diff options
Diffstat (limited to 'board/sc520_cdp/sc520_cdp_asm16.S')
| -rw-r--r-- | board/sc520_cdp/sc520_cdp_asm16.S | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/board/sc520_cdp/sc520_cdp_asm16.S b/board/sc520_cdp/sc520_cdp_asm16.S index a3cadcf..0e0b0c0 100644 --- a/board/sc520_cdp/sc520_cdp_asm16.S +++ b/board/sc520_cdp/sc520_cdp_asm16.S @@ -60,3 +60,25 @@ board_init16: /* the return address is tored in bp */ jmp *%bp + +.section .bios, "ax" +.code16 +.globl realmode_reset +realmode_reset: + /* Alias MMCR to 0xdf000 */ + movw $0xfffc, %dx + movl $0x800df0cb, %eax + outl %eax, %dx + + /* Set ds to point to MMCR alias */ + movw $0xdf00, %ax + movw %ax, %ds + + /* issue software reset thorugh MMCR */ + movl $0xd72, %edi + movb $0x01, %al + movb %al, (%di) + +1: hlt + jmp 1 + |