Author: stepan Date: Fri Jun 4 22:32:12 2010 New Revision: 5612 URL: https://tracker.coreboot.org/trac/coreboot/changeset/5612
Log: This patch fixes the option rom code that was buggy when it switched segment registers before restoring register values. This was breaking the Geode VSA, and probably would have hurt other option roms as well. Signed-off-by: Edwin Beasant <[email protected]> Acked-by: Patrick Georgi <[email protected]> Signed-off-by: Stefan Reinauer <[email protected]> Acked-by: Nils Jacobs <[email protected]> Modified: trunk/src/devices/oprom/x86_asm.S Modified: trunk/src/devices/oprom/x86_asm.S ============================================================================== --- trunk/src/devices/oprom/x86_asm.S Fri Jun 4 22:24:11 2010 (r5611) +++ trunk/src/devices/oprom/x86_asm.S Fri Jun 4 22:32:12 2010 (r5612) @@ -141,20 +141,23 @@ mov %ax, %ds lidt __realmode_idt - /* Set all segments to 0x0000, ds to 0x0040 */ - mov %ax, %es - mov %ax, %fs - mov %ax, %gs - mov $0x40, %ax - mov %ax, %ds - /* initialize registers for option rom lcall */ movl __registers + 0, %eax movl __registers + 4, %ebx movl __registers + 8, %ecx movl __registers + 12, %edx movl __registers + 16, %esi - movl __registers + 20, %edi + movl __registers + 20, %edi + + /* Set all segments to 0x0000, ds to 0x0040 */ + push %ax + xor %ax, %ax + mov %ax, %es + mov %ax, %fs + mov %ax, %gs + mov $0x40, %ax + mov %ax, %ds + pop %ax /* ************************************ */ __lcall_instr = RELOCATED(.) @@ -262,12 +265,6 @@ mov %ax, %ds lidt __realmode_idt - /* Set all segments to 0x0000 */ - mov %ax, %ds - mov %ax, %es - mov %ax, %fs - mov %ax, %gs - /* initialize registers for intXX call */ movl __registers + 0, %eax movl __registers + 4, %ebx @@ -276,6 +273,15 @@ movl __registers + 16, %esi movl __registers + 20, %edi + /* Set all segments to 0x0000 */ + push %ax + xor %ax, %ax + mov %ax, %ds + mov %ax, %es + mov %ax, %fs + mov %ax, %gs + pop %ax + __intXX_instr = RELOCATED(.) .byte 0xcd, 0x00 /* This becomes intXX */ @@ -376,7 +382,7 @@ mov %ax, %ds lidt __realmode_idt - /* Set up segment registers to segment 0x0000 */ + /* Set up segment registers to segment 0x0000 and ds to 0x040 */ mov %ax, %es mov %ax, %fs mov %ax, %gs -- coreboot mailing list: [email protected] http://www.coreboot.org/mailman/listinfo/coreboot
