| /* |
| * This file is part of the coreboot project. |
| * |
| * Copyright 2014 The Chromium OS Authors. All rights reserved. |
| * |
| * 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 <arch/acpi.h> |
| #include <bcd.h> |
| #include <stdint.h> |
| #include <version.h> |
| #include <console/console.h> |
| #include <pc80/mc146818rtc.h> |
| #include <boot/coreboot_tables.h> |
| #include <rtc.h> |
| #include <string.h> |
| #include <cbfs.h> |
| |
| /* There's no way around this include guard. option_table.h is autogenerated */ |
| #if CONFIG_USE_OPTION_TABLE |
| #include "option_table.h" |
| #else |
| #define LB_CKS_RANGE_START 0 |
| #define LB_CKS_RANGE_END 0 |
| #define LB_CKS_LOC 0 |
| #endif |
| |
| |
| static void cmos_reset_date(void) |
| { |
| /* Now setup a default date equals to the build date */ |
| struct rtc_time time = { |
| .sec = 0, |
| .min = 0, |
| .hour = 1, |
| .mday = bcd2bin(coreboot_build_date.day), |
| .mon = bcd2bin(coreboot_build_date.month), |
| .year = (bcd2bin(coreboot_build_date.century) * 100) + |
| bcd2bin(coreboot_build_date.year), |
| .wday = bcd2bin(coreboot_build_date.weekday) |
| }; |
| rtc_set(&time); |
| } |
| |
| static int cmos_checksum_valid(int range_start, int range_end, int cks_loc) |
| { |
| if (IS_ENABLED(CONFIG_STATIC_OPTION_TABLE)) |
| return 1; |
| |
| int i; |
| u16 sum, old_sum; |
| sum = 0; |
| for (i = range_start; i <= range_end; i++) |
| sum += cmos_read(i); |
| old_sum = ((cmos_read(cks_loc) << 8) | cmos_read(cks_loc + 1)) & |
| 0x0ffff; |
| return sum == old_sum; |
| } |
| |
| static void cmos_set_checksum(int range_start, int range_end, int cks_loc) |
| { |
| int i; |
| u16 sum; |
| sum = 0; |
| for (i = range_start; i <= range_end; i++) |
| sum += cmos_read(i); |
| cmos_write(((sum >> 8) & 0x0ff), cks_loc); |
| cmos_write(((sum >> 0) & 0x0ff), cks_loc + 1); |
| } |
| |
| #define RTC_CONTROL_DEFAULT (RTC_24H) |
| #define RTC_FREQ_SELECT_DEFAULT (RTC_REF_CLCK_32KHZ | RTC_RATE_1024HZ) |
| |
| #ifndef __SMM__ |
| void cmos_init(bool invalid) |
| { |
| bool cmos_invalid = invalid; |
| bool checksum_invalid = false; |
| bool clear_cmos; |
| size_t i; |
| uint8_t x; |
| |
| #ifndef __PRE_RAM__ |
| /* |
| * Avoid clearing pending interrupts and resetting the RTC control |
| * register in the resume path because the Linux kernel relies on |
| * this to know if it should restart the RTC timer queue if the wake |
| * was due to the RTC alarm. |
| */ |
| if (acpi_is_wakeup_s3()) |
| return; |
| #endif /* __PRE_RAM__ */ |
| |
| printk(BIOS_DEBUG, "RTC Init\n"); |
| |
| if (IS_ENABLED(CONFIG_USE_OPTION_TABLE)) { |
| /* See if there has been a CMOS power problem. */ |
| x = cmos_read(RTC_VALID); |
| cmos_invalid = !(x & RTC_VRT); |
| |
| /* See if there is a CMOS checksum error */ |
| checksum_invalid = !cmos_checksum_valid(PC_CKS_RANGE_START, |
| PC_CKS_RANGE_END, PC_CKS_LOC); |
| |
| clear_cmos = false; |
| } else { |
| clear_cmos = true; |
| } |
| |
| if (invalid || cmos_invalid || checksum_invalid) { |
| if (clear_cmos) { |
| cmos_write(0, 0x01); |
| cmos_write(0, 0x03); |
| cmos_write(0, 0x05); |
| for (i = 10; i < 128; i++) |
| cmos_write(0, i); |
| } |
| |
| if (cmos_invalid) |
| cmos_reset_date(); |
| |
| printk(BIOS_WARNING, "RTC:%s%s%s%s\n", |
| invalid ? " Clear requested":"", |
| cmos_invalid ? " Power Problem":"", |
| checksum_invalid ? " Checksum invalid":"", |
| clear_cmos ? " zeroing cmos":""); |
| } |
| |
| /* Setup the real time clock */ |
| cmos_write(RTC_CONTROL_DEFAULT, RTC_CONTROL); |
| /* Setup the frequency it operates at */ |
| cmos_write(RTC_FREQ_SELECT_DEFAULT, RTC_FREQ_SELECT); |
| /* Ensure all reserved bits are 0 in register D */ |
| cmos_write(RTC_VRT, RTC_VALID); |
| |
| if (IS_ENABLED(CONFIG_USE_OPTION_TABLE)) { |
