From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jarkko Sakkinen Subject: Re: [PATCH] tpm/tpm_crb: Use start method value from ACPI table directly Date: Wed, 6 Sep 2017 15:39:02 +0300 Message-ID: <20170906123902.ovirukgahfvjldxa@linux.intel.com> References: <1503703735-2332-1-git-send-email-anjiandi@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1503703735-2332-1-git-send-email-anjiandi@codeaurora.org> Sender: linux-kernel-owner@vger.kernel.org To: Jiandi An Cc: peterhuewe@gmx.de, tpmdd@selhorst.net, jgunthorpe@obsidianresearch.com, tpmdd-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org List-Id: tpmdd-devel@lists.sourceforge.net 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 > --- > 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 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