From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lauri Kasanen Subject: Re: [PATCH] drm/radeon: TTM must be init with cpu-visible VRAM, v2 Date: Sat, 1 Mar 2014 11:15:00 +0200 Message-ID: <20140301111500.cd313296.cand@gmx.com> References: <20140228205023.9677a7f9.cand@gmx.com> <5310E9EA.8020606@vodafone.de> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-15" Content-Transfer-Encoding: quoted-printable Return-path: Received: from mout.gmx.net (mout.gmx.net [212.227.17.22]) by gabe.freedesktop.org (Postfix) with ESMTP id 8AE7AFA948 for ; Sat, 1 Mar 2014 01:14:05 -0800 (PST) Received: from Valinor ([84.248.177.169]) by mail.gmx.com (mrgmx002) with ESMTPA (Nemesis) id 0M7pI0-1X61Lo03FY-00vRin for ; Sat, 01 Mar 2014 10:14:04 +0100 In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dri-devel-bounces@lists.freedesktop.org Errors-To: dri-devel-bounces@lists.freedesktop.org To: Dave Airlie Cc: dri-devel List-Id: dri-devel@lists.freedesktop.org On Sat, 1 Mar 2014 06:47:41 +1000 Dave Airlie wrote: > On Sat, Mar 1, 2014 at 5:56 AM, Christian K=F6nig wrote: > > Am 28.02.2014 19:50, schrieb Lauri Kasanen: > > > >> Without this, a bo may get created in the cpu-inaccessible vram. > >> Before the CP engines get setup, all copies are done via cpu memcpy. > >> > >> This means that the cpu tries to read from inaccessible memory, fails, > >> and the radeon module proceeds to disable acceleration. > >> > >> Doing this has no downsides, as the real VRAM size gets set as soon as= the > >> CP engines get init. > >> > >> This is a candidate for 3.14 fixes. > >> > >> v2: Add comment on why the function is used > >> Reviewed-by: Christian K=F6nig >> >> And I suggest to add "Cc: stable@vger.kernel.org" as well. > > Won't this create objects that are stuck in the middle of VRAM with > the new top down approach? > = > then when we go to use all the VRAM they'll be pinned in the middle? Yes, the initial pins would act like that with the top-down code. But the top-down logic is 3.15 material and still WIP. Depending on their constraints, I think I'll either add a new flag, or turn them into FIXED allocations - do they need to be at exact position foo or only at the beginning. (Christian?) So sending this fix to stable is safe, as they all use bottom-up. - Lauri