2019-09-02 14:29:13

by Jerry Snitselaar

[permalink] [raw]
Subject: [PATCH v4 3/3] tpm_tis: override durations for STM tpm with firmware 1.2.8.28

There was revealed a bug in the STM TPM chipset used in Dell R415s.
Bug is observed so far only on chipset firmware 1.2.8.28
(1.2 TPM, device-id 0x0, rev-id 78). After some number of
operations chipset hangs and stays in inconsistent state:

tpm_tis 00:09: Operation Timed out
tpm_tis 00:09: tpm_transmit: tpm_send: error -5

Durations returned by the chip are the same like on other
firmware revisions but apparently with specifically 1.2.8.28 fw
durations should be reset to 2 minutes to enable tpm chip work
properly. No working way of updating firmware was found.

This patch adds implementation of ->update_durations method
that matches only STM devices with specific firmware version.

Cc: Peter Huewe <[email protected]>
Cc: Jarkko Sakkinen <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Signed-off-by: Alexey Klimov <[email protected]>
Signed-off-by: Jerry Snitselaar <[email protected]>
Reviewed-by: Jarkko Sakkinen <[email protected]>
---
drivers/char/tpm/tpm_tis_core.c | 79 +++++++++++++++++++++++++++++++++
1 file changed, 79 insertions(+)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index c3181ea9f271..27c6ca031e23 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -506,6 +506,84 @@ static int tpm_tis_send(struct tpm_chip *chip, u8 *buf, size_t len)
return rc;
}

+struct tis_vendor_durations_override {
+ u32 did_vid;
+ struct tpm1_version version;
+ unsigned long durations[3];
+};
+
+static const struct tis_vendor_durations_override vendor_dur_overrides[] = {
+ /* STMicroelectronics 0x104a */
+ { 0x0000104a,
+ { 1, 2, 8, 28 },
+ { (2 * 60 * HZ), (2 * 60 * HZ), (2 * 60 * HZ) } },
+};
+
+static void tpm_tis_update_durations(struct tpm_chip *chip,
+ unsigned long *duration_cap)
+{
+ struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+ struct tpm1_version *version;
+ u32 did_vid;
+ int i, rc;
+ cap_t cap;
+
+ chip->duration_adjusted = false;
+
+ if (chip->ops->clk_enable != NULL)
+ chip->ops->clk_enable(chip, true);
+
+ rc = tpm_tis_read32(priv, TPM_DID_VID(0), &did_vid);
+ if (rc < 0) {
+ dev_warn(&chip->dev, "%s: failed to read did_vid. %d\n",
+ __func__, rc);
+ goto out;
+ }
+
+ /* Try to get a TPM version 1.2 or 1.1 TPM_CAP_VERSION_INFO */
+ rc = tpm1_getcap(chip, TPM_CAP_VERSION_1_2, &cap,
+ "attempting to determine the 1.2 version",
+ sizeof(cap.version2));
+ if (!rc) {
+ version = &cap.version2.version;
+ } else {
+ rc = tpm1_getcap(chip, TPM_CAP_VERSION_1_1, &cap,
+ "attempting to determine the 1.1 version",
+ sizeof(cap.version1));
+
+ if (rc)
+ goto out;
+
+ version = &cap.version1;
+ }
+
+ for (i = 0; i != ARRAY_SIZE(vendor_dur_overrides); i++) {
+ if (vendor_dur_overrides[i].did_vid != did_vid)
+ continue;
+
+ if ((version->major ==
+ vendor_dur_overrides[i].version.major) &&
+ (version->minor ==
+ vendor_dur_overrides[i].version.minor) &&
+ (version->rev_major ==
+ vendor_dur_overrides[i].version.rev_major) &&
+ (version->rev_minor ==
+ vendor_dur_overrides[i].version.rev_minor)) {
+
+ memcpy(duration_cap,
+ vendor_dur_overrides[i].durations,
+ sizeof(vendor_dur_overrides[i].durations));
+
+ chip->duration_adjusted = true;
+ goto out;
+ }
+ }
+
+out:
+ if (chip->ops->clk_enable != NULL)
+ chip->ops->clk_enable(chip, false);
+}
+
struct tis_vendor_timeout_override {
u32 did_vid;
unsigned long timeout_us[4];
@@ -842,6 +920,7 @@ static const struct tpm_class_ops tpm_tis = {
.send = tpm_tis_send,
.cancel = tpm_tis_ready,
.update_timeouts = tpm_tis_update_timeouts,
+ .update_durations = tpm_tis_update_durations,
.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,
--
2.21.0


2019-09-03 15:55:59

by Jarkko Sakkinen

[permalink] [raw]
Subject: Re: [PATCH v4 3/3] tpm_tis: override durations for STM tpm with firmware 1.2.8.28

On Mon, 2019-09-02 at 07:27 -0700, Jerry Snitselaar wrote:
> There was revealed a bug in the STM TPM chipset used in Dell R415s.
> Bug is observed so far only on chipset firmware 1.2.8.28
> (1.2 TPM, device-id 0x0, rev-id 78). After some number of
> operations chipset hangs and stays in inconsistent state:
>
> tpm_tis 00:09: Operation Timed out
> tpm_tis 00:09: tpm_transmit: tpm_send: error -5
>
> Durations returned by the chip are the same like on other
> firmware revisions but apparently with specifically 1.2.8.28 fw
> durations should be reset to 2 minutes to enable tpm chip work
> properly. No working way of updating firmware was found.
>
> This patch adds implementation of ->update_durations method
> that matches only STM devices with specific firmware version.
>
> Cc: Peter Huewe <[email protected]>
> Cc: Jarkko Sakkinen <[email protected]>
> Cc: Jason Gunthorpe <[email protected]>
> Signed-off-by: Alexey Klimov <[email protected]>
> Signed-off-by: Jerry Snitselaar <[email protected]>
> Reviewed-by: Jarkko Sakkinen <[email protected]>

Tested-by: Jarkko Sakkinen <[email protected]> (!update_durations path)

/Jarkko