[PATCH] Don't probe for DDC on VBE1.2

[PATCH] Don't probe for DDC on VBE1.2

[Zwane Mwaikambo]

VBE1.2 doesn't support function 15h (DDC) resulting in a 'hang' whilst
uncompressing kernel with some video cards. Make sure we check VBE version 
before fiddling around with DDC.

http://bugzilla.kernel.org/show_bug.cgi?id=1458

Opened: 2003-10-30 09:12 Last update: 2007-02-13 22:03

:(

Much thanks to Tobias Hain for help in testing and investigating the bug. 
Tested on;

i386, Chips & Technologies 65548 VESA VBE 1.2
CONFIG_VIDEO_SELECT=Y
CONFIG_FIRMWARE_EDID=Y

Untested on x86_64.

Signed-off-by: Zwane Mwaikambo <zwane@infradead.org>

Index: linux-2.6.20-rc6-mm1/arch/i386/boot/video.S
===================================================================
RCS file: /home/cvsroot/linux-2.6.20-rc6-mm1/arch/i386/boot/video.S,v
retrieving revision 1.1.1.1
diff -u -p -B -r1.1.1.1 video.S
--- linux-2.6.20-rc6-mm1/arch/i386/boot/video.S	30 Jan 2007 05:28:31 -0000	1.1.1.1
+++ linux-2.6.20-rc6-mm1/arch/i386/boot/video.S	15 Feb 2007 16:27:32 -0000
@@ -1945,6 +1945,20 @@ store_edid:
 	rep
 	stosl
 
+	pushw	%es
+	pushw	%ds
+	popw	%es
+	leaw	modelist+1024, %di
+	movw	$0x4f00, %ax
+	int	$0x10
+	popw	%es
+
+	cmpw	$0x004f, %ax
+	jne	no_edid
+
+	cmpw	$0x0102, 4(%di)			# only do EDID on > 1.2
+	je	no_edid
+
 	pushw   %es				# save ES
 	xorw    %di, %di                        # Report Capability
 	pushw   %di
Index: linux-2.6.20-rc6-mm1/arch/x86_64/boot/video.S
===================================================================
RCS file: /home/cvsroot/linux-2.6.20-rc6-mm1/arch/x86_64/boot/video.S,v
retrieving revision 1.1.1.1
diff -u -p -B -r1.1.1.1 video.S
--- linux-2.6.20-rc6-mm1/arch/x86_64/boot/video.S	30 Jan 2007 05:28:36 -0000	1.1.1.1
+++ linux-2.6.20-rc6-mm1/arch/x86_64/boot/video.S	15 Feb 2007 16:27:32 -0000
@@ -1945,6 +1945,20 @@ store_edid:
 	rep
 	stosl
 
+	pushw	%es
+	pushw	%ds
+	popw	%es
+	leaw	modelist+1024, %di
+	movw	$0x4f00, %ax
+	int	$0x10
+	popw	%es
+
+	cmpw	$0x004f, %ax
+	jne	no_edid
+
+	cmpw	$0x0102, 4(%di)			# only do EDID on > 1.2
+	je	no_edid
+
 	pushw   %es				# save ES
 	xorw    %di, %di                        # Report Capability
 	pushw   %di

Re: [PATCH] Don't probe for DDC on VBE1.2

[Randy Dunlap]

On Thu, 15 Feb 2007 08:29:49 -0800 (PST) Zwane Mwaikambo wrote:

> VBE1.2 doesn't support function 15h (DDC) resulting in a 'hang' whilst
> uncompressing kernel with some video cards. Make sure we check VBE version 
> before fiddling around with DDC.
> 
> http://bugzilla.kernel.org/show_bug.cgi?id=1458
> 
> Opened: 2003-10-30 09:12 Last update: 2007-02-13 22:03
> 
> :(

true.

Just one question:  why use 'je' instead of 'jle' (jge ?) : check for
current version <= 0x0102, whatever that is in gas; I'm still used
to intel syntax.

