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authorDuncan Laurie <dlaurie@chromium.org>2016-09-19 17:09:01 -0700
committerPatrick Georgi <pgeorgi@google.com>2016-09-21 10:45:09 +0200
commitd3920e71d61e76d4e8ae30bd8466d22b7bf3432c (patch)
tree38f2e859e7c783f335b19032c365278a748f6a1f /src/drivers/i2c
parent510cb6a1444d4b85dd6d374280322e35044e16d3 (diff)
downloadcoreboot-d3920e71d61e76d4e8ae30bd8466d22b7bf3432c.tar.xz
drivers/i2c/tpm/cr50: Clean up locality functions
Clean up the mask and timeout handling in the locality functions that were copied from the original driver. BUG=chrome-os-partner:53336 Change-Id: Ifdcb3be0036b2c02bfbd1bcd326e9519d3726ee0 Signed-off-by: Duncan Laurie <dlaurie@chromium.org> Reviewed-on: https://review.coreboot.org/16667 Tested-by: build bot (Jenkins) Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Diffstat (limited to 'src/drivers/i2c')
-rw-r--r--src/drivers/i2c/tpm/cr50.c39
1 files changed, 20 insertions, 19 deletions
diff --git a/src/drivers/i2c/tpm/cr50.c b/src/drivers/i2c/tpm/cr50.c
index fbc3ece09b..a3ff7814de 100644
--- a/src/drivers/i2c/tpm/cr50.c
+++ b/src/drivers/i2c/tpm/cr50.c
@@ -137,13 +137,13 @@ static int cr50_i2c_write(struct tpm_chip *chip,
static int check_locality(struct tpm_chip *chip, int loc)
{
+ uint8_t mask = TPM_ACCESS_VALID | TPM_ACCESS_ACTIVE_LOCALITY;
uint8_t buf;
if (cr50_i2c_read(chip, TPM_ACCESS(loc), &buf, 1) < 0)
return -1;
- if ((buf & (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) ==
- (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) {
+ if ((buf & mask) == mask) {
chip->vendor.locality = loc;
return loc;
}
@@ -151,40 +151,41 @@ static int check_locality(struct tpm_chip *chip, int loc)
return -1;
}
-static void release_locality(struct tpm_chip *chip, int loc, int force)
+static void release_locality(struct tpm_chip *chip, int force)
{
+ uint8_t mask = TPM_ACCESS_VALID | TPM_ACCESS_REQUEST_PENDING;
+ uint8_t addr = TPM_ACCESS(chip->vendor.locality);
uint8_t buf;
- if (cr50_i2c_read(chip, TPM_ACCESS(loc), &buf, 1) < 0)
+ if (cr50_i2c_read(chip, addr, &buf, 1) < 0)
return;
- if (force || (buf & (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID)) ==
- (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID)) {
+ if (force || (buf & mask) == mask) {
buf = TPM_ACCESS_ACTIVE_LOCALITY;
- cr50_i2c_write(chip, TPM_ACCESS(loc), &buf, 1);
+ cr50_i2c_write(chip, addr, &buf, 1);
}
+
+ chip->vendor.locality = 0;
}
static int request_locality(struct tpm_chip *chip, int loc)
{
uint8_t buf = TPM_ACCESS_REQUEST_USE;
+ struct stopwatch sw;
if (check_locality(chip, loc) >= 0)
- return loc; /* we already have the locality */
+ return loc;
if (cr50_i2c_write(chip, TPM_ACCESS(loc), &buf, 1) < 0)
return -1;
- /* wait for burstcount */
- int timeout = 2 * 1000; /* 2s timeout */
- while (timeout) {
- if (check_locality(chip, loc) >= 0)
- return loc;
- mdelay(TPM_TIMEOUT);
- timeout--;
+ stopwatch_init_msecs_expire(&sw, CR50_TIMEOUT_LONG_MS);
+ while (check_locality(chip, loc) < 0) {
+ if (stopwatch_expired(&sw))
+ return -1;
+ mdelay(CR50_TIMEOUT_SHORT_MS);
}
-
- return -1;
+ return loc;
}
/* cr50 requires all 4 bytes of status register to be read */
@@ -458,11 +459,11 @@ int tpm_vendor_init(struct tpm_chip *chip, unsigned bus, uint32_t dev_addr)
return 0;
out_err:
- release_locality(chip, 0, 1);
+ release_locality(chip, 1);
return -1;
}
void tpm_vendor_cleanup(struct tpm_chip *chip)
{
- release_locality(chip, chip->vendor.locality, 1);
+ release_locality(chip, 1);
}