From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964824AbcHDPIt (ORCPT ); Thu, 4 Aug 2016 11:08:49 -0400 Received: from mail-wm0-f66.google.com ([74.125.82.66]:36375 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751820AbcHDPIs (ORCPT ); Thu, 4 Aug 2016 11:08:48 -0400 Date: Thu, 4 Aug 2016 17:08:43 +0200 From: Daniel Vetter To: Luc Verhaegen Cc: Noralf =?iso-8859-1?Q?Tr=F8nnes?= , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org Subject: Re: [PATCH 0/2] drm: add SimpleDRM driver Message-ID: <20160804150843.GL6232@phenom.ffwll.local> Mail-Followup-To: Luc Verhaegen , Noralf =?iso-8859-1?Q?Tr=F8nnes?= , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org References: <1470319400-14625-1-git-send-email-noralf@tronnes.org> <20160804141525.GC4256@skynet.be> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20160804141525.GC4256@skynet.be> X-Operating-System: Linux phenom 4.6.0-1-amd64 User-Agent: Mutt/1.6.0 (2016-04-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Aug 04, 2016 at 04:15:25PM +0200, Luc Verhaegen wrote: > On Thu, Aug 04, 2016 at 04:03:18PM +0200, Noralf Trønnes wrote: > > > > I have tested simpledrm on a Raspberry Pi B+ with U-boot setting up the > > framebuffer and producing this node: > > > > framebuffer@1e887000 { > > compatible = "simple-framebuffer"; > > reg = <0x1e887000 0x36c600>; > > format = "r5g6b5"; > > width = <1824>; > > height = <984>; > > stride = <3648>; > > status = "okay"; > > }; > > > > I have only tested with fbcon and modetest (XR24,RG16). > > Please do not make the same mistake as simplefb in making this purely a > rpifb. Know that you will need some power and clock management for > properly free devices that do not depend on a binary only RTOS which > does _everything_ behind our backs. > > Cfr this useless, endless and ridiculous discussion: > http://lists.infradead.org/pipermail/linux-arm-kernel/2014-August/279071.html simpledrm isn't a real driver, but only meant to be used to drive the firmware framebuffer in early boot until a real driver takes over. It's a replacement really for all the various uefi/vesa/whatever fbdev drivers. Full reliance on the firmware very much intended. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch