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Diffstat (limited to 'src/drivers/i2c/tpm/tpm.c')
-rw-r--r--src/drivers/i2c/tpm/tpm.c242
1 files changed, 9 insertions, 233 deletions
diff --git a/src/drivers/i2c/tpm/tpm.c b/src/drivers/i2c/tpm/tpm.c
index 6b96774f60..55c25fefa4 100644
--- a/src/drivers/i2c/tpm/tpm.c
+++ b/src/drivers/i2c/tpm/tpm.c
@@ -45,7 +45,6 @@
#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 */
/* max. number of iterations after I2C NAK for 'long' commands
@@ -58,19 +57,16 @@
/* expected value for DIDVID register */
#define TPM_TIS_I2C_DID_VID_9635 0x000b15d1L
#define TPM_TIS_I2C_DID_VID_9645 0x001a15d1L
-#define TPM_TIS_I2C_DID_VID_CR50 0x00281ae0L
enum i2c_chip_type {
SLB9635,
SLB9645,
- CR50,
UNKNOWN,
};
static const char * const chip_name[] = {
[SLB9635] = "slb9635tt",
[SLB9645] = "slb9645tt",
- [CR50] = "cr50",
[UNKNOWN] = "unknown/fallback to slb9635",
};
@@ -111,7 +107,6 @@ static int iic_tpm_read(uint8_t addr, uint8_t *buffer, size_t len)
switch (tpm_dev->chip_type) {
case SLB9635:
- case CR50:
case UNKNOWN:
/* slb9635 protocol should work in both cases */
for (count = 0; count < MAX_COUNT; count++) {
@@ -474,211 +469,6 @@ out_err:
return -1;
}
-/*
- * cr50 is a TPM 2.0 capable device that requries special
- * handling for the I2C interface.
- *
- * - Timeouts need to be longer
- * - Must use the older SLB9635 style write+wait+read read protocol
- * - All 4 bytes of status register must be read at once
- * - Burst count max is 63 bytes, and burst count behaves
- * slightly differently than other I2C TPMs
- * - When reading from FIFO the full burstcnt must be read
- * instead of just reading header and determining the remainder
- */
-
-/* cr50 max burst count */
-#define CR50_MAX_BURSTCOUNT 63
-
-/* cr50 requires all 4 bytes of status register to be read */
-static uint8_t cr50_tis_i2c_status(struct tpm_chip *chip)
-{
- uint8_t buf[4];
- if (iic_tpm_read(TPM_STS(chip->vendor.locality),
- buf, sizeof(buf)) < 0) {
- printk(BIOS_ERR, "%s: Failed to read status\n", __func__);
- return 0;
- }
- return buf[0];
-}
-
-/* cr50 requires all 4 bytes of status register to be written */
-static void cr50_tis_i2c_ready(struct tpm_chip *chip)
-{
- uint8_t buf[4] = { TPM_STS_COMMAND_READY };
- iic_tpm_write_long(TPM_STS(chip->vendor.locality), buf, sizeof(buf));
-}
-
-/* cr50 uses bytes 3:2 of status register for burst count and
- * all 4 bytes must be read */
-static int cr50_wait_burst_status(struct tpm_chip *chip, uint8_t mask,
- size_t *burst, int *status)
-{
- uint8_t buf[4];
- struct stopwatch sw;
-
- stopwatch_init_msecs_expire(&sw, 2000);
-
- 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);
- continue;
- }
-
- *status = buf[0];
- *burst = read_le16(&buf[1]);
-
- /* Check if mask matches and burst is valid */
- if ((*status & mask) == mask &&
- *burst > 0 && *burst <= CR50_MAX_BURSTCOUNT)
- return 0;
-
- udelay(SLEEP_DURATION_SAFE);
- }
-
- printk(BIOS_ERR, "%s: Timeout reading burst and status\n", __func__);
- return -1;
-}
-
-static int cr50_tis_i2c_recv(struct tpm_chip *chip, uint8_t *buf,
