From mboxrd@z Thu Jan 1 00:00:00 1970 From: Keith Packard Subject: Re: [PATCH 12/16] drm/915: fix relaxed tiling on gen2: tile height Date: Sun, 15 May 2011 14:58:26 -0700 Message-ID: References: <1305235044-9159-1-git-send-email-chris@chris-wilson.co.uk> <1305235044-9159-13-git-send-email-chris@chris-wilson.co.uk> <20110515204340.GB3510@viiv.ffwll.ch> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============0970380984==" Return-path: Received: from keithp.com (home.keithp.com [63.227.221.253]) by gabe.freedesktop.org (Postfix) with ESMTP id C3CDF9E7BA for ; Sun, 15 May 2011 14:58:31 -0700 (PDT) In-Reply-To: <20110515204340.GB3510@viiv.ffwll.ch> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org Errors-To: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org To: Daniel Vetter Cc: Daniel Vetter , intel-gfx@lists.freedesktop.org List-Id: intel-gfx@lists.freedesktop.org --===============0970380984== Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha1; protocol="application/pgp-signature" --=-=-= Content-Transfer-Encoding: quoted-printable On Sun, 15 May 2011 22:43:41 +0200, Daniel Vetter wrote: > No problem for old userspace. This only changes the number of rows from 32 > to 16. This value is used in the kernel to align buffers correctly, i.e. > it will save perhaps a tiny bit of gtt. Userspace on the other hand > assumed only 8 rows, which lead to underallocating it the last tile > row. I have this vague memory of some problem in the past with tiling and old user space for Gen2 hardware. I assume that old user space will just do bad things, but that there's nothing the kernel can do to fix it, right? The requirement here is that kernel changes not break user space, even if the kernel was just masking a user-space bug. If that isn't true for any old user space version, then this should be fine. > So this patch is more documentation of actual hw behaviour than anything > else - hopefully getting rid of gen2 tiling confusion once and for all. Cool. Thanks for the clarification. =2D-=20 keith.packard@intel.com --=-=-= Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iD8DBQFN0EyCQp8BWwlsTdMRAlcgAJ9hCPByHzETCdhxVEi+nZ79XKQiKACdHUOa gAZeKKMd4TE0sSBQ8k8wegw= =3XVm -----END PGP SIGNATURE----- --=-=-=-- --===============0970380984== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx --===============0970380984==--