Request and relinquish locality for the driver use in order to be a better citizen in a multi locality environment like TXT.
Signed-off-by: Jarkko Sakkinen <[email protected]> --- drivers/char/tpm/tpm_crb.c | 73 ++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 64 insertions(+), 9 deletions(-) diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c index 853bd7b..96f661a 100644 --- a/drivers/char/tpm/tpm_crb.c +++ b/drivers/char/tpm/tpm_crb.c @@ -34,6 +34,15 @@ enum crb_defaults { CRB_ACPI_START_INDEX = 1, }; +enum crb_loc_ctrl { + CRB_LOC_CTRL_REQUEST_ACCESS = BIT(0), + CRB_LOC_CTRL_RELINQUISH = BIT(1), +}; + +enum crb_loc_state { + CRB_LOC_STATE_LOC_ASSIGNED = BIT(1), +}; + enum crb_ctrl_req { CRB_CTRL_REQ_CMD_READY = BIT(0), CRB_CTRL_REQ_GO_IDLE = BIT(1), @@ -165,13 +174,42 @@ static int __maybe_unused crb_cmd_ready(struct device *dev, CRB_CTRL_REQ_CMD_READY /* mask */, 0, /* value */ TPM2_TIMEOUT_C)) { - dev_warn(dev, "cmdReady timed out\n"); + dev_warn(dev, "TPM_CRB_CTRL_REQ_x.cmdReady timed out\n"); + return -ETIME; + } + + return 0; +} + +static int crb_request_locality(struct tpm_chip *chip) +{ + struct crb_priv *priv = dev_get_drvdata(&chip->dev); + + if (!priv->regs_h) + return 0; + + iowrite32(CRB_LOC_CTRL_REQUEST_ACCESS, &priv->regs_h->loc_ctrl); + if (!crb_wait_for_reg_32(&priv->regs_h->loc_state, + CRB_LOC_STATE_LOC_ASSIGNED, /* mask */ + CRB_LOC_STATE_LOC_ASSIGNED, /* value */ + TPM2_TIMEOUT_C)) { + dev_warn(&chip->dev, "TPM_LOC_STATE_x.requestAccess timed out\n"); return -ETIME; } return 0; } +static void crb_relinquish_locality(struct tpm_chip *chip) +{ + struct crb_priv *priv = dev_get_drvdata(&chip->dev); + + if (!priv->regs_h) + return; + + iowrite32(CRB_LOC_CTRL_RELINQUISH, &priv->regs_h->loc_ctrl); +} + static u8 crb_status(struct tpm_chip *chip) { struct crb_priv *priv = dev_get_drvdata(&chip->dev); @@ -188,23 +226,33 @@ static int crb_recv(struct tpm_chip *chip, u8 *buf, size_t count) { struct crb_priv *priv = dev_get_drvdata(&chip->dev); unsigned int expected; + int rc; /* sanity check */ if (count < 6) return -EIO; - if (ioread32(&priv->regs_t->ctrl_sts) & CRB_CTRL_STS_ERROR) - return -EIO; + rc = crb_request_locality(chip); + if (rc) + return rc; + + if (ioread32(&priv->regs_t->ctrl_sts) & CRB_CTRL_STS_ERROR) { + rc = -EIO; + goto out; + } memcpy_fromio(buf, priv->rsp, 6); expected = be32_to_cpup((__be32 *) &buf[2]); - - if (expected > count) - return -EIO; + if (expected > count) { + rc = -EIO; + goto out; + } memcpy_fromio(&buf[6], &priv->rsp[6], expected - 6); - return expected; +out: + crb_relinquish_locality(chip); + return rc ? rc : expected; } static int crb_do_acpi_start(struct tpm_chip *chip) @@ -227,7 +275,11 @@ static int crb_do_acpi_start(struct tpm_chip *chip) static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len) { struct crb_priv *priv = dev_get_drvdata(&chip->dev); - int rc = 0; + int rc; + + rc = crb_request_locality(chip); + if (rc) + return rc; /* Zero the cancel register so that the next command will not get * canceled. @@ -237,7 +289,8 @@ static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len) if (len > priv->cmd_size) { dev_err(&chip->dev, "invalid command count value %zd %d\n", len, priv->cmd_size); - return -E2BIG; + rc = -E2BIG; + goto out; } memcpy_toio(priv->cmd, buf, len); @@ -251,6 +304,8 @@ static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len) if (priv->flags & CRB_FL_ACPI_START) rc = crb_do_acpi_start(chip); +out: + crb_relinquish_locality(chip); return rc; } -- 2.9.3 ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ tpmdd-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/tpmdd-devel
