From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ivaylo Dimitrov Subject: Re: [PATCH 1/2] ARM: omapfb: add coherent dma memory support Date: Sun, 05 Jan 2014 16:16:54 +0200 Message-ID: <52C96956.7040803@gmail.com> References: <1388409550-10720-1-git-send-email-tomi.valkeinen@ti.com> <1388409550-10720-2-git-send-email-tomi.valkeinen@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-ea0-f178.google.com ([209.85.215.178]:50366 "EHLO mail-ea0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751139AbaAEORT (ORCPT ); Sun, 5 Jan 2014 09:17:19 -0500 In-Reply-To: <1388409550-10720-2-git-send-email-tomi.valkeinen@ti.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Tomi Valkeinen , Ivaylo Dimitrov , Vaibhav Hiremath , linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-fbdev@vger.kernel.org Cc: Tony Lindgren On 30.12.2013 15:19, Tomi Valkeinen wrote: > The omapfb driver uses dma_alloc to reserve memory for the framebuffers. > However, on some use cases, even when CMA is in use, it's quite probable > that omapfb fails to allocate the fb, either due to not enough free dma > memory, fragmented dma memory, or CMA failing to make enough contiguous > space. > > This patch adds a kernel cmdline parameter 'omapfb_vram' which can be > used to give the size of a memory area reserved exclusively for omapfb, > and optionally a physical address where the memory area is reserved. > > The memory area is reserved with memblock, and assigned to omapfb with > dma_declare_coherent_memory. The dma_alloc function will first try to > allocate the fb from the coherent memory area, and if that fails, it'll > use the normal method of allocation. > > Signed-off-by: Tomi Valkeinen > Cc: Ivaylo Dimitrov > --- > arch/arm/mach-omap2/common.c | 1 + > arch/arm/mach-omap2/common.h | 2 ++ > arch/arm/mach-omap2/fb.c | 77 +++++++++++++++++++++++++++++++++++++++++++- > 3 files changed, 79 insertions(+), 1 deletion(-) > Tested on Nokia N900 with Maemo5 and linux 3.13-rc6