ACPI video mode patch review
From: H. Peter Anvin
Date: Thu Sep 13 2007 - 17:37:32 EST
Pavel, want to look at the patch before sending it to Linus?
--- THIS IS NOT (YET) A PULL REQUEST ---
-hpa
From: H. Peter Anvin <hpa@xxxxxxxxx>
To: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Linux Kernel Mailing List <linux-kernel@xxxxxxxxxxxxxxx>
Bcc: H. Peter Anvin <hpa+sent@xxxxxxxxx>
Subject: [GIT PULL] Fix decoding of video mode numbers in acpi/wakeup.S
Hi Linus,
Please pull:
git://git.kernel.org/pub/scm/linux/kernel/git/hpa/linux-2.6-x86setup.git for-linus
H. Peter Anvin (2):
[x86 setup] Present the canonical video mode number to the kernel
[acpi] Correct the decoding of video mode numbers in wakeup.S
arch/i386/boot/video.c | 14 ++++++++---
arch/i386/kernel/acpi/wakeup.S | 41 ++++++++-------------------------
arch/x86_64/kernel/acpi/wakeup.S | 47 ++++++++++---------------------------
3 files changed, 33 insertions(+), 69 deletions(-)
[Log messages and full diffs follow]
commit 5178fb23e3e41500fd066ecd4be15a60dd373e75
Author: H. Peter Anvin <hpa@xxxxxxxxx>
Date: Thu Sep 13 14:16:37 2007 -0700
[acpi] Correct the decoding of video mode numbers in wakeup.S
wakeup.S looks at the video mode number from the setup header and
looks to see if it is a VESA mode. Unfortunately, the decoding is
done incorrectly and it will attempt to frob the VESA BIOS for any
mode number 0x0200 or larger. Correct this, and remove a bunch of #if
0'd code.
Massive thanks to Jeff Chua for reporting the bug, and suffering
though a large number of experiments in order to track this problem
down.
Cc: Pavel Machek <pavel@xxxxxx>
Signed-off-by: H. Peter Anvin <hpa@xxxxxxxxx>
diff --git a/arch/i386/kernel/acpi/wakeup.S b/arch/i386/kernel/acpi/wakeup.S
index ed0a0f2..f22ba85 100644
--- a/arch/i386/kernel/acpi/wakeup.S
+++ b/arch/i386/kernel/acpi/wakeup.S
@@ -151,51 +151,30 @@ bogus_real_magic:
#define VIDEO_FIRST_V7 0x0900
# Setting of user mode (AX=mode ID) => CF=success
+
+# For now, we only handle VESA modes (0x0200..0x03ff). To handle other
+# modes, we should probably compile in the video code from the boot
+# directory.
mode_set:
movw %ax, %bx
-#if 0
- cmpb $0xff, %ah
- jz setalias
-
- testb $VIDEO_RECALC>>8, %ah
- jnz _setrec
-
- cmpb $VIDEO_FIRST_RESOLUTION>>8, %ah
- jnc setres
-
- cmpb $VIDEO_FIRST_SPECIAL>>8, %ah
- jz setspc
-
- cmpb $VIDEO_FIRST_V7>>8, %ah
- jz setv7
-#endif
-
- cmpb $VIDEO_FIRST_VESA>>8, %ah
- jnc check_vesa
-#if 0
- orb %ah, %ah
- jz setmenu
-#endif
-
- decb %ah
-# jz setbios Add bios modes later
+ subb $VIDEO_FIRST_VESA>>8, %bh
+ cmpb $2, %bh
+ jb check_vesa
-setbad: clc
+setbad:
+ clc
ret
check_vesa:
- subb $VIDEO_FIRST_VESA>>8, %bh
orw $0x4000, %bx # Use linear frame buffer
movw $0x4f02, %ax # VESA BIOS mode set call
int $0x10
cmpw $0x004f, %ax # AL=4f if implemented
- jnz _setbad # AH=0 if OK
+ jnz setbad # AH=0 if OK
stc
ret
-_setbad: jmp setbad
-
.code32
ALIGN
diff --git a/arch/x86_64/kernel/acpi/wakeup.S b/arch/x86_64/kernel/acpi/wakeup.S
index 13f1480..a06f2bc 100644
--- a/arch/x86_64/kernel/acpi/wakeup.S
+++ b/arch/x86_64/kernel/acpi/wakeup.S
@@ -81,7 +81,7 @@ wakeup_code:
testl $2, realmode_flags - wakeup_code
jz 1f
mov video_mode - wakeup_code, %ax
- call mode_seta
+ call mode_set
1:
movw $0xb800, %ax
@@ -291,52 +291,31 @@ no_longmode:
#define VIDEO_FIRST_V7 0x0900
# Setting of user mode (AX=mode ID) => CF=success
+
+# For now, we only handle VESA modes (0x0200..0x03ff). To handle other
+# modes, we should probably compile in the video code from the boot
+# directory.
