chip/g/board_id.c - chromiumos/platform/ec - Git at Google

 /* Copyright 2017 The ChromiumOS Authors
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */

 #include "common.h"
 #include "board_id.h"
 #include "endian.h"
 #include "extension.h"
 #include "flash_info.h"
 #include "system.h"
 #include "util.h"

 #define CPRINTS(format, args...) cprints(CC_SYSTEM, format, ## args)
 #define CPRINTF(format, args...) cprintf(CC_SYSTEM, format, ## args)

 #define BLANK_FIELD 0xffffffff

 /**
  * Return the image header for the current image copy
  */
 const struct SignedHeader *get_current_image_header(void)
 {
 	return (const struct SignedHeader *)
 			get_program_memory_addr(system_get_image_copy());
 }

 int board_id_type_is_blank(const struct board_id *id)
 {
 	return (id->type & id->type_inv) == BLANK_FIELD;
 }

 static int board_id_flags_are_blank(const struct board_id *id)
 {
 	return id->flags == BLANK_FIELD;
 }

 int board_id_is_blank(const struct board_id *id)
 {
 	return board_id_type_is_blank(id) && board_id_flags_are_blank(id);
 }

 int board_id_is_erased(void)
 {
 	struct board_id id;
 	/*
 	 * If we can't read the board id for some reason, return 0 just to be
 	 * safe
 	 */
 	if (read_board_id(&id) != EC_SUCCESS) {
 		CPRINTS("%s: BID read error", __func__);
 		return 0;
 	}

 	if (board_id_is_blank(&id)) {
 		CPRINTS("BID erased");
 		return 1;
 	}
 	return 0;
 }

 uint32_t check_board_id_vs_header(const struct board_id *id,
 				  const struct SignedHeader *h)
 {
 	uint32_t mismatch;
 	uint32_t header_board_id_type;
 	uint32_t header_board_id_mask;
 	uint32_t header_board_id_flags;

 	/* Blank Board ID matches all headers */
 	if (board_id_is_blank(id))
 		return 0;

 	header_board_id_type = SIGNED_HEADER_PADDING ^ h->board_id_type;
 	header_board_id_mask = SIGNED_HEADER_PADDING ^ h->board_id_type_mask;
 	header_board_id_flags = SIGNED_HEADER_PADDING ^ h->board_id_flags;

 	/*
 	 * All 1-bits in header Board ID flags must be present in flags from
 	 * flash
 	 */
 	mismatch =
 		((header_board_id_flags & id->flags) != header_board_id_flags);
 	/*
 	 * Masked bits in header Board ID type must match type and inverse from
 	 * flash.
 	 */
 	if (!mismatch && !board_id_type_is_blank(id)) {
 		mismatch = header_board_id_type ^ id->type;
 		mismatch |= header_board_id_type ^ ~id->type_inv;
 		mismatch &= header_board_id_mask;
 	}
 	return mismatch;
 }

 int read_board_id(struct board_id *id)
 {
 	uint32_t *id_p;
 	int i;

 	/*
 	 * Board ID structure size is guaranteed to be divisible by 4, and it
 	 * is guaranteed to be aligned at 4 bytes.
 	 */

 	id_p = (uint32_t *)id;

 	for (i = 0; i < sizeof(*id); i += sizeof(uint32_t)) {
 		int rv;

 		rv = flash_physical_info_read_word
 			(INFO_BOARD_ID_OFFSET + i, id_p);
 		if (rv != EC_SUCCESS) {
 			CPRINTF("%s: failed to read word %d, error %d\n",
 				__func__, i, rv);
 			return rv;
 		}
 		id_p++;
 	}
 	return EC_SUCCESS;
 }

 uint32_t board_id_mismatch(const struct SignedHeader *sh)
 {
 	struct board_id id;

 	if (!sh)
 		/* Get header of the currently running image. */
 		sh = get_current_image_header();

 	/* Get Board ID from INFO1. */
 	if (read_board_id(&id) != EC_SUCCESS) {
 		/*
 		 * On failure, set id fields to 0.  This will only match an
 		 * unrestricted image header (board_id_mask=board_id_flags=0),
 		 * which would run on any Board ID.
 		 *
 		 * Don't return error, because that would prevent all images
 		 * from running.
 		 */
 		id.type = id.type_inv = id.flags = 0;
 	}

 	return check_board_id_vs_header(&id, sh);
 }

 /**
  * Write board ID into the flash INFO1 space.
  *
  * @param id	Pointer to a Board ID structure to copy into INFO1
  *
  * @return EC_SUCCESS or an error code in cases of various failures to read or
  *              if the space has been already initialized.
  */
 static int write_board_id(struct board_id *id)
 {
 	struct board_id id_test;
 	uint32_t rv;

