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authorStefan Reinauer <stefan.reinauer@coreboot.org>2012-04-27 02:31:28 +0200
committerStefan Reinauer <stefan.reinauer@coreboot.org>2012-04-27 19:23:16 +0200
commitae5e11d7cd7484343d277fb454fb19fdff34730d (patch)
tree231aede3dcf80242a4e68e2b4268835f4bf1c5c6 /src/pc80/tpm.c
parentaee1869fcf6c5eb1616f8c5c5a446c2b2de693e8 (diff)
Move top level pc80 directory to drivers/
There is no reason for this to be a top level directory. Some stuff from lib/ should also be moved to drivers/ Change-Id: I3c2d2e127f7215eadead029cfc7442c22b26814a Signed-off-by: Stefan Reinauer <reinauer@google.com> Reviewed-on: http://review.coreboot.org/939 Tested-by: build bot (Jenkins) Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Diffstat (limited to 'src/pc80/tpm.c')
-rw-r--r--src/pc80/tpm.c548
1 files changed, 0 insertions, 548 deletions
diff --git a/src/pc80/tpm.c b/src/pc80/tpm.c
deleted file mode 100644
index 17e1ed702d..0000000000
--- a/src/pc80/tpm.c
+++ /dev/null
@@ -1,548 +0,0 @@
-/*
- * This file is part of the coreboot project.
- *
- * Copyright (C) 2011 The Chromium OS Authors. All rights reserved.
- *
- * 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.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-/*
- * The code in this file has been heavily based on the article "Writing a TPM
- * Device Driver" published on http://ptgmedia.pearsoncmg.com and the
- * submission by Stefan Berger on Qemu-devel mailing list.
- *
- * One principal difference is that in the simplest config the other than 0
- * TPM localities do not get mapped by some devices (for instance, by
- * Infineon slb9635), so this driver provides access to locality 0 only.
- */
-
-#include <stdlib.h>
-#include <string.h>
-#include <delay.h>
-#include <arch/io.h>
-#include <arch/byteorder.h>
-#include <console/console.h>
-#include <pc80/tpm.h>
-#include <cpu/x86/car.h>
-
-#define PREFIX "lpc_tpm: "
-
-/* coreboot wrapper for TPM driver (start) */
-#define TPM_DEBUG(fmt, args...) \
- if (CONFIG_DEBUG_TPM) { \
- printk(BIOS_DEBUG, PREFIX); \
- printk(BIOS_DEBUG, fmt , ##args); \
- }
-#define printf(x...) printk(BIOS_ERR, x)
-
-#define min(a,b) MIN(a,b)
-#define max(a,b) MAX(a,b)
-#define readb(_a) (*(volatile unsigned char *) (_a))
-#define writeb(_v, _a) (*(volatile unsigned char *) (_a) = (_v))
-#define readl(_a) (*(volatile unsigned long *) (_a))
-#define writel(_v, _a) (*(volatile unsigned long *) (_a) = (_v))
-/* coreboot wrapper for TPM driver (end) */
-
-#ifndef CONFIG_TPM_TIS_BASE_ADDRESS
-/* Base TPM address standard for x86 systems */
-#define CONFIG_TPM_TIS_BASE_ADDRESS 0xfed40000
-#endif
-
-/* the macro accepts the locality value, but only locality 0 is operational */
-#define TIS_REG(LOCALITY, REG) \
- (void *)(CONFIG_TPM_TIS_BASE_ADDRESS + (LOCALITY << 12) + REG)
-
-/* hardware registers' offsets */
-#define TIS_REG_ACCESS 0x0
-#define TIS_REG_INT_ENABLE 0x8
-#define TIS_REG_INT_VECTOR 0xc
-#define TIS_REG_INT_STATUS 0x10
-#define TIS_REG_INTF_CAPABILITY 0x14
-#define TIS_REG_STS 0x18
-#define TIS_REG_DATA_FIFO 0x24
-#define TIS_REG_DID_VID 0xf00
-#define TIS_REG_RID 0xf04
-
-/* Some registers' bit field definitions */
-#define TIS_STS_VALID (1 << 7) /* 0x80 */
