a73b93157f
It encourages users from writing to the FSF without giving an address. Linux also prefers to drop that and their checkpatch.pl (that we imported) looks out for that. This is the result of util/scripts/no-fsf-addresses.sh with no further editing. Change-Id: Ie96faea295fe001911d77dbc51e9a6789558fbd6 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Reviewed-on: http://review.coreboot.org/11888 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com> Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
605 lines
18 KiB
C
605 lines
18 KiB
C
/*****************************************************************************\
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* lbtable.c
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*****************************************************************************
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* Copyright (C) 2012, Vikram Narayanan
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* Unified build_opt_tbl and nvramtool
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* build_opt_tbl.c
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* Copyright (C) 2003 Eric Biederman (ebiederm@xmission.com)
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* Copyright (C) 2007-2010 coresystems GmbH
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*
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* Copyright (C) 2002-2005 The Regents of the University of California.
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* Produced at the Lawrence Livermore National Laboratory.
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* Written by Dave Peterson <dsp@llnl.gov> <dave_peterson@pobox.com>
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* and Stefan Reinauer <stepan@openbios.org>.
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* UCRL-CODE-2003-012
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* All rights reserved.
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*
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* This file is part of nvramtool, a utility for reading/writing coreboot
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* parameters and displaying information from the coreboot table.
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* For details, see http://coreboot.org/nvramtool.
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*
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* Please also read the file DISCLAIMER which is included in this software
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* distribution.
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License (as published by the
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* Free Software Foundation) version 2, dated June 1991.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the IMPLIED WARRANTY OF
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the terms and
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* conditions of the GNU General Public License for more details.
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\*****************************************************************************/
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#include <string.h>
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#ifndef __MINGW32__
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#include <sys/mman.h>
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#endif
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#include "common.h"
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#include "coreboot_tables.h"
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#include "ip_checksum.h"
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#include "lbtable.h"
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#include "layout.h"
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#include "cmos_lowlevel.h"
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#include "hexdump.h"
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#include "cbfs.h"
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#include "layout-text.h"
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static void process_cmos_table(void);
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static void get_cmos_checksum_info(void);
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static void try_convert_checksum_layout(cmos_checksum_layout_t * layout);
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static void try_add_cmos_table_enum(cmos_enum_t * cmos_enum);
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static void try_add_cmos_table_entry(cmos_entry_t * cmos_entry);
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static const struct cmos_entries *first_cmos_table_entry(void);
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static const struct cmos_entries *next_cmos_table_entry(const struct
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cmos_entries *last);
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static const struct cmos_enums *first_cmos_table_enum(void);
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static const struct cmos_enums *next_cmos_table_enum
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(const struct cmos_enums *last);
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static const struct lb_record *first_cmos_rec(uint32_t tag);
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static const struct lb_record *next_cmos_rec(const struct lb_record *last,
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uint32_t tag);
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/* The CMOS option table is located within the coreboot table. It tells us
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* where the CMOS parameters are located in the nonvolatile RAM.