 	/* Fail if Board ID is already programmed */
 	rv = read_board_id(&id_test);
 	if (rv != EC_SUCCESS) {
 		CPRINTS("%s: error reading Board ID", __func__);
 		return rv;
 	}

 	if (!board_id_is_blank(&id_test)) {
 		if (!board_id_type_is_blank(&id_test)) {
 			CPRINTS("%s: Board ID already programmed", __func__);
 			return EC_ERROR_ACCESS_DENIED;
 		}
 		CPRINTS("%s: using old flags.", __func__);
 		id->flags = id_test.flags;
 	}

 	/*
 	 * Make sure the current header will still validate against the
 	 * proposed values.  If it doesn't, then programming these values
 	 * would cause the next boot to fail.
 	 */
 	if (check_board_id_vs_header(id, get_current_image_header()) != 0) {
 		CPRINTS("%s: Board ID wouldn't allow current header", __func__);
 		return EC_ERROR_INVAL;
 	}

 	flash_info_write_enable();

 	/* Write Board ID */
 	rv = flash_info_physical_write(INFO_BOARD_ID_OFFSET,
 				       sizeof(*id), (const char *)id);
 	if (rv != EC_SUCCESS)
 		CPRINTS("%s: write failed", __func__);

 	flash_info_write_disable();

 	return rv;
 }

 static enum vendor_cmd_rc vc_set_board_id(enum vendor_cmd_cc code,
 					  void *buf,
 					  size_t input_size,
 					  size_t *response_size)
 {
 	struct board_id id;
 	uint8_t *pbuf = buf;

 	*response_size = 1;

 	/* Exactly two fields are expected. */
 	if (input_size != sizeof(id.type) + sizeof(id.flags)) {
 		*pbuf = VENDOR_RC_BOGUS_ARGS;
 		return VENDOR_RC_BOGUS_ARGS;
 	}

 	memcpy(&id.type, pbuf, sizeof(id.type));
 	id.type = be32toh(id.type);
 	if (id.type == BLANK_FIELD)
 		id.type_inv = BLANK_FIELD;
 	else
 		id.type_inv = ~id.type;

 	memcpy(&id.flags, pbuf + sizeof(id.type), sizeof(id.flags));
 	id.flags = be32toh(id.flags);

 	/* We care about the LSB only. */
 	*pbuf = write_board_id(&id);

 	return *pbuf;
 }
 DECLARE_VENDOR_COMMAND(VENDOR_CC_SET_BOARD_ID, vc_set_board_id);

 static int command_board_id(int argc, char **argv)
 {
 	struct board_id id;
 	int rv = EC_ERROR_PARAM_COUNT;

 	if (argc == 1) {
 		rv = read_board_id(&id);

 		if (rv != EC_SUCCESS) {
 			ccprintf("Failed to read board ID space\n");
 			return rv;
 		}
 		ccprintf("Board ID: %08x:%08x, flags %08x\n", id.type,
 			 id.type_inv, id.flags);

 		if (board_id_is_blank(&id))
 			return rv; /* The space is not initialized. */

 		if (!board_id_type_is_blank(&id) && id.type != ~id.type_inv)
 			ccprintf("Inv Type Mismatch (%08x instead of %08x)!\n",
 				 id.type_inv, ~id.type);
 	}
 #ifdef CR50_DEV
 	else if (argc == 3) {
 		char *e;

 		id.type = strtoi(argv[1], &e, 0);
 		if (*e)
 			return EC_ERROR_PARAM1;
 		id.type_inv = ~id.type;
 		id.flags = strtoi(argv[2], &e, 0);
 		if (*e)
 			return EC_ERROR_PARAM2;
 		rv = write_board_id(&id);
 	}
 #endif
 	return rv;
 }
 DECLARE_SAFE_CONSOLE_COMMAND(bid, command_board_id,
 #ifdef CR50_DEV
 			     "[bid flags]",
 #else
 			     NULL,
 #endif
 			     "Set/Get Board ID");

 static enum vendor_cmd_rc vc_get_board_id(enum vendor_cmd_cc code,
 					  void *buf,
 					  size_t input_size,
 					  size_t *response_size)
 {
 	struct board_id id;

 	if (read_board_id(&id))
 		return VENDOR_RC_READ_FLASH_FAIL;