-#define TIS_STS_COMMAND_READY (1 << 6) /* 0x40 */
-#define TIS_STS_TPM_GO (1 << 5) /* 0x20 */
-#define TIS_STS_DATA_AVAILABLE (1 << 4) /* 0x10 */
-#define TIS_STS_EXPECT (1 << 3) /* 0x08 */
-#define TIS_STS_RESPONSE_RETRY (1 << 1) /* 0x02 */
-
-#define TIS_ACCESS_TPM_REG_VALID_STS (1 << 7) /* 0x80 */
-#define TIS_ACCESS_ACTIVE_LOCALITY (1 << 5) /* 0x20 */
-#define TIS_ACCESS_BEEN_SEIZED (1 << 4) /* 0x10 */
-#define TIS_ACCESS_SEIZE (1 << 3) /* 0x08 */
-#define TIS_ACCESS_PENDING_REQUEST (1 << 2) /* 0x04 */
-#define TIS_ACCESS_REQUEST_USE (1 << 1) /* 0x02 */
-#define TIS_ACCESS_TPM_ESTABLISHMENT (1 << 0) /* 0x01 */
-
-#define TIS_STS_BURST_COUNT_MASK (0xffff)
-#define TIS_STS_BURST_COUNT_SHIFT (8)
-
-/*
- * Error value returned if a tpm register does not enter the expected state
- * after continuous polling. No actual TPM register reading ever returns ~0,
- * so this value is a safe error indication to be mixed with possible status
- * register values.
- */
-#define TPM_TIMEOUT_ERR (~0)
-
-/* Error value returned on various TPM driver errors */
-#define TPM_DRIVER_ERR (~0)
-
- /* 1 second is plenty for anything TPM does.*/
-#define MAX_DELAY_US (1000 * 1000)
-
-/* Retrieve burst count value out of the status register contents. */
-#define BURST_COUNT(status) ((u16)(((status) >> TIS_STS_BURST_COUNT_SHIFT) & \
- TIS_STS_BURST_COUNT_MASK))
-
-/*
- * Structures defined below allow creating descriptions of TPM vendor/device
- * ID information for run time discovery. The only device the system knows
- * about at this time is Infineon slb9635
- */
-struct device_name {
- u16 dev_id;
- const char * const dev_name;
-};
-
-struct vendor_name {
- u16 vendor_id;
- const char * vendor_name;
- const struct device_name* dev_names;
-};
-
-static const struct device_name infineon_devices[] = {
- {0xb, "SLB9635 TT 1.2"},
- {0}
-};
-
-static const struct vendor_name vendor_names[] = {
- {0x15d1, "Infineon", infineon_devices},
-};
-
-/*
- * Cached vendor/device ID pair to indicate that the device has been already
- * discovered
- */
-static u32 vendor_dev_id CAR_GLOBAL;
-
-static int is_byte_reg(u32 reg)
-{
- /*
- * These TPM registers are 8 bits wide and as such require byte access
- * on writes and truncated value on reads.
- */
- return ((reg == TIS_REG_ACCESS) ||
- (reg == TIS_REG_INT_VECTOR) ||
- (reg == TIS_REG_DATA_FIFO));
-}
-
-/* TPM access functions are carved out to make tracing easier. */
-static u32 tpm_read(int locality, u32 reg)
-{
- u32 value;
- /*
- * Data FIFO register must be read and written in byte access mode,
- * otherwise the FIFO values are returned 4 bytes at a time.
- */
- if (is_byte_reg(reg))
- value = readb(TIS_REG(locality, reg));
- else
- value = readl(TIS_REG(locality, reg));
-
- TPM_DEBUG("Read reg 0x%x returns 0x%x\n", reg, value);
- return value;
-}
-
-static void tpm_write(u32 value, int locality, u32 reg)
-{
- TPM_DEBUG("Write reg 0x%x with 0x%x\n", reg, value);
-
- if (is_byte_reg(reg))
- writeb(value & 0xff, TIS_REG(locality, reg));
- else
- writel(value, TIS_REG(locality, reg));
-}
-
-/*
- * tis_wait_reg()
- *
- * Wait for at least a second for a register to change its state to match the
- * expected state. Normally the transition happens within microseconds.
