diff options
Diffstat (limited to 'src/drivers/pc80')
| -rw-r--r-- | src/drivers/pc80/tpm/tis.c | 36 |
1 files changed, 19 insertions, 17 deletions
diff --git a/src/drivers/pc80/tpm/tis.c b/src/drivers/pc80/tpm/tis.c index 2b29acfaa9..c209e5a39e 100644 --- a/src/drivers/pc80/tpm/tis.c +++ b/src/drivers/pc80/tpm/tis.c @@ -22,6 +22,7 @@ #include <security/tpm/tis.h> #include <device/pnp.h> #include <drivers/tpm/tpm_ppi.h> +#include <timer.h> #include "chip.h" #define PREFIX "lpc_tpm: " @@ -84,7 +85,7 @@ #define TPM_DRIVER_ERR (~0) /* 1 second is plenty for anything TPM does.*/ -#define MAX_DELAY_US (1000 * 1000) +#define MAX_DELAY_US USECS_PER_SEC /* * Structures defined below allow creating descriptions of TPM vendor/device @@ -238,7 +239,7 @@ static inline u32 tpm_read_int_polarity(int locality) /* * tis_wait_sts() * - * Wait for at least a second for a status to change its state to match the + * Wait for at most a second for a status to change its state to match the * expected state. Normally the transition happens within microseconds. * * @locality - locality @@ -249,14 +250,15 @@ static inline u32 tpm_read_int_polarity(int locality) */ static int tis_wait_sts(int locality, u8 mask, u8 expected) { - u32 time_us = MAX_DELAY_US; - while (time_us > 0) { + struct stopwatch sw; + + stopwatch_init_usecs_expire(&sw, MAX_DELAY_US); + do { u8 value = tpm_read_status(locality); if ((value & mask) == expected) return 0; - udelay(1); /* 1 us */ - time_us--; - } + udelay(1); + } while (!stopwatch_expired(&sw)); return TPM_TIMEOUT_ERR; } @@ -291,7 +293,7 @@ static inline int tis_expect_data(int locality) /* * tis_wait_access() * - * Wait for at least a second for a access to change its state to match the + * Wait for at most a second for a access to change its state to match the * expected state. Normally the transition happens within microseconds. * * @locality - locality @@ -302,14 +304,15 @@ static inline int tis_expect_data(int locality) */ static int tis_wait_access(int locality, u8 mask, u8 expected) { - u32 time_us = MAX_DELAY_US; - while (time_us > 0) { + struct stopwatch sw; + + stopwatch_init_usecs_expire(&sw, MAX_DELAY_US); + do { u8 value = tpm_read_access(locality); if ((value & mask) == expected) return 0; - udelay(1); /* 1 us */ - time_us--; - } + udelay(1); + } while (!stopwatch_expired(&sw)); return TPM_TIMEOUT_ERR; } @@ -440,7 +443,6 @@ static u32 tis_senddata(const u8 *const data, u32 len) { u32 offset = 0; u16 burst = 0; - u32 max_cycles = 0; u8 locality = 0; if (tis_wait_ready(locality)) { @@ -452,10 +454,12 @@ static u32 tis_senddata(const u8 *const data, u32 len) while (1) { unsigned int count; + struct stopwatch sw; /* Wait till the device is ready to accept more data. */ + stopwatch_init_usecs_expire(&sw, MAX_DELAY_US); while (!burst) { - if (max_cycles++ == MAX_DELAY_US) { + if (stopwatch_expired(&sw)) { printf("%s:%d failed to feed %d bytes of %d\n", __FILE__, __LINE__, len - offset, len); return TPM_DRIVER_ERR; @@ -464,8 +468,6 @@ static u32 tis_senddata(const u8 *const data, u32 len) burst = tpm_read_burst_count(locality); } - max_cycles = 0; - /* * Calculate number of bytes the TPM is ready to accept in one * shot. |