Stefan Reinauer (stefan.reinauer@coreboot.org) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/9468
-gerrit
commit 2924225bdf710d9bd3216fdc0b599c7d75007b16 Author: Duncan Laurie dlaurie@chromium.org Date: Thu Oct 30 15:11:48 2014 -0700
tpm: Move the LPC TPM driver to a subdirectory
This moves the LPC TPM driver to drivers/pc80/tpm so it can be turned into a ramstage driver with a chip.h
It includes no other changes yet.
BUG=chrome-os-partner:33385 BRANCH=samus,auron TEST=emerge-samus coreboot
Change-Id: Iac83e52db96201f37a0086eae9df244f8b8d48d9 Signed-off-by: Stefan Reinauer reinauer@chromium.org Original-Commit-Id: be2db391f9da80b8b75137af0fe81dc4724bc9d1 Original-Change-Id: I60ddd1d2a3e72bcf169a0b44e0c7ebcb87f4617d Original-Signed-off-by: Duncan Laurie dlaurie@chromium.org Original-Reviewed-on: https://chromium-review.googlesource.com/226660 Original-Reviewed-by: Aaron Durbin adurbin@chromium.org --- src/drivers/pc80/Kconfig | 10 +- src/drivers/pc80/Makefile.inc | 3 +- src/drivers/pc80/tpm.c | 675 -------------------------------------- src/drivers/pc80/tpm/Kconfig | 7 + src/drivers/pc80/tpm/Makefile.inc | 1 + src/drivers/pc80/tpm/tpm.c | 675 ++++++++++++++++++++++++++++++++++++++ 6 files changed, 686 insertions(+), 685 deletions(-)
diff --git a/src/drivers/pc80/Kconfig b/src/drivers/pc80/Kconfig index f6da88c..a1e94ab 100644 --- a/src/drivers/pc80/Kconfig +++ b/src/drivers/pc80/Kconfig @@ -17,16 +17,10 @@ config DRIVERS_PS2_KEYBOARD this option, then you can say N here to speed up boot time. Otherwise say Y.
-config LPC_TPM - bool - default n - help - Enable this option to enable TPM support in coreboot. - - If unsure, say N. - config DRIVERS_MC146818 bool default y if ARCH_X86
+source src/drivers/pc80/tpm/Kconfig + endif diff --git a/src/drivers/pc80/Makefile.inc b/src/drivers/pc80/Makefile.inc index 9715949..be8e8ea 100644 --- a/src/drivers/pc80/Makefile.inc +++ b/src/drivers/pc80/Makefile.inc @@ -9,10 +9,9 @@ ramstage-$(CONFIG_SPKMODEM) += spkmodem.c
romstage-$(CONFIG_DRIVERS_MC146818) += mc146818rtc_early.c
-romstage-$(CONFIG_LPC_TPM) += tpm.c romstage-$(CONFIG_SPKMODEM) += spkmodem.c
-subdirs-y += vga +subdirs-y += tpm vga
cbfs-files-$(CONFIG_HAVE_CMOS_DEFAULT) += cmos.default cmos.default-file = $(CONFIG_CMOS_DEFAULT_FILE):nvramtool diff --git a/src/drivers/pc80/tpm.c b/src/drivers/pc80/tpm.c deleted file mode 100644 index c0429dd..0000000 --- a/src/drivers/pc80/tpm.c +++ /dev/null @@ -1,675 +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 <tpm.h> -#include <arch/early_variables.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 TPM_DEBUG_IO_READ(reg_, val_) \ - TPM_DEBUG("Read reg 0x%x returns 0x%x\n", (reg_), (val_)) -#define TPM_DEBUG_IO_WRITE(reg_, val_) \ - TPM_DEBUG("Write reg 0x%x with 0x%x\n", (reg_), (val_)) -#define printf(x...) printk(BIOS_ERR, x) - -#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_BURST_COUNT 0x19 -#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 */ - -/* - * 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) - -/* - * 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 atmel_devices[] = { - {0x3204, "AT97SC3204"}, - {0xffff} -}; - -static const struct device_name infineon_devices[] = { - {0x000b, "SLB9635 TT 1.2"}, - {0xffff} -}; - -static const struct device_name nuvoton_devices[] = { - {0x00fe, "NPCT420AA V2"}, - {0xffff} -}; - -static const struct device_name stmicro_devices[] = { - {0x0000, "ST33ZP24" }, - {0xffff} -}; - -static