> Much thanks to Tobias Hain for help in testing and investigating the bug. 
> Tested on;
> 
> i386, Chips & Technologies 65548 VESA VBE 1.2
> CONFIG_VIDEO_SELECT=Y
> CONFIG_FIRMWARE_EDID=Y
> 
> Untested on x86_64.
> 
> Signed-off-by: Zwane Mwaikambo <zwane@infradead.org>
> 
> Index: linux-2.6.20-rc6-mm1/arch/i386/boot/video.S
> ===================================================================
> RCS file: /home/cvsroot/linux-2.6.20-rc6-mm1/arch/i386/boot/video.S,v
> retrieving revision 1.1.1.1
> diff -u -p -B -r1.1.1.1 video.S
> --- linux-2.6.20-rc6-mm1/arch/i386/boot/video.S	30 Jan 2007 05:28:31 -0000	1.1.1.1
> +++ linux-2.6.20-rc6-mm1/arch/i386/boot/video.S	15 Feb 2007 16:27:32 -0000
> @@ -1945,6 +1945,20 @@ store_edid:
>  	rep
>  	stosl
>  
> +	pushw	%es
> +	pushw	%ds
> +	popw	%es
> +	leaw	modelist+1024, %di
> +	movw	$0x4f00, %ax
> +	int	$0x10
> +	popw	%es
> +
> +	cmpw	$0x004f, %ax
> +	jne	no_edid
> +
> +	cmpw	$0x0102, 4(%di)			# only do EDID on > 1.2
> +	je	no_edid
> +
>  	pushw   %es				# save ES
>  	xorw    %di, %di                        # Report Capability
>  	pushw   %di
> Index: linux-2.6.20-rc6-mm1/arch/x86_64/boot/video.S
> ===================================================================
> RCS file: /home/cvsroot/linux-2.6.20-rc6-mm1/arch/x86_64/boot/video.S,v
> retrieving revision 1.1.1.1
> diff -u -p -B -r1.1.1.1 video.S
> --- linux-2.6.20-rc6-mm1/arch/x86_64/boot/video.S	30 Jan 2007 05:28:36 -0000	1.1.1.1
> +++ linux-2.6.20-rc6-mm1/arch/x86_64/boot/video.S	15 Feb 2007 16:27:32 -0000
> @@ -1945,6 +1945,20 @@ store_edid:
>  	rep
>  	stosl
>  
> +	pushw	%es
> +	pushw	%ds
> +	popw	%es
> +	leaw	modelist+1024, %di
> +	movw	$0x4f00, %ax
> +	int	$0x10
> +	popw	%es
> +
> +	cmpw	$0x004f, %ax
> +	jne	no_edid
> +
> +	cmpw	$0x0102, 4(%di)			# only do EDID on > 1.2
> +	je	no_edid
> +
>  	pushw   %es				# save ES
>  	xorw    %di, %di                        # Report Capability
>  	pushw   %di
> -

---
~Randy
*** Remember to use Documentation/SubmitChecklist when testing your code ***

Re: [PATCH] Don't probe for DDC on VBE1.2

[Zwane Mwaikambo]

On Thu, 15 Feb 2007, Randy Dunlap wrote:

> On Thu, 15 Feb 2007 08:29:49 -0800 (PST) Zwane Mwaikambo wrote:
> 
> > VBE1.2 doesn't support function 15h (DDC) resulting in a 'hang' whilst
> > uncompressing kernel with some video cards. Make sure we check VBE version 
> > before fiddling around with DDC.
> > 
> > http://bugzilla.kernel.org/show_bug.cgi?id=1458
> > 
> > Opened: 2003-10-30 09:12 Last update: 2007-02-13 22:03
> > 
> > :(
> 
> true.
> 
> Just one question:  why use 'je' instead of 'jle' (jge ?) : check for
> current version <= 0x0102, whatever that is in gas; I'm still used
> to intel syntax.

Good point;

Signed-off-by: Zwane Mwaikambo <zwane@infradead.org>

Index: linux-2.6.20-mm1/arch/i386/boot/video.S
===================================================================
RCS file: /home/cvsroot/linux-2.6.20-mm1/arch/i386/boot/video.S,v
retrieving revision 1.1.1.1
diff -u -p -B -r1.1.1.1 video.S
--- linux-2.6.20-mm1/arch/i386/boot/video.S	15 Feb 2007 17:35:57 -0000	1.1.1.1
+++ linux-2.6.20-mm1/arch/i386/boot/video.S	15 Feb 2007 22:28:34 -0000
@@ -1945,6 +1945,20 @@ store_edid:
 	rep
 	stosl
 
