Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1423219AbXBPE5U (ORCPT ); Thu, 15 Feb 2007 23:57:20 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1423230AbXBPE5U (ORCPT ); Thu, 15 Feb 2007 23:57:20 -0500 Received: from smtp.osdl.org ([65.172.181.24]:49803 "EHLO smtp.osdl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1423219AbXBPE5T (ORCPT ); Thu, 15 Feb 2007 23:57:19 -0500 Date: Thu, 15 Feb 2007 20:56:58 -0800 From: Andrew Morton To: Zwane Mwaikambo Cc: Linux Kernel , Andi Kleen , Tobias Hain , "H. Peter Anvin" Subject: Re: [PATCH] Don't probe for DDC on VBE1.2 Message-Id: <20070215205658.56096f97.akpm@linux-foundation.org> In-Reply-To: References: X-Mailer: Sylpheed version 2.2.7 (GTK+ 2.8.17; x86_64-unknown-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1942 Lines: 60 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 > > :( > > 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 > > 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. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/