From patchwork Wed Jul 27 04:50:31 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?UmV4LUJDIENoZW4gKOmZs+afj+i+sCk=?= X-Patchwork-Id: 12930068 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 39624C19F21 for ; Wed, 27 Jul 2022 05:02:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=UPlYmhE1oyETStTigHw+zgok2AMWNkIXUbvs8jcv7pk=; b=P9ydzrMdB4Mj8P pmHSCO5wyqV/of+gyuEUU6lvN1OkT7sTr1lwyRfgkkCROC/Bya+ICkXgXSluqvDxsui8eAc/mKgz9 /c2uY0omJ750wMD9Klm6OhMnv2x6uizySgwCIj8dz861wDyiZ0O6hWbDTTdZkNsUaKe4OiEj04nqe HxE3TEtpIiG1OFrhbDjN1H3sXknWIpW5ze4P3JECCMpijAU7l0jjX7W3IyXkNXaluLMerLEwAFMbu zcvmwnMGQuBjKelLQa/aArkztuKiVZDwiL5hu2LkuRGr3EYg2EBDmpa6pne1MfINQfwPHppH5Hv+Y DO7+CVUwg+sIDCIi/Z0A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oGZBE-009BWQ-7f; Wed, 27 Jul 2022 05:01:56 +0000 Received: from mailgw01.mediatek.com ([216.200.240.184]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oGZB9-009BQl-QR; Wed, 27 Jul 2022 05:01:53 +0000 X-UUID: 6e56c2907d7841a497311132fc788317-20220726 X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.8,REQID:cb7fb628-da6c-4da7-a57e-4a73ea4a2965,OB:0,LO B:0,IP:0,URL:0,TC:0,Content:-5,EDM:0,RT:0,SF:0,FILE:0,RULE:Release_Ham,ACT ION:release,TS:-5 X-CID-META: VersionHash:0f94e32,CLOUDID:6a65eacb-7c9b-4dbc-a9d4-00659d6b7a90,C OID:IGNORED,Recheck:0,SF:nil,TC:nil,Content:0,EDM:-3,IP:nil,URL:0,File:nil ,QS:nil,BEC:nil,COL:0 X-UUID: 6e56c2907d7841a497311132fc788317-20220726 Received: from mtkmbs11n1.mediatek.inc [(172.21.101.185)] by mailgw01.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 958415193; Tue, 26 Jul 2022 22:01:41 -0700 Received: from mtkmbs11n2.mediatek.inc (172.21.101.187) by mtkmbs11n2.mediatek.inc (172.21.101.187) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.792.15; Wed, 27 Jul 2022 12:50:39 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkmbs11n2.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.792.15 via Frontend Transport; Wed, 27 Jul 2022 12:50:39 +0800 From: Bo-Chen Chen To: , , , , , , , , , CC: , , , , , , , , , , , , , , Bo-Chen Chen Subject: [PATCH v15 07/11] drm/mediatek: Add retry to prevent misjudgment for sink devices Date: Wed, 27 Jul 2022 12:50:31 +0800 Message-ID: <20220727045035.32225-8-rex-bc.chen@mediatek.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20220727045035.32225-1-rex-bc.chen@mediatek.com> References: <20220727045035.32225-1-rex-bc.chen@mediatek.com> MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220726_220151_871997_20A7562A X-CRM114-Status: GOOD ( 15.85 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org For some DP dungles, we need to train more than onece to confirm that we don't misjudge the status of sink device. Signed-off-by: Bo-Chen Chen Reviewed-by: AngeloGioacchino Del Regno --- drivers/gpu/drm/mediatek/mtk_dp.c | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/mediatek/mtk_dp.c b/drivers/gpu/drm/mediatek/mtk_dp.c index ce817cb59445..80d7d6488105 100644 --- a/drivers/gpu/drm/mediatek/mtk_dp.c +++ b/drivers/gpu/drm/mediatek/mtk_dp.c @@ -42,6 +42,7 @@ #define MTK_DP_CHECK_SINK_CAP_TIMEOUT_COUNT 3 #define MTK_DP_TBC_BUF_READ_START_ADDR 0x08 #define MTK_DP_TRAIN_DOWNSCALE_RETRY 8 +#define MTK_DP_TRAIN_CLEAR_RETRY 50 struct mtk_dp_train_info { bool tps3; @@ -1431,11 +1432,25 @@ static int mtk_dp_video_config(struct mtk_dp *mtk_dp) static int mtk_dp_training(struct mtk_dp *mtk_dp) { + short max_retry = MTK_DP_TRAIN_CLEAR_RETRY; int ret; - ret = mtk_dp_train_start(mtk_dp); - if (ret) - return ret; + /* + * We do retry to confirm that we don't misjudge the sink status. + * If it is still failed, we can confirm there are some issues for the + * sink device. + */ + do { + ret = mtk_dp_train_start(mtk_dp); + if (!ret) + break; + } while (--max_retry); + + dev_info(mtk_dp->dev, "dp training clear retry times: %d\n", + MTK_DP_TRAIN_CLEAR_RETRY - max_retry); + + if (!max_retry) + return -ETIMEDOUT; ret = mtk_dp_video_config(mtk_dp); if (ret)