+	pushw	%es
+	pushw	%ds
+	popw	%es
+	leaw	modelist+1024, %di
+	movw	$0x4f00, %ax
+	int	$0x10
+	popw	%es
+
+	cmpw	$0x004f, %ax
+	jne	no_edid
+
+	cmpw	$0x0102, 4(%di)			# only do EDID on > 1.2
+	jle	no_edid
+
 	pushw   %es				# save ES
 	xorw    %di, %di                        # Report Capability
 	pushw   %di
Index: linux-2.6.20-mm1/arch/x86_64/boot/video.S
===================================================================
RCS file: /home/cvsroot/linux-2.6.20-mm1/arch/x86_64/boot/video.S,v
retrieving revision 1.1.1.1
diff -u -p -B -r1.1.1.1 video.S
--- linux-2.6.20-mm1/arch/x86_64/boot/video.S	15 Feb 2007 17:36:18 -0000	1.1.1.1
+++ linux-2.6.20-mm1/arch/x86_64/boot/video.S	15 Feb 2007 22:29:00 -0000
@@ -1945,6 +1945,20 @@ store_edid:
 	rep
 	stosl
 
+	pushw	%es
+	pushw	%ds
+	popw	%es
+	leaw	modelist+1024, %di
+	movw	$0x4f00, %ax
+	int	$0x10
+	popw	%es
+
+	cmpw	$0x004f, %ax
+	jne	no_edid
+
+	cmpw	$0x0102, 4(%di)			# only do EDID on > 1.2
+	jle	no_edid
+
 	pushw   %es				# save ES
 	xorw    %di, %di                        # Report Capability
 	pushw   %di

Re: [PATCH] Don't probe for DDC on VBE1.2

[Andrew Morton]

On Thu, 15 Feb 2007 08:29:49 -0800 (PST) Zwane Mwaikambo <zwane@infradead.org> wrote:

> VBE1.2 doesn't support function 15h (DDC) resulting in a 'hang' whilst
> uncompressing kernel with some video cards. Make sure we check VBE version 
> before fiddling around with DDC.
> 
> http://bugzilla.kernel.org/show_bug.cgi?id=1458
> 
> Opened: 2003-10-30 09:12 Last update: 2007-02-13 22:03
> 
> :(
> 
> Much thanks to Tobias Hain for help in testing and investigating the bug. 
> Tested on;
> 
> i386, Chips & Technologies 65548 VESA VBE 1.2
> CONFIG_VIDEO_SELECT=Y
> CONFIG_FIRMWARE_EDID=Y
> 
> Untested on x86_64.
> 
> Signed-off-by: Zwane Mwaikambo <zwane@infradead.org>
> 
> Index: linux-2.6.20-rc6-mm1/arch/i386/boot/video.S
> ===================================================================
> RCS file: /home/cvsroot/linux-2.6.20-rc6-mm1/arch/i386/boot/video.S,v
> retrieving revision 1.1.1.1
> diff -u -p -B -r1.1.1.1 video.S
> --- linux-2.6.20-rc6-mm1/arch/i386/boot/video.S	30 Jan 2007 05:28:31 -0000	1.1.1.1
> +++ linux-2.6.20-rc6-mm1/arch/i386/boot/video.S	15 Feb 2007 16:27:32 -0000
> @@ -1945,6 +1945,20 @@ store_edid:
>  	rep
>  	stosl
>  
> +	pushw	%es
> +	pushw	%ds
> +	popw	%es
> +	leaw	modelist+1024, %di
> +	movw	$0x4f00, %ax
> +	int	$0x10
> +	popw	%es
> +
> +	cmpw	$0x004f, %ax
> +	jne	no_edid
> +
> +	cmpw	$0x0102, 4(%di)			# only do EDID on > 1.2
> +	je	no_edid
> +
>  	pushw   %es				# save ES
>  	xorw    %di, %di                        # Report Capability
>  	pushw   %di

This makes the long-suffering-but-vigorously-defended Vaio come up with a
black display.  Everything's working OK otherwise.  Sort of a Black Screen
of Life.  I wouldn't call it an improvement though.

Re: [PATCH] Don't probe for DDC on VBE1.2

[Zwane Mwaikambo]

On Thu, 15 Feb 2007, Andrew Morton wrote:

> This makes the long-suffering-but-vigorously-defended Vaio come up with a
> black display.  Everything's working OK otherwise.  Sort of a Black Screen
> of Life.  I wouldn't call it an improvement though.

Bugger, what does your kernel commandline look like?

Re: [PATCH] Don't probe for DDC on VBE1.2

[Andrew Morton]

On Thu, 15 Feb 2007 21:35:35 -0800 (PST) Zwane Mwaikambo <zwane@infradead.org> wrote:

> On Thu, 15 Feb 2007, Andrew Morton wrote:
> 
> > This makes the long-suffering-but-vigorously-defended Vaio come up with a
> > black display.  Everything's working OK otherwise.  Sort of a Black Screen
> > of Life.  I wouldn't call it an improvement though.
> 
> Bugger, what does your kernel commandline look like?

