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authorDuncan Laurie <dlaurie@chromium.org>2016-09-19 19:21:02 -0700
committerDuncan Laurie <dlaurie@chromium.org>2016-09-19 19:21:02 -0700
commit9b8ebfb96cf0937add6ad8478887d8932450e255 (patch)
tree1a59fff6307fe36dd239d8452818904385ea5496 /src/drivers/i2c/tpm/cr50.c
parent1de4f9549b8cb290451843dc9d2274887d4f3b22 (diff)
Revert "drivers/i2c/tpm: Split cr50 driver from main driver"
This reverts commit c565f9910707b91fcc7a27bab28806e558bb474d.
Diffstat (limited to 'src/drivers/i2c/tpm/cr50.c')
-rw-r--r--src/drivers/i2c/tpm/cr50.c466
1 files changed, 0 insertions, 466 deletions
diff --git a/src/drivers/i2c/tpm/cr50.c b/src/drivers/i2c/tpm/cr50.c
deleted file mode 100644
index 419ac1e68f..0000000000
--- a/src/drivers/i2c/tpm/cr50.c
+++ /dev/null
@@ -1,466 +0,0 @@
-/*
- * Copyright 2016 Google Inc.
- *
- * Based on Linux Kernel TPM driver by
- * Peter Huewe <peter.huewe@infineon.com>
- * Copyright (C) 2011 Infineon Technologies
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation, version 2 of the
- * License.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- */
-
-/*
- * cr50 is a TPM 2.0 capable device that requries special
- * handling for the I2C interface.
- *
- * - Use an interrupt for transaction status instead of hardcoded delays
- * - Must use write+wait+read read protocol
- * - All 4 bytes of status register must be read/written 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
- */
-
-#include <arch/early_variables.h>
-#include <commonlib/endian.h>
-#include <stdint.h>
-#include <string.h>
-#include <types.h>
-#include <delay.h>
-#include <console/console.h>
-#include <device/i2c.h>
-#include <endian.h>
-#include <timer.h>
-#include "tpm.h"
-
-#define CR50_MAX_BURSTCOUNT 63
-
-#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 */
-
-#define CR50_DID_VID 0x00281ae0L
-
-struct tpm_inf_dev {
- int bus;
- unsigned int addr;
- uint8_t buf[TPM_BUFSIZE + sizeof(uint8_t)];
-};
-
-static struct tpm_inf_dev g_tpm_dev CAR_GLOBAL;
-
-/*
- * iic_tpm_read() - read from TPM register
- *
- * @addr: register address to read from
- * @buffer: provided by caller
- * @len: number of bytes to read
- *
- * 1) send register address byte 'addr' to the TPM
- * 2) wait for TPM to indicate it is ready
- * 3) read 'len' bytes of TPM response into the provided 'buffer'
- *
- * Return -1 on error, 0 on success.
- */
-static int iic_tpm_read(uint8_t addr, uint8_t *buffer, size_t len)
-{
- struct tpm_inf_dev *tpm_dev = car_get_var_ptr(&g_tpm_dev);
-
- if (tpm_dev->addr == 0)
- return -1;
-
- /* Send the register address byte to the TPM */
- if (i2c_write_raw(tpm_dev->bus, tpm_dev->addr, &addr, 1)) {
- printk(BIOS_ERR, "%s: Address write failed\n", __func__);
- return -1;
- }
-
- /* Wait for TPM to be ready with response data */
- udelay(SLEEP_DURATION_SAFE);
-
- /* Read response data from the TPM */
- if (i2c_read_raw(tpm_dev->bus, tpm_dev->addr, buffer, len)) {
- printk(BIOS_ERR, "%s: Read response failed\n", __func__);
- return -1;
- }
-
- return 0;
-}
-
-/*
- * iic_tpm_write() - write to TPM register
- *
- * @addr: register address to write to
- * @buffer: data to write
- * @len: number of bytes to write
- *
- * 1) prepend the provided address to the provided data
- * 2) send the address+data to the TPM
- * 3) wait for TPM to indicate it is done writing
- *
- * Returns -1 on error, 0 on success.
