From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754651AbaFQKBP (ORCPT ); Tue, 17 Jun 2014 06:01:15 -0400 Received: from cantor2.suse.de ([195.135.220.15]:47249 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750778AbaFQKBN (ORCPT ); Tue, 17 Jun 2014 06:01:13 -0400 Date: Tue, 17 Jun 2014 12:01:09 +0200 Message-ID: From: Takashi Iwai To: Benjamin Herrenschmidt Cc: Tomi Valkeinen , Jean-Christophe Plagniol-Villard , Cedric Le Goater , linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] offb: Fix little-endian support In-Reply-To: <1402962847.7661.82.camel@pasglop> References: <1400073709-15012-1-git-send-email-tiwai@suse.de> <1402904135.7661.34.camel@pasglop> <1402962847.7661.82.camel@pasglop> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI/1.14.6 (Maruoka) FLIM/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL/10.8 Emacs/24.3 (x86_64-suse-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org At Tue, 17 Jun 2014 09:54:07 +1000, Benjamin Herrenschmidt wrote: > > On Mon, 2014-06-16 at 17:35 +1000, Benjamin Herrenschmidt wrote: > > > I somewhat doubt that this (and 5:5:5) actually work, do they ? the > > green gets split into two separate fields, which we can't express > > properly here... > > So the conclusion of further investigation is: > > - The right fix is to fix qemu to flip endian > > - There's an open discussion as to whether qemu could do it > automatically when the guest endian changes on powerpc as a quick fix, > the long run approach is to have a register to control it, I'm working > on it. offb can then "learn" to flick it like it does the palette hack > today. > > - If we want to ever support foreign endian offb with X, we need to do > things a bit differently based on the foreign endian bit that is already > there. > > - We must revert the existing cmap swap patch from the kernel, it's > broken and will break things when we fix qemu (and breaks with real HW > in LE mode). I've sent a revert request to Linus and CC'ed stable. Yeah, I agree. Both the current palette fix and my patch are really wrong band-aiding. (Though, the issue in X is rather a problem of X itself. X should work with the tweaked RGB offsets.) thanks, Takashi From mboxrd@z Thu Jan 1 00:00:00 1970 From: Takashi Iwai Date: Tue, 17 Jun 2014 10:01:09 +0000 Subject: Re: [PATCH] offb: Fix little-endian support Message-Id: List-Id: References: <1400073709-15012-1-git-send-email-tiwai@suse.de> <1402904135.7661.34.camel@pasglop> <1402962847.7661.82.camel@pasglop> In-Reply-To: <1402962847.7661.82.camel@pasglop> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Benjamin Herrenschmidt Cc: Tomi Valkeinen , Jean-Christophe Plagniol-Villard , Cedric Le Goater , linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org At Tue, 17 Jun 2014 09:54:07 +1000, Benjamin Herrenschmidt wrote: > > On Mon, 2014-06-16 at 17:35 +1000, Benjamin Herrenschmidt wrote: > > > I somewhat doubt that this (and 5:5:5) actually work, do they ? the > > green gets split into two separate fields, which we can't express > > properly here... > > So the conclusion of further investigation is: > > - The right fix is to fix qemu to flip endian > > - There's an open discussion as to whether qemu could do it > automatically when the guest endian changes on powerpc as a quick fix, > the long run approach is to have a register to control it, I'm working > on it. offb can then "learn" to flick it like it does the palette hack > today. > > - If we want to ever support foreign endian offb with X, we need to do > things a bit differently based on the foreign endian bit that is already > there. > > - We must revert the existing cmap swap patch from the kernel, it's > broken and will break things when we fix qemu (and breaks with real HW > in LE mode). I've sent a revert request to Linus and CC'ed stable. Yeah, I agree. Both the current palette fix and my patch are really wrong band-aiding. (Though, the issue in X is rather a problem of X itself. X should work with the tweaked RGB offsets.) thanks, Takashi