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 static int options_checksum_valid(void)
36 int range_start = lib_sysinfo.cmos_range_start / 8;
37 int range_end = lib_sysinfo.cmos_range_end / 8;
38 int checksum_location = lib_sysinfo.cmos_checksum_location / 8;
39 u16 checksum = 0, checksum_old;
41 for(i = range_start; i <= range_end; i++) {
42 checksum += nvram_read(i);
44 checksum = (~checksum)&0xffff;
46 checksum_old = ((nvram_read(checksum_location)<<8) | nvram_read(checksum_location+1));
48 return (checksum_old == checksum);
51 void fix_options_checksum(void)
54 int range_start = lib_sysinfo.cmos_range_start / 8;
55 int range_end = lib_sysinfo.cmos_range_end / 8;
56 int checksum_location = lib_sysinfo.cmos_checksum_location / 8;
59 for(i = range_start; i <= range_end; i++) {
60 checksum += nvram_read(i);
62 checksum = (~checksum)&0xffff;
64 nvram_write((checksum >> 8), checksum_location);
65 nvram_write((checksum & 0xff), checksum_location + 1);
68 static int get_cmos_value(u32 bitnum, u32 len, void *valptr)
70 u8 *value = (u8 *)valptr;
75 /* Convert to byte borders */
79 /* Handle single byte or less */
81 reg8 = nvram_read(addr);
83 value[0] = reg8 & ((1 << len) -1);
87 /* When handling more than a byte, copy whole bytes */
90 value[offs++]=nvram_read(addr++);
96 int get_option(void *dest, char *name)
98 struct cb_cmos_option_table *option_table = phys_to_virt(lib_sysinfo.option_table);
99 struct cb_cmos_entries *cmos_entry;
100 int len = strnlen(name, CMOS_MAX_NAME_LENGTH);
102 /* cmos entries are located right after the option table */
104 for ( cmos_entry = (struct cb_cmos_entries*)((unsigned char *)option_table + option_table->header_length);
105 cmos_entry->tag == CB_TAG_OPTION;
106 cmos_entry = (struct cb_cmos_entries*)((unsigned char *)cmos_entry + cmos_entry->size)) {
107 if (memcmp((const char*)cmos_entry->name, name, len))
109 if(get_cmos_value(cmos_entry->bit, cmos_entry->length, dest))
112 if(!options_checksum_valid())
118 printf("ERROR: No such CMOS option (%s)\n", name);