPM2", pak));
>> >> +    tpm2 = aml_name("TPM2");
>> >> +
>> >> +    pak = aml_package(3);
>> >> +    aml_append(pak, aml_int(0));
>> >> +    aml_append(pak, aml_int(0));
>> >> +    aml_append(pak, aml_int(0));
>> >> +    aml_append(dev, aml_name_decl("TPM3", pak));
>> >> +    tpm3 = aml_name("TPM3");
>> > looks like above 2 packages  are used only by _DSM,
>> > so you don't need to make them global, just use local variables within _DSM for it
>> >
>>
>> That would also fail on Windows. Fwiw (this time I am sure) my up to
>> date t460p uses the same global variables trick, presumably to satisfy
>> Windows as well.
> ok, could you add a comment about it here so that we won't optimize it
> out in future.
>
>> btw, not only it took me a while to find the shortcomings with Windows
>> ACPI, but testing any change in the ACPI code takes ~1.5h (with manual
>> intervention ever 10 minutes or so, not a lot of fun)
> don't tell me, I just killed a bunch of time first to setup debug
> environment with broken serial for this series and then to
> find a solution that would work (~15min per ACPI change)
>
>>
>> >> +
>> >> +    method = aml_method("_DSM", 4, AML_SERIALIZED);
>> >> +    {
>> >> +        uint8_t zerobyte[1] = { 0 };
>> >> +        Aml *function, *arguments, *rev, *op, *op_arg, *op_flags, *uuid;
>> >> +
>> >> +        uuid = aml_arg(0);
>> >> +        rev = aml_arg(1);
>> >> +        function = aml_arg(2);
>> >> +        ifctx = aml_if(
>> >> +            aml_equal(uuid,
>> >> +                      aml_touuid("3DDDFAA6-361B-4EB4-A424-8D10089D1653")));
>> >> +        {
>> > it would be better to exit immediately if UUID doesn't match (less indentation and if contexts)
>> > btw, one should return something if uuid doesn't match method,
>> >
>> > if (LNotEqual(uuid, ToUUID(“893f00a6-660c-494e-bcfd-3043f4fb67c0”))) {
>> >     return(Buffer(){0})
>> > }
>> >
>>
>> Except that the next patch has another uuid to check (and it's not a
>> common ACPI style to return early it seems).
> ok, keep it as is
>
>>
>> >> +            /* standard DSM query function */
>> >> +            ifctx2 = aml_if(aml_equal(function, aml_int(0)));
>> > constants aml_int(0..3) are used multiple times, suggest to declare them
>> > along with rev/function/..., like:
>> >
>> >  Aml *one = aml_int(0);
>> >  ...
>> >
>> > and then use them through code.
>>
>> I don't see that as an improvement tbh, it makes the code
>> inconsistent. So you would like to have zero and one, but not others?
> it will be consistent with cpu/mem hotplug ACPI code and ASL
> since 0 and 1 have their own magic names (Zero, One) in gramar
>

Ok, changed.

thanks



-- 
Marc-André Lureau