[PATCH v4 2/6] tpm, tpm_tis: Claim and release locality only once

From: Lino Sanfilippo
Date: Mon May 09 2022 - 04:26:44 EST


From: Lino Sanfilippo <l.sanfilippo@xxxxxxxxxx>

It is not necessary to claim and release the default locality for each TPM
command. Instead claim the locality once at driver startup and release it
at driver shutdown.

Signed-off-by: Lino Sanfilippo <l.sanfilippo@xxxxxxxxxx>
---
drivers/char/tpm/tpm_tis_core.c | 50 +++++++++------------------------
1 file changed, 13 insertions(+), 37 deletions(-)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index 52369ef39b03..46f504fb5084 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -638,9 +638,6 @@ static int probe_itpm(struct tpm_chip *chip)
if (vendor != TPM_VID_INTEL)
return 0;

- if (request_locality(chip, 0) != 0)
- return -EBUSY;
-
rc = tpm_tis_send_data(chip, cmd_getticks, len);
if (rc == 0)
goto out;
@@ -659,7 +656,6 @@ static int probe_itpm(struct tpm_chip *chip)

out:
tpm_tis_ready(chip);
- release_locality(chip, priv->locality);

return rc;
}
@@ -721,17 +717,11 @@ static int tpm_tis_gen_interrupt(struct tpm_chip *chip)
cap_t cap;
int ret;

- ret = request_locality(chip, 0);
- if (ret < 0)
- return ret;
-
if (chip->flags & TPM_CHIP_FLAG_TPM2)
ret = tpm2_get_tpm_pt(chip, 0x100, &cap2, desc);
else
ret = tpm1_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, desc, 0);

- release_locality(chip, 0);
-
return ret;
}

@@ -855,6 +845,8 @@ void tpm_tis_remove(struct tpm_chip *chip)

tpm_tis_write32(priv, reg, ~TPM_GLOBAL_INT_ENABLE & interrupt);

+ release_locality(chip, 0);
+
tpm_tis_clkrun_enable(chip, false);

if (priv->ilb_base_addr)
@@ -925,8 +917,6 @@ static const struct tpm_class_ops tpm_tis = {
.req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
.req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
.req_canceled = tpm_tis_req_canceled,
- .request_locality = request_locality,
- .relinquish_locality = release_locality,
.clk_enable = tpm_tis_clkrun_enable,
};

@@ -963,9 +953,15 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,

dev_set_drvdata(&chip->dev, priv);

+ rc = request_locality(chip, 0);
+ if (rc)
+ return rc;
+
rc = tpm_tis_read32(priv, TPM_DID_VID(0), &vendor);
- if (rc < 0)
+ if (rc < 0) {
+ release_locality(chip, 0);
return rc;
+ }

priv->manufacturer_id = vendor;

@@ -978,8 +974,10 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
if (is_bsw()) {
priv->ilb_base_addr = ioremap(INTEL_LEGACY_BLK_BASE_ADDR,
ILB_REMAP_SIZE);
- if (!priv->ilb_base_addr)
+ if (!priv->ilb_base_addr) {
+ release_locality(chip, 0);
return -ENOMEM;
+ }

clkrun_val = ioread32(priv->ilb_base_addr + LPC_CNTRL_OFFSET);
/* Check if CLKRUN# is already not enabled in the LPC bus */
@@ -1006,14 +1004,7 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
TPM_INTF_DATA_AVAIL_INT | TPM_INTF_STS_VALID_INT;
intmask &= ~TPM_GLOBAL_INT_ENABLE;

- rc = request_locality(chip, 0);
- if (rc < 0) {
- rc = -ENODEV;
- goto out_err;
- }
-
tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), intmask);
- release_locality(chip, 0);

rc = tpm_chip_start(chip);
if (rc)
@@ -1072,15 +1063,7 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
* to make sure it works. May as well use that command to set the
* proper timeouts for the driver.
*/
-
- rc = request_locality(chip, 0);
- if (rc < 0)
- goto out_err;
-
rc = tpm_get_timeouts(chip);
-
- release_locality(chip, 0);
-
if (rc) {
dev_err(dev, "Could not get TPM timeouts and durations\n");
rc = -ENODEV;
@@ -1169,16 +1152,9 @@ int tpm_tis_resume(struct device *dev)
* TPM 1.2 requires self-test on resume. This function actually returns
* an error code but for unknown reason it isn't handled.
*/
- if (!(chip->flags & TPM_CHIP_FLAG_TPM2)) {
- ret = request_locality(chip, 0);
- if (ret < 0)
- return ret;
-
+ if (!(chip->flags & TPM_CHIP_FLAG_TPM2))
tpm1_do_selftest(chip);

- release_locality(chip, 0);
- }
-
return 0;
}
EXPORT_SYMBOL_GPL(tpm_tis_resume);
--
2.36.0