| /* |
| * This file is part of the coreboot project. |
| * |
| * 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 <stdint.h> |
| #ifdef __ROMCC__ |
| #include <arch/cbfs.h> |
| #else |
| #include <cbfs.h> |
| #endif |
| #include <pc80/mc146818rtc.h> |
| #if IS_ENABLED(CONFIG_USE_OPTION_TABLE) |
| #include <option_table.h> |
| #endif |
| |
| int cmos_error(void); |
| int cmos_error(void) |
| { |
| unsigned char reg_d; |
| /* See if the cmos error condition has been flagged */ |
| reg_d = cmos_read(RTC_REG_D); |
| return (reg_d & RTC_VRT) == 0; |
| } |
| |
| int cmos_chksum_valid(void); |
| int cmos_chksum_valid(void) |
| { |
| #if IS_ENABLED(CONFIG_USE_OPTION_TABLE) |
| unsigned char addr; |
| u16 sum, old_sum; |
| |
| sum = 0; |
| /* Compute the cmos checksum */ |
| for (addr = LB_CKS_RANGE_START; addr <= LB_CKS_RANGE_END; addr++) |
| sum += cmos_read(addr); |
| |
| /* Read the stored checksum */ |
| old_sum = cmos_read(LB_CKS_LOC) << 8; |
| old_sum |= cmos_read(LB_CKS_LOC + 1); |
| |
| return sum == old_sum; |
| #else |
| return 0; |
| #endif |
| } |
| |
| #if IS_ENABLED(CONFIG_USE_OPTION_TABLE) |
| void sanitize_cmos(void) |
| { |
| if (cmos_error() || !cmos_chksum_valid() || |
| IS_ENABLED(CONFIG_STATIC_OPTION_TABLE)) { |
| size_t length = 128; |
| const unsigned char *cmos_default = |
| #ifdef __ROMCC__ |
| walkcbfs("cmos.default"); |
| #else |
| cbfs_boot_map_with_leak("cmos.default", |
| CBFS_COMPONENT_CMOS_DEFAULT, &length); |
| #endif |
| if (cmos_default) { |
| int i; |
| cmos_disable_rtc(); |
| for (i = 14; i < MIN(128, length); i++) |
| cmos_write_inner(cmos_default[i], i); |
| cmos_enable_rtc(); |
| } |
| } |
| } |
| #endif |