Kernel command line: ro root=LABEL=/ rhgb vga=0x263 clock=pit

http://userweb.kernel.org/~akpm/dmesg-sony.txt

Re: [PATCH] Don't probe for DDC on VBE1.2

[Andrew Morton]

On Thu, 15 Feb 2007 21:45:06 -0800 Andrew Morton <akpm@linux-foundation.org> wrote:

> On Thu, 15 Feb 2007 21:35:35 -0800 (PST) Zwane Mwaikambo <zwane@infradead.org> wrote:
> 
> > On Thu, 15 Feb 2007, Andrew Morton wrote:
> > 
> > > This makes the long-suffering-but-vigorously-defended Vaio come up with a
> > > black display.  Everything's working OK otherwise.  Sort of a Black Screen
> > > of Life.  I wouldn't call it an improvement though.
> > 
> > Bugger, what does your kernel commandline look like?
> 
> Kernel command line: ro root=LABEL=/ rhgb vga=0x263 clock=pit

Removing the vga=0x263 "fixes" it.

Re: [PATCH] Don't probe for DDC on VBE1.2

[Zwane Mwaikambo]

On Thu, 15 Feb 2007, Andrew Morton wrote:

> On Thu, 15 Feb 2007 21:45:06 -0800 Andrew Morton <akpm@linux-foundation.org> wrote:
> 
> > On Thu, 15 Feb 2007 21:35:35 -0800 (PST) Zwane Mwaikambo <zwane@infradead.org> wrote:
> > 
> > > On Thu, 15 Feb 2007, Andrew Morton wrote:
> > > 
> > > > This makes the long-suffering-but-vigorously-defended Vaio come up with a
> > > > black display.  Everything's working OK otherwise.  Sort of a Black Screen
> > > > of Life.  I wouldn't call it an improvement though.
> > > 
> > > Bugger, what does your kernel commandline look like?
> > 
> > Kernel command line: ro root=LABEL=/ rhgb vga=0x263 clock=pit
> 
> Removing the vga=0x263 "fixes" it.
> 

Sorry i missed this earlier, could you also post up an Xorg.0.log (or 
equivalent for your system).

Thanks,
	Zwane

Re: [PATCH] Don't probe for DDC on VBE1.2

[Andrew Morton]

On Thu, 15 Feb 2007 21:59:06 -0800 (PST) Zwane Mwaikambo <zwane@infradead.org> wrote:

> On Thu, 15 Feb 2007, Andrew Morton wrote:
> 
> > On Thu, 15 Feb 2007 21:45:06 -0800 Andrew Morton <akpm@linux-foundation.org> wrote:
> > 
> > > On Thu, 15 Feb 2007 21:35:35 -0800 (PST) Zwane Mwaikambo <zwane@infradead.org> wrote:
> > > 
> > > > On Thu, 15 Feb 2007, Andrew Morton wrote:
> > > > 
> > > > > This makes the long-suffering-but-vigorously-defended Vaio come up with a
> > > > > black display.  Everything's working OK otherwise.  Sort of a Black Screen
> > > > > of Life.  I wouldn't call it an improvement though.
> > > > 
> > > > Bugger, what does your kernel commandline look like?
> > > 
> > > Kernel command line: ro root=LABEL=/ rhgb vga=0x263 clock=pit
> > 
> > Removing the vga=0x263 "fixes" it.
> > 
> 
> Sorry i missed this earlier, could you also post up an Xorg.0.log (or 
> equivalent for your system).
> 

It's not an X problem - the screen is black immediately upon loading the
kernel.

But I guess you knew that and you're just after display info:
http://userweb.kernel.org/~akpm/Xorg.0.log.txt

Re: [PATCH] Don't probe for DDC on VBE1.2

[Zwane Mwaikambo]

On Thu, 15 Feb 2007, Andrew Morton wrote:

> It's not an X problem - the screen is black immediately upon loading the
> kernel.
> 
> But I guess you knew that and you're just after display info:
> http://userweb.kernel.org/~akpm/Xorg.0.log.txt

Thanks, the X log told me your VBE version. I tried to reproduce it on my 
thinkpad which seems to have a very similar video setup to no avail, Could 
you test the following on the VAIO? If this isn't the case, i suspect i'm 
corrupting your modelist.

P.s. Thanks for the vga=0x263!

