2 * This file is part of the libpayload project.
4 * Copyright (C) 2008 coresystems GmbH
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 #include <libpayload.h>
31 #include <coreboot_tables.h>
33 u8 *mem_accessor_base;
35 static u8 mem_read(u8 reg)
37 return mem_accessor_base[reg];
40 static void mem_write(u8 val, u8 reg)
42 mem_accessor_base[reg] = val;
45 struct nvram_accessor *use_nvram = &(struct nvram_accessor) {
50 struct nvram_accessor *use_mem = &(struct nvram_accessor) {
55 struct cb_cmos_option_table *get_system_option_table(void)
57 return phys_to_virt(lib_sysinfo.option_table);
60 static int options_checksum_valid(const struct nvram_accessor *nvram)
63 int range_start = lib_sysinfo.cmos_range_start / 8;
64 int range_end = lib_sysinfo.cmos_range_end / 8;
65 int checksum_location = lib_sysinfo.cmos_checksum_location / 8;
66 u16 checksum = 0, checksum_old;
68 for(i = range_start; i <= range_end; i++) {
69 checksum += nvram->read(i);
72 checksum_old = ((nvram->read(checksum_location)<<8) | nvram->read(checksum_location+1));
74 return (checksum_old == checksum);
77 void fix_options_checksum_with(const struct nvram_accessor *nvram)
80 int range_start = lib_sysinfo.cmos_range_start / 8;
81 int range_end = lib_sysinfo.cmos_range_end / 8;
82 int checksum_location = lib_sysinfo.cmos_checksum_location / 8;
85 for(i = range_start; i <= range_end; i++) {
86 checksum += nvram->read(i);
89 nvram->write((checksum >> 8), checksum_location);
90 nvram->write((checksum & 0xff), checksum_location + 1);
93 void fix_options_checksum(void)
95 fix_options_checksum_with(use_nvram);
98 static int get_cmos_value(const struct nvram_accessor *nvram, u32 bitnum, u32 len, void *valptr)
100 u8 *value = (u8 *)valptr;
105 /* Convert to byte borders */
109 /* Handle single byte or less */
111 reg8 = nvram->read(addr);
113 value[0] = reg8 & ((1 << len) -1);
117 /* When handling more than a byte, copy whole bytes */
120 value[offs++]=nvram->read(addr++);
126 static int set_cmos_value(const struct nvram_accessor *nvram, u32 bitnum, u32 len, void *valptr)
128 u8 *value = (u8 *)valptr;
133 /* Convert to byte borders */
137 /* Handle single byte or less */
139 reg8 = nvram->read(addr);
140 reg8 &= ~(((1 << len) - 1) << bit);
141 reg8 |= (value[0] & ((1 << len) - 1)) << bit;
142 nvram->write(reg8, addr);
146 /* When handling more than a byte, copy whole bytes */
149 nvram->write(value[offs++], addr++);
155 static struct cb_cmos_entries *lookup_cmos_entry(struct cb_cmos_option_table *option_table, char *name)
157 struct cb_cmos_entries *cmos_entry;
158 int len = strnlen(name, CMOS_MAX_NAME_LENGTH);
160 /* cmos entries are located right after the option table */
162 for ( cmos_entry = (struct cb_cmos_entries*)((unsigned char *)option_table + option_table->header_length);
163 cmos_entry->tag == CB_TAG_OPTION;
164 cmos_entry = (struct cb_cmos_entries*)((unsigned char *)cmos_entry + cmos_entry->size)) {
165 if (memcmp((const char*)cmos_entry->name, name, len))
170 printf("ERROR: No such CMOS option (%s)\n", name);
174 int get_option_with(const struct nvram_accessor *nvram, struct cb_cmos_option_table *option_table, void *dest, char *name)
176 struct cb_cmos_entries *cmos_entry = lookup_cmos_entry(option_table, name);
178 if(get_cmos_value(nvram, cmos_entry->bit, cmos_entry->length, dest))
181 if(!options_checksum_valid(nvram))
189 int get_option_from(struct cb_cmos_option_table *option_table, void *dest, char *name)
191 return get_option_with(use_nvram, option_table, dest, name);
194 int get_option(void *dest, char *name)
196 return get_option_from(get_system_option_table(), dest, name);
199 int set_option_with(const struct nvram_accessor *nvram, struct cb_cmos_option_table *option_table, void *value, char *name)
201 struct cb_cmos_entries *cmos_entry = lookup_cmos_entry(option_table, name);
203 set_cmos_value(nvram, cmos_entry->bit, cmos_entry->length, value);
204 fix_options_checksum_with(nvram);
210 int set_option(void *value, char *name)
212 return set_option_with(use_nvram, get_system_option_table(), value, name);