From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A4D6544CAF5; Tue, 16 Jun 2026 16:54:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781628886; cv=none; b=enn+eKFurN3W64+2grGf3xqQDRqL2vD0r5rD2QL9M21u15HVC2wnrrDpgYvTVE60P1Adf9tG0UFaM26cCkN2pUfnX5anF2lIjz24X1lsu8Im++ewuNLZE2w7pi6TZgFQGlSxw/nRftBY2f0l742uu9C7Nnp3gNpLp6qmberqdv8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781628886; c=relaxed/simple; bh=msDjPLtyyQi3vbjV/z282oEwxkyzvUKX/2Yr17nm7SM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=qdGgaFzBF15UI6Tr+G16rYsQpToqd3vuQeaLsCRj6bXU8hdVr6u1LKnEo/H0M8jSiXc2hFpdRX3m4SooHlaeAozSiKGXSV95m5erPYSy4JOFVUdvmVFn6boc/bEXw/1z1PK36JxY41LkSDGzzR8xAQR0oOQFEFlSNs/BBwFDEHk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=NVTDh6FX; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="NVTDh6FX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6C7991F00A3D; Tue, 16 Jun 2026 16:54:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1781628885; bh=rw4hYbe4ipEVYlKQurrjXQjPkcMvM1j8v0ysgV0w6hM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=NVTDh6FXY8860IMFdA7WUYX1JWgZHe9IedodgWSiDzoSUoc4GME+6CXjPG0UPBGU+ Zo4cbhMjC5GUcaa3WpV0jxiVd3x2Rj4fDSA2Zd1vJlyTtDlBQe4v3w4FiimLlP2pep 7bSysZyI/moUcmQpDWn6AIlDfU86K82jKYPCPElc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Alex Deucher , Jeremy Klarenbeek , =?UTF-8?q?Timur=20Krist=C3=B3f?= Subject: [PATCH 6.6 179/452] drm/amd/pm/si: Disregard vblank time when no displays are connected Date: Tue, 16 Jun 2026 20:26:46 +0530 Message-ID: <20260616145127.266629262@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260616145117.796205997@linuxfoundation.org> References: <20260616145117.796205997@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Timur Kristóf commit dd4f3ee535b3b0ac027f75dbf9dc5fc88733c765 upstream. When no displays are connected, there is no vblank happening so the power management code shouldn't worry about it. This fixes a regression that caused the memory clock to be stuck at maximum when there were no displays connected to a SI GPU. Fixes: 9003a0746864 ("drm/amd/pm: Treat zero vblank time as too short in si_dpm (v3)") Fixes: 9d73b107a61b ("drm/amd/pm: Use pm_display_cfg in legacy DPM (v2)") Reviewed-by: Alex Deucher Tested-by: Jeremy Klarenbeek Signed-off-by: Timur Kristóf Signed-off-by: Alex Deucher (cherry picked from commit 6d87e0199f7b83735b56e422d59f170a201897a8) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/amd/pm/legacy-dpm/si_dpm.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/drivers/gpu/drm/amd/pm/legacy-dpm/si_dpm.c +++ b/drivers/gpu/drm/amd/pm/legacy-dpm/si_dpm.c @@ -3062,6 +3062,10 @@ static bool si_dpm_vblank_too_short(void /* we never hit the non-gddr5 limit so disable it */ u32 switch_limit = adev->gmc.vram_type == AMDGPU_VRAM_TYPE_GDDR5 ? 450 : 0; + /* Disregard vblank time when there are no displays connected */ + if (!adev->pm.pm_display_cfg.num_display) + return false; + /* Consider zero vblank time too short and disable MCLK switching. * Note that the vblank time is set to maximum when no displays are attached, * so we'll still enable MCLK switching in that case.