Nico Huber | 5ce0fe1 | 2017-07-25 16:11:36 +0200 | [diff] [blame] | 1 | /* |
| 2 | * This file is part of the coreboot project. |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU General Public License as published by |
| 6 | * the Free Software Foundation; version 2 of the License. |
| 7 | * |
| 8 | * This program is distributed in the hope that it will be useful, |
| 9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 11 | * GNU General Public License for more details. |
| 12 | */ |
| 13 | |
| 14 | #include <stdint.h> |
| 15 | #ifdef __ROMCC__ |
| 16 | #include <arch/cbfs.h> |
| 17 | #else |
| 18 | #include <cbfs.h> |
| 19 | #endif |
| 20 | #include <pc80/mc146818rtc.h> |
| 21 | #if IS_ENABLED(CONFIG_USE_OPTION_TABLE) |
| 22 | #include <option_table.h> |
| 23 | #endif |
| 24 | |
| 25 | int cmos_error(void); |
| 26 | int cmos_error(void) |
| 27 | { |
| 28 | unsigned char reg_d; |
| 29 | /* See if the cmos error condition has been flagged */ |
| 30 | reg_d = cmos_read(RTC_REG_D); |
| 31 | return (reg_d & RTC_VRT) == 0; |
| 32 | } |
| 33 | |
| 34 | int cmos_chksum_valid(void); |
| 35 | int cmos_chksum_valid(void) |
| 36 | { |
| 37 | #if IS_ENABLED(CONFIG_USE_OPTION_TABLE) |
| 38 | unsigned char addr; |
| 39 | u16 sum, old_sum; |
| 40 | |
| 41 | sum = 0; |
| 42 | /* Compute the cmos checksum */ |
| 43 | for (addr = LB_CKS_RANGE_START; addr <= LB_CKS_RANGE_END; addr++) |
| 44 | sum += cmos_read(addr); |
| 45 | |
| 46 | /* Read the stored checksum */ |
| 47 | old_sum = cmos_read(LB_CKS_LOC) << 8; |
| 48 | old_sum |= cmos_read(LB_CKS_LOC + 1); |
| 49 | |
| 50 | return sum == old_sum; |
| 51 | #else |
| 52 | return 0; |
| 53 | #endif |
| 54 | } |
| 55 | |
| 56 | #if IS_ENABLED(CONFIG_USE_OPTION_TABLE) |
| 57 | void sanitize_cmos(void) |
| 58 | { |
| 59 | if (cmos_error() || !cmos_chksum_valid() || |
| 60 | IS_ENABLED(CONFIG_STATIC_OPTION_TABLE)) { |
| 61 | size_t length = 128; |
| 62 | const unsigned char *cmos_default = |
| 63 | #ifdef __ROMCC__ |
| 64 | walkcbfs("cmos.default"); |
| 65 | #else |
| 66 | cbfs_boot_map_with_leak("cmos.default", |
| 67 | CBFS_COMPONENT_CMOS_DEFAULT, &length); |
| 68 | #endif |
| 69 | if (cmos_default) { |
| 70 | int i; |
| 71 | cmos_disable_rtc(); |
| 72 | for (i = 14; i < MIN(128, length); i++) |
| 73 | cmos_write_inner(cmos_default[i], i); |
| 74 | cmos_enable_rtc(); |
| 75 | } |
| 76 | } |
| 77 | } |
| 78 | #endif |