- *
- * @reg - the TPM register offset
- * @locality - locality
- * @mask - bitmask for the bitfield(s) to watch
- * @expected - value the field(s) are supposed to be set to
- *
- * Returns the register contents in case the expected value was found in the
- * appropriate register bits, or TPM_TIMEOUT_ERR on timeout.
- */
-static u32 tis_wait_reg(u8 reg, u8 locality, u8 mask, u8 expected)
-{
- u32 time_us = MAX_DELAY_US;
- while (time_us > 0) {
- u32 value = tpm_read(locality, reg);
- if ((value & mask) == expected)
- return value;
- udelay(1); /* 1 us */
- time_us--;
- }
- return TPM_TIMEOUT_ERR;
-}
-
-/*
- * Probe the TPM device and try determining its manufacturer/device name.
- *
- * Returns 0 on success (the device is found or was found during an earlier
- * invocation) or TPM_DRIVER_ERR if the device is not found.
- */
-static u32 tis_probe(void)
-{
- u32 didvid = tpm_read(0, TIS_REG_DID_VID);
- int i;
- const char *device_name = "unknown";
- const char *vendor_name = device_name;
- u16 vid, did;
-
- if (vendor_dev_id)
- return 0; /* Already probed. */
-
- if (!didvid || (didvid == 0xffffffff)) {
- printf("%s: No TPM device found\n", __FUNCTION__);
- return TPM_DRIVER_ERR;
- }
-
- vendor_dev_id = didvid;
-
- vid = didvid & 0xffff;
- did = (didvid >> 16) & 0xffff;
- for (i = 0; i < ARRAY_SIZE(vendor_names); i++) {
- int j = 0;
- u16 known_did;
- if (vid == vendor_names[i].vendor_id) {
- vendor_name = vendor_names[i].vendor_name;
- }
- while ((known_did = vendor_names[i].dev_names[j].dev_id) != 0) {
- if (known_did == did) {
- device_name =
- vendor_names[i].dev_names[j].dev_name;
- break;
- }
- j++;
- }
- break;
- }
- /* this will have to be converted into debug printout */
- TPM_DEBUG("Found TPM %s by %s\n", device_name, vendor_name);
- return 0;
-}
-
-/*
- * tis_senddata()
- *
- * send the passed in data to the TPM device.
- *
- * @data - address of the data to send, byte by byte
- * @len - length of the data to send
- *
- * Returns 0 on success, TPM_DRIVER_ERR on error (in case the device does
- * not accept the entire command).
- */
-static u32 tis_senddata(const u8 * const data, u32 len)
-{
- u32 offset = 0;
- u16 burst = 0;
- u32 max_cycles = 0;
- u8 locality = 0;
- u32 value;
-
- value = tis_wait_reg(TIS_REG_STS, locality, TIS_STS_COMMAND_READY,
- TIS_STS_COMMAND_READY);
- if (value == TPM_TIMEOUT_ERR) {
- printf("%s:%d - failed to get 'command_ready' status\n",
- __FILE__, __LINE__);
- return TPM_DRIVER_ERR;
- }
- burst = BURST_COUNT(value);
-
- while (1) {
- unsigned count;
-
- /* Wait till the device is ready to accept more data. */
- while (!burst) {
- if (max_cycles++ == MAX_DELAY_US) {
- printf("%s:%d failed to feed %d bytes of %d\n",
- __FILE__, __LINE__, len - offset, len);
- return TPM_DRIVER_ERR;
- }
- udelay(1);
- burst = BURST_COUNT(tpm_read(locality, TIS_REG_STS));
- }
-
- max_cycles = 0;
-
- /*
- * Calculate number of bytes the TPM is ready to accept in one
- * shot.