const struct vendor_name vendor_names[] = { - {0x1114, "Atmel", atmel_devices}, - {0x15d1, "Infineon", infineon_devices}, - {0x1050, "Nuvoton", nuvoton_devices}, - {0x104a, "ST Microelectronics", stmicro_devices}, -}; - -/* - * Cached vendor/device ID pair to indicate that the device has been already - * discovered - */ -static u32 vendor_dev_id CAR_GLOBAL; - -static inline u8 tpm_read_status(int locality) -{ - u8 value = readb(TIS_REG(locality, TIS_REG_STS)); - TPM_DEBUG_IO_READ(TIS_REG_STS, value); - return value; -} - -static inline void tpm_write_status(u8 sts, int locality) -{ - TPM_DEBUG_IO_WRITE(TIS_REG_STS, sts); - writeb(sts, TIS_REG(locality, TIS_REG_STS)); -} - -static inline u8 tpm_read_data(int locality) -{ - u8 value = readb(TIS_REG(locality, TIS_REG_DATA_FIFO)); - TPM_DEBUG_IO_READ(TIS_REG_DATA_FIFO, value); - return value; -} - -static inline void tpm_write_data(u8 data, int locality) -{ - TPM_DEBUG_IO_WRITE(TIS_REG_STS, data); - writeb(data, TIS_REG(locality, TIS_REG_DATA_FIFO)); -} - -static inline u16 tpm_read_burst_count(int locality) -{ - u16 count; - count = readb(TIS_REG(locality, TIS_REG_BURST_COUNT)); - count |= readb(TIS_REG(locality, TIS_REG_BURST_COUNT + 1)) << 8; - TPM_DEBUG_IO_READ(TIS_REG_BURST_COUNT, count); - return count; -} - -static inline u8 tpm_read_access(int locality) -{ - u8 value = readb(TIS_REG(locality, TIS_REG_ACCESS)); - TPM_DEBUG_IO_READ(TIS_REG_ACCESS, value); - return value; -} - -static inline void tpm_write_access(u8 data, int locality) -{ - TPM_DEBUG_IO_WRITE(TIS_REG_ACCESS, data); - writeb(data, TIS_REG(locality, TIS_REG_ACCESS)); -} - -static inline u32 tpm_read_did_vid(int locality) -{ - u32 value = readl(TIS_REG(locality, TIS_REG_DID_VID)); - TPM_DEBUG_IO_READ(TIS_REG_DID_VID, value); - return value; -} - -/* - * tis_wait_sts() - * - * Wait for at least a second for a status to change its state to match the - * expected state. Normally the transition happens within microseconds. - * - * @locality - locality - * @mask - bitmask for the bitfield(s) to watch - * @expected - value the field(s) are supposed to be set to - * - * Returns 0 on success or TPM_TIMEOUT_ERR on timeout. - */ -static int tis_wait_sts(int locality, u8 mask, u8 expected) -{ - u32 time_us = MAX_DELAY_US; - while (time_us > 0) { - u8 value = tpm_read_status(locality); - if ((value & mask) == expected) - return 0; - udelay(1); /* 1 us */ - time_us--; - } - return TPM_TIMEOUT_ERR; -} - -static inline int tis_wait_ready(int locality) -{ - return tis_wait_sts(locality, TIS_STS_COMMAND_READY, - TIS_STS_COMMAND_READY); -} - -static inline int tis_wait_valid(int locality) -{ - return tis_wait_sts(locality, TIS_STS_VALID, TIS_STS_VALID); -} - -static inline int tis_wait_valid_data(int locality) -{ - const u8 has_data = TIS_STS_DATA_AVAILABLE | TIS_STS_VALID; - return tis_wait_sts(locality, has_data, has_data); -} - -static inline int tis_has_valid_data(int locality) -{ - const u8 has_data = TIS_STS_DATA_AVAILABLE | TIS_STS_VALID; - return (tpm_read_status(locality) & has_data) == has_data; -} - -static inline int tis_expect_data(int locality) -{ - return !!