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tpm: Provide a generic means to override the chip returned timeouts

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Some Atmel TPMs provide completely wrong timeouts from their
TPM_CAP_PROP_TIS_TIMEOUT query. This patch detects that and returns
new correct values via a DID/VID table in the TIS driver.

Tested on ARM using an AT97SC3204T FW version 37.16

Cc: <stable@vger.kernel.org>
[PHuewe: without this fix these 'broken' Atmel TPMs won't function on
older kernels]
Signed-off-by: "Berg, Christopher" <Christopher.Berg@atmel.com>
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>

Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
This commit is contained in:
Jason Gunthorpe 2014-05-21 18:26:44 -06:00 committed by Peter Huewe
parent 3e14d83ef9
commit 8e54caf407
3 changed files with 75 additions and 21 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

62
drivers/char/tpm/tpm-interface.c
View file

@ -491,11 +491,10 @@ static int tpm_startup(struct tpm_chip *chip, __be16 startup_type)
int tpm_get_timeouts(struct tpm_chip *chip)
{
struct tpm_cmd_t tpm_cmd;
struct timeout_t *timeout_cap;
unsigned long new_timeout[4];
unsigned long old_timeout[4];
struct duration_t *duration_cap;
ssize_t rc;
u32 timeout;
unsigned int scale = 1;
tpm_cmd.header.in = tpm_getcap_header;
tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
@ -529,25 +528,46 @@ int tpm_get_timeouts(struct tpm_chip *chip)
!= sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
return -EINVAL;
timeout_cap = &tpm_cmd.params.getcap_out.cap.timeout;
/* Don't overwrite default if value is 0 */
timeout = be32_to_cpu(timeout_cap->a);
if (timeout && timeout < 1000) {
/* timeouts in msec rather usec */
scale = 1000;
chip->vendor.timeout_adjusted = true;
old_timeout[0] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.a);
old_timeout[1] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.b);
old_timeout[2] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.c);
old_timeout[3] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.d);
memcpy(new_timeout, old_timeout, sizeof(new_timeout));
/*
* Provide ability for vendor overrides of timeout values in case
* of misreporting.
*/
if (chip->ops->update_timeouts != NULL)
chip->vendor.timeout_adjusted =
chip->ops->update_timeouts(chip, new_timeout);
if (!chip->vendor.timeout_adjusted) {
/* Don't overwrite default if value is 0 */
if (new_timeout[0] != 0 && new_timeout[0] < 1000) {
int i;
/* timeouts in msec rather usec */
for (i = 0; i != ARRAY_SIZE(new_timeout); i++)
new_timeout[i] *= 1000;
chip->vendor.timeout_adjusted = true;
}
}
if (timeout)
chip->vendor.timeout_a = usecs_to_jiffies(timeout * scale);
timeout = be32_to_cpu(timeout_cap->b);
if (timeout)
chip->vendor.timeout_b = usecs_to_jiffies(timeout * scale);
timeout = be32_to_cpu(timeout_cap->c);
if (timeout)
chip->vendor.timeout_c = usecs_to_jiffies(timeout * scale);
timeout = be32_to_cpu(timeout_cap->d);
if (timeout)
chip->vendor.timeout_d = usecs_to_jiffies(timeout * scale);
/* Report adjusted timeouts */
if (chip->vendor.timeout_adjusted) {
dev_info(chip->dev,
HW_ERR "Adjusting reported timeouts: A %lu->%luus B %lu->%luus C %lu->%luus D %lu->%luus\n",
old_timeout[0], new_timeout[0],
old_timeout[1], new_timeout[1],
old_timeout[2], new_timeout[2],
old_timeout[3], new_timeout[3]);
}
chip->vendor.timeout_a = usecs_to_jiffies(new_timeout[0]);
chip->vendor.timeout_b = usecs_to_jiffies(new_timeout[1]);
chip->vendor.timeout_c = usecs_to_jiffies(new_timeout[2]);
chip->vendor.timeout_d = usecs_to_jiffies(new_timeout[3]);
duration:
tpm_cmd.header.in = tpm_getcap_header;

31
drivers/char/tpm/tpm_tis.c
View file

@ -373,6 +373,36 @@ static int tpm_tis_send(struct tpm_chip *chip, u8 *buf, size_t len)
return rc;
}
struct tis_vendor_timeout_override {
u32 did_vid;
unsigned long timeout_us[4];
};
static const struct tis_vendor_timeout_override vendor_timeout_overrides[] = {
/* Atmel 3204 */
{ 0x32041114, { (TIS_SHORT_TIMEOUT*1000), (TIS_LONG_TIMEOUT*1000),
(TIS_SHORT_TIMEOUT*1000), (TIS_SHORT_TIMEOUT*1000) } },
};
static bool tpm_tis_update_timeouts(struct tpm_chip *chip,
unsigned long *timeout_cap)
{
int i;
u32 did_vid;
did_vid = ioread32(chip->vendor.iobase + TPM_DID_VID(0));
for (i = 0; i != ARRAY_SIZE(vendor_timeout_overrides); i++) {
if (vendor_timeout_overrides[i].did_vid != did_vid)
continue;
memcpy(timeout_cap, vendor_timeout_overrides[i].timeout_us,
sizeof(vendor_timeout_overrides[i].timeout_us));
return true;
}
return false;
}
/*
* Early probing for iTPM with STS_DATA_EXPECT flaw.
* Try sending command without itpm flag set and if that
@ -437,6 +467,7 @@ static const struct tpm_class_ops tpm_tis = {
.recv = tpm_tis_recv,
.send = tpm_tis_send,
.cancel = tpm_tis_ready,
.update_timeouts = tpm_tis_update_timeouts,
.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,

3
include/linux/tpm.h
View file

@ -39,6 +39,9 @@ struct tpm_class_ops {
int (*send) (struct tpm_chip *chip, u8 *buf, size_t len);
void (*cancel) (struct tpm_chip *chip);
u8 (*status) (struct tpm_chip *chip);
bool (*update_timeouts)(struct tpm_chip *chip,
unsigned long *timeout_cap);
};
#if defined(CONFIG_TCG_TPM) || defined(CONFIG_TCG_TPM_MODULE)