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-rw-r--r--src/drivers/pc80/rtc/Kconfig4
-rw-r--r--src/drivers/pc80/rtc/Makefile.inc15
-rw-r--r--src/drivers/pc80/rtc/mc146818rtc.c400
-rw-r--r--src/drivers/pc80/rtc/mc146818rtc_early.c104
4 files changed, 523 insertions, 0 deletions
diff --git a/src/drivers/pc80/rtc/Kconfig b/src/drivers/pc80/rtc/Kconfig
new file mode 100644
index 0000000000..350863e99a
--- /dev/null
+++ b/src/drivers/pc80/rtc/Kconfig
@@ -0,0 +1,4 @@
+config DRIVERS_MC146818
+ bool
+ default y if ARCH_X86
+ depends on PC80_SYSTEM
diff --git a/src/drivers/pc80/rtc/Makefile.inc b/src/drivers/pc80/rtc/Makefile.inc
new file mode 100644
index 0000000000..d3b3344938
--- /dev/null
+++ b/src/drivers/pc80/rtc/Makefile.inc
@@ -0,0 +1,15 @@
+ifeq ($(CONFIG_ARCH_X86),y)
+
+romstage-$(CONFIG_DRIVERS_MC146818) += mc146818rtc_early.c
+romstage-$(CONFIG_DRIVERS_MC146818) += mc146818rtc.c
+
+ramstage-$(CONFIG_DRIVERS_MC146818) += mc146818rtc_early.c
+ramstage-$(CONFIG_DRIVERS_MC146818) += mc146818rtc.c
+
+cbfs-files-$(CONFIG_HAVE_CMOS_DEFAULT) += cmos.default
+cmos.default-file = $(CONFIG_CMOS_DEFAULT_FILE):nvramtool
+cmos.default-type = 0xaa
+
+smm-$(CONFIG_DRIVERS_MC146818) += mc146818rtc.c
+
+endif
diff --git a/src/drivers/pc80/rtc/mc146818rtc.c b/src/drivers/pc80/rtc/mc146818rtc.c
new file mode 100644
index 0000000000..35dad3256a
--- /dev/null
+++ b/src/drivers/pc80/rtc/mc146818rtc.c
@@ -0,0 +1,400 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2014 The Chromium OS Authors. All rights reserved.
+ * Copyright (C) 2015 Timothy Pearson <tpearson@raptorengineeringinc.com>, Raptor Engineering
+ *
+ * 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
+
+#include <smp/spinlock.h>
+
+#if (defined(__PRE_RAM__) && \
+IS_ENABLED(CONFIG_HAVE_ROMSTAGE_NVRAM_CBFS_SPINLOCK))
+ #define LOCK_NVRAM_CBFS_SPINLOCK() spin_lock(romstage_nvram_cbfs_lock())
+ #define UNLOCK_NVRAM_CBFS_SPINLOCK() spin_unlock(romstage_nvram_cbfs_lock())
+#else
+ #define LOCK_NVRAM_CBFS_SPINLOCK() { }
+ #define UNLOCK_NVRAM_CBFS_SPINLOCK() { }
+#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)
+{
+ int i;
+ u16 sum, old_sum;
+
+ if (IS_ENABLED(CONFIG_STATIC_OPTION_TABLE))
+ return 1;
+
+ 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;
+
+ LOCK_NVRAM_CBFS_SPINLOCK();
+
+ /* 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");
+
+ UNLOCK_NVRAM_CBFS_SPINLOCK();
+ 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);
+ UNLOCK_NVRAM_CBFS_SPINLOCK();
+ return CB_CMOS_OPTION_NOT_FOUND;
+ }
+
+ if (get_cmos_value(ce->bit, ce->length, dest) != CB_SUCCESS) {
+ UNLOCK_NVRAM_CBFS_SPINLOCK();
+ return CB_CMOS_ACCESS_ERROR;
+ }
+ if (!cmos_checksum_valid(LB_CKS_RANGE_START, LB_CKS_RANGE_END, LB_CKS_LOC)) {
+ UNLOCK_NVRAM_CBFS_SPINLOCK();
+ return CB_CMOS_CHECKSUM_INVALID;
+ }
+ UNLOCK_NVRAM_CBFS_SPINLOCK();
+ 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(void)
+{
+ 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;
+}
diff --git a/src/drivers/pc80/rtc/mc146818rtc_early.c b/src/drivers/pc80/rtc/mc146818rtc_early.c
new file mode 100644
index 0000000000..8bebc4229d
--- /dev/null
+++ b/src/drivers/pc80/rtc/mc146818rtc_early.c
@@ -0,0 +1,104 @@
+#include <stdint.h>
+#include <pc80/mc146818rtc.h>
+#include <fallback.h>
+#if CONFIG_USE_OPTION_TABLE
+#include "option_table.h"
+#endif
+
+#if CONFIG_MAX_REBOOT_CNT > 15
+#error "CONFIG_MAX_REBOOT_CNT too high"
+#endif
+
+static 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;
+}
+
+static int cmos_chksum_valid(void)
+{
+#if 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
+}
+
+static inline __attribute__((unused)) int boot_count(uint8_t rtc_byte)
+{
+ return rtc_byte >> 4;
+}
+
+static inline __attribute__((unused)) uint8_t increment_boot_count(uint8_t rtc_byte)
+{
+ return rtc_byte + (1 << 4);
+}
+
+static inline __attribute__((unused)) uint8_t boot_set_fallback(uint8_t rtc_byte)
+{
+ return rtc_byte & ~RTC_BOOT_NORMAL;
+}
+
+static inline __attribute__((unused)) int boot_use_normal(uint8_t rtc_byte)
+{
+ return rtc_byte & RTC_BOOT_NORMAL;
+}
+
+static inline __attribute__((unused)) int do_normal_boot(void)
+{
+ unsigned char byte;
+
+ if (cmos_error() || !cmos_chksum_valid()) {
+ /* Invalid CMOS checksum detected!
+ * Force fallback boot...
+ */
+ byte = cmos_read(RTC_BOOT_BYTE);
+ byte &= boot_set_fallback(byte) & 0x0f;
+ byte |= 0xf << 4;
+ cmos_write(byte, RTC_BOOT_BYTE);
+ }
+
+ /* The RTC_BOOT_BYTE is now o.k. see where to go. */
+ byte = cmos_read(RTC_BOOT_BYTE);
+
+ /* Are we attempting to boot normally? */
+ if (boot_use_normal(byte)) {
+ /* Are we already at the max count? */
+ if (boot_count(byte) < CONFIG_MAX_REBOOT_CNT)
+ byte = increment_boot_count(byte);
+ else
+ byte = boot_set_fallback(byte);
+ }
+
+ /* Save the boot byte */
+ cmos_write(byte, RTC_BOOT_BYTE);
+
+ /* Return selected code path for this boot attempt */
+ return boot_use_normal(byte);
+}
+
+unsigned read_option_lowlevel(unsigned start, unsigned size, unsigned def)
+{
+#if CONFIG_USE_OPTION_TABLE
+ unsigned byte;
+
+ byte = cmos_read(start/8);
+ return (byte >> (start & 7U)) & ((1U << size) - 1U);
+#else
+ return def;
+#endif
+}