The following series of patches adds vTPM emulator support for the
ppc64 platform (pSeries). 

It can be tested as follows with swtpm/libtpms:

mkdir /tmp/mytpm1
swtpm socket --tpmstate dir=/tmp/mytpm1 \
  --ctrl type=unixio,path=/tmp/mytpm1/swtpm-sock \
  --log level=20

If TPM 2 is desired, add --tpm2 as parameter to the above.

In another terminal start QEMU:

sudo ./ppc64-softmmu/qemu-system-ppc64 -display sdl \
	-machine pseries,accel=kvm \
	-m 1024 -bios slof.bin -boot menu=on \
	-nodefaults -device VGA -device pci-ohci -device usb-kbd \
	-chardev socket,id=chrtpm,path=/tmp/mytpm1/swtpm-sock \
	-tpmdev emulator,id=tpm0,chardev=chrtpm \
	-device tpm-spapr,tpmdev=tpm0 \
	-device spapr-vscsi,id=scsi0,reg=0x00002000 \
	-device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x3,drive=drive-virtio-disk0,id=virtio-disk0 \
	-drive file=test.img,format=raw,if=none,id=drive-virtio-disk0

Links:
 - libtpms: https://github.com/stefanberger/libtpms/wiki
 - swtpm: https://github.com/stefanberger/swtpm/wiki

Changes:
 v3->v4:
  - addressed comments to v3
  - reworked suspend/resume support that requires extensions to backends

 v2->v3:
  - patch 1: a TPM 2 is identified by IBM,vtpm20 in the compatible node
  - patch 1: convert to tracing to display Tx and Rx buffers
  - added documentation patch
  - added patch to enable TPM device as part of pSeries

 v1->v2:
  - followed Cedric Le Goater's suggestions to patch 1
  - send appropriate CRQ error responses if DMA read or write fails
  - renamed tpm_spapr_got_payload to tpm_spapr_process_cmd and
    pass endianess-adjusted data pointer from CRQ to it

Regards,
    Stefan

Stefan Berger (8):
  tpm_spapr: Support TPM for ppc64 using CRQ based interface
  tpm_backend: Implement check whether tpm backend is suspended
  tpm_emulator: Implement callback for whether we are suspended
  tpm_passthrough: Implement callback for whether we are suspended
  tpm: Return bool from tpm_backend_finish_sync
  tpm_spapr: Support suspend and resume
  hw/ppc/Kconfig: Enable TPM_SPAPR as part of PSERIES config
  docs: tpm: Add example command line for ppc64 and tpm-spapr

 backends/tpm.c               |  13 +-
 docs/specs/tpm.txt           |  20 +-
 hw/ppc/Kconfig               |   1 +
 hw/tpm/Kconfig               |   6 +
 hw/tpm/Makefile.objs         |   1 +
 hw/tpm/tpm_emulator.c        |  12 +
 hw/tpm/tpm_passthrough.c     |   6 +
 hw/tpm/tpm_spapr.c           | 460 +++++++++++++++++++++++++++++++++++
 hw/tpm/trace-events          |  14 ++
 include/sysemu/tpm.h         |   3 +
 include/sysemu/tpm_backend.h |  16 +-
 qapi/tpm.json                |   6 +-
 12 files changed, 552 insertions(+), 6 deletions(-)
 create mode 100644 hw/tpm/tpm_spapr.c

-- 
2.21.0

Implement the check whether the emulator backend is suspended.

Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>

diff --git a/hw/tpm/tpm_emulator.c b/hw/tpm/tpm_emulator.c
index 22f9113432..7be7d3a91b 100644
--- a/hw/tpm/tpm_emulator.c
+++ b/hw/tpm/tpm_emulator.c
@@ -80,6 +80,8 @@ typedef struct TPMEmulator {
     unsigned int established_flag_cached:1;
 
     TPMBlobBuffers state_blobs;
+
+    bool is_suspended;
 } TPMEmulator;
 
 struct tpm_error {
@@ -486,6 +488,13 @@ static size_t tpm_emulator_get_buffer_size(TPMBackend *tb)
     return actual_size;
 }
 
+static bool tpm_emulator_is_suspended(TPMBackend *tb)
+{
+    TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
+
+    return tpm_emu->is_suspended;
+}
+
 static int tpm_emulator_block_migration(TPMEmulator *tpm_emu)
 {
     Error *err = NULL;
@@ -846,6 +855,8 @@ static int tpm_emulator_pre_save(void *opaque)
     TPMBackend *tb = opaque;
     TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
 