Index: linux-2.6.20-mm1/arch/i386/boot/video.S
===================================================================
RCS file: /home/cvsroot/linux-2.6.20-mm1/arch/i386/boot/video.S,v
retrieving revision 1.1.1.1
diff -u -p -B -r1.1.1.1 video.S
--- linux-2.6.20-mm1/arch/i386/boot/video.S	15 Feb 2007 17:35:57 -0000	1.1.1.1
+++ linux-2.6.20-mm1/arch/i386/boot/video.S	16 Feb 2007 12:58:20 -0000
@@ -1945,6 +1945,25 @@ store_edid:
 	rep
 	stosl
 
+	pushw	%es
+	pushw	%ds
+	popw	%es
+	leaw	modelist+1024, %di
+	movw    $0x02b3, %ax
+	movw    %ax, (%di)
+	movw    $0x9d4a, %ax
+	movw    %ax, 2(%di)                     # set signature to "vbe2"
+
+	movw	$0x4f00, %ax
+	int	$0x10
+	popw	%es
+
+	cmpw	$0x004f, %ax
+	jne	no_edid
+
+	cmpw	$0x0200, 4(%di)			# only do EDID on >= VBE2.0
+	jl	no_edid
+
 	pushw   %es				# save ES
 	xorw    %di, %di                        # Report Capability
 	pushw   %di
Index: linux-2.6.20-mm1/arch/x86_64/boot/video.S
===================================================================
RCS file: /home/cvsroot/linux-2.6.20-mm1/arch/x86_64/boot/video.S,v
retrieving revision 1.1.1.1
diff -u -p -B -r1.1.1.1 video.S
--- linux-2.6.20-mm1/arch/x86_64/boot/video.S	15 Feb 2007 17:36:18 -0000	1.1.1.1
+++ linux-2.6.20-mm1/arch/x86_64/boot/video.S	16 Feb 2007 12:57:57 -0000
@@ -1945,6 +1945,25 @@ store_edid:
 	rep
 	stosl
 
+	pushw	%es
+	pushw	%ds
+	popw	%es
+	leaw	modelist+1024, %di
+	movw    $0x02b3, %ax
+	movw    %ax, (%di)
+	movw    $0x9d4a, %ax
+	movw    %ax, 2(%di)                     # set signature to "vbe2"
+
+	movw	$0x4f00, %ax
+	int	$0x10
+	popw	%es
+
+	cmpw	$0x004f, %ax
+	jne	no_edid
+
+	cmpw	$0x0200, 4(%di)			# only do EDID on >= VBE2.0
+	jl	no_edid
+
 	pushw   %es				# save ES
 	xorw    %di, %di                        # Report Capability
 	pushw   %di

Re: [PATCH] Don't probe for DDC on VBE1.2

[Andrew Morton]

On Fri, 16 Feb 2007 06:39:45 -0800 (PST) Zwane Mwaikambo <zwane@infradead.org> wrote:

> On Thu, 15 Feb 2007, Andrew Morton wrote:
> 
> > It's not an X problem - the screen is black immediately upon loading the
> > kernel.
> > 
> > But I guess you knew that and you're just after display info:
> > http://userweb.kernel.org/~akpm/Xorg.0.log.txt
> 
> Thanks, the X log told me your VBE version. I tried to reproduce it on my 
> thinkpad which seems to have a very similar video setup to no avail, Could 
> you test the following on the VAIO? If this isn't the case, i suspect i'm 
> corrupting your modelist.

It's still all black.

Re: [PATCH] Don't probe for DDC on VBE1.2

[Zwane Mwaikambo]

On Fri, 16 Feb 2007, Andrew Morton wrote:

> On Fri, 16 Feb 2007 06:39:45 -0800 (PST) Zwane Mwaikambo <zwane@infradead.org> wrote:
> 
> > On Thu, 15 Feb 2007, Andrew Morton wrote:
> > 
> > > It's not an X problem - the screen is black immediately upon loading the
> > > kernel.
> > > 
> > > But I guess you knew that and you're just after display info:
> > > http://userweb.kernel.org/~akpm/Xorg.0.log.txt
> > 
> > Thanks, the X log told me your VBE version. I tried to reproduce it on my 
> > thinkpad which seems to have a very similar video setup to no avail, Could 
> > you test the following on the VAIO? If this isn't the case, i suspect i'm 
> > corrupting your modelist.
> 
> It's still all black.

Ok it looks like i was corrupting the modelist. The following should take 
care of your VAIO, but i haven't tested the failure case as Tobias is away 
this weekend.

