From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benson Leung Subject: Re: [PATCH] drm/dp: only accept valid DP_TRAINING_AUX_RD_INTERVAL values Date: Fri, 2 Mar 2018 23:34:08 -0800 Message-ID: <20180303073408.GA64026@decatoncale.mtv.corp.google.com> References: <1520029558-12219-1-git-send-email-matthew.s.atwood@intel.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============0132885488==" Return-path: Received: from mail-pl0-x231.google.com (mail-pl0-x231.google.com [IPv6:2607:f8b0:400e:c01::231]) by gabe.freedesktop.org (Postfix) with ESMTPS id 25BA36E139 for ; Sat, 3 Mar 2018 07:34:12 +0000 (UTC) Received: by mail-pl0-x231.google.com with SMTP id i6-v6so6999369plt.7 for ; Fri, 02 Mar 2018 23:34:12 -0800 (PST) In-Reply-To: <1520029558-12219-1-git-send-email-matthew.s.atwood@intel.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: matthew.s.atwood@intel.com Cc: manasi.d.navare@intel.com, dri-devel@lists.freedesktop.org, rodrigo.vivi@intel.com List-Id: dri-devel@lists.freedesktop.org --===============0132885488== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="G4iJoqBmSsgzjUCe" Content-Disposition: inline --G4iJoqBmSsgzjUCe Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi Matt, On Fri, Mar 02, 2018 at 02:25:58PM -0800, matthew.s.atwood@intel.com wrote: > From: Matt Atwood >=20 > For panels that do not follow Display Port specifications mask off invalid > values for DP_TRAINING_AUX_RD_INTERVAL. Specification lists acceptable > values 0-4 all other values are reserved and bit 7 of DPCD 0x0000e > describes another feature. Currently the code uses all of DPCD 0x0000e and > can cause max wait for 1024 ms instead of 16 ms as specified table 2-158. > This address is read for both clock recovery and channel equalization. >=20 > Signed-off-by: Matt Atwood Tested-by: Benson Leung I tested this patch on that particularly problematic panel, with the out of spec value of 9. With the masking, the panel link trains successfully. Thanks! --=20 Benson Leung Staff Software Engineer Chrome OS Kernel Google Inc. bleung@google.com Chromium OS Project bleung@chromium.org --G4iJoqBmSsgzjUCe Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEE6gYDF28Li+nEiKLaHwn1ewov5lgFAlqaT/AACgkQHwn1ewov 5liKdg//Z1CEGP4HXh1EfNzO7pvYxW/n7Gg8ULQXdnAPRUBilAnXNa8Byd0LSknw SGq3eZ27QCJVFr1Va5C01hZHQAUJSSFIDRvSsOFAPik5FIbxQ4Z0FXZ34Wk7GezM hzyHCclkFryA/qHjKgdy7fEgSNQeIMxk5Wmf8w8nSaQA6QtKJihvxTwUmO+E5POV YHdFBf8BCVnsWS2b0omlifDk0gx2yoFWJWB+gTBP16hUrkcO2i23fZIREP8GyJr8 9iIJFyJ3tzoS3HNF04ou6nXAlQSyQ3lNxKDKSOH9kSZpDC1Eh8M/EcvP8i0tqhoA m5uunnTg2vIZCkhEDFZfj1LRAr2kS6RbxZ6RSchI70cD6D9x5+JLGd4aiVoHz20C dxG52oUn38fSZ6shghV+Uk7DT4aN/2RHa0tJNWZS7j0GbYakizYUL3O4wWXXtcOH RhwYDlcqkg+zsCSWvuJJvRsBS/Mplx4TkabgUDfxPcXwMvgV/ayT428CIzxtAbw5 0RRqIL79mp+fiFemgB/8PoV0rp1MdaClVe8KDI6ofeSZ12061RkYu8k5ZfkKQvvd NuwcyN5pJNeEVNHxfFlUSC2Rfb6bcfxSzzIGBOmTPx49L87wXuA8LXTQxJGYMCdT XPTRhWFYrbsLfKZRAoQKI0SdJVH93AVgyq9K+RtqQ2xJXxrX4PM= =Ei3y -----END PGP SIGNATURE----- --G4iJoqBmSsgzjUCe-- --===============0132885488== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Content-Disposition: inline X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KZHJpLWRldmVs IG1haWxpbmcgbGlzdApkcmktZGV2ZWxAbGlzdHMuZnJlZWRlc2t0b3Aub3JnCmh0dHBzOi8vbGlz dHMuZnJlZWRlc2t0b3Aub3JnL21haWxtYW4vbGlzdGluZm8vZHJpLWRldmVsCg== --===============0132885488==--