 	/* Convert to line representation. */
 	id.type = htobe32(id.type);
 	id.type_inv = htobe32(id.type_inv);
 	id.flags = htobe32(id.flags);

 	memcpy(buf, &id, sizeof(id));
 	*response_size = sizeof(id);

 	return VENDOR_RC_SUCCESS;
 }
 DECLARE_VENDOR_COMMAND(VENDOR_CC_GET_BOARD_ID, vc_get_board_id);
	/* Copyright 2017 The ChromiumOS Authors
	* Use of this source code is governed by a BSD-style license that can be
	* found in the LICENSE file.
	*/

	#include "common.h"
	#include "board_id.h"
	#include "endian.h"
	#include "extension.h"
	#include "flash_info.h"
	#include "system.h"
	#include "util.h"

	#define CPRINTS(format, args...) cprints(CC_SYSTEM, format, ## args)
	#define CPRINTF(format, args...) cprintf(CC_SYSTEM, format, ## args)

	#define BLANK_FIELD 0xffffffff

	/**
	* Return the image header for the current image copy
	*/
	const struct SignedHeader *get_current_image_header(void)
	{
	return (const struct SignedHeader *)
	get_program_memory_addr(system_get_image_copy());
	}

	int board_id_type_is_blank(const struct board_id *id)
	{
	return (id->type & id->type_inv) == BLANK_FIELD;
	}

	static int board_id_flags_are_blank(const struct board_id *id)
	{
	return id->flags == BLANK_FIELD;
	}

	int board_id_is_blank(const struct board_id *id)
	{
	return board_id_type_is_blank(id) && board_id_flags_are_blank(id);
	}

	int board_id_is_erased(void)
	{
	struct board_id id;
	/*
	* If we can't read the board id for some reason, return 0 just to be
	* safe
	*/
	if (read_board_id(&id) != EC_SUCCESS) {
	CPRINTS("%s: BID read error", __func__);
	return 0;
	}

	if (board_id_is_blank(&id)) {
	CPRINTS("BID erased");
	return 1;
	}
	return 0;
	}

	uint32_t check_board_id_vs_header(const struct board_id *id,
	const struct SignedHeader *h)
	{
	uint32_t mismatch;
	uint32_t header_board_id_type;
	uint32_t header_board_id_mask;
	uint32_t header_board_id_flags;

	/* Blank Board ID matches all headers */
	if (board_id_is_blank(id))
	return 0;

	header_board_id_type = SIGNED_HEADER_PADDING ^ h->board_id_type;
	header_board_id_mask = SIGNED_HEADER_PADDING ^ h->board_id_type_mask;
	header_board_id_flags = SIGNED_HEADER_PADDING ^ h->board_id_flags;

	/*
	* All 1-bits in header Board ID flags must be present in flags from
	* flash
	*/
	mismatch =
	((header_board_id_flags & id->flags) != header_board_id_flags);
	/*
	* Masked bits in header Board ID type must match type and inverse from
	* flash.
	*/
	if (!mismatch && !board_id_type_is_blank(id)) {
	mismatch = header_board_id_type ^ id->type;
	mismatch \|= header_board_id_type ^ ~id->type_inv;
	mismatch &= header_board_id_mask;
	}
	return mismatch;
	}

	int read_board_id(struct board_id *id)
	{
	uint32_t *id_p;
	int i;

	/*
	* Board ID structure size is guaranteed to be divisible by 4, and it
	* is guaranteed to be aligned at 4 bytes.
	*/

	id_p = (uint32_t *)id;

	for (i = 0; i < sizeof(*id); i += sizeof(uint32_t)) {
	int rv;

	rv = flash_physical_info_read_word
	(INFO_BOARD_ID_OFFSET + i, id_p);
	if (rv != EC_SUCCESS) {
	CPRINTF("%s: failed to read word %d, error %d\n",
	__func__, i, rv);
	return rv;
	}
	id_p++;
	}
	return EC_SUCCESS;
	}

	uint32_t board_id_mismatch(const struct SignedHeader *sh)
	{
	struct board_id id;

	if (!sh)
	/* Get header of the currently running image. */
	sh = get_current_image_header();

	/* Get Board ID from INFO1. */
	if (read_board_id(&id) != EC_SUCCESS) {
	/*
	* On failure, set id fields to 0. This will only match an
	* unrestricted image header (board_id_mask=board_id_flags=0),
	* which would run on any Board ID.
	*
	* Don't return error, because that would prevent all images
	* from running.
	*/
	id.type = id.type_inv = id.flags = 0;
	}

	return check_board_id_vs_header(&id, sh);
	}

	/**
	* Write board ID into the flash INFO1 space.
	*
	* @param id Pointer to a Board ID structure to copy into INFO1
	*
	* @return EC_SUCCESS or an error code in cases of various failures to read or
	* if the space has been already initialized.
	*/
	static int write_board_id(struct board_id *id)
	{
	struct board_id id_test;
	uint32_t rv;

