Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761390Ab2FVLGs (ORCPT ); Fri, 22 Jun 2012 07:06:48 -0400 Received: from h9.dl5rb.org.uk ([81.2.74.9]:56562 "EHLO h5.dl5rb.org.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1758179Ab2FVLGq (ORCPT ); Fri, 22 Jun 2012 07:06:46 -0400 Date: Fri, 22 Jun 2012 12:06:19 +0100 From: Ralf Baechle To: Arnaud Patard Cc: Huacai Chen , linux-mips@linux-mips.org, linux-kernel@vger.kernel.org, Fuxin Zhang , Zhangjin Wu , Huacai Chen , Hongliang Tao , Hua Yan , dri-devel@lists.freedesktop.org Subject: Re: [PATCH V3 11/16] drm/radeon: Make radeon card usable for Loongson. Message-ID: <20120622110619.GA18249@linux-mips.org> References: <1340334073-17804-1-git-send-email-chenhc@lemote.com> <1340334073-17804-12-git-send-email-chenhc@lemote.com> <87txy3sn20.fsf@lebrac.rtp-net.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87txy3sn20.fsf@lebrac.rtp-net.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1450 Lines: 32 On Fri, Jun 22, 2012 at 11:39:19AM +0200, Arnaud Patard wrote: > > --- a/drivers/gpu/drm/drm_vm.c > > +++ b/drivers/gpu/drm/drm_vm.c > > @@ -62,7 +62,7 @@ static pgprot_t drm_io_prot(uint32_t map_type, struct vm_area_struct *vma) > > tmp = pgprot_writecombine(tmp); > > else > > tmp = pgprot_noncached(tmp); > > -#elif defined(__sparc__) || defined(__arm__) > > +#elif defined(__sparc__) || defined(__arm__) || defined(__mips__) > > tmp = pgprot_noncached(tmp); > > btw, would it be a good idea to use uncached accelerated instead ? Not unconditionally. Only some MIPS cores support uncached accelerated. Basically you can only assume that cache modes 2 (uncached) (3 cachable non-coherent) are supported. On a SMP system use of 2 and 3 may be unwise (SGI IP27 and IP35 may throw obscure exceptions to indicate their dislike of these.) and on multi-processor systems there is mode 5, which is cachable coherent. The necessary logic is too complex to got into drm_io_prot() which already is an #ifdef mess anyway so that function should be changed to call some sort of architecutre specific hook so that function should be changed to call some sort of architecture specific hook... Ralf -- 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/