Index: linux-2.6.20-mm1/arch/i386/boot/video.S
===================================================================
RCS file: /home/cvsroot/linux-2.6.20-mm1/arch/i386/boot/video.S,v
retrieving revision 1.1.1.1
diff -u -p -B -r1.1.1.1 video.S
--- linux-2.6.20-mm1/arch/i386/boot/video.S	15 Feb 2007 17:35:57 -0000	1.1.1.1
+++ linux-2.6.20-mm1/arch/i386/boot/video.S	17 Feb 2007 08:29:11 -0000
@@ -571,6 +571,16 @@ setr1:	lodsw
 	jmp	_m_s
 
 check_vesa:
+#ifdef CONFIG_FIRMWARE_EDID
+	leaw	modelist+1024, %di
+	movw	$0x4f00, %ax
+	int	$0x10
+	cmpw	$0x004f, %ax
+	jnz	setbad
+	
+	movw	4(%di), %ax
+	movw	%ax, vbe_version
+#endif
 	leaw	modelist+1024, %di
 	subb	$VIDEO_FIRST_VESA>>8, %bh
 	movw	%bx, %cx			# Get mode information structure
@@ -1945,6 +1955,9 @@ store_edid:
 	rep
 	stosl
 
+	cmpw	$0x0200, vbe_version		# only do EDID on >= VBE2.0
+	jl	no_edid
+
 	pushw   %es				# save ES
 	xorw    %di, %di                        # Report Capability
 	pushw   %di
@@ -1987,6 +2000,7 @@ do_restore:	.byte	0	# Screen contents al
 svga_prefix:	.byte	VIDEO_FIRST_BIOS>>8	# Default prefix for BIOS modes
 graphic_mode:	.byte	0	# Graphic mode with a linear frame buffer
 dac_size:	.byte	6	# DAC bit depth
+vbe_version:	.word	0	# VBE bios version
 
 # Status messages
 keymsg:		.ascii	"Press <RETURN> to see video modes available, "
Index: linux-2.6.20-mm1/arch/x86_64/boot/video.S
===================================================================
RCS file: /home/cvsroot/linux-2.6.20-mm1/arch/x86_64/boot/video.S,v
retrieving revision 1.1.1.1
diff -u -p -B -r1.1.1.1 video.S
--- linux-2.6.20-mm1/arch/x86_64/boot/video.S	15 Feb 2007 17:36:18 -0000	1.1.1.1
+++ linux-2.6.20-mm1/arch/x86_64/boot/video.S	17 Feb 2007 08:29:11 -0000
@@ -571,6 +571,16 @@ setr1:	lodsw
 	jmp	_m_s
 
 check_vesa:
+#ifdef CONFIG_FIRMWARE_EDID
+	leaw	modelist+1024, %di
+	movw	$0x4f00, %ax
+	int	$0x10
+	cmpw	$0x004f, %ax
+	jnz	setbad
+	
+	movw	4(%di), %ax
+	movw	%ax, vbe_version
+#endif
 	leaw	modelist+1024, %di
 	subb	$VIDEO_FIRST_VESA>>8, %bh
 	movw	%bx, %cx			# Get mode information structure
@@ -1945,6 +1955,9 @@ store_edid:
 	rep
 	stosl
 
+	cmpw	$0x0200, vbe_version		# only do EDID on >= VBE2.0
+	jl	no_edid
+
 	pushw   %es				# save ES
 	xorw    %di, %di                        # Report Capability
 	pushw   %di
@@ -1987,6 +2000,7 @@ do_restore:	.byte	0	# Screen contents al
 svga_prefix:	.byte	VIDEO_FIRST_BIOS>>8	# Default prefix for BIOS modes
 graphic_mode:	.byte	0	# Graphic mode with a linear frame buffer
 dac_size:	.byte	6	# DAC bit depth
+vbe_version:	.word	0	# VBE bios version
 
 # Status messages
 keymsg:		.ascii	"Press <RETURN> to see video modes available, "

Re: [PATCH] Don't probe for DDC on VBE1.2

[Andrew Morton]

On Sat, 17 Feb 2007 00:35:52 -0800 (PST) Zwane Mwaikambo <zwane@infradead.org> wrote:

