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 <[EMAIL PROTECTED]> 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 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