(tpm_read_status(locality) & TIS_STS_EXPECT); -} - -/* - * tis_wait_access() - * - * Wait for at least a second for a access to change its state to match the - * expected state. Normally the transition happens within microseconds. - * - * @locality - locality - * @mask - bitmask for the bitfield(s) to watch - * @expected - value the field(s) are supposed to be set to - * - * Returns 0 on success or TPM_TIMEOUT_ERR on timeout. - */ -static int tis_wait_access(int locality, u8 mask, u8 expected) -{ - u32 time_us = MAX_DELAY_US; - while (time_us > 0) { - u8 value = tpm_read_access(locality); - if ((value & mask) == expected) - return 0; - udelay(1); /* 1 us */ - time_us--; - } - return TPM_TIMEOUT_ERR; -} - -static inline int tis_wait_dropped_access(int locality) -{ - return tis_wait_access(locality, TIS_ACCESS_ACTIVE_LOCALITY, 0); -} - -static inline int tis_wait_received_access(int locality) -{ - return tis_wait_access(locality, TIS_ACCESS_ACTIVE_LOCALITY, - TIS_ACCESS_ACTIVE_LOCALITY); -} - -static inline int tis_has_access(int locality) -{ - return !!(tpm_read_access(locality) & TIS_ACCESS_ACTIVE_LOCALITY); -} - -static inline void tis_request_access(int locality) -{ - tpm_write_access(TIS_ACCESS_REQUEST_USE, locality); -} - -static inline void tis_drop_access(int locality) -{ - tpm_write_access(TIS_ACCESS_ACTIVE_LOCALITY, locality); -} - -/* - * PC Client Specific TPM Interface Specification section 11.2.12: - * - * Software must be prepared to send two writes of a "1" to command ready - * field: the first to indicate successful read of all the data, thus - * clearing the data from the ReadFIFO and freeing the TPM's resources, - * and the second to indicate to the TPM it is about to send a new command. - * - * In practice not all TPMs behave the same so it is necessary to be - * flexible when trying to set command ready. - * - * Returns 0 on success if the TPM is ready for transactions. - * Returns TPM_TIMEOUT_ERR if the command ready bit does not get set. - */ -static int tis_command_ready(u8 locality) -{ - u32 status; - - /* 1st attempt to set command ready */ - tpm_write_status(TIS_STS_COMMAND_READY, locality); - - /* Wait for response */ - status = tpm_read_status(locality); - - /* Check if command ready is set yet */ - if (status & TIS_STS_COMMAND_READY) - return 0; - - /* 2nd attempt to set command ready */ - tpm_write_status(TIS_STS_COMMAND_READY, locality); - - return tis_wait_ready(locality); -} - -/* - * 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) -{ - const char *device_name = "unknown"; - const char *vendor_name = device_name; - const struct device_name *dev; - u32 didvid; - u16 vid, did; - int i; - - if (car_get_var(vendor_dev_id)) - return 0; /* Already probed. */ - - didvid = tpm_read_did_vid(0); - if (!didvid || (didvid == 0xffffffff)) { - printf("%s: No TPM device found\n", __FUNCTION__); - return TPM_DRIVER_ERR; - } - - car_set_var(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; - } else { - continue; - } - dev = &vendor_names[i].dev_names[j]; - while ((known_did = dev->dev_id) != 0xffff) { - if (known_did == did) { - device_name = dev->dev_name; - break; - } - j++; - } - break; - } - /* this will have to be converted into debug printout */ - printf("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; - - if (tis_wait_ready(locality)) { - printf("%s:%d - failed to get 'command_ready' status\n", - __FILE__, __LINE__); - return TPM_DRIVER_ERR; - } - burst = tpm_read_burst_count(locality); - - 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 = tpm_read_burst_count(locality); - } - - 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(data[offset++], locality); - - if (tis_wait_valid(locality) || !tis_expect_data(locality)) { - printf("%s:%d