- *
- * We want to send the last byte outside of the loop (hence
- * the -1 below) to make sure that the 'expected' status bit
- * changes to zero exactly after the last byte is fed into the
- * FIFO.
- */
- count = min(burst, len - offset - 1);
- while (count--)
- tpm_write(data[offset++], locality, TIS_REG_DATA_FIFO);
-
- value = tis_wait_reg(TIS_REG_STS, locality,
- TIS_STS_VALID, TIS_STS_VALID);
-
- if ((value == TPM_TIMEOUT_ERR) || !(value & TIS_STS_EXPECT)) {
- printf("%s:%d TPM command feed overflow\n",
- __FILE__, __LINE__);
- return TPM_DRIVER_ERR;
- }
-
- burst = BURST_COUNT(value);
- if ((offset == (len - 1)) && burst)
- /*
- * We need to be able to send the last byte to the
- * device, so burst size must be nonzero before we
- * break out.
- */
- break;
- }
-
- /* Send the last byte. */
- tpm_write(data[offset++], locality, TIS_REG_DATA_FIFO);
-
- /*
- * Verify that TPM does not expect any more data as part of this
- * command.
- */
- value = tis_wait_reg(TIS_REG_STS, locality,
- TIS_STS_VALID, TIS_STS_VALID);
- if ((value == TPM_TIMEOUT_ERR) || (value & TIS_STS_EXPECT)) {
- printf("%s:%d unexpected TPM status 0x%x\n",
- __FILE__, __LINE__, value);
- return TPM_DRIVER_ERR;
- }
-
- /* OK, sitting pretty, let's start the command execution. */
- tpm_write(TIS_STS_TPM_GO, locality, TIS_REG_STS);
-
- return 0;
-}
-
-/*
- * tis_readresponse()
- *
- * read the TPM device response after a command was issued.
- *
- * @buffer - address where to read the response, byte by byte.
- * @len - pointer to the size of buffer
- *
- * On success stores the number of received bytes to len and returns 0. On
- * errors (misformatted TPM data or synchronization problems) returns
- * TPM_DRIVER_ERR.
- */
-static u32 tis_readresponse(u8 *buffer, size_t *len)
-{
- u16 burst_count;
- u32 status;
- u32 offset = 0;
- u8 locality = 0;
- const u32 has_data = TIS_STS_DATA_AVAILABLE | TIS_STS_VALID;
- u32 expected_count = *len;
- int max_cycles = 0;
-
- /* Wait for the TPM to process the command */
- status = tis_wait_reg(TIS_REG_STS, locality, has_data, has_data);
- if (status == TPM_TIMEOUT_ERR) {
- printf("%s:%d failed processing command\n",
- __FILE__, __LINE__);
- return TPM_DRIVER_ERR;
- }
-
- do {
- while ((burst_count = BURST_COUNT(status)) == 0) {
- if (max_cycles++ == MAX_DELAY_US) {
- printf("%s:%d TPM stuck on read\n",
- __FILE__, __LINE__);
- return TPM_DRIVER_ERR;
- }
- udelay(1);
- status = tpm_read(locality, TIS_REG_STS);
- }
-
- max_cycles = 0;
-
- while (burst_count-- && (offset < expected_count)) {
- buffer[offset++] = (u8) tpm_read(locality,
- TIS_REG_DATA_FIFO);
- if (offset == 6) {
- /*
- * We got the first six bytes of the reply,
- * let's figure out how many bytes to expect
- * total - it is stored as a 4 byte number in
- * network order, starting with offset 2 into
- * the body of the reply.
- */
- u32 real_length;
- memcpy(&real_length,
- buffer + 2,
- sizeof(real_length));
- expected_count = be32_to_cpu(real_length);
-
- if ((expected_count < offset) ||
- (expected_count > *len)) {
- printf("%s:%d bad response size %d\n",
- __FILE__, __LINE__,
- expected_count);
- return TPM_DRIVER_ERR;
- }
- }
- }
-
- /* Wait for the next portion */
- status = tis_wait_reg(TIS_REG_STS, locality,
- TIS_STS_VALID, TIS_STS_VALID);
- if (status == TPM_TIMEOUT_ERR) {
- printf("%s:%d failed to read response\n",
- __FILE__, __LINE__);
- return TPM_DRIVER_ERR;
- }
-
- if (offset == expected_count)
- break; /* We got all we need */
-
- } while ((status & has_data) == has_data);
-
- /*
- * Make sure we indeed read all there was. The TIS_STS_VALID bit is
- * known to be set.
