From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailgw02.mediatek.com (unknown [210.61.82.184]) (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 B4F533D561 for ; Tue, 4 Nov 2025 09:00:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=210.61.82.184 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762246811; cv=none; b=Pb1BAudoXa6Nrm3vciYXi7ZfCAdWbfe4iOpphI0q5MhwwKgYeK3i1+OrS+mtsI9qXQuAJ2UJ8pt/7ox8FRLDEQ5n5vQly4MR8d8UabwBAVsboYand6qIyIe7ZruW3tkFR3wEpe3q7+wSy8xTk7wtv6u9dHtDlfaEReqmURIV7D8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762246811; c=relaxed/simple; bh=MafG4x+hS//j+xbm2wp29pa1ORJntMLER3jmSWrbH0k=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=HMYVNOnjWT9RMtm9I2daShFeRo7CgkWU5WngyxCAV2dnXxS0iFJKsGq55Ude0vAXWlr2UXVXm/6KkDPHFaEG1EpI1ZErmqSQ4zxYeCb+ejWaY1MaU7jz5Y8QQGBIahoVrGJnhmXdoXyFAMbfAXu6HAFhjif+N0lUqNm4VrcdwYI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=mediatek.com; spf=pass smtp.mailfrom=mediatek.com; dkim=pass (1024-bit key) header.d=mediatek.com header.i=@mediatek.com header.b=YOUU5Xq0; arc=none smtp.client-ip=210.61.82.184 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=mediatek.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=mediatek.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=mediatek.com header.i=@mediatek.com header.b="YOUU5Xq0" X-UUID: a5e43718b95c11f0b33aeb1e7f16c2b6-20251104 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Type:Content-Transfer-Encoding:MIME-Version:Message-ID:Date:Subject:CC:To:From; bh=5V/Vz/H8HM7LchfMCgMJIzRqE49QYJch3AIZX3W5lns=; b=YOUU5Xq0LuMjGkUosfD+LrR/zgy9bAUAy8mkE6TOqZsjVk1ieVKYuCo1c6YYq0ir8+TbfDqZMHaTLCLiohJJIqYa+o1xwBsgi0p/HM4wYfG4UZBXuU3ciaO+mXqyMtY0cBbNN28QXagzJSJvU7B7ZVJxUb39OHvKFTlT9H07ytI=; X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.3.6,REQID:446a5c81-18e9-4894-afdf-a74b4e83fa2a,IP:0,UR L:0,TC:0,Content:0,EDM:0,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTION:r elease,TS:0 X-CID-META: VersionHash:a9d874c,CLOUDID:726e056b-d4bd-4ab9-8221-0049857cc502,B ulkID:nil,BulkQuantity:0,Recheck:0,SF:102|836|888|898,TC:-5,Content:0|15|5 0,EDM:-3,IP:nil,URL:0,File:130,RT:0,Bulk:nil,QS:nil,BEC:nil,COL:0,OSI:0,OS A:0,AV:0,LES:1,SPR:NO,DKR:0,DKP:0,BRR:0,BRE:0,ARC:0 X-CID-BVR: 2,SSN|SDN X-CID-BAS: 2,SSN|SDN,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR X-CID-RHF: D41D8CD98F00B204E9800998ECF8427E X-UUID: a5e43718b95c11f0b33aeb1e7f16c2b6-20251104 Received: from mtkmbs13n2.mediatek.inc [(172.21.101.108)] by mailgw02.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 1963540864; Tue, 04 Nov 2025 17:00:01 +0800 Received: from mtkmbs13n1.mediatek.inc (172.21.101.193) by mtkmbs13n1.mediatek.inc (172.21.101.193) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1748.26; Tue, 4 Nov 2025 17:00:00 +0800 Received: from mszsdhlt06.gcn.mediatek.inc (10.16.6.206) by mtkmbs13n1.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.1748.26 via Frontend Transport; Tue, 4 Nov 2025 16:59:59 +0800 From: Liankun Yang To: , , , , , , , , , CC: , , , Subject: [PATCH v7 0/2] Adjust bandwidth limit for DP Date: Tue, 4 Nov 2025 16:55:10 +0800 Message-ID: <20251104085957.1175-1-liankun.yang@mediatek.com> X-Mailer: git-send-email 2.45.2 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-MTK: N DP link training checks the current PHY link signal quality. After DP detects an HPD connection, it should first determine the current link signal quality in order to select the resolution. Since the EDP is already fixed to use the EDP panel, the current training information and resolution are basically fixed. EDP exists and its process differs from DP. Therefore, it is necessary to isolate the parsing capability, panel power, training state and enable state. For example, the platform support DP 4lane 5.4G, but panel A support DP 2lane 5.4G. This is a time sequence: 1. Plug in panel A. According to the platform, it can output 4K 60Hz. 2. Timing mode set 4K 60Hz. 3. Atomic enable(Based on panel A ability, training pass 2lane 5.4G). 4. Finally, due to 2lane 5.4G bandwidth limitation, the platform cannot output 4K 60Hz, resulting in a black sreen. If apply this patch. 1. Plug in panel A. 2. Training pass 2lane 5.4G 3. Timing mode set 2K 60Hz(Based on the 2lane 5.4G bandwidth limit). 4. Atomic enable for output screen. Liankun Yang (2): drm/mediatek: Adjust bandwidth limit for DP drm/mediatek: Add isolation to edp drivers/gpu/drm/mediatek/mtk_dp.c | 57 ++++++++++++++++++++----------- 1 file changed, 38 insertions(+), 19 deletions(-) -- 2.45.2