TPM command feed overflow\n", - __FILE__, __LINE__); - return TPM_DRIVER_ERR; - } - - burst = tpm_read_burst_count(locality); - 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(data[offset++], locality); - - /* - * Verify that TPM does not expect any more data as part of this - * command. - */ - if (tis_wait_valid(locality) || tis_expect_data(locality)) { - printf("%s:%d unexpected TPM status 0x%x\n", - __FILE__, __LINE__, tpm_read_status(locality)); - return TPM_DRIVER_ERR; - } - - /* OK, sitting pretty, let's start the command execution. */ - tpm_write_status(TIS_STS_TPM_GO, locality); - - 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 offset = 0; - u8 locality = 0; - u32 expected_count = *len; - int max_cycles = 0; - - /* Wait for the TPM to process the command */ - if (tis_wait_valid_data(locality)) { - printf("%s:%d failed processing command\n", __FILE__, __LINE__); - return TPM_DRIVER_ERR; - } - - do { - while ((burst_count = tpm_read_burst_count(locality)) == 0) { - if (max_cycles++ == MAX_DELAY_US) { - printf("%s:%d TPM stuck on read\n", - __FILE__, __LINE__); - return TPM_DRIVER_ERR; - } - udelay(1); - } - - max_cycles = 0; - - while (burst_count-- && (offset < expected_count)) { - buffer[offset++] = tpm_read_data(locality); - 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 */ - if (tis_wait_valid(locality)) { - 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 (tis_has_valid_data(locality)); - - /* * Make sure we indeed read all there was. */ - if (tis_has_valid_data(locality)) { - printf("%s:%d wrong receive status: %x %d bytes left\n", - __FILE__, __LINE__, tpm_read_status(locality), - tpm_read_burst_count(locality)); - return TPM_DRIVER_ERR; - } - - /* Tell the TPM that we are done. */ - if (tis_command_ready(locality) == TPM_TIMEOUT_ERR) - return TPM_DRIVER_ERR; - - *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 */ - tis_request_access(locality); - - /* did we get a lock? */ - if (tis_wait_received_access(locality)) { - printf("%s:%d - failed to lock locality %d\n", - __FILE__, __LINE__, locality); - return TPM_DRIVER_ERR; - } - - /* Certain TPMs seem to need some delay here or they hang... */ - udelay(10); - - if (tis_command_ready(locality) == TPM_TIMEOUT_ERR) - return TPM_DRIVER_ERR; - - return 0; -} - -/* - * tis_close() - * - * terminate the current 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 (tis_has_access(locality)) { - tis_drop_access(locality); - if (tis_wait_dropped_access(locality)) { - 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); -} diff --git a/src/drivers/pc80/tpm/Kconfig b/src/drivers/pc80/tpm/Kconfig new file mode 100644 index 0000000..fbb3b42 --- /dev/null +++ b/src/drivers/pc80/tpm/Kconfig @@ -0,0 +1,7 @@ +config LPC_TPM + bool + default n + help + Enable this option to enable LPC TPM support in coreboot. + + If unsure, say N. diff --git a/src/drivers/pc80/tpm/Makefile.inc b/src/drivers/pc80/tpm/Makefile.inc new file mode 100644 index 0000000..6f973e1 --- /dev/null +++ b/src/drivers/pc80/tpm/Makefile.inc @@ -0,0 +1 @@ +romstage-$(CONFIG_LPC_TPM) += tpm.c diff --git a/src/drivers/pc80/tpm/tpm.c b/src/drivers/pc80/tpm/tpm.c new file mode 100644 index 0000000..c0429dd --- /dev/null +++ b/src/drivers/pc80/tpm/tpm.c @@ -0,0 +1,675 @@ +/* + * 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 <tpm.h> +#include <arch/early_variables.