+    tpm_emu->is_suspended = true;
+
     trace_tpm_emulator_pre_save();
 
     tpm_backend_finish_sync(tb);
@@ -975,6 +986,7 @@ static void tpm_emulator_class_init(ObjectClass *klass, void *data)
     tbc->get_tpm_version = tpm_emulator_get_tpm_version;
     tbc->get_buffer_size = tpm_emulator_get_buffer_size;
     tbc->get_tpm_options = tpm_emulator_get_tpm_options;
+    tbc->is_suspended = tpm_emulator_is_suspended;
 
     tbc->handle_request = tpm_emulator_handle_request;
 }
-- 
2.21.0

On 12/12/19 1:07 PM, Stefan Berger wrote:
> Implement the check whether the emulator backend is suspended.
>
> Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
>
> diff --git a/hw/tpm/tpm_emulator.c b/hw/tpm/tpm_emulator.c
> index 22f9113432..7be7d3a91b 100644
> --- a/hw/tpm/tpm_emulator.c
> +++ b/hw/tpm/tpm_emulator.c
> @@ -80,6 +80,8 @@ typedef struct TPMEmulator {
>       unsigned int established_flag_cached:1;
>   
>       TPMBlobBuffers state_blobs;
> +
> +    bool is_suspended;
>   } TPMEmulator;
>   
>   struct tpm_error {
> @@ -486,6 +488,13 @@ static size_t tpm_emulator_get_buffer_size(TPMBackend *tb)
>       return actual_size;
>   }
>   
> +static bool tpm_emulator_is_suspended(TPMBackend *tb)
> +{
> +    TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
> +
> +    return tpm_emu->is_suspended;
> +}
> +
>   static int tpm_emulator_block_migration(TPMEmulator *tpm_emu)
>   {
>       Error *err = NULL;
> @@ -846,6 +855,8 @@ static int tpm_emulator_pre_save(void *opaque)
>       TPMBackend *tb = opaque;
>       TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
>   
> +    tpm_emu->is_suspended = true;

This is the most critical part here. It must be true when we receive a 
response in the tpm_spapr_request_completed(). The problem is that what 
tpm_backend_finish_sync() does is not specific to this backend but more 
a global operation that another device could run as well -- none seem to 
do this today. So the point is that there could be a race here. This 
flag should really be set in '.pre_pre_save,' so before any other device 
could poll. Better would be calling a global function that indicates 
whether device suspension has started. In this case we could do away 
with this and just call that function from the spapr device.

On 12/12/19 1:33 PM, Stefan Berger wrote:
> On 12/12/19 1:07 PM, Stefan Berger wrote:
>> Implement the check whether the emulator backend is suspended.
>>
>> Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
>>
>> diff --git a/hw/tpm/tpm_emulator.c b/hw/tpm/tpm_emulator.c
>> index 22f9113432..7be7d3a91b 100644
>> --- a/hw/tpm/tpm_emulator.c
>> +++ b/hw/tpm/tpm_emulator.c
>> @@ -80,6 +80,8 @@ typedef struct TPMEmulator {
>>       unsigned int established_flag_cached:1;
>>         TPMBlobBuffers state_blobs;
>> +
>> +    bool is_suspended;
>>   } TPMEmulator;
>>     struct tpm_error {
>> @@ -486,6 +488,13 @@ static size_t 
>> tpm_emulator_get_buffer_size(TPMBackend *tb)
>>       return actual_size;
>>   }
>>   +static bool tpm_emulator_is_suspended(TPMBackend *tb)
>> +{
>> +    TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
>> +
>> +    return tpm_emu->is_suspended;
>> +}
>> +
>>   static int tpm_emulator_block_migration(TPMEmulator *tpm_emu)
>>   {
>>       Error *err = NULL;
>> @@ -846,6 +855,8 @@ static int tpm_emulator_pre_save(void *opaque)
>>       TPMBackend *tb = opaque;
>>       TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
>>   +    tpm_emu->is_suspended = true;
>
> This is the most critical part here. It must be true when we receive a 
> response in the tpm_spapr_request_completed(). The problem is that 
> what tpm_backend_finish_sync() does is not specific to this backend 
> but more a global operation that another device could run as well -- 
> none seem to do this today. So the point is that there could be a race 
> here. This flag should really be set in '.pre_pre_save,' so before any 
> other device could poll. Better would be calling a global function 
> that indicates whether device suspension has started. In this case we 
> could do away with this and just call that function from the spapr 
> device.


runstate_check(RUN_STATE_FINISH_MIGRATE) seems to be what we need here...



