From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thierry Reding Subject: Re: [RFC v2 5/5] drm/i915: Use generic HDMI infoframe helpers Date: Thu, 6 Dec 2012 17:02:14 +0100 Message-ID: <20121206160214.GA13614@avionic-0098.adnet.avionic-design.de> References: <1354725944-1862-1-git-send-email-thierry.reding@avionic-design.de> <1354725944-1862-6-git-send-email-thierry.reding@avionic-design.de> <20121206141631.GU11556@phenom.ffwll.local> <20121206142333.GA15982@avionic-0098.adnet.avionic-design.de> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============1827058764==" Return-path: Received: from moutng.kundenserver.de (moutng.kundenserver.de [212.227.126.186]) by gabe.freedesktop.org (Postfix) with ESMTP id 62476E6904 for ; Thu, 6 Dec 2012 08:02:18 -0800 (PST) In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dri-devel-bounces+sf-dri-devel=m.gmane.org@lists.freedesktop.org Errors-To: dri-devel-bounces+sf-dri-devel=m.gmane.org@lists.freedesktop.org To: Daniel Vetter Cc: dri-devel@lists.freedesktop.org List-Id: dri-devel@lists.freedesktop.org --===============1827058764== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="sm4nu43k4a2Rpi4c" Content-Disposition: inline --sm4nu43k4a2Rpi4c Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Dec 06, 2012 at 04:57:27PM +0100, Daniel Vetter wrote: > On Thu, Dec 6, 2012 at 3:23 PM, Thierry Reding > wrote: > >> > - /* sdvo spec says that the ecc is handled by the hw, and it look= s like > >> > - * we must not send the ecc field, either. */ > >> > - memcpy(sdvo_data, &avi_if, 3); > >> > - sdvo_data[3] =3D avi_if.checksum; > >> > >> This difference between how we need to send the infoframe to the hw > >> between sdvo (without ecc field present) and native hdmi (ecc field > >> present, but still computed by the hw) seems to have been lost. On a q= uick > >> read from your infoframe packer it looks like the ecc field isn't part= of > >> the packed infoframe, so this patch would break native hdmi ports (in = the > >> intel_hdmi.c file). > > > > Actually this ECC field seems to be something specific to Intel > > hardware. It doesn't appear in the HDMI specification nor in CEA-861-D. > > So it the binary infoframe representation doesn't contain it, therefore > > it should be handled by the respective drivers. So in fact the code > > should be working fine for HDMI and SDVO, since for the HDMI ports I > > explicitly left the fourth byte of the header empty, while for SDVO, the > > checksum is the one as computed by hdmi_avi_infoframe_pack(), which is > > at byte 3 and therefore matches the previous code. >=20 > Oh dear, I've failed to read the patch correctly and totally missed > the new intel_dip_pack function and assorted logic changes. Sorry for > the confusion. At first I thought to split that out in a separate patch but then decided it wasn't worth the trouble. But there's always the possibility that I've broken things horribly here since the patch is rather messy, so it's good that you look closely and some testing will certainly be good to validate that things still work as before. Thierry --sm4nu43k4a2Rpi4c Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.19 (GNU/Linux) iQIcBAEBAgAGBQJQwMGGAAoJEN0jrNd/PrOhCzwP/irbdsiysylvwAsQUt5cG39f CVJvgkmlhpX5a0NhtUF0/9sRQJNisuE+l994frBuWgksRriYLod3/J3mwu3iDue+ IWHOMaQVhQRifXj0vbS5AzzWMQ7stFLEvZWA+itcPYWOzkL67cHDrtu36FPVrFoR FlYv38gmu5b//sEhjrIQtKTSM0UADEOqUTlJtlp21QtRs1PVYqLPl3hm/sUG/x9O gcBXiFzH3/uptJAHC6tO2ngQIJdHZXuKBGlxly5g54h9Tg1cO68reZjMf9S73+h0 +fc5vchpZq7Zm9Zu1hmFZ2SKM7KCun0oZlKH8QvgtRhYEiGVSq1w3YyTXnzbLjev Ap35CxvtD1M4IqjojMh/T+kOwFfNvAP1CcWJI/ngy9B/EllM3qS0xPGK5rza1XHC qGIf6mYCZMK17jC1xMkpmfMMWyeOFksRvrt/wW6smXlkDilFH9WKC7bwT+Jh80DX zpVneF91+3qMCTYEM0oW0MbaKT+zk6x2WfrOaa9M+YdypXX/H3im+35wxwBuT38j Zy4pFDf8eDdPSedgdLWqBtMRGz+iPMzN1Tq17jlZSfT0cVChAv3qS4I2Zp9dHkYt nwJIJbqbiM0SAxDkGtWWO/qOx/RLMQkBnQ0+42BFNDtElSWWX879umXAQXWsqPfo EUop4wPDGahL9CviQkjH =MUWg -----END PGP SIGNATURE----- --sm4nu43k4a2Rpi4c-- --===============1827058764== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/dri-devel --===============1827058764==--