| /* See if there is a LB CMOS checksum error */ |
| checksum_invalid = !cmos_checksum_valid(LB_CKS_RANGE_START, |
| LB_CKS_RANGE_END,LB_CKS_LOC); |
| if (checksum_invalid) |
| printk(BIOS_DEBUG, "RTC: coreboot checksum invalid\n"); |
| |
| /* Make certain we have a valid checksum */ |
| cmos_set_checksum(PC_CKS_RANGE_START, PC_CKS_RANGE_END, PC_CKS_LOC); |
| } |
| |
| /* Clear any pending interrupts */ |
| cmos_read(RTC_INTR_FLAGS); |
| } |
| #endif /* __SMM__ */ |
| |
| |
| /* |
| * This routine returns the value of the requested bits. |
| * input bit = bit count from the beginning of the cmos image |
| * length = number of bits to include in the value |
| * ret = a character pointer to where the value is to be returned |
| * returns CB_SUCCESS = successful, cb_err code if an error occurred |
| */ |
| static enum cb_err get_cmos_value(unsigned long bit, unsigned long length, |
| void *vret) |
| { |
| unsigned char *ret; |
| unsigned long byte,byte_bit; |
| unsigned long i; |
| unsigned char uchar; |
| |
| /* |
| * The table is checked when it is built to ensure all |
| * values are valid. |
| */ |
| ret = vret; |
| byte = bit / 8; /* find the byte where the data starts */ |
| byte_bit = bit % 8; /* find the bit in the byte where the data starts */ |
| if (length < 9) { /* one byte or less */ |
| uchar = cmos_read(byte); /* load the byte */ |
| uchar >>= byte_bit; /* shift the bits to byte align */ |
| /* clear unspecified bits */ |
| ret[0] = uchar & ((1 << length) - 1); |
| } else { /* more that one byte so transfer the whole bytes */ |
| for (i = 0; length; i++, length -= 8, byte++) { |
| /* load the byte */ |
| ret[i] = cmos_read(byte); |
| } |
| } |
| return CB_SUCCESS; |
| } |
| |
| enum cb_err get_option(void *dest, const char *name) |
| { |
| struct cmos_option_table *ct; |
| struct cmos_entries *ce; |
| size_t namelen; |
| int found = 0; |
| |
| if (!IS_ENABLED(CONFIG_USE_OPTION_TABLE)) |
| return CB_CMOS_OTABLE_DISABLED; |
| |
| /* Figure out how long name is */ |
| namelen = strnlen(name, CMOS_MAX_NAME_LENGTH); |
| |
| /* find the requested entry record */ |
| ct = cbfs_boot_map_with_leak("cmos_layout.bin", |
| CBFS_COMPONENT_CMOS_LAYOUT, NULL); |
| if (!ct) { |
| printk(BIOS_ERR, "RTC: cmos_layout.bin could not be found. " |
| "Options are disabled\n"); |
| return CB_CMOS_LAYOUT_NOT_FOUND; |
| } |
| ce = (struct cmos_entries*)((unsigned char *)ct + ct->header_length); |
| for(; ce->tag == LB_TAG_OPTION; |
| ce = (struct cmos_entries*)((unsigned char *)ce + ce->size)) { |
| if (memcmp(ce->name, name, namelen) == 0) { |
| found = 1; |
| break; |
| } |
| } |
| if (!found) { |
| printk(BIOS_DEBUG, "WARNING: No CMOS option '%s'.\n", name); |
| return CB_CMOS_OPTION_NOT_FOUND; |
| } |
| |
| if (get_cmos_value(ce->bit, ce->length, dest) != CB_SUCCESS) |
| return CB_CMOS_ACCESS_ERROR; |
| if (!cmos_checksum_valid(LB_CKS_RANGE_START, LB_CKS_RANGE_END, LB_CKS_LOC)) |
| return CB_CMOS_CHECKSUM_INVALID; |
| return CB_SUCCESS; |
| } |
| |
| static enum cb_err set_cmos_value(unsigned long bit, unsigned long length, |
| void *vret) |
| { |
| unsigned char *ret; |
| unsigned long byte,byte_bit; |
| unsigned long i; |
| unsigned char uchar, mask; |
| unsigned int chksum_update_needed = 0; |
| |
| ret = vret; |
| byte = bit / 8; /* find the byte where the data starts */ |
| byte_bit = bit % 8; /* find the bit where the data starts */ |
| if (length <= 8) { /* one byte or less */ |
| mask = (1 << length) - 1; |
| mask <<= byte_bit; |
| |
| uchar = cmos_read(byte); |
| uchar &= ~mask; |
| uchar |= (ret[0] << byte_bit); |
| cmos_write(uchar, byte); |
| if (byte >= LB_CKS_RANGE_START && byte <= LB_CKS_RANGE_END) |
| chksum_update_needed = 1; |