> On Fri, 16 Feb 2007, Andrew Morton wrote:
> 
> > On Fri, 16 Feb 2007 06:39:45 -0800 (PST) Zwane Mwaikambo <zwane@infradead.org> wrote:
> > 
> > > On Thu, 15 Feb 2007, Andrew Morton wrote:
> > > 
> > > > It's not an X problem - the screen is black immediately upon loading the
> > > > kernel.
> > > > 
> > > > But I guess you knew that and you're just after display info:
> > > > http://userweb.kernel.org/~akpm/Xorg.0.log.txt
> > > 
> > > Thanks, the X log told me your VBE version. I tried to reproduce it on my 
> > > thinkpad which seems to have a very similar video setup to no avail, Could 
> > > you test the following on the VAIO? If this isn't the case, i suspect i'm 
> > > corrupting your modelist.
> > 
> > It's still all black.
> 
> Ok it looks like i was corrupting the modelist. The following should take 
> care of your VAIO, but i haven't tested the failure case as Tobias is away 
> this weekend.

yup, no longer all black.

AW: [PATCH] Don't probe for DDC on VBE1.2

[Tobias Hain]

> Ok it looks like i was corrupting the modelist. The following should take 
> care of your VAIO, but i haven't tested the failure case as Tobias is away

> this weekend.

Yes, this last patch also works on VBE 1.2: It skips the EDID calls, which
would crash my system here, and consequently boots the kernel fine.

Thanks,
tobias

Re: [PATCH] Don't probe for DDC on VBE1.2

[Andi Kleen]

On Saturday 17 February 2007 09:35, Zwane Mwaikambo wrote:
> On Fri, 16 Feb 2007, Andrew Morton wrote:
> 
> > On Fri, 16 Feb 2007 06:39:45 -0800 (PST) Zwane Mwaikambo <zwane@infradead.org> wrote:
> > 
> > > On Thu, 15 Feb 2007, Andrew Morton wrote:
> > > 
> > > > It's not an X problem - the screen is black immediately upon loading the
> > > > kernel.
> > > > 
> > > > But I guess you knew that and you're just after display info:
> > > > http://userweb.kernel.org/~akpm/Xorg.0.log.txt
> > > 
> > > Thanks, the X log told me your VBE version. I tried to reproduce it on my 
> > > thinkpad which seems to have a very similar video setup to no avail, Could 
> > > you test the following on the VAIO? If this isn't the case, i suspect i'm 
> > > corrupting your modelist.
> > 
> > It's still all black.
> 
> Ok it looks like i was corrupting the modelist. The following should take 
> care of your VAIO, but i haven't tested the failure case as Tobias is away 
> this weekend.

I merged this version of the patch now. Still needs some x86-64 testing
I guess (any volunteers?), although I don't expect much trouble
because the early boot code is very similar.

-Andi

> 

Re: [PATCH] Don't probe for DDC on VBE1.2

[Zwane Mwaikambo]

On Sun, 18 Feb 2007, Andi Kleen wrote:

> On Saturday 17 February 2007 09:35, Zwane Mwaikambo wrote:
> > On Fri, 16 Feb 2007, Andrew Morton wrote:
> > 
> > > On Fri, 16 Feb 2007 06:39:45 -0800 (PST) Zwane Mwaikambo <zwane@infradead.org> wrote:
> > > 
> > > > On Thu, 15 Feb 2007, Andrew Morton wrote:
> > > > 
> > > > > It's not an X problem - the screen is black immediately upon loading the
> > > > > kernel.
> > > > > 
> > > > > But I guess you knew that and you're just after display info:
> > > > > http://userweb.kernel.org/~akpm/Xorg.0.log.txt
> > > > 
> > > > Thanks, the X log told me your VBE version. I tried to reproduce it on my 
> > > > thinkpad which seems to have a very similar video setup to no avail, Could 
> > > > you test the following on the VAIO? If this isn't the case, i suspect i'm 
> > > > corrupting your modelist.
> > > 
> > > It's still all black.
> > 
> > Ok it looks like i was corrupting the modelist. The following should take 
> > care of your VAIO, but i haven't tested the failure case as Tobias is away 
> > this weekend.
> 
> I merged this version of the patch now. Still needs some x86-64 testing
> I guess (any volunteers?), although I don't expect much trouble
> because the early boot code is very similar.

I tested the x86_64 VBE3 case (similar to Andrew's VAIO), so we just need 
a VBE1.2 on x86_64 test.

Thanks,
	Zwane

Re: [PATCH] Don't probe for DDC on VBE1.2

[Andi Kleen]

> I tested the x86_64 VBE3 case (similar to Andrew's VAIO), so we just need 
> a VBE1.2 on x86_64 test.