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 TPM_DEBUG_IO_READ(reg_, val_) \ + TPM_DEBUG("Read reg 0x%x returns 0x%x\n", (reg_), (val_)) +#define TPM_DEBUG_IO_WRITE(reg_, val_) \ + TPM_DEBUG("Write reg 0x%x with 0x%x\n", (reg_), (val_)) +#define printf(x...) printk(BIOS_ERR, x) + +#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_BURST_COUNT 0x19 +#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 */ + +/* + * 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) + +/* + * 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 atmel_devices[] = { + {0x3204, "AT97SC3204"}, + {0xffff} +}; + +static const struct device_name infineon_devices[] = { + {0x000b, "SLB9635 TT 1.2"}, + {0xffff} +}; + +static const struct device_name nuvoton_devices[] = { + {0x00fe, "NPCT420AA V2"}, + {0xffff} +}; + +static const struct device_name stmicro_devices[] = { + {0x0000, "ST33ZP24" }, + {0xffff} +}; + +static const struct vendor_name vendor_names[] = { + {0x1114, "Atmel", atmel_devices}, + {0x15d1, "Infineon", infineon_devices}, + {0x1050, "Nuvoton", nuvoton_devices}, + {0x104a, "ST Microelectronics", stmicro_devices}, +}; + +/* + * Cached vendor/device ID pair to indicate that the device has been already + * discovered + */ +static u32 vendor_dev_id CAR_GLOBAL; + +static inline u8 tpm_read_status(int locality) +{ + u8 value = readb(TIS_REG(locality, TIS_REG_STS)); + TPM_DEBUG_IO_READ(TIS_REG_STS, value); + return value; +} + +static inline void tpm_write_status(u8 sts, int locality) +{ + TPM_DEBUG_IO_WRITE(TIS_REG_STS, sts); + writeb(sts, TIS_REG(locality, TIS_REG_STS)); +} + +static inline u8 tpm_read_data(int locality) +{ + u8 value = readb(TIS_REG(locality, TIS_REG_DATA_FIFO)); + TPM_DEBUG_IO_READ(TIS_REG_DATA_FIFO, value); + return value; +} + +static inline void tpm_write_data(u8 data, int locality) +{ + TPM_DEBUG_IO_WRITE(TIS_REG_STS, data); + writeb(data, TIS_REG(locality, TIS_REG_DATA_FIFO)); +} + +static inline u16 tpm_read_burst_count(int locality) +{ + u16 count; + count = readb(TIS_REG(locality, TIS_REG_BURST_COUNT)); + count |= readb(TIS_REG(locality, TIS_REG_BURST_COUNT + 1)) << 8; + TPM_DEBUG_IO_READ(TIS_REG_BURST_COUNT, count); + return count; +} + +static inline u8 tpm_read_access(int locality) +{ + u8 value = readb(TIS_REG(locality, TIS_REG_ACCESS)); + TPM_DEBUG_IO_READ(TIS_REG_ACCESS, value); + return value; +} + +static inline void tpm_write_access(u8 data, int locality) +{ + TPM_DEBUG_IO_WRITE(TIS_REG_ACCESS, data); + writeb(data, TIS_REG(locality, TIS_REG_ACCESS)); +} + +static inline u32 tpm_read_did_vid(int locality) +{ + u32 value = readl(TIS_REG(locality, TIS_REG_DID_VID)); + TPM_DEBUG_IO_READ(TIS_REG_DID_VID, value); + return value; +} + +/* + * tis_wait_sts() + * + * Wait for at least a second for a status to change its state to match the + * expected state. Normally the transition happens within microseconds. + * + * @locality - locality + * @mask - bitmask for the bitfield(s) to watch + * @expected - value the field(s) are supposed to be set to + * + * Returns 0 on success or TPM_TIMEOUT_ERR on timeout. + */ +static int tis_wait_sts(int locality, u8 mask, u8 expected) +{ + u32 time_us = MAX_DELAY_US; + while (time_us > 0) { + u8 value = tpm_read_status(locality); + if ((value & mask) == expected) + return 0; + udelay(1); /* 1 us */ + time_us--; + } + return TPM_TIMEOUT_ERR; +} + +static inline int tis_wait_ready(int locality) +{ + return tis_wait_sts(locality, TIS_STS_COMMAND_READY, + TIS_STS_COMMAND_READY); +} + +static