69451f17a1
Signed-off-by: Elyes Haouas <ehaouas@noos.fr> Change-Id: Ia40678019b2a54deb246dbfbf33ec37a8c3839e4 Reviewed-on: https://review.coreboot.org/c/coreboot/+/68206 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Martin Roth <martin.roth@amd.corp-partner.google.com>
63 lines
1.4 KiB
C
63 lines
1.4 KiB
C
/* SPDX-License-Identifier: GPL-2.0-only */
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#include <console/console.h>
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#include <fallback.h>
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#include <pc80/mc146818rtc.h>
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#include <stdint.h>
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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 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 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 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 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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int do_normal_boot(void)
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{
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unsigned char byte;
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if (cmos_error() || (CONFIG(USE_OPTION_TABLE) && !cmos_lb_cks_valid())) {
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printk(BIOS_WARNING,
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"Invalid CMOS checksum detected! Force fallback boot...\n");
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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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