Messages in this thread |  | | Subject | Re: [PATCH 3/3] tpm: ibmvtpm: Add support for TPM 2 | From | Stefan Berger <> | Date | Thu, 13 Feb 2020 13:20:12 -0500 |
| |
On 2/13/20 12:53 PM, Nayna wrote: > > On 2/4/20 8:27 AM, Stefan Berger wrote: >> From: Stefan Berger <stefanb@linux.ibm.com> >> >> Support TPM 2 in the IBM vTPM driver. The hypervisor tells us what >> version of TPM is connected through the vio_device_id. >> >> In case a TPM 2 is found, we set the TPM_OPS_AUTO_STARTUP flag to >> have properly initialize the TPM and driver. >> >> Signed-off-by: Stefan Berger <stefanb@linux.ibm.com> >> --- >> drivers/char/tpm/tpm_ibmvtpm.c | 8 +++++++- >> 1 file changed, 7 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/char/tpm/tpm_ibmvtpm.c >> b/drivers/char/tpm/tpm_ibmvtpm.c >> index eee566eddb35..d479d64a65aa 100644 >> --- a/drivers/char/tpm/tpm_ibmvtpm.c >> +++ b/drivers/char/tpm/tpm_ibmvtpm.c >> @@ -29,6 +29,7 @@ static const char tpm_ibmvtpm_driver_name[] = >> "tpm_ibmvtpm"; >> >> static const struct vio_device_id tpm_ibmvtpm_device_table[] = { >> { "IBM,vtpm", "IBM,vtpm"}, >> + { "IBM,vtpm", "IBM,vtpm20"}, >> { "", "" } >> }; >> MODULE_DEVICE_TABLE(vio, tpm_ibmvtpm_device_table); >> @@ -443,7 +444,7 @@ static bool tpm_ibmvtpm_req_canceled(struct >> tpm_chip *chip, u8 status) >> return (status == 0); >> } >> >> -static const struct tpm_class_ops tpm_ibmvtpm = { >> +static struct tpm_class_ops tpm_ibmvtpm = { >> .recv = tpm_ibmvtpm_recv, >> .send = tpm_ibmvtpm_send, >> .cancel = tpm_ibmvtpm_cancel, >> @@ -672,6 +673,11 @@ static int tpm_ibmvtpm_probe(struct vio_dev >> *vio_dev, >> if (rc) >> goto init_irq_cleanup; >> >> + if (!strcmp(id->compat, "IBM,vtpm20")) { >> + chip->flags |= TPM_CHIP_FLAG_TPM2; >> + tpm_ibmvtpm.flags = TPM_OPS_AUTO_STARTUP; > > TPM_OPS_AUTO_STARTUP flag isn't set for vTPM 1.2. What is different in > case of vTPM 2.0 ?
I don't want side effects for the TPM 1.2 case here, so I am only modifying the flag for the case where the new TPM 2 is being used. Here's the code where it shows the effect.
int tpm_auto_startup(struct tpm_chip *chip) { int rc;
if (!(chip->ops->flags & TPM_OPS_AUTO_STARTUP)) return 0;
if (chip->flags & TPM_CHIP_FLAG_TPM2) rc = tpm2_auto_startup(chip); else rc = tpm1_auto_startup(chip);
return rc; }
In the TPM 2 case we then get timeouts, do the TPM self test, send TPM2_STARTUP if necessary and get attributes of the TPM 2 command from the device. All necessary to start it up.
https://elixir.bootlin.com/linux/latest/source/drivers/char/tpm/tpm2-cmd.c#L719
Does this answer your question ?
Stefan
> > Thanks & Regards, > > - Nayna >
|  |