drivers/i2c/tpm/cr50: Clean up timeouts
Use two different timeouts in the driver. The 2ms timeout is needed
to be safe for cr50 to cover the extended timeout that is seen with
some commands. The other at 2 seconds which is a TPM spec timeout.
BUG=chrome-os-partner:53336
Change-Id: I77fdd7ea646b8b2fef449f07e3a08bcce174fe8b
Signed-off-by: Duncan Laurie <dlaurie@chromium.org>
diff --git a/src/drivers/i2c/tpm/cr50.c b/src/drivers/i2c/tpm/cr50.c
index 1190262..6627851 100644
--- a/src/drivers/i2c/tpm/cr50.c
+++ b/src/drivers/i2c/tpm/cr50.c
@@ -42,12 +42,9 @@
#include "tpm.h"
-#define SLEEP_DURATION 60 /* in usec */
-#define SLEEP_DURATION_LONG 210 /* in usec */
-#define SLEEP_DURATION_SAFE 750 /* in usec */
-#define SLEEP_DURATION_PROBE_MS 1000 /* in msec */
-
#define CR50_MAX_BUFSIZE 63
+#define CR50_TIMEOUT_LONG_MS 2000 /* Long timeout while waiting for TPM */
+#define CR50_TIMEOUT_SHORT_MS 2 /* Short timeout during transactions */
#define CR50_DID_VID 0x00281ae0L
struct tpm_inf_dev {
@@ -85,7 +82,7 @@
}
/* Wait for TPM to be ready with response data */
- udelay(SLEEP_DURATION_SAFE);
+ mdelay(CR50_TIMEOUT_SHORT_MS);
/* Read response data from the TPM */
if (i2c_read_raw(tpm_dev->bus, tpm_dev->addr, buffer, len)) {
@@ -129,7 +126,7 @@
}
/* Wait for TPM to be ready */
- udelay(SLEEP_DURATION_SAFE);
+ mdelay(CR50_TIMEOUT_SHORT_MS);
return 0;
}
@@ -201,6 +198,7 @@
{
uint8_t buf[4] = { TPM_STS_COMMAND_READY };
iic_tpm_write(TPM_STS(chip->vendor.locality), buf, sizeof(buf));
+ mdelay(CR50_TIMEOUT_SHORT_MS);
}
/* cr50 uses bytes 3:2 of status register for burst count and
@@ -211,13 +209,13 @@
uint8_t buf[4];
struct stopwatch sw;
- stopwatch_init_msecs_expire(&sw, 2000);
+ stopwatch_init_msecs_expire(&sw, CR50_TIMEOUT_LONG_MS);
while (!stopwatch_expired(&sw)) {
if (iic_tpm_read(TPM_STS(chip->vendor.locality),
buf, sizeof(buf)) != 0) {
printk(BIOS_WARNING, "%s: Read failed\n", __func__);
- udelay(SLEEP_DURATION_SAFE);
+ mdelay(CR50_TIMEOUT_SHORT_MS);
continue;
}
@@ -229,7 +227,7 @@
*burst > 0 && *burst <= CR50_MAX_BUFSIZE)
return 0;
- udelay(SLEEP_DURATION_SAFE);
+ mdelay(CR50_TIMEOUT_SHORT_MS);
}
printk(BIOS_ERR, "%s: Timeout reading burst and status\n", __func__);
@@ -310,7 +308,7 @@
uint8_t tpm_go[4] = { TPM_STS_GO };
struct stopwatch sw;
- stopwatch_init_msecs_expire(&sw, 2000);
+ stopwatch_init_msecs_expire(&sw, CR50_TIMEOUT_LONG_MS);
/* Wait until TPM is ready for a command */
while (!(cr50_tis_i2c_status(chip) & TPM_STS_COMMAND_READY)) {
@@ -321,7 +319,6 @@
}
cr50_tis_i2c_ready(chip);
- udelay(SLEEP_DURATION_SAFE);
}
while (len > 0) {
@@ -388,7 +385,7 @@
struct stopwatch sw;
uint8_t buf = 0;
int ret;
- long sw_run_duration = SLEEP_DURATION_PROBE_MS;
+ long sw_run_duration = CR50_TIMEOUT_LONG_MS;
tpm_dev->bus = bus;
tpm_dev->addr = addr;
@@ -401,7 +398,7 @@
sw_run_duration = stopwatch_duration_msecs(&sw);
break;
}
- udelay(SLEEP_DURATION_SAFE);
+ mdelay(CR50_TIMEOUT_SHORT_MS);
} while (!stopwatch_expired(&sw));
printk(BIOS_INFO,