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*/
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static const struct cmos_option_table *cmos_table = NULL;
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#define ROUNDUP4(x) (x += (4 - (x % 4)))
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void process_layout(void)
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{
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if ((cmos_table) == NULL) {
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fprintf(stderr,
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"%s: CMOS option table not found in coreboot table. "
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"Apparently, the coreboot installed on this system was "
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"built without specifying CONFIG_HAVE_OPTION_TABLE.\n",
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prog_name);
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exit(1);
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}
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process_cmos_table();
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get_cmos_checksum_info();
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}
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void get_layout_from_cbfs_file(void)
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{
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uint32_t len;
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cmos_table = cbfs_find_file("cmos_layout.bin", CBFS_COMPONENT_CMOS_LAYOUT, &len);
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process_layout();
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}
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int write_cmos_layout_bin(FILE *f)
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{
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const cmos_entry_t *cmos_entry;
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const cmos_enum_t *cmos_enum;
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cmos_checksum_layout_t layout;
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struct cmos_option_table table;
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struct cmos_entries entry;
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struct cmos_enums cenum;
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struct cmos_checksum csum;
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size_t sum = 0;
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int len;
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for (cmos_entry = first_cmos_entry(); cmos_entry != NULL;
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cmos_entry = next_cmos_entry(cmos_entry)) {
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if (cmos_entry == first_cmos_entry()) {
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sum += sizeof(table);
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table.header_length = sizeof(table);
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table.tag = LB_TAG_CMOS_OPTION_TABLE;
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table.size = 0;
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if (fwrite((char *)&table, sizeof(table), 1, f) != 1) {
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perror("Error writing image file");
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goto err;
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}
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}
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memset(&entry, 0, sizeof(entry));
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entry.tag = LB_TAG_OPTION;
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entry.config = cmos_entry->config;
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entry.config_id = (uint32_t)cmos_entry->config_id;
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entry.bit = cmos_entry->bit;
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entry.length = cmos_entry->length;
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if (!is_ident((char *)cmos_entry->name)) {
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fprintf(stderr,
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"Error - Name %s is an invalid identifier\n",
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cmos_entry->name);
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goto err;
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}
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memcpy(entry.name, cmos_entry->name, strlen(cmos_entry->name));
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entry.name[strlen(cmos_entry->name)] = '\0';
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len = strlen(cmos_entry->name) + 1;
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if (len % 4)
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ROUNDUP4(len);
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entry.size = sizeof(entry) - CMOS_MAX_NAME_LENGTH + len;
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sum += entry.size;
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if (fwrite((char *)&entry, entry.size, 1, f) != 1) {
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perror("Error writing image file");
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goto err;
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}
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}
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for (cmos_enum = first_cmos_enum();
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cmos_enum != NULL; cmos_enum = next_cmos_enum(cmos_enum)) {
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memset(&cenum, 0, sizeof(cenum));
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cenum.tag = LB_TAG_OPTION_ENUM;
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memcpy(cenum.text, cmos_enum->text, strlen(cmos_enum->text));
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cenum.text[strlen(cmos_enum->text)] = '\0';
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len = strlen((char *)cenum.text) + 1;
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if (len % 4)
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ROUNDUP4(len);
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cenum.config_id = cmos_enum->config_id;
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cenum.value = cmos_enum->value;
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cenum.size = sizeof(cenum) - CMOS_MAX_TEXT_LENGTH + len;
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sum += cenum.size;
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if (fwrite((char *)&cenum, cenum.size, 1, f) != 1) {
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perror("Error writing image file");
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goto err;
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}
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}
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layout.summed_area_start = cmos_checksum_start;
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layout.summed_area_end = cmos_checksum_end;
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layout.checksum_at = cmos_checksum_index;
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checksum_layout_to_bits(&layout);
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csum.tag = LB_TAG_OPTION_CHECKSUM;
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csum.size = sizeof(csum);
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csum.range_start = layout.summed_area_start;
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csum.range_end = layout.summed_area_end;
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csum.location = layout.checksum_at;
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csum.type = CHECKSUM_PCBIOS;
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sum += csum.size;
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if (fwrite((char *)&csum, csum.size, 1, f) != 1) {
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perror("Error writing image file");
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goto err;
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}
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if (fseek(f, 0, SEEK_SET) != 0) {
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perror("Error while seeking");
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goto err;
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}
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table.size = sum;
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if (fwrite((char *)&table, sizeof(table), 1, f) != 1) {
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perror("Error writing image file");
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goto err;
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}
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return sum;
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err:
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fclose(f);
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exit(1);
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}
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void write_cmos_output_bin(const char *binary_filename)
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{
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FILE *fp;
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if ((fp = fopen(binary_filename, "wb")) == NULL) {
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fprintf(stderr,
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"%s: Can not open file %s for writing: "
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"%s\n", prog_name, binary_filename, strerror(errno));
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exit(1);
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}
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write_cmos_layout_bin(fp);
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fclose(fp);
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}
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/****************************************************************************
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* get_layout_from_cmos_table
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*
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* Find the CMOS table which is stored within the coreboot table and set the
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* global variable cmos_table to point to it.
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****************************************************************************/
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void get_layout_from_cmos_table(void)
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{
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get_lbtable();
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cmos_table = (const struct cmos_option_table *)
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find_lbrec(LB_TAG_CMOS_OPTION_TABLE);
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process_layout();
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}
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/****************************************************************************
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* process_cmos_table
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*
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* Extract layout information from the CMOS option table and store it in our
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* internal repository.
