cbtable.c - chromiumos/third_party/flashrom - Git at Google

 /*
  * This file is part of the flashrom project.
  *
  * Copyright (C) 2002 Steven James <pyro@linuxlabs.com>
  * Copyright (C) 2002 Linux Networx
  * (Written by Eric Biederman <ebiederman@lnxi.com> for Linux Networx)
  * Copyright (C) 2006-2009 coresystems GmbH
  * (Written by Stefan Reinauer <stepan@coresystems.de> for coresystems GmbH)
  * Copyright (C) 2010 Carl-Daniel Hailfinger
  *
  * 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.
  *
  */

 #include <unistd.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include "flash.h"
 #include "programmer.h"
 #include "coreboot_tables.h"

 char *lb_part = NULL, *lb_vendor = NULL;
 int partvendor_from_cbtable = 0;

 /* Parse the [<vendor>:]<board> string specified by the user as part of
  * -p internal:mainboard=[<vendor>:]<board> and set lb_vendor and lb_part
  * to the extracted values.
  * Note: strtok modifies the original string, so we work on a copy and allocate
  * memory for lb_vendor and lb_part with strdup.
  */
 void lb_vendor_dev_from_string(const char *boardstring)
 {
 	/* strtok may modify the original string. */
 	char *tempstr = strdup(boardstring);
 	char *tempstr2 = NULL;
 	strtok(tempstr, ":");
 	tempstr2 = strtok(NULL, ":");
 	if (tempstr2) {
 		lb_vendor = strdup(tempstr);
 		lb_part = strdup(tempstr2);
 	} else {
 		lb_vendor = NULL;
 		lb_part = strdup(tempstr);
 	}
 	free(tempstr);
 }

 static unsigned long compute_checksum(void *addr, unsigned long length)
 {
 	uint8_t *ptr;
 	volatile union {
 		uint8_t byte[2];
 		uint16_t word;
 	} chksum;
 	unsigned long sum;
 	unsigned long i;

 	/* In the most straight forward way possible,
 	 * compute an ip style checksum.
 	 */
 	sum = 0;
 	ptr = addr;
 	for (i = 0; i < length; i++) {
 		unsigned long value;
 		value = ptr[i];
 		if (i & 1) {
 			value <<= 8;
 		}
 		/* Add the new value */
 		sum += value;
 		/* Wrap around the carry */
 		if (sum > 0xFFFF) {
 			sum = (sum + (sum >> 16)) & 0xFFFF;
 		}
 	}
 	chksum.byte[0] = sum & 0xff;
 	chksum.byte[1] = (sum >> 8) & 0xff;

 	return (~chksum.word) & 0xFFFF;
 }

 #define for_each_lbrec(head, rec) \
 	for(rec = (struct lb_record *)(((char *)head) + sizeof(*head)); \
 		(((char *)rec) < (((char *)head) + sizeof(*head) + head->table_bytes))  && \
 		(rec->size >= 1) && \
 		((((char *)rec) + rec->size) <= (((char *)head) + sizeof(*head) + head->table_bytes)); \
 		rec = (struct lb_record *)(((char *)rec) + rec->size))

 static int count_lb_records(struct lb_header *head)
 {
 	struct lb_record *rec;
 	int count;

 	count = 0;
 	for_each_lbrec(head, rec) {
 		count++;
 	}

 	return count;
 }

 static int lb_header_valid(struct lb_header *head, unsigned long addr)
 {
 	if (memcmp(head->signature, "LBIO", 4) != 0)
 		return 0;
 	msg_pdbg("Found candidate at: %08lx-%08lx\n",
 		     addr, addr + sizeof(*head) + head->table_bytes);
 	if (head->header_bytes != sizeof(*head)) {
 		msg_perr("Header bytes of %d are incorrect.\n",
 			head->header_bytes);
 		return 0;
 	}
 	if (compute_checksum((uint8_t *) head, sizeof(*head)) != 0) {
 		msg_perr("Bad header checksum.\n");
 		return 0;
 	}

 	return 1;
 }

 static int lb_table_valid(struct lb_header *head, struct lb_record *recs)
 {
 	if (compute_checksum(recs, head->table_bytes)
 	    != head->table_checksum) {
 		msg_perr("Bad table checksum: %04x.\n",
 			head->table_checksum);
 		return 0;
 	}
 	if (count_lb_records(head) != head->table_entries) {
 		msg_perr("Bad record count: %d.\n",
 			head->table_entries);
 		return 0;
 	}

 	return 1;
 }

 static struct lb_header *find_lb_table(void *base, unsigned long start,
 				       unsigned long end)
 {
 	unsigned long addr;

