From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752487AbdFUIGi (ORCPT ); Wed, 21 Jun 2017 04:06:38 -0400 Received: from mail.netline.ch ([148.251.143.178]:55594 "EHLO netline-mail3.netline.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751038AbdFUIGd (ORCPT ); Wed, 21 Jun 2017 04:06:33 -0400 X-Greylist: delayed 414 seconds by postgrey-1.27 at vger.kernel.org; Wed, 21 Jun 2017 04:06:32 EDT Subject: Re: [PATCH 01/11] drm/fb-helper: do a generic fb_setcmap helper in terms of crtc .gamma_set To: Peter Rosin , Philippe Cornu , =?UTF-8?Q?Christian_K=c3=b6nig?= , Yannick Fertre , Gerd Hoffmann , Daniel Vetter , Alex Deucher , Dave Airlie , Vincent Abriou , Ben Skeggs References: <1497986735-14418-1-git-send-email-peda@axentia.se> <1497986735-14418-2-git-send-email-peda@axentia.se> <20170621073804.akyg4rxvoavjjt2v@phenom.ffwll.local> From: =?UTF-8?Q?Michel_D=c3=a4nzer?= Cc: linux-kernel@vger.kernel.org, amd-gfx@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, nouveau@lists.freedesktop.org, dri-devel@lists.freedesktop.org, virtualization@lists.linux-foundation.org Message-ID: Date: Wed, 21 Jun 2017 16:59:31 +0900 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.0 MIME-Version: 1.0 In-Reply-To: <20170621073804.akyg4rxvoavjjt2v@phenom.ffwll.local> Content-Type: text/plain; charset=utf-8 Content-Language: en-CA Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 21/06/17 04:38 PM, Daniel Vetter wrote: > On Tue, Jun 20, 2017 at 09:25:25PM +0200, Peter Rosin wrote: >> This makes the redundant fb helpers .load_lut, .gamma_set and .gamma_get >> totally obsolete. >> >> I think the gamma_store can end up invalid on error. But the way I read >> it, that can happen in drm_mode_gamma_set_ioctl as well, so why should >> this pesky legacy fbdev stuff be any better? >> >> drm_fb_helper_save_lut_atomic justs saves the gamma lut for later. However, >> it saves it to the gamma_store which should already be up to date with what >> .gamma_get would return and is thus a nop. So, zap it. > > Removing drm_fb_helper_save_lut_atomic should be a separate patch I > think. > >> Signed-off-by: Peter Rosin [...] >> @@ -1167,50 +1150,6 @@ void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper, >> } >> EXPORT_SYMBOL(drm_fb_helper_set_suspend_unlocked); >> >> -static int setcolreg(struct drm_crtc *crtc, u16 red, u16 green, >> - u16 blue, u16 regno, struct fb_info *info) >> -{ >> - struct drm_fb_helper *fb_helper = info->par; >> - struct drm_framebuffer *fb = fb_helper->fb; >> - >> - if (info->fix.visual == FB_VISUAL_TRUECOLOR) { > > This case here seems gone, and it was also the pièce de résistance when I > tried tackling fbdev lut support. As far as I understand this stuff we do > not support FB_VISUAL_TRUECOLOR palette, and all that bitshifting here is > pointless. But I'm honestly not really clear. > > I think removing this case should also be a separate patch, and I'd very > much prefer that someone with some fbdev-clue would ack it. No need for anyone with fbdev-clue, just run fbset -i. :) fbcon uses a TRUECOLOR visual at depths > 8. > It's a pre-existing bug, but should we also try to restore the fbdev lut > in drm_fb_helper_restore_fbdev_mode_unlocked()? Would be yet another bug, > but might be relevant for your use-case. Just try to run both an fbdev > application and some kms-native thing, and then SIGKILL the native kms > app. > > But since pre-existing not really required, and probably too much effort. I suspect something like that indeed needs to be done though. E.g. killing Xorg results in fbcon continuing to use the LUT set by Xorg. -- Earthling Michel Dänzer | http://www.amd.com Libre software enthusiast | Mesa and X developer