38ddbfb325
Signed-off-by: Martin Roth <martin@coreboot.org> Change-Id: Ibb7b48a7a144421aff29acbb7ac30968ae5fe5ab Reviewed-on: https://review.coreboot.org/c/coreboot/+/36329 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Patrick Rudolph <siro@das-labor.org>
88 lines
2.2 KiB
C
88 lines
2.2 KiB
C
/*
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* This file is part of the coreboot project.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; version 2 of the License.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*/
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#include <stdint.h>
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#include <pc80/mc146818rtc.h>
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#include <fallback.h>
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#include "mc146818rtc_boot.c"
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#if CONFIG_MAX_REBOOT_CNT > 15
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#error "CONFIG_MAX_REBOOT_CNT too high"
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#endif
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static inline __attribute__((unused)) int boot_count(uint8_t rtc_byte)
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{
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return rtc_byte >> 4;
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}
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static inline __attribute__((unused)) uint8_t increment_boot_count(uint8_t rtc_byte)
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{
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return rtc_byte + (1 << 4);
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}
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static inline __attribute__((unused)) uint8_t boot_set_fallback(uint8_t rtc_byte)
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{
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return rtc_byte & ~RTC_BOOT_NORMAL;
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}
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static inline __attribute__((unused)) int boot_use_normal(uint8_t rtc_byte)
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{
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return rtc_byte & RTC_BOOT_NORMAL;
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}
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static inline __attribute__((unused)) int do_normal_boot(void)
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{
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unsigned char byte;
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if (cmos_error() || !cmos_chksum_valid()) {
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/* Invalid CMOS checksum detected!
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* Force fallback boot...
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*/
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byte = cmos_read(RTC_BOOT_BYTE);
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byte &= boot_set_fallback(byte) & 0x0f;
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byte |= 0xf << 4;
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cmos_write(byte, RTC_BOOT_BYTE);
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}
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/* The RTC_BOOT_BYTE is now o.k. see where to go. */
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byte = cmos_read(RTC_BOOT_BYTE);
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/* Are we attempting to boot normally? */
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if (boot_use_normal(byte)) {
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/* Are we already at the max count? */
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if (boot_count(byte) < CONFIG_MAX_REBOOT_CNT)
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byte = increment_boot_count(byte);
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else
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byte = boot_set_fallback(byte);
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}
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/* Save the boot byte */
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cmos_write(byte, RTC_BOOT_BYTE);
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/* Return selected code path for this boot attempt */
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return boot_use_normal(byte);
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}
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unsigned int read_option_lowlevel(unsigned int start, unsigned int size, unsigned int def)
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{
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#if CONFIG(USE_OPTION_TABLE)
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unsigned int byte;
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byte = cmos_read(start/8);
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return (byte >> (start & 7U)) & ((1U << size) - 1U);
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#else
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return def;
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#endif
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}
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