- size_t buf_len)
-{
- size_t burstcnt, current, len, expected;
- uint8_t addr = TPM_DATA_FIFO(chip->vendor.locality);
- int status;
- int ret = -1;
-
- if (buf_len < TPM_HEADER_SIZE)
- goto out;
-
- if (cr50_wait_burst_status(chip, TPM_STS_VALID, &burstcnt, &status) < 0)
- goto out;
- if (!(status & TPM_STS_DATA_AVAIL)) {
- printk(BIOS_ERR, "%s: First chunk not available\n", __func__);
- goto out;
- }
-
- /* Read first chunk of burstcnt bytes */
- if (iic_tpm_read(addr, buf, burstcnt) != 0) {
- printk(BIOS_ERR, "%s: Read failed\n", __func__);
- goto out;
- }
-
- /* Determine expected data in the return buffer */
- expected = read_be32(buf + TPM_RSP_SIZE_BYTE);
- if (expected > buf_len) {
- printk(BIOS_ERR, "%s: Too much data: %zu > %zu\n",
- __func__, expected, buf_len);
- goto out;
- }
-
- /* Now read the rest of the data */
- current = burstcnt;
- while (current < expected) {
- /* Read updated burst count and check status */
- if (cr50_wait_burst_status(chip, TPM_STS_VALID,
- &burstcnt, &status) < 0)
- goto out;
- if (!(status & TPM_STS_DATA_AVAIL)) {
- printk(BIOS_ERR, "%s: Data not available\n", __func__);
- goto out;
- }
-
- len = min(burstcnt, expected - current);
- if (iic_tpm_read(addr, buf + current, len) != 0) {
- printk(BIOS_ERR, "%s: Read failed\n", __func__);
- goto out;
- }
-
- current += len;
- }
-
- /* Ensure TPM is done reading data */
- if (cr50_wait_burst_status(chip, TPM_STS_VALID, &burstcnt, &status) < 0)
- goto out;
- if (status & TPM_STS_DATA_AVAIL) {
- printk(BIOS_ERR, "%s: Data still available\n", __func__);
- goto out;
- }
-
- ret = current;
-
-out:
- return ret;
-}
-
-static int cr50_tis_i2c_send(struct tpm_chip *chip, uint8_t *buf, size_t len)
-{
- int status;
- size_t burstcnt, limit, sent = 0;
- uint8_t tpm_go[4] = { TPM_STS_GO };
- struct stopwatch sw;
-
- if (len > TPM_BUFSIZE)
- return -1;
-
- stopwatch_init_msecs_expire(&sw, 2000);
-
- /* Wait until TPM is ready for a command */
- while (!(cr50_tis_i2c_status(chip) & TPM_STS_COMMAND_READY)) {
- if (stopwatch_expired(&sw)) {
- printk(BIOS_ERR, "%s: Command ready timeout\n",
- __func__);
- return -1;
- }
-
- cr50_tis_i2c_ready(chip);
- udelay(SLEEP_DURATION_SAFE);
- }
-
- while (len > 0) {
- /* Read burst count and check status */
- if (cr50_wait_burst_status(chip, TPM_STS_VALID,
- &burstcnt, &status) < 0)
- goto out;
- if (sent > 0 && !(status & TPM_STS_DATA_EXPECT)) {
- printk(BIOS_ERR, "%s: Data not expected\n", __func__);
- goto out;
- }
-
- /* Use burstcnt - 1 to account for the address byte
- * that is inserted by iic_tpm_write() */
- limit = min(burstcnt - 1, len);
- if (iic_tpm_write(TPM_DATA_FIFO(chip->vendor.locality),
- &buf[sent], limit) != 0) {
- printk(BIOS_ERR, "%s: Write failed\n", __func__);
- goto out;
- }
-
- sent += limit;
- len -= limit;
- }
-
- /* Ensure TPM is not expecting more data */
- if (cr50_wait_burst_status(chip, TPM_STS_VALID, &burstcnt, &status) < 0)
- goto out;
- if (status & TPM_STS_DATA_EXPECT) {
- printk(BIOS_ERR, "%s: Data still expected\n", __func__);
- goto out;
- }
-
- /* Start the TPM command */
