From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 572CD606A330 for ; Tue, 10 Nov 2026 13:34:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=WdkxDLoj Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A85D810E1C2; Tue, 10 Nov 2026 13:34:47 +0000 (UTC) Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by gabe.freedesktop.org (Postfix) with ESMTPS id CA00210E1C2 for ; Tue, 10 Nov 2026 13:34:41 +0000 (UTC) Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 8E617437E7; Tue, 10 Nov 2026 13:34:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 47F8C1F008A1; Tue, 10 Nov 2026 13:34:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794317681; bh=i1rfpHQXF1FfFJ1XShiSkA/h4aESzgAcBmkFaN9G28E=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=WdkxDLoj2qfymHJOMGmsTfHPOXfgc7EKM/iRnXLbgzrujT6D7GTqb49GE8HNkBIY6 Qgl9L6D4bZ7/utWB87KTmvpN9EEAS9lgXB3UlTBgy0dJ7VokL8ICakO1e9UpMv7U+C wyTOg8YvGBZm/bPm67ROmFkld0rZdSnFubM8JypAnFSoGJ3m7VbJEZOBNm2NDUpt2j N0S8HTCl0Z5lpWY/PpOOxQlOLDF9bTjSKs0tghzMCkS/Y31jd+6wzcOsD3JDQo+PMl BnXnLGTUq1hbRirsqv65eh9kUiU6TcED0hspJ4T7cJ+0Rs6feVp4HNU5wvPXXBSjSz HO/9c4VSdtCDA== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH 2/3] drm/amd/display: Wait up to 1 s for slow sinks in FRL link training To: =?utf-8?b?QW5kcnplaiBQacSFdHlzemVr?= Cc: dri-devel@lists.freedesktop.org In-Reply-To: <20261110130956.160024-3-andrzej.piatyszek@gmail.com> References: <20261110130956.160024-1-andrzej.piatyszek@gmail.com> <20261110130956.160024-3-andrzej.piatyszek@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Tue, 10 Nov 2026 13:34:40 +0000 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: sashiko-reviews@lists.linux.dev Sender: "dri-devel" X-Spam-Status: No, score=-10.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 X-Archived-By: Thank you for your contribution! Sashiko AI review found 1 potential issue to consider: - [Medium] drm/amd/display: unconditional 1s LTS:3 timeout violates HDMI T_FLT spec -- commit 2cb267c6df8cc9565556b092b803e0c5c55db242 Author: Andrzej Pi=C4=85tyszek drm/amd/display: Wait up to 1 s for slow sinks in FRL link training This commit increases the FRL link training state 3 (LTS:3) polling timeout in hdmi_frl_perform_link_training() to 1 second across all link rates to accommodate slow HDMI sinks. > diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_hdmi_frl.= c b/drivers/gpu/drm/amd/display/dc/link/protocols/link_hdmi_frl.c > index 78e62bfec49c7..97b2b9b74cc71 100644 > --- a/drivers/gpu/drm/amd/display/dc/link/protocols/link_hdmi_frl.c > +++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_hdmi_frl.c > @@ -612,10 +612,13 @@ static enum link_result hdmi_frl_perform_link_train= ing(struct ddc_service *ddc_s > =20 > FRL_INFO("FRL LINK TRAINING: Poll for FLT_UPDATE.\n"); > /*LTS:3: Start Link Training*/ > - /*Start FLT Timer =3D 200 ms, or 300ms if link rate >=3D 16Gbps*/ > + /* > + * Start FLT Timer. Some sinks need longer than the nominal 200 ms > + * (300 ms at 16 Gbps and above) to answer an LTP request, so wait > + * up to 1 s before giving up on this rate. > + */ > num_polls =3D 0; > - if (link_settings->frl_link_rate >=3D HDMI_FRL_LINK_RATE_16GBPS) > - poll_timeout_ns =3D 320 * 1000 * 1000; > + poll_timeout_ns =3D 1000 * 1000 * 1000; [Severity: Medium] Does setting poll_timeout_ns to 1 second unconditionally for all sinks break HDMI 2.1/2.2 link layer compliance testing when test_req.fields.FLT_NO_TIME= OUT is 0? The HDMI specification limits the LTS:3 T_FLT timer to 200 ms nominal (220 = ms max) for rates below 16 Gbps and 300 ms nominal (320 ms max) for 16 Gbps and above. Commits f38686268b0d ("drm/amd/display: Fix HDMI2.2 LT timeout duration"), 536ad3cf1871 ("drm/amd/display: Fix HDMI FRL FFE compliance tes= t") and 007834be6760 ("drm/amd/display: Adjust HDMI FRL LT timeout") specifical= ly tuned poll_timeout_ns to 220 ms and 320 ms so the elapsed time in LTS:3 does not exceed the spec-defined limits during compliance tests. Could the 1 se= cond timeout be applied only to affected displays via an EDID quirk instead? --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261110130956.1600= 24-1-andrzej.piatyszek@gmail.com?part=3D2