Does this mean you want to have an updated patch or not? 

-Andi

Re: [PATCH] Don't probe for DDC on VBE1.2

[Zwane Mwaikambo]

On Mon, 19 Feb 2007, Andi Kleen wrote:

> 
> > I tested the x86_64 VBE3 case (similar to Andrew's VAIO), so we just need 
> > a VBE1.2 on x86_64 test.
> 
> Does this mean you want to have an updated patch or not? 

Nope, i'm happy with the last patch i sent (below to reconfirm).

Thanks

Index: linux-2.6.20-mm1/arch/i386/boot/video.S
===================================================================
RCS file: /home/cvsroot/linux-2.6.20-mm1/arch/i386/boot/video.S,v
retrieving revision 1.1.1.1
diff -u -p -B -r1.1.1.1 video.S
--- linux-2.6.20-mm1/arch/i386/boot/video.S	15 Feb 2007 17:35:57 -0000	1.1.1.1
+++ linux-2.6.20-mm1/arch/i386/boot/video.S	17 Feb 2007 08:29:11 -0000
@@ -571,6 +571,16 @@ setr1:	lodsw
 	jmp	_m_s
 
 check_vesa:
+#ifdef CONFIG_FIRMWARE_EDID
+	leaw	modelist+1024, %di
+	movw	$0x4f00, %ax
+	int	$0x10
+	cmpw	$0x004f, %ax
+	jnz	setbad
+	
+	movw	4(%di), %ax
+	movw	%ax, vbe_version
+#endif
 	leaw	modelist+1024, %di
 	subb	$VIDEO_FIRST_VESA>>8, %bh
 	movw	%bx, %cx			# Get mode information structure
@@ -1945,6 +1955,9 @@ store_edid:
 	rep
 	stosl
 
+	cmpw	$0x0200, vbe_version		# only do EDID on >= VBE2.0
+	jl	no_edid
+
 	pushw   %es				# save ES
 	xorw    %di, %di                        # Report Capability
 	pushw   %di
@@ -1987,6 +2000,7 @@ do_restore:	.byte	0	# Screen contents al
 svga_prefix:	.byte	VIDEO_FIRST_BIOS>>8	# Default prefix for BIOS modes
 graphic_mode:	.byte	0	# Graphic mode with a linear frame buffer
 dac_size:	.byte	6	# DAC bit depth
+vbe_version:	.word	0	# VBE bios version
 
 # Status messages
 keymsg:		.ascii	"Press <RETURN> to see video modes available, "
Index: linux-2.6.20-mm1/arch/x86_64/boot/video.S
===================================================================
RCS file: /home/cvsroot/linux-2.6.20-mm1/arch/x86_64/boot/video.S,v
retrieving revision 1.1.1.1
diff -u -p -B -r1.1.1.1 video.S
--- linux-2.6.20-mm1/arch/x86_64/boot/video.S	15 Feb 2007 17:36:18 -0000	1.1.1.1
+++ linux-2.6.20-mm1/arch/x86_64/boot/video.S	17 Feb 2007 08:29:11 -0000
@@ -571,6 +571,16 @@ setr1:	lodsw
 	jmp	_m_s
 
 check_vesa:
+#ifdef CONFIG_FIRMWARE_EDID
+	leaw	modelist+1024, %di
+	movw	$0x4f00, %ax
+	int	$0x10
+	cmpw	$0x004f, %ax
+	jnz	setbad
+	
+	movw	4(%di), %ax
+	movw	%ax, vbe_version
+#endif
 	leaw	modelist+1024, %di
 	subb	$VIDEO_FIRST_VESA>>8, %bh
 	movw	%bx, %cx			# Get mode information structure
@@ -1945,6 +1955,9 @@ store_edid:
 	rep
 	stosl
 
+	cmpw	$0x0200, vbe_version		# only do EDID on >= VBE2.0
+	jl	no_edid
+
 	pushw   %es				# save ES
 	xorw    %di, %di                        # Report Capability
 	pushw   %di
@@ -1987,6 +2000,7 @@ do_restore:	.byte	0	# Screen contents al
 svga_prefix:	.byte	VIDEO_FIRST_BIOS>>8	# Default prefix for BIOS modes
 graphic_mode:	.byte	0	# Graphic mode with a linear frame buffer
 dac_size:	.byte	6	# DAC bit depth
+vbe_version:	.word	0	# VBE bios version
 
 # Status messages
 keymsg:		.ascii	"Press <RETURN> to see video modes available, "