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Hi all, I have a question
about option table; the utility
“build_opt_tbl.c” will give us an option_table.c automatically, but
where is the option_table [ ] used? How to control my Linuxbios go to fallback or normal image? We always run in fallback image. Can someone
give me some suggestions? The code is in file reset_test.inc and cmos_failover.inc.
The code total is “ #define MCH_DRC 0x7C #define DRC_IC (1 <<
29) /* If I have already
booted once skip a bunch of initialization */ /* To see if I have already booted I check to see if memory * has been enabled. */ movl $MCH_DRC, %eax PCI_READ_CONFIG_DWORD testl $DRC_IC,
%eax setnz %al testb %al,
%al jz __failover_boot __failover_reset: movb $RTC_BOOT_BYTE,
%al outb %al, $0x70 inb $0x71,
%al testb $(1<<1),
%al jnz __normal_image jmp __cpu_reset __failover_boot: /* See if the cmos clear jumper has been set */ movl $((RTC_DEVFN << 8) | GEN_PMCON_3), %eax PCI_READ_CONFIG_DWORD testl $RTC_FAILED,
%eax jz __cs_test /* There are no
impossible values, no checksums * so just trust
whatever value we have in the * cmos. */ __rtc_failed: movb $RTC_BOOT_BYTE,
%al outb %al, $0x70 inb $0x71,
%al andb $0xfc,
%al outb %al, $0x71 jmp __cs_test /* test the checksum
*/ __cs_test: movl $77,%ecx xor %ebx,%ebx movl $RTC_BOOT_BYTE, %edx 1: addl
$1, %edx movl %edx, %eax outb %al, $0x70 inb $0x71, %al addl %eax,%ebx subl $1,%ecx jnz 1b not %ebx addl
$1, %edx movl %edx, %eax outb %al, $0x70 inb $0x71, %al movb %al,%ch addl $1, %edx movl %edx, %eax outb %al, $0x70 inb $0x71, %al movb %ch,%ah cmpw %ax,%bx jz __rtc_ok /* Set to fall back
mode */ movb $RTC_BOOT_BYTE,
%al outb %al, $0x70 inb $0x71,
%al andb $0xfc,
%al outb %al, $0x71 /* The byte is o.k. see where to go */ __rtc_ok: movb $RTC_BOOT_BYTE,
%al outb %al, $0x70 inb $0x71,
%al /* Transfer the boot
bit from bit 0 to bit 1. * And clear bit 0 so that unless we say
it works we * fallback to
the other bios image immediately. */ movb %al,
%bl andb $0xfc,
%al andb $1,
%bl shlb %bl orb %bl, %al outb %al, $0x71 testb $(1<<1),
%al jnz __normal_image |