- if (iic_tpm_write(TPM_STS(chip->vendor.locality), tpm_go,
- sizeof(tpm_go)) < 0) {
- printk(BIOS_ERR, "%s: Start command failed\n", __func__);
- goto out;
- }
- return sent;
-
-out:
- /* Abort current transaction if still pending */
- if (cr50_tis_i2c_status(chip) & TPM_STS_COMMAND_READY)
- cr50_tis_i2c_ready(chip);
- return -1;
-}
-
/* Initialization of I2C TPM */
int tpm_vendor_probe(unsigned bus, uint32_t addr)
@@ -692,8 +482,8 @@ int tpm_vendor_probe(unsigned bus, uint32_t addr)
tpm_dev->chip_type = UNKNOWN;
tpm_dev->bus = bus;
tpm_dev->addr = addr;
- tpm_dev->sleep_short = SLEEP_DURATION_SAFE;
- tpm_dev->sleep_long = SLEEP_DURATION_SAFE * 2;
+ tpm_dev->sleep_short = SLEEP_DURATION;
+ tpm_dev->sleep_long = SLEEP_DURATION_LONG;
/*
* Probe TPM. Check if the TPM_ACCESS register's ValidSts bit is set(1)
@@ -706,7 +496,7 @@ int tpm_vendor_probe(unsigned bus, uint32_t addr)
sw_run_duration = stopwatch_duration_msecs(&sw);
break;
}
- udelay(SLEEP_DURATION_SAFE);
+ udelay(SLEEP_DURATION);
} while (!stopwatch_expired(&sw));
printk(BIOS_INFO,
@@ -736,10 +526,8 @@ int tpm_vendor_init(struct tpm_chip *chip, unsigned bus, uint32_t dev_addr)
tpm_dev->chip_type = UNKNOWN;
tpm_dev->bus = bus;
tpm_dev->addr = dev_addr;
-
- /* Use conservative values to read chip id */
- tpm_dev->sleep_short = SLEEP_DURATION_SAFE;
- tpm_dev->sleep_long = SLEEP_DURATION_SAFE * 2;
+ tpm_dev->sleep_short = SLEEP_DURATION;
+ tpm_dev->sleep_long = SLEEP_DURATION_LONG;
memset(&chip->vendor, 0, sizeof(struct tpm_vendor_specific));
chip->is_open = 1;
@@ -747,6 +535,10 @@ int tpm_vendor_init(struct tpm_chip *chip, unsigned bus, uint32_t dev_addr)
chip->vendor.req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID;
chip->vendor.req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID;
chip->vendor.req_canceled = TPM_STS_COMMAND_READY;
+ chip->vendor.status = &tpm_tis_i2c_status;
+ chip->vendor.recv = &tpm_tis_i2c_recv;
+ chip->vendor.send = &tpm_tis_i2c_send;
+ chip->vendor.cancel = &tpm_tis_i2c_ready;
/* Disable interrupts (not supported) */
chip->vendor.irq = 0;
@@ -762,27 +554,11 @@ int tpm_vendor_init(struct tpm_chip *chip, unsigned bus, uint32_t dev_addr)
tpm_dev->chip_type = SLB9645;
} else if (be32_to_cpu(vendor) == TPM_TIS_I2C_DID_VID_9635) {
tpm_dev->chip_type = SLB9635;
- } else if (vendor == TPM_TIS_I2C_DID_VID_CR50) {
- tpm_dev->chip_type = CR50;
} else {
printk(BIOS_DEBUG, "Vendor ID 0x%08x not recognized.\n", vendor);
goto out_err;
}
- if (tpm_dev->chip_type == CR50) {
- chip->vendor.status = &cr50_tis_i2c_status;
- chip->vendor.recv = &cr50_tis_i2c_recv;
- chip->vendor.send = &cr50_tis_i2c_send;
- chip->vendor.cancel = &cr50_tis_i2c_ready;
- } else {
- tpm_dev->sleep_short = SLEEP_DURATION;
- tpm_dev->sleep_long = SLEEP_DURATION_LONG;
- chip->vendor.status = &tpm_tis_i2c_status;
- chip->vendor.recv = &tpm_tis_i2c_recv;
- chip->vendor.send = &tpm_tis_i2c_send;
- chip->vendor.cancel = &tpm_tis_i2c_ready;
- }
-
printk(BIOS_DEBUG, "I2C TPM %u:%02x (chip type %s device-id 0x%X)\n",
tpm_dev->bus, tpm_dev->addr,
chip_name[tpm_dev->chip_type], vendor >> 16);