From patchwork Mon Aug 24 15:33:51 2026 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bethany Jamison X-Patchwork-Id: 2291213 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=lists.ubuntu.com (client-ip=185.125.189.65; helo=lists.ubuntu.com; envelope-from=kernel-team-bounces@lists.ubuntu.com; receiver=patchwork.ozlabs.org) Received: from lists.ubuntu.com (lists.ubuntu.com [185.125.189.65]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4hTFM96Sgwz1xpj for ; Tue, 25 Aug 2026 01:34:13 +1000 (AEST) Received: from localhost ([127.0.0.1] helo=lists.ubuntu.com) by lists.ubuntu.com with esmtp (Exim 4.86_2) (envelope-from ) id 1wyWgU-00028d-9o; Mon, 24 Aug 2026 15:34:02 +0000 Received: from smtp-relay-internal-0.internal ([10.131.114.225] helo=smtp-relay-internal-0.canonical.com) by lists.ubuntu.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1wyWgS-000273-Tu for kernel-team@lists.ubuntu.com; Mon, 24 Aug 2026 15:34:00 +0000 Received: from mail-yw1-f200.google.com (mail-yw1-f200.google.com [209.85.128.200]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by smtp-relay-internal-0.canonical.com (Postfix) with ESMTPS id C91873F56B for ; Mon, 24 Aug 2026 15:34:00 +0000 (UTC) Received: by mail-yw1-f200.google.com with SMTP id 00721157ae682-8200f68246dso3246497b3.1 for ; Mon, 24 Aug 2026 08:34:00 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1787585640; x=1788190440; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:to:from:x-gm-gg:x-gm-message-state:from:to :cc:subject:date:message-id:reply-to:content-type; bh=qSf9JLlk6ZqxdKNFa6e4kXYBJMdu1hvI16xKxHSemYI=; b=Bsn0Brtwn4fkWxHVDZNxUsCN/gIdnSjBWVjJYiGmpJ7LSYWruy5KUEUHBcbxxQkleu rdWQa/5SpXzf0+iQE53jzr+buO03GslSLaeYcn8/AohG9tbMyfddjnIh24yXVLuP5TFN b9DIcqoAXtlgnAnhe9la7KVzAf0wc+M4rsTRsnnOCPBdc1x9vylapaOa+ODIMNQdS/y8 gXyXc06ecCycNY4idbeMOfmNqbuWaNOdrCRrEZGc3bGCGaPoi8mntJ2KVOVS6ccD8WRb yYdxRUASpc9cQYHcE81FaQ78RxH6Be27+WKaiY76boB2UxhwyEioX30Gz9KXomP4C7fa kuEw== X-Gm-Message-State: AFuF++nwSquQsD6zJRUeRaZTofzN0ZQSdL1XbxMZjKjKsZ/E1cnBmHqs kdsGjLyYpuHJAOn24719HuQjAZySkkjmo2AhySVDRcDSEoo/NabFbZBwkW8D9Xj4jSZsKzIBPDO zabj2Co6e4REvfSq4sspyI52rBunnC1NasJFIcjqs+w66gwv5XqwkC/KdmliVUvWWKR12OQB23t +gTwx63y5AfOoOMmsr X-Gm-Gg: AR+sD11S8yBE2yVnNc3H3ThP36W2lhkBdLJ52UBjS+yWXIthhCsxu2DGlphR0ydo9Zg 6A6ibGcOcFLDTz1vpkE19lr6OOxYJ3p7NUUWh24hTgvQ647iY0kiV1kSoJtH8/gV0+L598a7RTN LYb/lx+rnUlilCaLvuo/GgunREPBDLDCNdwsQDY4tmLaIwKV7iqcTfOejtlYa49oSaLMUYrIFek FI0i7vjmIvHhtd9HBXY+dsirR6bX3PFPUrqsjO0jtMANkgySVjndmaeWRJbj94FgndroA8a+gYK GemGbtyKtJIlNS3cMcwNc5aJkEZgS88mUVsH0sOIZkFkHfhoimUiFp7fSYlXIb6DFvEldQUaCT+ ZtdYLU16D+NbMYJcXNwuUM7wY3PnxyXwU+iJeyzlklq4jpA== X-Received: by 2002:a05:690c:ec5:b0:80d:6405:d23c with SMTP id 00721157ae682-849f0330f9fmr98024177b3.1.1787585639652; Mon, 24 Aug 2026 08:33:59 -0700 (PDT) X-Received: by 2002:a05:690c:ec5:b0:80d:6405:d23c with SMTP id 00721157ae682-849f0330f9fmr98023737b3.1.1787585639144; Mon, 24 Aug 2026 08:33:59 -0700 (PDT) Received: from bjamison-ThinkPad-P14s-Gen-6-AMD.home.local ([2001:67c:1562:8007::aac:48f9]) by smtp.gmail.com with ESMTPSA id 00721157ae682-84ca5189169sm36343957b3.9.2026.08.24.08.33.57 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 24 Aug 2026 08:33:57 -0700 (PDT) To: kernel-team@lists.ubuntu.com Subject: [SRU][R][PATCH 1/1] drm/i915/dmc: fix assert_dmc_loaded WARN during async firmware load Date: Mon, 24 Aug 2026 10:33:51 -0500 Message-ID: <20260824153354.49939-2-bethany.jamison@canonical.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260824153354.49939-1-bethany.jamison@canonical.com> References: <20260824153354.49939-1-bethany.jamison@canonical.com> MIME-Version: 1.0 X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.20 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Bethany Jamison via kernel-team From: Bethany Jamison Reply-To: Bethany Jamison Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: "kernel-team" From: James Xiong BugLink: https://bugs.launchpad.net/bugs/2156316 During driver probe, DMC firmware is loaded asynchronously via a workqueue. There is a race between parse_dmc_fw() setting the payload pointer (making has_dmc_id_fw() return true) and intel_dmc_load_program() writing the firmware to hardware registers. If the probe thread calls intel_dmc_enable_pipe() -> assert_dmc_loaded() in this window via intel_modeset_setup_hw_state(), it sees parsed payload but stale HW registers, triggering a ~20% intermittent WARNING on ADL-N warm boot. v2: Fix by calling intel_dmc_wait_fw_load() in intel_modeset_setup_hw_state() before iterating the CRTCs (Gustavo Sousa). v3: Move intel_dmc_wait_fw_load() into intel_dmc_enable_pipe() itself so the function is self-contained (Jani Nikula, Gustavo Sousa). Signed-off-by: James Xiong Signed-off-by: Bethany Jamison --- drivers/gpu/drm/i915/display/intel_dmc.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/display/intel_dmc.c b/drivers/gpu/drm/i915/display/intel_dmc.c index 0b15cb764b1d..43e9a3e9f63d 100644 --- a/drivers/gpu/drm/i915/display/intel_dmc.c +++ b/drivers/gpu/drm/i915/display/intel_dmc.c @@ -783,7 +783,12 @@ void intel_dmc_enable_pipe(const struct intel_crtc_state *crtc_state) enum pipe pipe = crtc->pipe; enum intel_dmc_id dmc_id = PIPE_TO_DMC_ID(pipe); - if (!is_valid_dmc_id(dmc_id) || !has_dmc_id_fw(display, dmc_id)) + if (!is_valid_dmc_id(dmc_id)) + return; + + intel_dmc_wait_fw_load(display); + + if (!has_dmc_id_fw(display, dmc_id)) return; if (!can_enable_pipedmc(crtc_state)) {