 	/* For now be stupid.... */
 	for (addr = start; addr < end; addr += 16) {
 		struct lb_header *head =
 		    (struct lb_header *)(((char *)base) + addr);
 		struct lb_record *recs =
 		    (struct lb_record *)(((char *)base) + addr + sizeof(*head));
 		if (!lb_header_valid(head, addr))
 			continue;
 		if (!lb_table_valid(head, recs))
 			continue;
 		msg_pdbg("Found coreboot table at 0x%08lx.\n", addr);
 		return head;

 	};

 	return NULL;
 }

 static struct lb_header *find_lb_table_remap(unsigned long start_addr,
 					     uint8_t **table_area)
 {
 	size_t offset;
 	unsigned long addr, end;
 	size_t mapping_size;
 	void *base;

 	mapping_size = getpagesize();
 	offset = start_addr % getpagesize();
 	start_addr -= offset;

 	base = physmap_try_ro("high tables", start_addr, mapping_size);
 	if (ERROR_PTR == base) {
 		msg_perr("Failed getting access to coreboot high tables.\n");
 		return NULL;
 	}

 	for (addr = offset, end = getpagesize(); addr < end; addr += 16) {
 		struct lb_record *recs;
 		struct lb_header *head;

 		/* No more headers to check. */
 		if (end - addr < sizeof(*head))
 			return NULL;

 		head = (struct lb_header *)(((char *)base) + addr);

 		if (!lb_header_valid(head, addr))
 			continue;

 		if (mapping_size - addr < head->table_bytes + sizeof(*head)) {
 			size_t prev_mapping_size = mapping_size;
 			mapping_size = head->table_bytes + sizeof(*head);
 			mapping_size += addr;
 			mapping_size += getpagesize() -
 				(mapping_size % getpagesize());
 			physunmap(base, prev_mapping_size);
 			base = physmap_try_ro("high tables", start_addr,
 						mapping_size);
 			if (ERROR_PTR == base) {
 				msg_perr("Failed getting access to coreboot high tables.\n");
 				return NULL;
 			}
 		}

 		head = (struct lb_header *)(((char *)base) + addr);
 		recs =
 		    (struct lb_record *)(((char *)base) + addr + sizeof(*head));
 		if (!lb_table_valid(head, recs))
 			continue;
 		msg_pdbg("Found coreboot table at 0x%08lx.\n", addr);
 		*table_area = base;
 		return head;
 	}

 	physunmap(base, mapping_size);
 	return NULL;
 }

 static void find_mainboard(struct lb_record *ptr, unsigned long addr)
 {
 	struct lb_mainboard *rec;
 	int max_size;
 	char vendor[256], part[256];

 	rec = (struct lb_mainboard *)ptr;
 	max_size = rec->size - sizeof(*rec);
 	msg_pdbg("Vendor ID: %.*s, part ID: %.*s\n",
 	         max_size - rec->vendor_idx,
 	         rec->strings + rec->vendor_idx,
 	         max_size - rec->part_number_idx,
 	         rec->strings + rec->part_number_idx);
 	snprintf(vendor, 255, "%.*s", max_size - rec->vendor_idx, rec->strings + rec->vendor_idx);
 	snprintf(part, 255, "%.*s", max_size - rec->part_number_idx, rec->strings + rec->part_number_idx);

 	if (lb_part) {
 		msg_pdbg("Overwritten by command line, vendor ID: %s, part ID: %s.\n", lb_vendor, lb_part);
 	} else {
 		partvendor_from_cbtable = 1;
 		lb_part = strdup(part);
 		lb_vendor = strdup(vendor);
 	}
 }

 static struct lb_record *next_record(struct lb_record *rec)
 {
 	return (struct lb_record *)(((char *)rec) + rec->size);
 }

 static void search_lb_records(struct lb_record *rec, struct lb_record *last, unsigned long addr)
 {
 	struct lb_record *next;
 	int count;
 	count = 0;

 	for (next = next_record(rec); (rec < last) && (next <= last);
 	     rec = next, addr += rec->size) {
 		next = next_record(rec);
 		count++;
 		if (rec->tag == LB_TAG_MAINBOARD) {
 			find_mainboard(rec, addr);
 			break;
 		}
 	}
 }

