diff options
Diffstat (limited to 'src/arch/i386/lib')
| -rw-r--r-- | src/arch/i386/lib/c_start.S | 41 |
1 files changed, 21 insertions, 20 deletions
diff --git a/src/arch/i386/lib/c_start.S b/src/arch/i386/lib/c_start.S index 2e397f8847..ccd0127dae 100644 --- a/src/arch/i386/lib/c_start.S +++ b/src/arch/i386/lib/c_start.S @@ -216,7 +216,7 @@ int_hand: popl %ecx popl %edx popl %ebx - popl %ebp /* Ignore saved %esp value */ + popl %ebp /* Ignore saved %esp value */ popl %ebp popl %esi popl %edi @@ -241,49 +241,50 @@ gdb_stub_breakpoint: .globl gdt, gdt_end, gdt_limit, idtarg -gdt_limit = gdt_end - gdt - 1 /* compute the table limit */ +gdt_limit = gdt_end - gdt - 1 /* compute the table limit */ gdtaddr: .word gdt_limit - .long gdt /* we know the offset */ + .long gdt /* we know the offset */ .data + + /* This is the gdt for GCC part of LinuxBIOS. + * It is different from the gdt in ROMCC/ASM part of LinuxBIOS + * which is defined in entry32.inc */ gdt: -// selgdt 0 + /* selgdt 0, unused */ .word 0x0000, 0x0000 /* dummy */ .byte 0x00, 0x00, 0x00, 0x00 -// selgdt 8 + /* selgdt 8, unused */ .word 0x0000, 0x0000 /* dummy */ .byte 0x00, 0x00, 0x00, 0x00 -// selgdt 0x10 -/* flat code segment */ + /* selgdt 0x10, flat code segment */ .word 0xffff, 0x0000 .byte 0x00, 0x9b, 0xcf, 0x00 - -//selgdt 0x18 -/* flat data segment */ + + /* selgdt 0x18, flat data segment */ .word 0xffff, 0x0000 .byte 0x00, 0x93, 0xcf, 0x00 -//selgdt 0x20 + /* selgdt 0x20, unused */ .word 0x0000, 0x0000 /* dummy */ .byte 0x00, 0x00, 0x00, 0x00 #if defined(CONFIG_LEGACY_VGABIOS) && (CONFIG_LEGACY_VGABIOS == 1) - // from monty: - /* 0x00009a00,0000ffffULL, 20h: 16-bit 64k code at 0x00000000 */ - /* 0x00009200,0000ffffULL 28h: 16-bit 64k data at 0x00000000 */ -// selgdt 0x28 -/*16-bit 64k code at 0x00000000 */ + /* from monty: + * 0x00009a00,0000ffffULL, 20h: 16-bit 64k code at 0x00000000 + * 0x00009200,0000ffffULL 28h: 16-bit 64k data at 0x00000000 */ + + /* selgdt 0x28, 16-bit 64k code at 0x00000000 */ .word 0xffff, 0x0000 - .byte 0, 0x9a, 0, 0 + .byte 0x00, 0x9a, 0x00, 0x00 -// selgdt 0x30 -/*16-bit 64k data at 0x00000000 */ + /* selgdt 0x30, 16-bit 64k data at 0x00000000 */ .word 0xffff, 0x0000 .byte 0, 0x92, 0, 0 -#endif // defined(CONFIG_VGABIOS) && (CONFIG_VGABIOS == 1) +#endif /* defined(CONFIG_VGABIOS) && (CONFIG_VGABIOS == 1) */ gdt_end: idtarg: |