tpm: factor out tpm 1.x pm suspend flow into tpm1-cmd.c (c82a330c) · Commits · 戴 / test

drivers/char/tpm/tpm-interface.c

+5 −50

Original line number	Diff line number	Diff line
		@@ -585,15 +585,6 @@ int tpm_send(struct tpm_chip chip, void cmd, size_t buflen)
		}
		EXPORT_SYMBOL_GPL(tpm_send);

		#define TPM_ORD_SAVESTATE 152
		#define SAVESTATE_RESULT_SIZE 10

		static const struct tpm_input_header savestate_header = {
		.tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
		.length = cpu_to_be32(10),
		.ordinal = cpu_to_be32(TPM_ORD_SAVESTATE)
		};

		/*
		* We are about to suspend. Save the TPM state
		* so that it can be restored.
		@@ -601,54 +592,18 @@ static const struct tpm_input_header savestate_header = {
		int tpm_pm_suspend(struct device *dev)
		{
		struct tpm_chip *chip = dev_get_drvdata(dev);
		struct tpm_cmd_t cmd;
		int rc, try;

		u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
		int rc = 0;

		if (chip == NULL)
		if (!chip)
		return -ENODEV;

		if (chip->flags & TPM_CHIP_FLAG_ALWAYS_POWERED)
		return 0;

		if (chip->flags & TPM_CHIP_FLAG_TPM2) {
		if (chip->flags & TPM_CHIP_FLAG_TPM2)
		tpm2_shutdown(chip, TPM2_SU_STATE);
		return 0;
		}

		/* for buggy tpm, flush pcrs with extend to selected dummy */
		if (tpm_suspend_pcr)
		rc = tpm1_pcr_extend(chip, tpm_suspend_pcr, dummy_hash,
		"extending dummy pcr before suspend");

		/* now do the actual savestate */
		for (try = 0; try < TPM_RETRY; try++) {
		cmd.header.in = savestate_header;
		rc = tpm_transmit_cmd(chip, NULL, &cmd, SAVESTATE_RESULT_SIZE,
		0, 0, NULL);

		/*
		* If the TPM indicates that it is too busy to respond to
		* this command then retry before giving up. It can take
		* several seconds for this TPM to be ready.
		*
		* This can happen if the TPM has already been sent the
		* SaveState command before the driver has loaded. TCG 1.2
		* specification states that any communication after SaveState
		* may cause the TPM to invalidate previously saved state.
		*/
		if (rc != TPM_WARN_RETRY)
		break;
		tpm_msleep(TPM_TIMEOUT_RETRY);
		}

		if (rc)
		dev_err(&chip->dev,
		"Error (%d) sending savestate before suspend\n", rc);
		else if (try > 0)
		dev_warn(&chip->dev, "TPM savestate took %dms\n",
		try * TPM_TIMEOUT_RETRY);
		else
		rc = tpm1_pm_suspend(chip, tpm_suspend_pcr);

		return rc;
		}

drivers/char/tpm/tpm.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -542,6 +542,8 @@ ssize_t tpm_transmit_cmd(struct tpm_chip chip, struct tpm_space space,
		const char *desc);
		int tpm_startup(struct tpm_chip *chip);
		int tpm_get_timeouts(struct tpm_chip *);

		int tpm1_pm_suspend(struct tpm_chip *chip, int tpm_suspend_pcr);
		int tpm1_auto_startup(struct tpm_chip *chip);
		int tpm1_do_selftest(struct tpm_chip *chip);
		int tpm1_get_timeouts(struct tpm_chip *chip);

drivers/char/tpm/tpm1-cmd.c

+61 −0

Original line number	Diff line number	Diff line
		@@ -666,3 +666,64 @@ out:
		rc = -ENODEV;
		return rc;
		}

		#define TPM_ORD_SAVESTATE 152
		#define SAVESTATE_RESULT_SIZE 10
		static const struct tpm_input_header savestate_header = {
		.tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
		.length = cpu_to_be32(10),
		.ordinal = cpu_to_be32(TPM_ORD_SAVESTATE)
		};

		/**
		* tpm1_pm_suspend() - pm suspend handler
		* @chip: TPM chip to use.
		* @tpm_suspend_pcr: flush pcr for buggy TPM chips.
		*
		* The functions saves the TPM state to be restored on resume.
		*
		* Return:
		* * 0 on success,
		* * < 0 on error.
		*/
		int tpm1_pm_suspend(struct tpm_chip *chip, int tpm_suspend_pcr)
		{
		u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
		struct tpm_cmd_t cmd;
		int rc, try;

		/* for buggy tpm, flush pcrs with extend to selected dummy */
		if (tpm_suspend_pcr)
		rc = tpm1_pcr_extend(chip, tpm_suspend_pcr, dummy_hash,
		"extending dummy pcr before suspend");

		/* now do the actual savestate */
		for (try = 0; try < TPM_RETRY; try++) {
		cmd.header.in = savestate_header;
		rc = tpm_transmit_cmd(chip, NULL, &cmd, SAVESTATE_RESULT_SIZE,
		0, 0, NULL);

		/*
		* If the TPM indicates that it is too busy to respond to
		* this command then retry before giving up. It can take
		* several seconds for this TPM to be ready.
		*
		* This can happen if the TPM has already been sent the
		* SaveState command before the driver has loaded. TCG 1.2
		* specification states that any communication after SaveState
		* may cause the TPM to invalidate previously saved state.
		*/
		if (rc != TPM_WARN_RETRY)
		break;
		tpm_msleep(TPM_TIMEOUT_RETRY);
		}

		if (rc)
		dev_err(&chip->dev, "Error (%d) sending savestate before suspend\n",
		rc);
		else if (try > 0)
		dev_warn(&chip->dev, "TPM savestate took %dms\n",
		try * TPM_TIMEOUT_RETRY);

		return rc;
		}

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