inline int tis_wait_valid(int locality) +{ + return tis_wait_sts(locality, TIS_STS_VALID, TIS_STS_VALID); +} + +static inline int tis_wait_valid_data(int locality) +{ + const u8 has_data = TIS_STS_DATA_AVAILABLE | TIS_STS_VALID; + return tis_wait_sts(locality, has_data, has_data); +} + +static inline int tis_has_valid_data(int locality) +{ + const u8 has_data = TIS_STS_DATA_AVAILABLE | TIS_STS_VALID; + return (tpm_read_status(locality) & has_data) == has_data; +} + +static inline int tis_expect_data(int locality) +{ + return !!(tpm_read_status(locality) & TIS_STS_EXPECT); +} + +/* + * tis_wait_access() + * + * Wait for at least a second for a access to change its state to match the + * expected state. Normally the transition happens within microseconds. + * + * @locality - locality + * @mask - bitmask for the bitfield(s) to watch + * @expected - value the field(s) are supposed to be set to + * + * Returns 0 on success or TPM_TIMEOUT_ERR on timeout. + */ +static int tis_wait_access(int locality, u8 mask, u8 expected) +{ + u32 time_us = MAX_DELAY_US; + while (time_us > 0) { + u8 value = tpm_read_access(locality); + if ((value & mask) == expected) + return 0; + udelay(1); /* 1 us */ + time_us--; + } + return TPM_TIMEOUT_ERR; +} + +static inline int tis_wait_dropped_access(int locality) +{ + return tis_wait_access(locality, TIS_ACCESS_ACTIVE_LOCALITY, 0); +} + +static inline int tis_wait_received_access(int locality) +{ + return tis_wait_access(locality, TIS_ACCESS_ACTIVE_LOCALITY, + TIS_ACCESS_ACTIVE_LOCALITY); +} + +static inline int tis_has_access(int locality) +{ + return !!(tpm_read_access(locality) & TIS_ACCESS_ACTIVE_LOCALITY); +} + +static inline void tis_request_access(int locality) +{ + tpm_write_access(TIS_ACCESS_REQUEST_USE, locality); +} + +static inline void tis_drop_access(int locality) +{ + tpm_write_access(TIS_ACCESS_ACTIVE_LOCALITY, locality); +} + +/* + * PC Client Specific TPM Interface Specification section 11.2.12: + * + * Software must be prepared to send two writes of a "1" to command ready + * field: the first to indicate successful read of all the data, thus + * clearing the data from the ReadFIFO and freeing the TPM's resources, + * and the second to indicate to the TPM it is about to send a new command. + * + * In practice not all TPMs behave the same so it is necessary to be + * flexible when trying to set command ready. + * + * Returns 0 on success if the TPM is ready for transactions. + * Returns TPM_TIMEOUT_ERR if the command ready bit does not get set. + */ +static int tis_command_ready(u8 locality) +{ + u32 status; + + /* 1st attempt to set command ready */ + tpm_write_status(TIS_STS_COMMAND_READY, locality); + + /* Wait for response */ + status = tpm_read_status(locality); + + /* Check if command ready is set yet */ + if (status & TIS_STS_COMMAND_READY) + return 0; + + /* 2nd attempt to set command ready */ + tpm_write_status(TIS_STS_COMMAND_READY, locality); + + return tis_wait_ready(locality); +} + +/* + * 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) +{ + const char *device_name = "unknown"; + const char *vendor_name = device_name; + const struct device_name *dev; + u32 didvid; + u16 vid, did; + int i; + + if (car_get_var(vendor_dev_id)) + return 0; /* Already probed. */ + + didvid = tpm_read_did_vid(0); + if (!didvid || (didvid == 0xffffffff)) { + printf("%s: No TPM device found\n", __FUNCTION__); + return