From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793213583; b=TznUUokNxky3JCOk5LLimFaLPgkZiyDfGqfXVKv4GylutUxmdWmaRt7reNsQS1Ub68su SF12ZnhUnFhkSzfTKb7CBheaXibkWQY2noIcaQOH/7akF6NbWHfeH0CkKK66pu98W5IEU U55iU8yILnPdXw2/xXu6yJJwZYdFcyH3MJxO8ZUk+E7gAxxslCLJ6qNWKHwIYLgpYHKBf bXNdR4Rrsg4j9Sf/i7hZVg8xrsdAIB5UEdqtC1xbuaZjbTOdST5Vkr6aw3ArNsT3Yk3Zl FxlFDUpc15ZK3mMRqSkWBgIEvxhHY8s42h0sjbUHvmuKCOMUnn7Ov12xAzl6hI67xuw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793213583; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=YAh5Q+j3wHYpo8zH0xw6ajaJ6zAnjgfU5z/Bz0EqsMs=; b=MJYMnJufKjtHi/SC9npj1XF0zeXwzqBoN0qvf4m8BEmpaDYQsD0VY/PWzRYKu7PuVJ0q xnFfaPqvm9c8mVb+MlcRyZ5pSbjnviL6Zg1jMziGi2oIWZMnrz5zzl4wkgcQ1FGmy4B0F yHEzDBDJZ82Z/A06Rino4GGSHcoE3wxWCTxprZoccWeXrsFvH0UWZAae1OP4pPbfsj/9a iYFOcBtLPsQhJrDllp253MzURpV0EE67G7gs0fzVshcb7dbdLGXNT8thmwuSpWgIbbD8B 20H3V0AtGXNxh4zY4zZY6JKNZuY87venWH+6haoMUrByFv6jBfuUZY0vzUK1TX+F1RQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=GIK05R9u; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4FD6B606A31F; Wed, 28 Oct 2026 18:53:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=GIK05R9u Received: by smtp.kernel.org (Postfix) with ESMTPSA id A68211F01825; Wed, 28 Oct 2026 18:53:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793213583; bh=YAh5Q+j3wHYpo8zH0xw6ajaJ6zAnjgfU5z/Bz0EqsMs=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=GIK05R9uNicMiRtrpPrHpIG+4+pT25/Q49AbwDP9PeA1G8oxg7U8EYkUmZC1OE11F OS5Kxc2FrsanzcnE6agZhYgGSqGB8jh4YEEJvETY8JUYI1QgMtkLkTlxa+OeYS5D5q vzvgEvlU1MyhXM5L2bIgp6+4NgKDVmvQWY4IPRUU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Alvin Lee , Wayne Lin , Ilya Bakoulin , Daniel Wheeler , Alex Deucher , Sasha Levin Subject: [PATCH 6.1 0557/1887] drm/amd/display: Fix hang/underflow when transitioning to ODM4:1 Date: Wed, 28 Oct 2026 17:44:13 +0100 Message-ID: <20261028170512.055930907@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261028170459.200466217@linuxfoundation.org> References: <20261028170459.200466217@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ilya Bakoulin [ Upstream commit e7b2b108cdeab76a7e7324459e50b0c1214c0386 ] [Why] Under some circumstances, disabling an OPTC and attempting to reclaim its OPP(s) for a different OPTC could cause a hang/underflow due to OPPs not being properly disconnected from the disabled OPTC. [How] Ensure that all OPPs are unassigned from an OPTC when it gets disabled. Reviewed-by: Alvin Lee Acked-by: Wayne Lin Signed-off-by: Ilya Bakoulin Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher Signed-off-by: Sasha Levin --- drivers/gpu/drm/amd/display/dc/dcn314/dcn314_optc.c | 7 +++++++ drivers/gpu/drm/amd/display/dc/dcn32/dcn32_optc.c | 7 +++++++ 2 files changed, 14 insertions(+) diff --git a/drivers/gpu/drm/amd/display/dc/dcn314/dcn314_optc.c b/drivers/gpu/drm/amd/display/dc/dcn314/dcn314_optc.c index 7dd36e402bac7..56487ba4d00e6 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn314/dcn314_optc.c +++ b/drivers/gpu/drm/amd/display/dc/dcn314/dcn314_optc.c @@ -139,6 +139,13 @@ static bool optc314_disable_crtc(struct timing_generator *optc) REG_UPDATE(OTG_CONTROL, OTG_MASTER_EN, 0); + REG_UPDATE_5(OPTC_DATA_SOURCE_SELECT, + OPTC_SEG0_SRC_SEL, 0xf, + OPTC_SEG1_SRC_SEL, 0xf, + OPTC_SEG2_SRC_SEL, 0xf, + OPTC_SEG3_SRC_SEL, 0xf, + OPTC_NUM_OF_INPUT_SEGMENT, 0); + REG_UPDATE(CONTROL, VTG0_ENABLE, 0); diff --git a/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_optc.c b/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_optc.c index 37c645a882dd8..4a2fa9bb5393c 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_optc.c +++ b/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_optc.c @@ -145,6 +145,13 @@ static bool optc32_disable_crtc(struct timing_generator *optc) REG_UPDATE(OTG_CONTROL, OTG_MASTER_EN, 0); + REG_UPDATE_5(OPTC_DATA_SOURCE_SELECT, + OPTC_SEG0_SRC_SEL, 0xf, + OPTC_SEG1_SRC_SEL, 0xf, + OPTC_SEG2_SRC_SEL, 0xf, + OPTC_SEG3_SRC_SEL, 0xf, + OPTC_NUM_OF_INPUT_SEGMENT, 0); + REG_UPDATE(CONTROL, VTG0_ENABLE, 0); -- 2.53.0