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Revert "drivers/i2c/tpm: Split cr50 driver from main driver"

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This reverts commit c565f99107.
This commit is contained in:
Duncan Laurie
2016-09-19 19:21:02 -07:00
parent 1de4f9549b
commit 9b8ebfb96c
4 changed files with 237 additions and 503 deletions
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242
src/drivers/i2c/tpm/tpm.c
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@@ -45,6 +45,7 @@
#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
@@ -57,16 +58,19 @@
/* 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",
};
@@ -107,6 +111,7 @@ 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++) {
@@ -469,6 +474,211 @@ 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)
@@ -482,8 +692,8 @@ 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;
tpm_dev->sleep_long = SLEEP_DURATION_LONG;
tpm_dev->sleep_short = SLEEP_DURATION_SAFE;
tpm_dev->sleep_long = SLEEP_DURATION_SAFE * 2;
/*
* Probe TPM. Check if the TPM_ACCESS register's ValidSts bit is set(1)
@@ -496,7 +706,7 @@ int tpm_vendor_probe(unsigned bus, uint32_t addr)
sw_run_duration = stopwatch_duration_msecs(&sw);
break;
}
udelay(SLEEP_DURATION);
udelay(SLEEP_DURATION_SAFE);
} while (!stopwatch_expired(&sw));
printk(BIOS_INFO,
@@ -526,8 +736,10 @@ 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;
tpm_dev->sleep_short = SLEEP_DURATION;
tpm_dev->sleep_long = SLEEP_DURATION_LONG;
/* Use conservative values to read chip id */
tpm_dev->sleep_short = SLEEP_DURATION_SAFE;
tpm_dev->sleep_long = SLEEP_DURATION_SAFE * 2;
memset(&chip->vendor, 0, sizeof(struct tpm_vendor_specific));
chip->is_open = 1;
@@ -535,10 +747,6 @@ 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;
@@ -554,11 +762,27 @@ 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);