.code16
-mode_seta:
+mode_set:
movw %ax, %bx
-#if 0
- cmpb $0xff, %ah
- jz setalias
-
- testb $VIDEO_RECALC>>8, %ah
- jnz _setrec
-
- cmpb $VIDEO_FIRST_RESOLUTION>>8, %ah
- jnc setres
-
- cmpb $VIDEO_FIRST_SPECIAL>>8, %ah
- jz setspc
-
- cmpb $VIDEO_FIRST_V7>>8, %ah
- jz setv7
-#endif
-
- cmpb $VIDEO_FIRST_VESA>>8, %ah
- jnc check_vesaa
-#if 0
- orb %ah, %ah
- jz setmenu
-#endif
-
- decb %ah
-# jz setbios Add bios modes later
+ subb $VIDEO_FIRST_VESA>>8, %bh
+ cmpb $2, %bh
+ jb check_vesa
-setbada: clc
+setbad:
+ clc
ret
-check_vesaa:
- subb $VIDEO_FIRST_VESA>>8, %bh
+check_vesa:
orw $0x4000, %bx # Use linear frame buffer
movw $0x4f02, %ax # VESA BIOS mode set call
int $0x10
cmpw $0x004f, %ax # AL=4f if implemented
- jnz _setbada # AH=0 if OK
+ jnz setbad # AH=0 if OK
stc
ret
-_setbada: jmp setbada
-
wakeup_stack_begin: # Stack grows down
.org 0xff0
commit f41b4d086c58ca531ad512e1e9d6712b2310969e
Author: H. Peter Anvin <hpa@xxxxxxxxx>
Date: Thu Sep 13 14:14:29 2007 -0700
[x86 setup] Present the canonical video mode number to the kernel
Canonicalize the video mode number as presented to the kernel. The
video mode number may be user-entered (e.g. ASK_VGA), an alias
(e.g. NORMAL_VGA), or a size specification, and that confuses the
suspend wakeup code.
Signed-off-by: H. Peter Anvin <hpa@xxxxxxxxx>
diff --git a/arch/i386/boot/video.c b/arch/i386/boot/video.c
index 693f20d..e4ba897 100644
--- a/arch/i386/boot/video.c
+++ b/arch/i386/boot/video.c
@@ -147,7 +147,7 @@ int mode_defined(u16 mode)
}
/* Set mode (without recalc) */
-static int raw_set_mode(u16 mode)
+static int raw_set_mode(u16 mode, u16 *real_mode)
{
int nmode, i;
struct card_info *card;
@@ -165,8 +165,10 @@ static int raw_set_mode(u16 mode)
if ((mode == nmode && visible) ||
mode == mi->mode ||
- mode == (mi->y << 8)+mi->x)
+ mode == (mi->y << 8)+mi->x) {
+ *real_mode = mi->mode;
return card->set_mode(mi);
+ }
if (visible)
nmode++;
@@ -178,7 +180,7 @@ static int raw_set_mode(u16 mode)
if (mode >= card->xmode_first &&
mode < card->xmode_first+card->xmode_n) {
struct mode_info mix;
- mix.mode = mode;
+ *real_mode = mix.mode = mode;
mix.x = mix.y = 0;
return card->set_mode(&mix);
}
@@ -223,6 +225,7 @@ static void vga_recalc_vertical(void)
static int set_mode(u16 mode)
{
int rv;
+ u16 real_mode;
/* Very special mode numbers... */
if (mode == VIDEO_CURRENT_MODE)
@@ -232,13 +235,16 @@ static int set_mode(u16 mode)
else if (mode == EXTENDED_VGA)
mode = VIDEO_8POINT;
- rv = raw_set_mode(mode);
+ rv = raw_set_mode(mode, &real_mode);
if (rv)
return rv;
if (mode & VIDEO_RECALC)
vga_recalc_vertical();
+ /* Save the canonical mode number for the kernel, not
+ an alias, size specification or menu position */
+ boot_params.hdr.vid_mode = real_mode;
return 0;
}