TPM_DRIVER_ERR; + } + + car_set_var(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; + } else { + continue; + } + dev = &vendor_names[i].dev_names[j]; + while ((known_did = dev->dev_id) != 0xffff) { + if (known_did == did) { + device_name = dev->dev_name; + break; + } + j++; + } + break; + } + /* this will have to be converted into debug printout */ + printf("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; + + if (tis_wait_ready(locality)) { + printf("%s:%d - failed to get 'command_ready' status\n", + __FILE__, __LINE__); + return TPM_DRIVER_ERR; + } + burst = tpm_read_burst_count(locality); + + 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 = tpm_read_burst_count(locality); + } + + 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(data[offset++], locality); + + if (tis_wait_valid(locality) || !tis_expect_data(locality)) { + printf("%s:%d TPM command feed overflow\n", + __FILE__, __LINE__); + return TPM_DRIVER_ERR; + } + + burst = tpm_read_burst_count(locality); + 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(data[offset++], locality); + + /* + * Verify that TPM does not expect any more data as part of this + * command. + */ + if (tis_wait_valid(locality) || tis_expect_data(locality)) { + printf("%s:%d unexpected TPM status 0x%x\n", + __FILE__, __LINE__, tpm_read_status(locality)); + return TPM_DRIVER_ERR; + } + + /* OK, sitting pretty, let's start the command execution. */ + tpm_write_status(TIS_STS_TPM_GO, locality); + + 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 offset = 0; + u8 locality = 0; + u32 expected_count = *len; + int max_cycles = 0; + + /* Wait for the TPM to process the command */ + if (tis_wait_valid_data(locality)) { + printf("%s:%d failed processing command\n", __FILE__, __LINE__); + return TPM_DRIVER_ERR; + } + + do { + while ((burst_count = tpm_read_burst_count(locality)) == 0) { + if (max_cycles++ == MAX_DELAY_US) { + printf("%s:%d TPM stuck on read\n", + __FILE__, __LINE__); + return TPM_DRIVER_ERR; + } + udelay(1); + } + + max_cycles = 0; + + while (burst_count-- && (offset < expected_count)) { + buffer[offset++] = tpm_read_data(locality); + 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 */ + if (tis_wait_valid(locality)) { + 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 (tis_has_valid_data(locality)); + + /* * Make sure we indeed read all there was. */ + if (tis_has_valid_data(locality)) { + printf("%s:%d wrong receive status: %x %d bytes left\n", + __FILE__, __LINE__, tpm_read_status(locality), + tpm_read_burst_count(locality)); + return TPM_DRIVER_ERR; + } + + /* Tell the TPM that we are done. */ + if (tis_command_ready(locality) == TPM_TIMEOUT_ERR) + return TPM_DRIVER_ERR; + + *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 */ + tis_request_access(locality); + + /* did we get a lock? */ + if (tis_wait_received_access(locality)) { + printf("%s:%d - failed to lock locality %d\n", + __FILE__, __LINE__, locality); + return TPM_DRIVER_ERR; + } + + /* Certain TPMs seem to need some delay here or they hang... */ + udelay(10); + + if (tis_command_ready(locality) == TPM_TIMEOUT_ERR) + return TPM_DRIVER_ERR; + + return 0; +} + +/* + * tis_close() + * + * terminate the current 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 (tis_has_access(locality)) { + tis_drop_access(locality); + if (tis_wait_dropped_access(locality)) { + 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); +}