	/* Fail if Board ID is already programmed */
	rv = read_board_id(&id_test);
	if (rv != EC_SUCCESS) {
	CPRINTS("%s: error reading Board ID", __func__);
	return rv;
	}

	if (!board_id_is_blank(&id_test)) {
	if (!board_id_type_is_blank(&id_test)) {
	CPRINTS("%s: Board ID already programmed", __func__);
	return EC_ERROR_ACCESS_DENIED;
	}
	CPRINTS("%s: using old flags.", __func__);
	id->flags = id_test.flags;
	}

	/*
	* Make sure the current header will still validate against the
	* proposed values. If it doesn't, then programming these values
	* would cause the next boot to fail.
	*/
	if (check_board_id_vs_header(id, get_current_image_header()) != 0) {
	CPRINTS("%s: Board ID wouldn't allow current header", __func__);
	return EC_ERROR_INVAL;
	}

	flash_info_write_enable();

	/* Write Board ID */
	rv = flash_info_physical_write(INFO_BOARD_ID_OFFSET,
	sizeof(id), (const char )id);
	if (rv != EC_SUCCESS)
	CPRINTS("%s: write failed", __func__);

	flash_info_write_disable();

	return rv;
	}

	static enum vendor_cmd_rc vc_set_board_id(enum vendor_cmd_cc code,
	void *buf,
	size_t input_size,
	size_t *response_size)
	{
	struct board_id id;
	uint8_t *pbuf = buf;

	*response_size = 1;

	/* Exactly two fields are expected. */
	if (input_size != sizeof(id.type) + sizeof(id.flags)) {
	*pbuf = VENDOR_RC_BOGUS_ARGS;
	return VENDOR_RC_BOGUS_ARGS;
	}

	memcpy(&id.type, pbuf, sizeof(id.type));
	id.type = be32toh(id.type);
	if (id.type == BLANK_FIELD)
	id.type_inv = BLANK_FIELD;
	else
	id.type_inv = ~id.type;

	memcpy(&id.flags, pbuf + sizeof(id.type), sizeof(id.flags));
	id.flags = be32toh(id.flags);

	/* We care about the LSB only. */
	*pbuf = write_board_id(&id);

	return *pbuf;
	}
	DECLARE_VENDOR_COMMAND(VENDOR_CC_SET_BOARD_ID, vc_set_board_id);

	static int command_board_id(int argc, char **argv)
	{
	struct board_id id;
	int rv = EC_ERROR_PARAM_COUNT;

	if (argc == 1) {
	rv = read_board_id(&id);

	if (rv != EC_SUCCESS) {
	ccprintf("Failed to read board ID space\n");
	return rv;
	}
	ccprintf("Board ID: %08x:%08x, flags %08x\n", id.type,
	id.type_inv, id.flags);

	if (board_id_is_blank(&id))
	return rv; /* The space is not initialized. */

	if (!board_id_type_is_blank(&id) && id.type != ~id.type_inv)
	ccprintf("Inv Type Mismatch (%08x instead of %08x)!\n",
	id.type_inv, ~id.type);
	}
	#ifdef CR50_DEV
	else if (argc == 3) {
	char *e;

	id.type = strtoi(argv[1], &e, 0);
	if (*e)
	return EC_ERROR_PARAM1;
	id.type_inv = ~id.type;
	id.flags = strtoi(argv[2], &e, 0);
	if (*e)
	return EC_ERROR_PARAM2;
	rv = write_board_id(&id);
	}
	#endif
	return rv;
	}
	DECLARE_SAFE_CONSOLE_COMMAND(bid, command_board_id,
	#ifdef CR50_DEV
	"[bid flags]",
	#else
	NULL,
	#endif
	"Set/Get Board ID");

	static enum vendor_cmd_rc vc_get_board_id(enum vendor_cmd_cc code,
	void *buf,
	size_t input_size,
	size_t *response_size)
	{
	struct board_id id;

	if (read_board_id(&id))
	return VENDOR_RC_READ_FLASH_FAIL;

	/* Convert to line representation. */
	id.type = htobe32(id.type);
	id.type_inv = htobe32(id.type_inv);
	id.flags = htobe32(id.flags);

	memcpy(buf, &id, sizeof(id));
	*response_size = sizeof(id);

	return VENDOR_RC_SUCCESS;
	}
	DECLARE_VENDOR_COMMAND(VENDOR_CC_GET_BOARD_ID, vc_get_board_id);