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****************************************************************************/
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static void process_cmos_table(void)
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{
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const struct cmos_enums *p;
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const struct cmos_entries *q;
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cmos_enum_t cmos_enum;
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cmos_entry_t cmos_entry;
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/* First add the enums. */
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for (p = first_cmos_table_enum(); p != NULL;
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p = next_cmos_table_enum(p)) {
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cmos_enum.config_id = p->config_id;
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cmos_enum.value = p->value;
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strncpy(cmos_enum.text, (char *)p->text, CMOS_MAX_TEXT_LENGTH);
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cmos_enum.text[CMOS_MAX_TEXT_LENGTH] = '\0';
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try_add_cmos_table_enum(&cmos_enum);
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}
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/* Now add the entries. We must add the entries after the enums because
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* the entries are sanity checked against the enums as they are added.
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*/
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for (q = first_cmos_table_entry(); q != NULL;
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q = next_cmos_table_entry(q)) {
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cmos_entry.bit = q->bit;
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cmos_entry.length = q->length;
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switch (q->config) {
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case 'e':
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cmos_entry.config = CMOS_ENTRY_ENUM;
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break;
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case 'h':
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cmos_entry.config = CMOS_ENTRY_HEX;
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break;
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case 'r':
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cmos_entry.config = CMOS_ENTRY_RESERVED;
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break;
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case 's':
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cmos_entry.config = CMOS_ENTRY_STRING;
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break;
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default:
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fprintf(stderr,
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"%s: Entry in CMOS option table has unknown config "
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"value.\n", prog_name);
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exit(1);
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}
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cmos_entry.config_id = q->config_id;
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strncpy(cmos_entry.name, (char *)q->name, CMOS_MAX_NAME_LENGTH);
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cmos_entry.name[CMOS_MAX_NAME_LENGTH] = '\0';
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try_add_cmos_table_entry(&cmos_entry);
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}
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}
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/****************************************************************************
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* get_cmos_checksum_info
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*
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* Get layout information for CMOS checksum.
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****************************************************************************/
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static void get_cmos_checksum_info(void)
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{
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const cmos_entry_t *e;
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struct cmos_checksum *checksum;
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cmos_checksum_layout_t layout;
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unsigned index, index2;
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checksum = (struct cmos_checksum *)next_cmos_rec((const struct lb_record *)first_cmos_table_enum(), LB_TAG_OPTION_CHECKSUM);
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if (checksum != NULL) { /* We are lucky. The coreboot table hints us to the checksum.
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* We might have to check the type field here though.
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*/
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layout.summed_area_start = checksum->range_start;
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layout.summed_area_end = checksum->range_end;
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layout.checksum_at = checksum->location;
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try_convert_checksum_layout(&layout);
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cmos_checksum_start = layout.summed_area_start;
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cmos_checksum_end = layout.summed_area_end;
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cmos_checksum_index = layout.checksum_at;
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return;
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}
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if ((e = find_cmos_entry(checksum_param_name)) == NULL)
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return;
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/* If we get here, we are unlucky. The CMOS option table contains the
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* location of the CMOS checksum. However, there is no information
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* regarding which bytes of the CMOS area the checksum is computed over.
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* Thus we have to hope our presets will be fine.
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*/
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if (e->bit % 8) {
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fprintf(stderr,
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"%s: Error: CMOS checksum is not byte-aligned.\n",
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prog_name);
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exit(1);
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}
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index = e->bit / 8;
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index2 = index + 1; /* The CMOS checksum occupies 16 bits. */
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if (verify_cmos_byte_index(index) || verify_cmos_byte_index(index2)) {
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fprintf(stderr,
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"%s: Error: CMOS checksum location out of range.\n",
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prog_name);
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exit(1);
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}
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if (((index >= cmos_checksum_start) && (index <= cmos_checksum_end)) ||
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(((index2) >= cmos_checksum_start)
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&& ((index2) <= cmos_checksum_end))) {
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fprintf(stderr,
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"%s: Error: CMOS checksum overlaps checksummed area.\n",
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prog_name);
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exit(1);
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}
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cmos_checksum_index = index;
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}
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/****************************************************************************
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* try_convert_checksum_layout
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*
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* Perform sanity checking on CMOS checksum layout information and attempt to
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* convert information from bit positions to byte positions. Return OK on
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* success or an error code on failure.
