From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= Subject: Re: AVI infoframes: default aspect ratio/VIC for CEA modes Date: Thu, 21 Nov 2013 19:19:45 +0200 Message-ID: <20131121171945.GB10036@intel.com> References: <82115773F5CCE44DA5B6CE8B3878B6F027E4EDB2@FMSMSX106.amr.corp.intel.com> <20131120221155.GA24799@strange.amr.corp.intel.com> <20131120222057.GB24799@strange.amr.corp.intel.com> <82115773F5CCE44DA5B6CE8B3878B6F027E4EF4A@FMSMSX106.amr.corp.intel.com> <20131121003731.GA26262@strange.amr.corp.intel.com> <82115773F5CCE44DA5B6CE8B3878B6F027E500F6@FMSMSX106.amr.corp.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: Content-Disposition: inline In-Reply-To: <82115773F5CCE44DA5B6CE8B3878B6F027E500F6@FMSMSX106.amr.corp.intel.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces@lists.freedesktop.org Errors-To: intel-gfx-bounces@lists.freedesktop.org To: "Gohad, Tushar" Cc: "intel-gfx@lists.freedesktop.org" , "dri-devel@lists.freedesktop.org" List-Id: intel-gfx@lists.freedesktop.org On Thu, Nov 21, 2013 at 02:48:55AM +0000, Gohad, Tushar wrote: > > On Wed, Nov 20, 2013 at 11:45:03PM +0000, Gohad, Tushar wrote: > > > > > On Wed, Nov 20, 2013 at 09:48:26PM +0000, Gohad, Tushar wrote: > > > > > > Folks, > > > > > > > > > > > > When filling in an HDMI AVI infoframe, how does one correctly > > > > > > determine the "default" picture aspect ratio (and VIC) for CEA > > > > > > modes that support multiple (4:3 and 16:9) aspect ratios. > > > > > > 720x576p for example, corresponds to VIC 17 or 18: > > > > > > > > > > > > /* 17 - 720x576@50Hz */ > > > > > > { DRM_MODE("720x576", DRM_MODE_TYPE_DRIVER, 27000, 720, > > > > 732, > > > > > > 796, 864, 0, 576, 581, 586, 625, 0, > > > > > > DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC), > > > > > > .vrefresh =3D 50, }, > > > > > > /* 18 - 720x576@50Hz */ > > > > > > { DRM_MODE("720x576", DRM_MODE_TYPE_DRIVER, 27000, 720, > > > > 732, > > > > > > 796, 864, 0, 576, 581, 586, 625, 0, > > > > > > DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC), > > > > > > .vrefresh =3D 50, }, > > > > > > > > > > > > Should the "picture aspect ratio" information be derived from > > > > > > sink EDID (from detailed/cvt/standard timings)? .. possibly in > > > > > > drm_add_edid_modes() and store the picture aspect ratio in > > > > > > drm_display_mode perhaps, for later use? Trying to get a better > > > > > > understanding of how this usually works. > > > > > > > > > > Oh no! someone finally discovered it! Yes, we are totally missing > > > > > the picture aspect ratio information from the CEA modes. It's been > > > > > on my TODO list for a couple of month but not exactly high > > > > > priority. If we want to get a stab a it, we'll review the patches > > > > > :) > > > > = > > > Thanks Damien. Sure, I can come up with something quick. Is the idea > > > then to store aspect ratio information in drm_display_mode, possibly > > > as a separate member or as a hint that's part of mode->flags? > > = > > It seems natural to extend those flags to describe the picture aspect r= atio (that > > why dri-devel is in Cc., touching core DRM). > = > Cc: dri-devel > = > To start with we can use a single bit in drm_display_mode->flags to disti= nguish 16:9 vs 4:3. I must admit I haven't really looked into the matter, but do we actually need any mode bits? Would it be enoguh to just have a property that allows the user to specify the picture aspect ratio? -- = Ville Syrj=E4l=E4 Intel OTC