 #define BYTES_TO_MAP (1024*1024)
 int coreboot_init(void)
 {
 	uint8_t *table_area;
 	unsigned long addr, start;
 	struct lb_header *lb_table;
 	struct lb_record *rec, *last;

 #if defined(__MACH__) && defined(__APPLE__)
 	/* This is a hack. DirectHW fails to map physical address 0x00000000.
 	 * Why?
 	 */
 	start = 0x400;
 #else
 	start = 0x0;
 #endif
 	table_area = physmap_try_ro("low megabyte", start, BYTES_TO_MAP - start);
 	if (ERROR_PTR == table_area) {
 		msg_perr("Failed getting access to coreboot low tables.\n");
 		return -1;
 	}

 	lb_table = find_lb_table(table_area, 0x00000, 0x1000);
 	if (!lb_table)
 		lb_table = find_lb_table(table_area, 0xf0000 - start, BYTES_TO_MAP - start);
 	if (lb_table) {
 		struct lb_forward *forward = (struct lb_forward *)
 			(((char *)lb_table) + lb_table->header_bytes);
 		if (forward->tag == LB_TAG_FORWARD) {
 			start = forward->forward;
 			physunmap(table_area, BYTES_TO_MAP);
 			lb_table = find_lb_table_remap(start, &table_area);
 		}
 	}

 	if (!lb_table) {
 		msg_pdbg("No coreboot table found.\n");
 		return -1;
 	}

 	addr = ((char *)lb_table) - ((char *)table_area) + start;
 	msg_pinfo("coreboot table found at 0x%lx.\n",
 		(unsigned long)lb_table - (unsigned long)table_area + start);
 	rec = (struct lb_record *)(((char *)lb_table) + lb_table->header_bytes);
 	last = (struct lb_record *)(((char *)rec) + lb_table->table_bytes);
 	msg_pdbg("coreboot header(%d) checksum: %04x table(%d) checksum: %04x entries: %d\n",
 	     lb_table->header_bytes, lb_table->header_checksum,
 	     lb_table->table_bytes, lb_table->table_checksum,
 	     lb_table->table_entries);
 	search_lb_records(rec, last, addr + lb_table->header_bytes);

 	return 0;
 }
	/*
	* This file is part of the flashrom project.
	*
	* Copyright (C) 2002 Steven James <pyro@linuxlabs.com>
	* Copyright (C) 2002 Linux Networx
	* (Written by Eric Biederman <ebiederman@lnxi.com> for Linux Networx)
	* Copyright (C) 2006-2009 coresystems GmbH
	* (Written by Stefan Reinauer <stepan@coresystems.de> for coresystems GmbH)
	* Copyright (C) 2010 Carl-Daniel Hailfinger
	*
	* 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.
	*
	*/

	#include <unistd.h>
	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include "flash.h"
	#include "programmer.h"
	#include "coreboot_tables.h"

	char lb_part = NULL, lb_vendor = NULL;
	int partvendor_from_cbtable = 0;

	/* Parse the [<vendor>:]<board> string specified by the user as part of
	* -p internal:mainboard=[<vendor>:]<board> and set lb_vendor and lb_part
	* to the extracted values.
	* Note: strtok modifies the original string, so we work on a copy and allocate
	* memory for lb_vendor and lb_part with strdup.
	*/
	void lb_vendor_dev_from_string(const char *boardstring)
	{
	/* strtok may modify the original string. */
	char *tempstr = strdup(boardstring);
	char *tempstr2 = NULL;
	strtok(tempstr, ":");
	tempstr2 = strtok(NULL, ":");
	if (tempstr2) {
	lb_vendor = strdup(tempstr);
	lb_part = strdup(tempstr2);
	} else {
	lb_vendor = NULL;
	lb_part = strdup(tempstr);
	}
	free(tempstr);
	}

	static unsigned long compute_checksum(void *addr, unsigned long length)
	{
	uint8_t *ptr;
	volatile union {
	uint8_t byte[2];
	uint16_t word;
	} chksum;
	unsigned long sum;
	unsigned long i;

