diff options
Diffstat (limited to 'src/drivers/i2c/tpm/tpm.c')
-rw-r--r-- | src/drivers/i2c/tpm/tpm.c | 242 |
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); |