- */
-static int iic_tpm_write(uint8_t addr, uint8_t *buffer, size_t len)
-{
- struct tpm_inf_dev *tpm_dev = car_get_var_ptr(&g_tpm_dev);
-
- if (tpm_dev->addr == 0)
- return -1;
- if (len > TPM_BUFSIZE)
- return -1;
-
- /* Prepend the 'register address' to the buffer */
- tpm_dev->buf[0] = addr;
- memcpy(tpm_dev->buf + 1, buffer, len);
-
- /* Send write request buffer with address */
- if (i2c_write_raw(tpm_dev->bus, tpm_dev->addr, tpm_dev->buf, len + 1)) {
- printk(BIOS_ERR, "%s: Error writing to TPM\n", __func__);
- return -1;
- }
-
- /* Wait for TPM to be ready */
- udelay(SLEEP_DURATION_SAFE);
-
- return 0;
-}
-
-static int check_locality(struct tpm_chip *chip, int loc)
-{
- uint8_t buf;
-
- if (iic_tpm_read(TPM_ACCESS(loc), &buf, 1) < 0)
- return -1;
-
- if ((buf & (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) ==
- (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) {
- chip->vendor.locality = loc;
- return loc;
- }
-
- return -1;
-}
-
-static void release_locality(struct tpm_chip *chip, int loc, int force)
-{
- uint8_t buf;
- if (iic_tpm_read(TPM_ACCESS(loc), &buf, 1) < 0)
- return;
-
- if (force || (buf & (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID)) ==
- (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID)) {
- buf = TPM_ACCESS_ACTIVE_LOCALITY;
- iic_tpm_write(TPM_ACCESS(loc), &buf, 1);
- }
-}
-
-static int request_locality(struct tpm_chip *chip, int loc)
-{
- uint8_t buf = TPM_ACCESS_REQUEST_USE;
-
- if (check_locality(chip, loc) >= 0)
- return loc; /* we already have the locality */
-
- iic_tpm_write(TPM_ACCESS(loc), &buf, 1);
-
- /* wait for burstcount */
- int timeout = 2 * 1000; /* 2s timeout */
- while (timeout) {
- if (check_locality(chip, loc) >= 0)
- return loc;
- mdelay(TPM_TIMEOUT);
- timeout--;
- }
-
- return -1;
-}
-
-/* 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(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;
-}
-
-static void cr50_vendor_init(struct tpm_chip *chip)
-{
- memset(&chip->vendor, 0, sizeof(struct tpm_vendor_specific));
- 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_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)
-{
- struct tpm_inf_dev *tpm_dev = car_get_var_ptr(&g_tpm_dev);
- struct stopwatch sw;
- uint8_t buf = 0;
- int ret;
- long sw_run_duration = SLEEP_DURATION_PROBE_MS;
-
- tpm_dev->bus = bus;
- tpm_dev->addr = addr;
-
- /* Wait for TPM_ACCESS register ValidSts bit to be set */
- stopwatch_init_msecs_expire(&sw, sw_run_duration);
- do {
- ret = iic_tpm_read(TPM_ACCESS(0), &buf, 1);
- if (!ret && (buf & TPM_STS_VALID)) {
- sw_run_duration = stopwatch_duration_msecs(&sw);
- break;
- }
- udelay(SLEEP_DURATION_SAFE);
- } while (!stopwatch_expired(&sw));
-
- printk(BIOS_INFO,
- "%s: ValidSts bit %s(%d) in TPM_ACCESS register after %ld ms\n",
- __func__, (buf & TPM_STS_VALID) ? "set" : "clear",
- (buf & TPM_STS_VALID) >> 7, sw_run_duration);
-
- /* Claim failure if the ValidSts (bit 7) is clear */
- if (!(buf & TPM_STS_VALID))
- return -1;
-
- return 0;
-}
-
-int tpm_vendor_init(struct tpm_chip *chip, unsigned bus, uint32_t dev_addr)
-{
- struct tpm_inf_dev *tpm_dev = car_get_var_ptr(&g_tpm_dev);
- uint32_t vendor;
-
- if (dev_addr == 0) {
- printk(BIOS_ERR, "%s: missing device address\n", __func__);
- return -1;
- }
-
- tpm_dev->bus = bus;
- tpm_dev->addr = dev_addr;
-
- cr50_vendor_init(chip);
-
- /* Disable interrupts (not supported) */
- chip->vendor.irq = 0;
-
- if (request_locality(chip, 0) != 0)
- return -1;
-
- /* Read four bytes from DID_VID register */
- if (iic_tpm_read(TPM_DID_VID(0), (uint8_t *)&vendor, 4) < 0)
- goto out_err;
-
- if (vendor != CR50_DID_VID) {
- printk(BIOS_DEBUG, "Vendor ID 0x%08x not recognized\n", vendor);
- goto out_err;
- }
-
- printk(BIOS_DEBUG, "cr50 TPM %u:%02x (device-id 0x%X)\n",
- tpm_dev->bus, tpm_dev->addr, vendor >> 16);
-
- chip->is_open = 1;
- return 0;
-
-out_err:
- release_locality(chip, 0, 1);
- return -1;
-}
-
-void tpm_vendor_cleanup(struct tpm_chip *chip)
-{
- release_locality(chip, chip->vendor.locality, 1);
-}