b251753b4f
Simplify read_option(CMOS_VSTART_foo, CMOS_VLEN_foo, somedefault) to read_option(foo, somedefault) Signed-off-by: Patrick Georgi <patrick@georgi-clan.de> Acked-by: Stefan Reinauer <stefan.reinauer@coreboot.org> git-svn-id: svn://svn.coreboot.org/coreboot/trunk@6565 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1
104 lines
2.2 KiB
C
104 lines
2.2 KiB
C
#include <pc80/mc146818rtc.h>
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#include <fallback.h>
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#if CONFIG_USE_OPTION_TABLE
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#include "option_table.h"
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#endif
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#ifndef CONFIG_MAX_REBOOT_CNT
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#error "CONFIG_MAX_REBOOT_CNT not defined"
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#endif
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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 cmos_error(void)
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{
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unsigned char reg_d;
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/* See if the cmos error condition has been flagged */
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reg_d = cmos_read(RTC_REG_D);
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return (reg_d & RTC_VRT) == 0;
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}
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static int cmos_chksum_valid(void)
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{
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#if CONFIG_USE_OPTION_TABLE
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unsigned char addr;
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unsigned long sum, old_sum;
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sum = 0;
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/* Comput the cmos checksum */
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for(addr = LB_CKS_RANGE_START; addr <= LB_CKS_RANGE_END; addr++) {
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sum += cmos_read(addr);
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}
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sum = (sum & 0xffff) ^ 0xffff;
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/* Read the stored checksum */
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old_sum = cmos_read(LB_CKS_LOC) << 8;
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old_sum |= cmos_read(LB_CKS_LOC+1);
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return sum == old_sum;
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#else
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return 0;
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#endif
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}
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static inline int last_boot_normal(void)
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{
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unsigned char byte;
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byte = cmos_read(RTC_BOOT_BYTE);
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return (byte & (1 << 1));
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}
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static inline 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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/* There are no impossible values, no checksums so just
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* trust whatever value we have in the the cmos,
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* but clear the fallback bit.
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*/
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byte = cmos_read(RTC_BOOT_BYTE);
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byte &= 0x0c;
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byte |= CONFIG_MAX_REBOOT_CNT << 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 in normal mode? */
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if (byte & 1) {
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byte &= 0x0f; /* yes, clear the boot count */
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}
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/* Properly set the last boot flag */
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byte &= 0xfc;
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if ((byte >> 4) < CONFIG_MAX_REBOOT_CNT) {
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byte |= (1<<1);
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}
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/* Are we already at the max count? */
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if ((byte >> 4) < CONFIG_MAX_REBOOT_CNT) {
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byte += 1 << 4; /* No, add 1 to the count */
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}
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else {
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byte &= 0xfc; /* Yes, put in fallback mode */
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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 (byte & (1<<1));
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}
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unsigned read_option_lowlevel(unsigned start, unsigned size, unsigned def)
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{
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#if CONFIG_USE_OPTION_TABLE
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unsigned 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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