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****************************************************************************/
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static void try_convert_checksum_layout(cmos_checksum_layout_t * layout)
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{
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switch (checksum_layout_to_bytes(layout)) {
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case OK:
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return;
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case LAYOUT_SUMMED_AREA_START_NOT_ALIGNED:
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fprintf(stderr,
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"%s: CMOS checksummed area start is not byte-aligned.\n",
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prog_name);
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break;
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case LAYOUT_SUMMED_AREA_END_NOT_ALIGNED:
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fprintf(stderr,
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"%s: CMOS checksummed area end is not byte-aligned.\n",
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prog_name);
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break;
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case LAYOUT_CHECKSUM_LOCATION_NOT_ALIGNED:
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fprintf(stderr,
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"%s: CMOS checksum location is not byte-aligned.\n",
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prog_name);
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break;
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case LAYOUT_INVALID_SUMMED_AREA:
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fprintf(stderr,
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"%s: CMOS checksummed area end must be greater than "
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"CMOS checksummed area start.\n", prog_name);
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break;
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case LAYOUT_CHECKSUM_OVERLAPS_SUMMED_AREA:
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fprintf(stderr,
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"%s: CMOS checksum overlaps checksummed area.\n",
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prog_name);
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break;
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case LAYOUT_SUMMED_AREA_OUT_OF_RANGE:
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fprintf(stderr,
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"%s: CMOS checksummed area out of range.\n", prog_name);
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break;
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case LAYOUT_CHECKSUM_LOCATION_OUT_OF_RANGE:
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fprintf(stderr,
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"%s: CMOS checksum location out of range.\n",
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prog_name);
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break;
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default:
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BUG();
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}
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exit(1);
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}
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/****************************************************************************
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* try_add_cmos_table_enum
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*
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* Attempt to add a CMOS enum to our internal repository. Exit with an error
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* message on failure.
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****************************************************************************/
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static void try_add_cmos_table_enum(cmos_enum_t * cmos_enum)
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{
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switch (add_cmos_enum(cmos_enum)) {
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case OK:
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return;
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case LAYOUT_DUPLICATE_ENUM:
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fprintf(stderr, "%s: Duplicate enum %s found in CMOS option "
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"table.\n", prog_name, cmos_enum->text);
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break;
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default:
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BUG();
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}
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exit(1);
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}
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/****************************************************************************
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* try_add_cmos_table_entry
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*
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* Attempt to add a CMOS entry to our internal repository. Exit with an
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* error message on failure.
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****************************************************************************/
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static void try_add_cmos_table_entry(cmos_entry_t * cmos_entry)
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{
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const cmos_entry_t *conflict;
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switch (add_cmos_entry(cmos_entry, &conflict)) {
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case OK:
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return;
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case CMOS_AREA_OUT_OF_RANGE:
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fprintf(stderr,
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"%s: Bad CMOS option layout in CMOS option table entry "
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"%s.\n", prog_name, cmos_entry->name);
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break;
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case CMOS_AREA_TOO_WIDE:
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fprintf(stderr,
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"%s: Area too wide for CMOS option table entry %s.\n",
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prog_name, cmos_entry->name);
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break;
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case LAYOUT_ENTRY_OVERLAP:
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fprintf(stderr,
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"%s: CMOS option table entries %s and %s have overlapping "
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"layouts.\n", prog_name, cmos_entry->name,
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conflict->name);
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break;
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case LAYOUT_ENTRY_BAD_LENGTH:
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/* Silently ignore entries with zero length. Although this should
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* never happen in practice, we should handle the case in a
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* reasonable manner just to be safe.
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*/
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return;
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default:
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BUG();
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}
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exit(1);
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}
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/****************************************************************************
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* first_cmos_table_entry
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*
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* Return a pointer to the first entry in the CMOS table that represents a
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* CMOS parameter. Return NULL if CMOS table is empty.