>
>
>

Implement the callback for whether the passthrough backend is
suspended. We always respond with false.

Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>

diff --git a/hw/tpm/tpm_passthrough.c b/hw/tpm/tpm_passthrough.c
index f67244b5d4..b759c7d30c 100644
--- a/hw/tpm/tpm_passthrough.c
+++ b/hw/tpm/tpm_passthrough.c
@@ -203,6 +203,11 @@ static size_t tpm_passthrough_get_buffer_size(TPMBackend *tb)
     return tpm_pt->tpm_buffersize;
 }
 
+static bool tpm_passthrough_is_suspended(TPMBackend *tb)
+{
+    return false;
+}
+
 /*
  * Unless path or file descriptor set has been provided by user,
  * determine the sysfs cancel file following kernel documentation
@@ -386,6 +391,7 @@ static void tpm_passthrough_class_init(ObjectClass *klass, void *data)
     tbc->get_buffer_size = tpm_passthrough_get_buffer_size;
     tbc->get_tpm_options = tpm_passthrough_get_tpm_options;
     tbc->handle_request = tpm_passthrough_handle_request;
+    tbc->is_suspended = tpm_passthrough_is_suspended;
 }
 
 static const TypeInfo tpm_passthrough_info = {
-- 
2.21.0

Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>

diff --git a/hw/ppc/Kconfig b/hw/ppc/Kconfig
index f927ec9c74..b5b3519158 100644
--- a/hw/ppc/Kconfig
+++ b/hw/ppc/Kconfig
@@ -10,6 +10,7 @@ config PSERIES
     select XICS_SPAPR
     select XIVE_SPAPR
     select MSI_NONBROKEN
+    select TPM_SPAPR
 
 config SPAPR_RNG
     bool
-- 
2.21.0

Add an example to the TPM docs for how to add a TPM SPAPR
device model to a QEMU VM emulating a pSeries machine.

Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>

diff --git a/docs/specs/tpm.txt b/docs/specs/tpm.txt
index 9c8cca042d..9c3e67d8a7 100644
--- a/docs/specs/tpm.txt
+++ b/docs/specs/tpm.txt
@@ -34,6 +34,12 @@ The CRB interface makes a memory mapped IO region in the area 0xfed40000 -
 QEMU files related to TPM CRB interface:
  - hw/tpm/tpm_crb.c
 
+
+pSeries (ppc64) machines offer a tpm-spapr device model.
+
+QEMU files related to the SPAPR interface:
+ - hw/tpm/tpm_spapr.c
+
 = fw_cfg interface =
 
 The bios/firmware may read the "etc/tpm/config" fw_cfg entry for
@@ -281,7 +287,7 @@ swtpm socket --tpmstate dir=/tmp/mytpm1 \
   --log level=20
 
 Command line to start QEMU with the TPM emulator device communicating with
-the swtpm:
+the swtpm (x86):
 
 qemu-system-x86_64 -display sdl -accel kvm \
   -m 1024 -boot d -bios bios-256k.bin -boot menu=on \
@@ -289,6 +295,18 @@ qemu-system-x86_64 -display sdl -accel kvm \
   -tpmdev emulator,id=tpm0,chardev=chrtpm \
   -device tpm-tis,tpmdev=tpm0 test.img
 
+In case a pSeries machine is emulated, use the following command line:
+
+qemu-system-ppc64 -display sdl -machine pseries,accel=kvm \
+  -m 1024 -bios slof.bin -boot menu=on \
+  -nodefaults -device VGA -device pci-ohci -device usb-kbd \
+  -chardev socket,id=chrtpm,path=/tmp/mytpm1/swtpm-sock \
+  -tpmdev emulator,id=tpm0,chardev=chrtpm \
+  -device tpm-spapr,tpmdev=tpm0 \
+  -device spapr-vscsi,id=scsi0,reg=0x00002000 \
+  -device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x3,drive=drive-virtio-disk0,id=virtio-disk0 \
+  -drive file=test.img,format=raw,if=none,id=drive-virtio-disk0
+
 
 In case SeaBIOS is used as firmware, it should show the TPM menu item
 after entering the menu with 'ESC'.
-- 
2.21.0