From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Anholt Subject: Re: [PATCH] drm/vc4: Use 16bpp by default for the fbdev buffer Date: Wed, 06 Mar 2019 09:32:01 -0800 Message-ID: <87ef7jkiy6.fsf@anholt.net> References: <20190306140245.21973-1-maxime.ripard@bootlin.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============0837905499==" Return-path: Received: from anholt.net (anholt.net [50.246.234.109]) by gabe.freedesktop.org (Postfix) with ESMTP id 9D5596E13E for ; Wed, 6 Mar 2019 17:32:05 +0000 (UTC) In-Reply-To: <20190306140245.21973-1-maxime.ripard@bootlin.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Cc: eben@raspberrypi.org, Maxime Ripard , dri-devel@lists.freedesktop.org, Paul Kocialkowski , Sean Paul , Thomas Petazzoni , linux-arm-kernel@lists.infradead.org List-Id: dri-devel@lists.freedesktop.org --===============0837905499== Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha512; protocol="application/pgp-signature" --=-=-= Content-Type: text/plain Maxime Ripard writes: > The preferred bpp for the fbdev emulation buffer has been 32 so far, which > means that by default we will allocate an 8MB buffer with a 1920x1080 > resolution. > > Worse this memory will be allocated from the CMA pool, and will never be > freed even if we don't use the fbdev emulation. Therefore, reducing it is a > big deal, and switching to 16bpp by default will gain us around 4MB at > 1920x1080, while keeping decent color depth. And users still have the > option to switch to 32bpp using the kernel command line. Reviewed-by: Eric Anholt This matches the defaults used by the bcm2708 fbdev driver that we're trying to get people to switch off of. --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCgAdFiEE/JuuFDWp9/ZkuCBXtdYpNtH8nugFAlyABBEACgkQtdYpNtH8 nugm4A/9GCfu8WwfhqZk+5d9PLe/9jFpg6iAQ1GaKp44Z/tLa4GAKRwifbX1PqiI tqBydo/K00ggn5iZOnstJXS3TaSYf+mdXcu+R/J/eo7fVeMvKbFSyJ2PF3bI17co yjo/YR4B+ojeFW3AOas4c2MPp7tZGhjVWenPQ9Nipd/Dnw+Aeh1996TNprlXySMw 7gHRWeIkfZ5GIIvG6vytcUVWcBdQSWSA528n9MnO+m55byRIS0NCVYTwkb6FhoqA IfUj2Jvo86rlXKT6Ep7baiOr89J/Um1SAq/qFLr7tqtwe6eNoQ8t04O0h7Q53EfW YhFyFzPLmMBGHZJ9IoUYh3lwlAdic5TtwptnXtWcdIPbAjIDmnV7dFVN7GK8Gowx 0hebGEKPlvCyH756GWv+hRLTAeUHOvazdguBfFW2mk8qbbLP1KM4zuL/jCTp3AwD ngB3EVY0Cp+9RLimcWQhORfJHn+g9x958+J5pqQlOEjQwVpZ43NOiadFzidgus05 qcZNYMYcEVYEBTHrGWAGN8SxhkV0eiCOVf1KcUUeZFzTqvrsiOLB5wkFYqFXFaH7 JLrsdxhHQ32c/Eb8L0ghkoGpypOWP2kFb72ITsKe7qVeJ7NLN9Lp3I6HHddTh/Z1 tiqjvUCLXVE8IEzMwbnvHBeANBWVp5EhNSLLcC9kq+wTtEoLzjk= =75dA -----END PGP SIGNATURE----- --=-=-=-- --===============0837905499== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Content-Disposition: inline X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KZHJpLWRldmVs IG1haWxpbmcgbGlzdApkcmktZGV2ZWxAbGlzdHMuZnJlZWRlc2t0b3Aub3JnCmh0dHBzOi8vbGlz dHMuZnJlZWRlc2t0b3Aub3JnL21haWxtYW4vbGlzdGluZm8vZHJpLWRldmVs --===============0837905499==--