coreboot-kgpe-d16/payloads/libpayload/drivers/options.c

107 lines
3.4 KiB
C

/*
* This file is part of the libpayload project.
*
* Copyright (C) 2008 coresystems GmbH
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <libpayload.h>
#include <coreboot_tables.h>
static int options_checksum_valid(void)
{
int i;
int range_start = lib_sysinfo.cmos_range_start;
int range_end = lib_sysinfo.cmos_range_end;
int checksum_location = lib_sysinfo.cmos_checksum_location;
u16 checksum = 0, checksum_old;
for(i = range_start; i <= range_end; i++) {
checksum += nvram_read(i);
}
checksum = (~checksum)&0xffff;
checksum_old = ((nvram_read(checksum_location)<<8) | nvram_read(checksum_location+1));
return (checksum_old == checksum);
}
static int get_cmos_value(u32 bitnum, u32 len, void *valptr)
{
u8 *value = (u8 *)valptr;
int offs = 0;
u32 addr, bit;
u8 reg8;
value = valptr;
/* Convert to byte borders */
addr=(bitnum / 8);
bit=(bitnum % 8);
/* Handle single byte or less */
if(len <= 8) {
reg8 = nvram_read(addr);
reg8 >>= bit;
value[0] = reg8 & ((1 << len) -1);
return 0;
}
/* When handling more than a byte, copy whole bytes */
while (len > 0) {
len -= 8;
value[offs++]=nvram_read(addr++);
}
return 0;
}
int get_option(void *dest, char *name)
{
struct cb_cmos_option_table *option_table = lib_sysinfo.option_table;
struct cb_cmos_entries *cmos_entry;
int len = strnlen(name, CMOS_MAX_NAME_LENGTH);
/* cmos entries are located right after the option table */
cmos_entry=(struct cb_cmos_entries*)((unsigned char *)option_table + option_table->header_length);
for ( cmos_entry = (struct cb_cmos_entries*)((unsigned char *)option_table + option_table->header_length);
cmos_entry->tag == CB_TAG_OPTION;
cmos_entry = (struct cb_cmos_entries*)((unsigned char *)cmos_entry + cmos_entry->size)) {
if (memcmp(cmos_entry->name, name, len))
continue;
if(get_cmos_value(cmos_entry->bit, cmos_entry->length, dest))
return 1;
if(!options_checksum_valid())
return 1;
return 0;
}
printf("ERROR: No such CMOS option (%s)\n", name);
return 1;
}