On 6/4/10 6:40 PM, Stefan Reinauer wrote:
> On 6/4/10 6:37 PM, Patrick Georgi wrote:
>
>> Am Freitag, den 04.06.2010, 16:25 +0100 schrieb Edwin Beasant:
>>
>>
>>> 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]
>>>
>>>
>> Except for the first two parts (the magic values in ecx/edx and
>> whitespace), and assuming this is tested, the patch is
>>
>> Acked-by: Patrick Georgi <[email protected]>
>>
>>
>>
>>
> I did a new version of the patch with those issues fixed (and pushing
> one register instead of all), see attachment
>
> Signed-off-by: Edwin Beasant <[email protected]>
> Signed-off-by: Stefan Reinauer <[email protected]>
>
Updated patch.
Index: src/devices/oprom/x86_asm.S
===================================================================
--- src/devices/oprom/x86_asm.S (revision 5608)
+++ src/devices/oprom/x86_asm.S (working copy)
@@ -141,21 +141,24 @@
mov %ax, %ds
lidt __realmode_idt
+ /* 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
+
/* 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
- /* 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
-
/* ************************************ */
__lcall_instr = RELOCATED(.)
.byte 0x9a
@@ -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
--
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