diff options
Diffstat (limited to 'src/drivers/i2c/tpm')
-rw-r--r-- | src/drivers/i2c/tpm/cr50.c | 93 |
1 files changed, 48 insertions, 45 deletions
diff --git a/src/drivers/i2c/tpm/cr50.c b/src/drivers/i2c/tpm/cr50.c index 37f0881980..a3ff7814de 100644 --- a/src/drivers/i2c/tpm/cr50.c +++ b/src/drivers/i2c/tpm/cr50.c @@ -189,7 +189,7 @@ static int request_locality(struct tpm_chip *chip, int loc) } /* cr50 requires all 4 bytes of status register to be read */ -static uint8_t cr50_i2c_tis_status(struct tpm_chip *chip) +static uint8_t cr50_tis_i2c_status(struct tpm_chip *chip) { uint8_t buf[4]; if (cr50_i2c_read(chip, TPM_STS(chip->vendor.locality), @@ -201,7 +201,7 @@ static uint8_t cr50_i2c_tis_status(struct tpm_chip *chip) } /* cr50 requires all 4 bytes of status register to be written */ -static void cr50_i2c_tis_ready(struct tpm_chip *chip) +static void cr50_tis_i2c_ready(struct tpm_chip *chip) { uint8_t buf[4] = { TPM_STS_COMMAND_READY }; cr50_i2c_write(chip, TPM_STS(chip->vendor.locality), buf, sizeof(buf)); @@ -210,7 +210,7 @@ static void cr50_i2c_tis_ready(struct tpm_chip *chip) /* cr50 uses bytes 3:2 of status register for burst count and * all 4 bytes must be read */ -static int cr50_i2c_wait_burststs(struct tpm_chip *chip, uint8_t mask, +static int cr50_wait_burst_status(struct tpm_chip *chip, uint8_t mask, size_t *burst, int *status) { uint8_t buf[4]; @@ -240,26 +240,28 @@ static int cr50_i2c_wait_burststs(struct tpm_chip *chip, uint8_t mask, return -1; } -static int cr50_i2c_tis_recv(struct tpm_chip *chip, uint8_t *buf, +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); - uint8_t mask = TPM_STS_VALID | TPM_STS_DATA_AVAIL; int status; + int ret = -1; if (buf_len < TPM_HEADER_SIZE) - goto out_err; + goto out; - if (cr50_i2c_wait_burststs(chip, mask, &burstcnt, &status) < 0) { + 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_err; + goto out; } /* Read first chunk of burstcnt bytes */ if (cr50_i2c_read(chip, addr, buf, burstcnt) != 0) { printk(BIOS_ERR, "%s: Read failed\n", __func__); - goto out_err; + goto out; } /* Determine expected data in the return buffer */ @@ -267,43 +269,45 @@ static int cr50_i2c_tis_recv(struct tpm_chip *chip, uint8_t *buf, if (expected > buf_len) { printk(BIOS_ERR, "%s: Too much data: %zu > %zu\n", __func__, expected, buf_len); - goto out_err; + goto out; } /* Now read the rest of the data */ current = burstcnt; while (current < expected) { /* Read updated burst count and check status */ - if (cr50_i2c_wait_burststs(chip, mask, &burstcnt, &status) < 0) - goto out_err; + 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 (cr50_i2c_read(chip, addr, buf + current, len) != 0) { printk(BIOS_ERR, "%s: Read failed\n", __func__); - goto out_err; + goto out; } current += len; } /* Ensure TPM is done reading data */ - if (cr50_i2c_wait_burststs(chip, TPM_STS_VALID, &burstcnt, &status) < 0) - goto out_err; + 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_err; + goto out; } - return current; + ret = current; -out_err: - /* Abort current transaction if still pending */ - if (cr50_i2c_tis_status(chip) & TPM_STS_COMMAND_READY) - cr50_i2c_tis_ready(chip); - return -1; +out: + return ret; } -static int cr50_i2c_tis_send(struct tpm_chip *chip, uint8_t *buf, size_t len) +static int cr50_tis_i2c_send(struct tpm_chip *chip, uint8_t *buf, size_t len) { int status; size_t burstcnt, limit, sent = 0; @@ -313,26 +317,25 @@ static int cr50_i2c_tis_send(struct tpm_chip *chip, uint8_t *buf, size_t len) stopwatch_init_msecs_expire(&sw, CR50_TIMEOUT_LONG_MS); /* Wait until TPM is ready for a command */ - while (!(cr50_i2c_tis_status(chip) & TPM_STS_COMMAND_READY)) { + 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_i2c_tis_ready(chip); + cr50_tis_i2c_ready(chip); } while (len > 0) { - uint8_t mask = TPM_STS_VALID; - - /* Wait for data if this is not the first chunk */ - if (sent > 0) - mask |= TPM_STS_DATA_EXPECT; - /* Read burst count and check status */ - if (cr50_i2c_wait_burststs(chip, mask, &burstcnt, &status) < 0) - goto out_err; + 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 cr50_i2c_write() */ @@ -340,7 +343,7 @@ static int cr50_i2c_tis_send(struct tpm_chip *chip, uint8_t *buf, size_t len) if (cr50_i2c_write(chip, TPM_DATA_FIFO(chip->vendor.locality), &buf[sent], limit) != 0) { printk(BIOS_ERR, "%s: Write failed\n", __func__); - goto out_err; + goto out; } sent += limit; @@ -348,25 +351,25 @@ static int cr50_i2c_tis_send(struct tpm_chip *chip, uint8_t *buf, size_t len) } /* Ensure TPM is not expecting more data */ - if (cr50_i2c_wait_burststs(chip, TPM_STS_VALID, &burstcnt, &status) < 0) - goto out_err; + 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_err; + goto out; } /* Start the TPM command */ if (cr50_i2c_write(chip, TPM_STS(chip->vendor.locality), tpm_go, sizeof(tpm_go)) < 0) { printk(BIOS_ERR, "%s: Start command failed\n", __func__); - goto out_err; + goto out; } return sent; -out_err: +out: /* Abort current transaction if still pending */ - if (cr50_i2c_tis_status(chip) & TPM_STS_COMMAND_READY) - cr50_i2c_tis_ready(chip); + if (cr50_tis_i2c_status(chip) & TPM_STS_COMMAND_READY) + cr50_tis_i2c_ready(chip); return -1; } @@ -376,10 +379,10 @@ static void cr50_vendor_init(struct tpm_chip *chip) 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 = &cr50_i2c_tis_status; - chip->vendor.recv = &cr50_i2c_tis_recv; - chip->vendor.send = &cr50_i2c_tis_send; - chip->vendor.cancel = &cr50_i2c_tis_ready; + 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; } int tpm_vendor_probe(unsigned bus, uint32_t addr) |