	/* In the most straight forward way possible,
	* compute an ip style checksum.
	*/
	sum = 0;
	ptr = addr;
	for (i = 0; i < length; i++) {
	unsigned long value;
	value = ptr[i];
	if (i & 1) {
	value <<= 8;
	}
	/* Add the new value */
	sum += value;
	/* Wrap around the carry */
	if (sum > 0xFFFF) {
	sum = (sum + (sum >> 16)) & 0xFFFF;
	}
	}
	chksum.byte[0] = sum & 0xff;
	chksum.byte[1] = (sum >> 8) & 0xff;

	return (~chksum.word) & 0xFFFF;
	}

	#define for_each_lbrec(head, rec) \
	for(rec = (struct lb_record )(((char )head) + sizeof(*head)); \
	(((char )rec) < (((char )head) + sizeof(*head) + head->table_bytes)) && \
	(rec->size >= 1) && \
	((((char )rec) + rec->size) <= (((char )head) + sizeof(*head) + head->table_bytes)); \
	rec = (struct lb_record )(((char )rec) + rec->size))

	static int count_lb_records(struct lb_header *head)
	{
	struct lb_record *rec;
	int count;

	count = 0;
	for_each_lbrec(head, rec) {
	count++;
	}

	return count;
	}

	static int lb_header_valid(struct lb_header *head, unsigned long addr)
	{
	if (memcmp(head->signature, "LBIO", 4) != 0)
	return 0;
	msg_pdbg("Found candidate at: %08lx-%08lx\n",
	addr, addr + sizeof(*head) + head->table_bytes);
	if (head->header_bytes != sizeof(*head)) {
	msg_perr("Header bytes of %d are incorrect.\n",
	head->header_bytes);
	return 0;
	}
	if (compute_checksum((uint8_t ) head, sizeof(head)) != 0) {
	msg_perr("Bad header checksum.\n");
	return 0;
	}

	return 1;
	}

	static int lb_table_valid(struct lb_header head, struct lb_record recs)
	{
	if (compute_checksum(recs, head->table_bytes)
	!= head->table_checksum) {
	msg_perr("Bad table checksum: %04x.\n",
	head->table_checksum);
	return 0;
	}
	if (count_lb_records(head) != head->table_entries) {
	msg_perr("Bad record count: %d.\n",
	head->table_entries);
	return 0;
	}

	return 1;
	}

	static struct lb_header find_lb_table(void base, unsigned long start,
	unsigned long end)
	{
	unsigned long addr;

	/* For now be stupid.... */
	for (addr = start; addr < end; addr += 16) {
	struct lb_header *head =
	(struct lb_header )(((char )base) + addr);
	struct lb_record *recs =
	(struct lb_record )(((char )base) + addr + sizeof(*head));
	if (!lb_header_valid(head, addr))
	continue;
	if (!lb_table_valid(head, recs))
	continue;
	msg_pdbg("Found coreboot table at 0x%08lx.\n", addr);
	return head;

	};

	return NULL;
	}

	static struct lb_header *find_lb_table_remap(unsigned long start_addr,
	uint8_t **table_area)
	{
	size_t offset;
	unsigned long addr, end;
	size_t mapping_size;
	void *base;

	mapping_size = getpagesize();
	offset = start_addr % getpagesize();
	start_addr -= offset;

	base = physmap_try_ro("high tables", start_addr, mapping_size);
	if (ERROR_PTR == base) {
	msg_perr("Failed getting access to coreboot high tables.\n");
	return NULL;
	}

	for (addr = offset, end = getpagesize(); addr < end; addr += 16) {
	struct lb_record *recs;
	struct lb_header *head;