- */
- if (status & TIS_STS_DATA_AVAILABLE) {
- printf("%s:%d wrong receive status %x\n",
- __FILE__, __LINE__, status);
- return TPM_DRIVER_ERR;
- }
-
- /* Tell the TPM that we are done. */
- tpm_write(TIS_STS_COMMAND_READY, locality, TIS_REG_STS);
-
- *len = offset;
- return 0;
-}
-
-/*
- * tis_init()
- *
- * Initialize the TPM device. Returns 0 on success or TPM_DRIVER_ERR on
- * failure (in case device probing did not succeed).
- */
-int tis_init(void)
-{
- if (tis_probe())
- return TPM_DRIVER_ERR;
- return 0;
-}
-
-/*
- * tis_open()
- *
- * Requests access to locality 0 for the caller. After all commands have been
- * completed the caller is supposed to call tis_close().
- *
- * Returns 0 on success, TPM_DRIVER_ERR on failure.
- */
-int tis_open(void)
-{
- u8 locality = 0; /* we use locality zero for everything */
-
- if (tis_close())
- return TPM_DRIVER_ERR;
-
- /* now request access to locality */
- tpm_write(TIS_ACCESS_REQUEST_USE, locality, TIS_REG_ACCESS);
-
- /* did we get a lock? */
- if (tis_wait_reg(TIS_REG_ACCESS, locality,
- TIS_ACCESS_ACTIVE_LOCALITY,
- TIS_ACCESS_ACTIVE_LOCALITY) == TPM_TIMEOUT_ERR) {
- printf("%s:%d - failed to lock locality %d\n",
- __FILE__, __LINE__, locality);
- return TPM_DRIVER_ERR;
- }
-
- tpm_write(TIS_STS_COMMAND_READY, locality, TIS_REG_STS);
-
- return 0;
-}
-
-/*
- * tis_close()
- *
- * terminate the currect session with the TPM by releasing the locked
- * locality. Returns 0 on success of TPM_DRIVER_ERR on failure (in case lock
- * removal did not succeed).
- */
-int tis_close(void)
-{
- u8 locality = 0;
- if (tpm_read(locality, TIS_REG_ACCESS) &
- TIS_ACCESS_ACTIVE_LOCALITY) {
- tpm_write(TIS_ACCESS_ACTIVE_LOCALITY, locality, TIS_REG_ACCESS);
-
- if (tis_wait_reg(TIS_REG_ACCESS, locality,
- TIS_ACCESS_ACTIVE_LOCALITY, 0) ==
- TPM_TIMEOUT_ERR) {
- printf("%s:%d - failed to release locality %d\n",
- __FILE__, __LINE__, locality);
- return TPM_DRIVER_ERR;
- }
- }
- return 0;
-}
-
-/*
- * tis_sendrecv()
- *
- * Send the requested data to the TPM and then try to get its response
- *
- * @sendbuf - buffer of the data to send
- * @send_size size of the data to send
- * @recvbuf - memory to save the response to
- * @recv_len - pointer to the size of the response buffer
- *
- * Returns 0 on success (and places the number of response bytes at recv_len)
- * or TPM_DRIVER_ERR on failure.
- */
-int tis_sendrecv(const uint8_t *sendbuf, size_t send_size,
- uint8_t *recvbuf, size_t *recv_len)
-{
- if (tis_senddata(sendbuf, send_size)) {
- printf("%s:%d failed sending data to TPM\n",
- __FILE__, __LINE__);
- return TPM_DRIVER_ERR;
- }
-
- return tis_readresponse(recvbuf, recv_len);
-}