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****************************************************************************/
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static const struct cmos_entries *first_cmos_table_entry(void)
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{
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return (const struct cmos_entries *)first_cmos_rec(LB_TAG_OPTION);
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}
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/****************************************************************************
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* next_cmos_table_entry
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*
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* Return a pointer to the next entry after 'last' in the CMOS table that
|
|
* represents a CMOS parameter. Return NULL if there are no more parameters.
|
|
****************************************************************************/
|
|
static const struct cmos_entries *next_cmos_table_entry(const struct
|
|
cmos_entries *last)
|
|
{
|
|
return (const struct cmos_entries *)
|
|
next_cmos_rec((const struct lb_record *)last, LB_TAG_OPTION);
|
|
}
|
|
|
|
/****************************************************************************
|
|
* first_cmos_table_enum
|
|
*
|
|
* Return a pointer to the first entry in the CMOS table that represents a
|
|
* possible CMOS parameter value. Return NULL if the table does not contain
|
|
* any such entries.
|
|
****************************************************************************/
|
|
static const struct cmos_enums *first_cmos_table_enum(void)
|
|
{
|
|
return (const struct cmos_enums *)first_cmos_rec(LB_TAG_OPTION_ENUM);
|
|
}
|
|
|
|
/****************************************************************************
|
|
* next_cmos_table_enum
|
|
*
|
|
* Return a pointer to the next entry after 'last' in the CMOS table that
|
|
* represents a possible CMOS parameter value. Return NULL if there are no
|
|
* more parameter values.
|
|
****************************************************************************/
|
|
static const struct cmos_enums *next_cmos_table_enum
|
|
(const struct cmos_enums *last) {
|
|
return (const struct cmos_enums *)
|
|
next_cmos_rec((const struct lb_record *)last, LB_TAG_OPTION_ENUM);
|
|
}
|
|
|
|
/****************************************************************************
|
|
* first_cmos_rec
|
|
*
|
|
* Return a pointer to the first entry in the CMOS table whose type matches
|
|
* 'tag'. Return NULL if CMOS table contains no such entry.
|
|
*
|
|
* Possible values for 'tag' are as follows:
|
|
*
|
|
* LB_TAG_OPTION: The entry represents a CMOS parameter.
|
|
* LB_TAG_OPTION_ENUM: The entry represents a possible value for a CMOS
|
|
* parameter of type 'enum'.
|
|
*
|
|
* The CMOS table tells us where in the nonvolatile RAM to look for CMOS
|
|
* parameter values and specifies their types as 'enum', 'hex', or
|
|
* 'reserved'.
|
|
****************************************************************************/
|
|
static const struct lb_record *first_cmos_rec(uint32_t tag)
|
|
{
|
|
const char *p;
|
|
uint32_t bytes_processed, bytes_for_entries;
|
|
const struct lb_record *lbrec;
|
|
|
|
p = ((const char *)cmos_table) + cmos_table->header_length;
|
|
bytes_for_entries = cmos_table->size - cmos_table->header_length;
|
|
|
|
for (bytes_processed = 0;
|
|
bytes_processed < bytes_for_entries;
|
|
bytes_processed += lbrec->size) {
|
|
lbrec = (const struct lb_record *)&p[bytes_processed];
|
|
|
|
if (lbrec->tag == tag)
|
|
return lbrec;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* next_cmos_rec
|
|
*
|
|
* Return a pointer to the next entry after 'last' in the CMOS table whose
|
|
* type matches 'tag'. Return NULL if the table contains no more entries of
|
|
* this type.
|
|
****************************************************************************/
|
|
static const struct lb_record *next_cmos_rec(const struct lb_record *last,
|
|
uint32_t tag)
|
|
{
|
|
const char *p;
|
|
uint32_t bytes_processed, bytes_for_entries, last_offset;
|
|
const struct lb_record *lbrec;
|
|
|
|
p = ((const char *)cmos_table) + cmos_table->header_length;
|
|
bytes_for_entries = cmos_table->size - cmos_table->header_length;
|
|
last_offset = ((const char *)last) - p;
|
|
|
|
for (bytes_processed = last_offset + last->size;
|
|
bytes_processed < bytes_for_entries;
|
|
bytes_processed += lbrec->size) {
|
|
lbrec = (const struct lb_record *)&p[bytes_processed];
|
|
|
|
if (lbrec->tag == tag)
|
|
return lbrec;
|
|
}
|
|
|
|
return NULL;
|
|
}
|