	/* No more headers to check. */
	if (end - addr < sizeof(*head))
	return NULL;

	head = (struct lb_header )(((char )base) + addr);

	if (!lb_header_valid(head, addr))
	continue;

	if (mapping_size - addr < head->table_bytes + sizeof(*head)) {
	size_t prev_mapping_size = mapping_size;
	mapping_size = head->table_bytes + sizeof(*head);
	mapping_size += addr;
	mapping_size += getpagesize() -
	(mapping_size % getpagesize());
	physunmap(base, prev_mapping_size);
	base = physmap_try_ro("high tables", start_addr,
	mapping_size);
	if (ERROR_PTR == base) {
	msg_perr("Failed getting access to coreboot high tables.\n");
	return NULL;
	}
	}

	head = (struct lb_header )(((char )base) + addr);
	recs =
	(struct lb_record )(((char )base) + addr + sizeof(*head));
	if (!lb_table_valid(head, recs))
	continue;
	msg_pdbg("Found coreboot table at 0x%08lx.\n", addr);
	*table_area = base;
	return head;
	}

	physunmap(base, mapping_size);
	return NULL;
	}

	static void find_mainboard(struct lb_record *ptr, unsigned long addr)
	{
	struct lb_mainboard *rec;
	int max_size;
	char vendor[256], part[256];

	rec = (struct lb_mainboard *)ptr;
	max_size = rec->size - sizeof(*rec);
	msg_pdbg("Vendor ID: %.s, part ID: %.s\n",
	max_size - rec->vendor_idx,
	rec->strings + rec->vendor_idx,
	max_size - rec->part_number_idx,
	rec->strings + rec->part_number_idx);
	snprintf(vendor, 255, "%.*s", max_size - rec->vendor_idx, rec->strings + rec->vendor_idx);
	snprintf(part, 255, "%.*s", max_size - rec->part_number_idx, rec->strings + rec->part_number_idx);

	if (lb_part) {
	msg_pdbg("Overwritten by command line, vendor ID: %s, part ID: %s.\n", lb_vendor, lb_part);
	} else {
	partvendor_from_cbtable = 1;
	lb_part = strdup(part);
	lb_vendor = strdup(vendor);
	}
	}

	static struct lb_record next_record(struct lb_record rec)
	{
	return (struct lb_record )(((char )rec) + rec->size);
	}

	static void search_lb_records(struct lb_record rec, struct lb_record last, unsigned long addr)
	{
	struct lb_record *next;
	int count;
	count = 0;

	for (next = next_record(rec); (rec < last) && (next <= last);
	rec = next, addr += rec->size) {
	next = next_record(rec);
	count++;
	if (rec->tag == LB_TAG_MAINBOARD) {
	find_mainboard(rec, addr);
	break;
	}
	}
	}

	#define BYTES_TO_MAP (1024*1024)
	int coreboot_init(void)
	{
	uint8_t *table_area;
	unsigned long addr, start;
	struct lb_header *lb_table;
	struct lb_record rec, last;

	#if defined(__MACH__) && defined(__APPLE__)
	/* This is a hack. DirectHW fails to map physical address 0x00000000.
	* Why?
	*/
	start = 0x400;
	#else
	start = 0x0;
	#endif
	table_area = physmap_try_ro("low megabyte", start, BYTES_TO_MAP - start);
	if (ERROR_PTR == table_area) {
	msg_perr("Failed getting access to coreboot low tables.\n");
	return -1;
	}

	lb_table = find_lb_table(table_area, 0x00000, 0x1000);
	if (!lb_table)
	lb_table = find_lb_table(table_area, 0xf0000 - start, BYTES_TO_MAP - start);
	if (lb_table) {
	struct lb_forward forward = (struct lb_forward )
	(((char *)lb_table) + lb_table->header_bytes);
	if (forward->tag == LB_TAG_FORWARD) {
	start = forward->forward;
	physunmap(table_area, BYTES_TO_MAP);
	lb_table = find_lb_table_remap(start, &table_area);
	}
	}

	if (!lb_table) {
	msg_pdbg("No coreboot table found.\n");
	return -1;
	}

	addr = ((char )lb_table) - ((char )table_area) + start;
	msg_pinfo("coreboot table found at 0x%lx.\n",
	(unsigned long)lb_table - (unsigned long)table_area + start);
	rec = (struct lb_record )(((char )lb_table) + lb_table->header_bytes);
	last = (struct lb_record )(((char )rec) + lb_table->table_bytes);
	msg_pdbg("coreboot header(%d) checksum: %04x table(%d) checksum: %04x entries: %d\n",
	lb_table->header_bytes, lb_table->header_checksum,
	lb_table->table_bytes, lb_table->table_checksum,
	lb_table->table_entries);
	search_lb_records(rec, last, addr + lb_table->header_bytes);

	return 0;
	}