diff options
author | Stefan Reinauer <stefan.reinauer@coreboot.org> | 2012-04-27 02:31:28 +0200 |
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committer | Stefan Reinauer <stefan.reinauer@coreboot.org> | 2012-04-27 19:23:16 +0200 |
commit | ae5e11d7cd7484343d277fb454fb19fdff34730d (patch) | |
tree | 231aede3dcf80242a4e68e2b4268835f4bf1c5c6 /src/pc80/tpm.c | |
parent | aee1869fcf6c5eb1616f8c5c5a446c2b2de693e8 (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.c | 548 |
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); -} |