| } else { /* more that one byte so transfer the whole bytes */ |
| if (byte_bit || length % 8) |
| return CB_ERR_ARG; |
| |
| for (i = 0; length; i++, length -= 8, byte++) |
| cmos_write(ret[i], byte); |
| if (byte >= LB_CKS_RANGE_START && |
| byte <= LB_CKS_RANGE_END) |
| chksum_update_needed = 1; |
| } |
| |
| if (chksum_update_needed) { |
| cmos_set_checksum(LB_CKS_RANGE_START, LB_CKS_RANGE_END, |
| LB_CKS_LOC); |
| } |
| return CB_SUCCESS; |
| } |
| |
| |
| enum cb_err set_option(const char *name, void *value) |
| { |
| struct cmos_option_table *ct; |
| struct cmos_entries *ce; |
| unsigned long length; |
| size_t namelen; |
| int found = 0; |
| |
| if (!IS_ENABLED(CONFIG_USE_OPTION_TABLE)) |
| return CB_CMOS_OTABLE_DISABLED; |
| |
| /* Figure out how long name is */ |
| namelen = strnlen(name, CMOS_MAX_NAME_LENGTH); |
| |
| /* find the requested entry record */ |
| ct = cbfs_boot_map_with_leak("cmos_layout.bin", |
| CBFS_COMPONENT_CMOS_LAYOUT, NULL); |
| if (!ct) { |
| printk(BIOS_ERR, "cmos_layout.bin could not be found. " |
| "Options are disabled\n"); |
| return CB_CMOS_LAYOUT_NOT_FOUND; |
| } |
| ce = (struct cmos_entries*)((unsigned char *)ct + ct->header_length); |
| for(; ce->tag == LB_TAG_OPTION; |
| ce = (struct cmos_entries*)((unsigned char *)ce + ce->size)) { |
| if (memcmp(ce->name, name, namelen) == 0) { |
| found = 1; |
| break; |
| } |
| } |
| if (!found) { |
| printk(BIOS_DEBUG, "WARNING: No CMOS option '%s'.\n", name); |
| return CB_CMOS_OPTION_NOT_FOUND; |
| } |
| |
| length = ce->length; |
| if (ce->config == 's') { |
| length = MAX(strlen((const char *)value) * 8, ce->length - 8); |
| /* make sure the string is null terminated */ |
| if (set_cmos_value(ce->bit + ce->length - 8, 8, &(u8[]){0}) |
| != CB_SUCCESS) |
| return (CB_CMOS_ACCESS_ERROR); |
| } |
| |
| if (set_cmos_value(ce->bit, length, value) != CB_SUCCESS) |
| return (CB_CMOS_ACCESS_ERROR); |
| |
| return CB_SUCCESS; |
| } |
| |
| /* |
| * If the CMOS is cleared, the rtc_reg has the invalid date. That |
| * hurts some OSes. Even if we don't set USE_OPTION_TABLE, we need |
| * to make sure the date is valid. |
| */ |
| void cmos_check_update_date() |
| { |
| u8 year, century; |
| |
| /* Assume hardware always supports RTC_CLK_ALTCENTURY. */ |
| century = cmos_read(RTC_CLK_ALTCENTURY); |
| year = cmos_read(RTC_CLK_YEAR); |
| |
| /* |
| * TODO: If century is 0xFF, 100% that the cmos is cleared. |
| * Other than that, so far rtc_year is the only entry to check |
| * if the date is valid. |
| */ |
| if (century > 0x99 || year > 0x99) /* Invalid date */ |
| cmos_reset_date(); |
| } |
| |
| int rtc_set(const struct rtc_time *time){ |
| cmos_write(bin2bcd(time->sec), RTC_CLK_SECOND); |
| cmos_write(bin2bcd(time->min), RTC_CLK_MINUTE); |
| cmos_write(bin2bcd(time->hour), RTC_CLK_HOUR); |
| cmos_write(bin2bcd(time->mday), RTC_CLK_DAYOFMONTH); |
| cmos_write(bin2bcd(time->mon), RTC_CLK_MONTH); |
| cmos_write(bin2bcd(time->year % 100), RTC_CLK_YEAR); |
| /* Same assumption as above: We always have RTC_CLK_ALTCENTURY */ |
| cmos_write(bin2bcd(time->year / 100), RTC_CLK_ALTCENTURY); |
| cmos_write(bin2bcd(time->wday + 1), RTC_CLK_DAYOFWEEK); |
| return 0; |
| } |
| |
| int rtc_get(struct rtc_time *time) |
| { |
| time->sec = bcd2bin(cmos_read(RTC_CLK_SECOND)); |
| time->min = bcd2bin(cmos_read(RTC_CLK_MINUTE)); |
| time->hour = bcd2bin(cmos_read(RTC_CLK_HOUR)); |
| time->mday = bcd2bin(cmos_read(RTC_CLK_DAYOFMONTH)); |
| time->mon = bcd2bin(cmos_read(RTC_CLK_MONTH)); |
| time->year = bcd2bin(cmos_read(RTC_CLK_YEAR)); |
| /* Same assumption as above: We always have RTC_CLK_ALTCENTURY */ |
| time->year += bcd2bin(cmos_read(RTC_CLK_ALTCENTURY)) * 100; |
| time->wday = bcd2bin(cmos_read(RTC_CLK_DAYOFWEEK)) - 1; |
| return 0; |
| } |