drivers/i2c/tpm/cr50.c: Check if TPM was read
Under some conditions, cr50_i2c_read() can return without actually reading
the TPM, which will leave access uninitialized. Set an initial value for
access, and if TPM fails to respond in time check if at least TPM was read.
This way avoids printing an uninitialized value.
BUG=b:112253891
TEST=Build and boot grunt.
Change-Id: I5ec7a99396db32971dc8485b77158d735ab1d788
Signed-off-by: Richard Spiegel <richard.spiegel@silverbackltd.com>
Reviewed-on: https://review.coreboot.org/27995
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martinroth@google.com>
Reviewed-by: Marshall Dawson <marshalldawson3rd@gmail.com>
diff --git a/src/drivers/i2c/tpm/cr50.c b/src/drivers/i2c/tpm/cr50.c
index 3c2f5bd..14a84de 100644
--- a/src/drivers/i2c/tpm/cr50.c
+++ b/src/drivers/i2c/tpm/cr50.c
@@ -181,6 +181,7 @@
static int process_reset(struct tpm_chip *chip)
{
struct stopwatch sw;
+ int rv = 0;
uint8_t access;
/*
@@ -193,7 +194,6 @@
*/
stopwatch_init_msecs_expire(&sw, CR50_TIMEOUT_INIT_MS);
do {
- int rv;
const uint8_t mask =
TPM_ACCESS_VALID | TPM_ACCESS_ACTIVE_LOCALITY;
@@ -214,9 +214,12 @@
return 0;
} while (!stopwatch_expired(&sw));
- printk(BIOS_ERR,
- "TPM failed to reset after %ld ms, status: %#x\n",
- stopwatch_duration_msecs(&sw), access);
+ if (rv)
+ printk(BIOS_ERR, "Failed to read TPM\n");
+ else
+ printk(BIOS_ERR,
+ "TPM failed to reset after %ld ms, status: %#x\n",
+ stopwatch_duration_msecs(&sw), access);
return -1;
}