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SubjectRe: [PATCH] tpm/tpm_crb: Use start method value from ACPI table directly
On Wed, Sep 13, 2017 at 03:33:51PM -0500, anjiandi@codeaurora.org wrote:
> On 2017-09-06 07:39, Jarkko Sakkinen wrote:
> > On Fri, Aug 25, 2017 at 06:28:55PM -0500, Jiandi An wrote:
> > > This patch gets rid of dealing with intermediate flag for start method
> > > and use start method value from ACPI table directly.
> > >
> > > For ARM64, the locality is handled by Trust Zone in FW. The layout
> > > does not have crb_regs_head. It is hitting the following line.
> > > dev_warn(dev, FW_BUG "Bad ACPI memory layout");
> > >
> > > Current code excludes CRB_FL_ACPI_START for this check. Now since
> > > ARM64 support for TPM CRB is added, CRB_FL_CRB_SMC_START should also
> > > be
> > > excluded from this check.
> > >
> > > For goIdle and cmdReady where code was excluding CRB_FL_ACPI_START
> > > only
> > > (do nothing for ACPI start method), CRB_FL_CRB_SMC_START was also
> > > excluded as ARM64 SMC start method does not have TPM_CRB_CTRL_REQ.
> > >
> > > However with special PPT workaround requiring CRB_FL_CRB_START to be
> > > set in addition to CRB_FL_ACPI_START and the addition flag of SMC
> > > start method CRB_FL_CRB_SMC_START, the code has become difficult to
> > > maintain and undrestand. It is better to make code deal with start
> > > method value from ACPI table directly.
> > >
> > > Signed-off-by: Jiandi An <anjiandi@codeaurora.org>
> > > ---
> > > drivers/char/tpm/tpm_crb.c | 59
> > > +++++++++++++++++++++++-----------------------
> > > 1 file changed, 29 insertions(+), 30 deletions(-)
> > >
> > > diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c
> > > index 8f0a98d..7b3c2a8 100644
> > > --- a/drivers/char/tpm/tpm_crb.c
> > > +++ b/drivers/char/tpm/tpm_crb.c
> > > @@ -92,14 +92,9 @@ enum crb_status {
> > > CRB_DRV_STS_COMPLETE = BIT(0),
> > > };
> > >
> > > -enum crb_flags {
> > > - CRB_FL_ACPI_START = BIT(0),
> > > - CRB_FL_CRB_START = BIT(1),
> > > - CRB_FL_CRB_SMC_START = BIT(2),
> > > -};
> > > -
> > > struct crb_priv {
> > > - unsigned int flags;
> > > + u32 sm;
> > > + const char *hid;
> > > void __iomem *iobase;
> > > struct crb_regs_head __iomem *regs_h;
> > > struct crb_regs_tail __iomem *regs_t;
> > > @@ -128,14 +123,16 @@ struct tpm2_crb_smc {
> > > * Anyhow, we do not wait here as a consequent CMD_READY request
> > > * will be handled correctly even if idle was not completed.
> > > *
> > > - * The function does nothing for devices with ACPI-start method.
> > > + * The function does nothing for devices with ACPI-start method
> > > + * or SMC-start method.
> > > *
> > > * Return: 0 always
> > > */
> > > static int __maybe_unused crb_go_idle(struct device *dev, struct
> > > crb_priv *priv)
> > > {
> > > - if ((priv->flags & CRB_FL_ACPI_START) ||
> > > - (priv->flags & CRB_FL_CRB_SMC_START))
> > > + if ((priv->sm == ACPI_TPM2_START_METHOD) ||
> > > + (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD) ||
> > > + (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC))
> > > return 0;
> > >
> > > iowrite32(CRB_CTRL_REQ_GO_IDLE, &priv->regs_t->ctrl_req);
> > > @@ -174,14 +171,16 @@ static bool crb_wait_for_reg_32(u32 __iomem
> > > *reg, u32 mask, u32 value,
> > > * The device should respond within TIMEOUT_C.
> > > *
> > > * The function does nothing for devices with ACPI-start method
> > > + * or SMC-start method.
> > > *
> > > * Return: 0 on success -ETIME on timeout;
> > > */
> > > static int __maybe_unused crb_cmd_ready(struct device *dev,
> > > struct crb_priv *priv)
> > > {
> > > - if ((priv->flags & CRB_FL_ACPI_START) ||
> > > - (priv->flags & CRB_FL_CRB_SMC_START))
> > > + if ((priv->sm == ACPI_TPM2_START_METHOD) ||
> > > + (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD) ||
> > > + (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC))
> > > return 0;
> > >
> > > iowrite32(CRB_CTRL_REQ_CMD_READY, &priv->regs_t->ctrl_req);
> > > @@ -325,13 +324,20 @@ static int crb_send(struct tpm_chip *chip, u8
> > > *buf, size_t len)
> > > /* Make sure that cmd is populated before issuing start. */
> > > wmb();
> > >
> > > - if (priv->flags & CRB_FL_CRB_START)
> > > + /* The reason for the extra quirk is that the PTT in 4th Gen Core
> > > CPUs
> > > + * report only ACPI start but in practice seems to require both
> > > + * CRB start, hence invoking CRB start method if hid == MSFT0101.
> > > + */
> > > + if ((priv->sm == ACPI_TPM2_COMMAND_BUFFER) ||
