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_tis.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) (limited to 'drivers/char/tpm/tpm_tis.c') diff --git a/drivers/char/tpm/tpm_tis.c b/drivers/char/tpm/tpm_tis.c index a9ed2270c25d..2c46734b266d 100644 --- a/drivers/char/tpm/tpm_tis.c +++ b/drivers/char/tpm/tpm_tis.c @@ -373,6 +373,36 @@ out_err: 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, -- cgit v1.2.3