From 8e54caf407b98efa05409e1fee0e5381abd2b088 Mon Sep 17 00:00:00 2001 From: Jason Gunthorpe Date: Wed, 21 May 2014 18:26:44 -0600 Subject: tpm: Provide a generic means to override the chip returned timeouts 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: [PHuewe: without this fix these 'broken' Atmel TPMs won't function on older kernels] Signed-off-by: "Berg, Christopher" Signed-off-by: Jason Gunthorpe Signed-off-by: Peter Huewe --- drivers/char/tpm/tpm-interface.c | 62 ++++++++++++++++++++++++++-------------- 1 file changed, 41 insertions(+), 21 deletions(-) (limited to 'drivers/char/tpm/tpm-interface.c') diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index bef6cceffc3a..6af17002a115 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -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; -- cgit v1.2.3