> > > + (priv->sm == ACPI_TPM2_MEMORY_MAPPED) ||
> > > + (!strcmp(priv->hid, "MSFT0101")))
> > > iowrite32(CRB_START_INVOKE, &priv->regs_t->ctrl_start);
> > >
> > > - if (priv->flags & CRB_FL_ACPI_START)
> > > + if ((priv->sm == ACPI_TPM2_START_METHOD) ||
> > > + (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD))
> > > rc = crb_do_acpi_start(chip);
> > >
> > > - if (priv->flags & CRB_FL_CRB_SMC_START) {
> > > + if (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC) {
> > > iowrite32(CRB_START_INVOKE, &priv->regs_t->ctrl_start);
> > > rc = tpm_crb_smc_start(&chip->dev, priv->smc_func_id);
> > > }
> > > @@ -345,7 +351,9 @@ static void crb_cancel(struct tpm_chip *chip)
> > >
> > > iowrite32(CRB_CANCEL_INVOKE, &priv->regs_t->ctrl_cancel);
> > >
> > > - if ((priv->flags & CRB_FL_ACPI_START) && crb_do_acpi_start(chip))
> > > + if (((priv->sm == ACPI_TPM2_START_METHOD) ||
> > > + (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD)) &&
> > > + crb_do_acpi_start(chip))
> > > dev_err(&chip->dev, "ACPI Start failed\n");
> > > }
> > >
> > > @@ -458,7 +466,8 @@ static int crb_map_io(struct acpi_device
> > > *device, struct crb_priv *priv,
> > > * the control area, as one nice sane region except for some older
> > > * stuff that puts the control area outside the ACPI IO region.
> > > */
> > > - if (!(priv->flags & CRB_FL_ACPI_START)) {
> > > + if ((priv->sm == ACPI_TPM2_COMMAND_BUFFER) ||
> > > + (priv->sm == ACPI_TPM2_MEMORY_MAPPED)) {
> > > if (buf->control_address == io_res.start +
> > > sizeof(*priv->regs_h))
> > > priv->regs_h = priv->iobase;
> > > @@ -552,18 +561,6 @@ static int crb_acpi_add(struct acpi_device
> > > *device)
> > > if (!priv)
> > > return -ENOMEM;
> > >
> > > - /* The reason for the extra quirk is that the PTT in 4th Gen Core
> > > CPUs
> > > - * report only ACPI start but in practice seems to require both
> > > - * ACPI start and CRB start.
> > > - */
> > > - if (sm == ACPI_TPM2_COMMAND_BUFFER || sm ==
> > > ACPI_TPM2_MEMORY_MAPPED ||
> > > - !strcmp(acpi_device_hid(device), "MSFT0101"))
> > > - priv->flags |= CRB_FL_CRB_START;
> > > -
> > > - if (sm == ACPI_TPM2_START_METHOD ||
> > > - sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD)
> > > - priv->flags |= CRB_FL_ACPI_START;
> > > -
> > > if (sm == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC) {
> > > if (buf->header.length < (sizeof(*buf) + sizeof(*crb_smc))) {
> > > dev_err(dev,
> > > @@ -574,9 +571,11 @@ static int crb_acpi_add(struct acpi_device
> > > *device)
> > > }
> > > crb_smc = ACPI_ADD_PTR(struct tpm2_crb_smc, buf, sizeof(*buf));
> > > priv->smc_func_id = crb_smc->smc_func_id;
> > > - priv->flags |= CRB_FL_CRB_SMC_START;
> > > }
> > >
> > > + priv->sm = sm;
> > > + priv->hid = acpi_device_hid(device);
> > > +
> > > rc = crb_map_io(device, priv, buf);
> > > if (rc)
> > > return rc;
> > > --
> > > Jiandi An
> > > Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm
> > > Technologies, Inc.
> > > Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a
> > > Linux Foundation Collaborative Project.
> >
> > Tested-by: Jarkko Sakkinen <jarkko.sakkine@linux.intel.com>
> >
> > I run smoke test suite [1]:
> >
> > $ python -m unittest -v tpm2_smoke
> > test_seal_with_auth (tpm2_smoke.SmokeTest) ... ok
> > test_seal_with_policy (tpm2_smoke.SmokeTest) ... ok
> > test_seal_with_too_long_auth (tpm2_smoke.SmokeTest) ... ok
> > test_unseal_with_wrong_auth (tpm2_smoke.SmokeTest) ... ok
> > test_unseal_with_wrong_policy (tpm2_smoke.SmokeTest) ... ok
> > test_flush_context (tpm2_smoke.SpaceTest) ... ok
> > test_get_handles (tpm2_smoke.SpaceTest) ... ok
> > test_make_two_spaces (tpm2_smoke.SpaceTest) ... ok
> >
> > ----------------------------------------------------------------------
> > Ran 8 tests in 25.816s
> >
> > OK
> >
> > This doesn't verify that things work on ARM64 because for that I do not
> > pose a test platform. However, since tpm_crb is not in wide use yet on
> > that platform I do not think it matters. And the code changes do not
> > have huge potential to cause collateral damage even if they were broken
> > on that platform.
> >
> > [1] https://github.com/jsakkine-intel/tpm2-scripts
> >
> > /Jarkko
>
> Hi Jarkko,
>
> I tested on ARM64 on Qualcomm QDF2400 platform. Will this be pulled to
> linux-next or your tree for 4.14 merge window?
> Thanks.

Nope. I do feature pull request around rc5/rc6 of previous release.

/Jarkko

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