From patchwork Wed Apr 3 04:05:09 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?TElBTktVTiBZQU5HICjmnajov57lnaQp?= X-Patchwork-Id: 13614940 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 170B0CD1288 for ; Wed, 3 Apr 2024 04:20:03 +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: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:In-Reply-To:References: List-Owner; bh=34x76lLfBzY0LsUSYENYmdgj+l/NIPLzT4WnTaVCcnQ=; b=Bqn9g4axP8DA53 3wkCYTpJjMficHSRQ89spxMyHVOZ7f8CV2zJby9sSJDO8iykdo/+Sd8TE4tVbpJjqZNrNkANblkpg /XJPzKN9qfGV5BZpmul/0dkwSE3qIRMSarn0UxajQadlt28JHPjUxbJSG1MXk6VbBpbHthsZSebOo 0DxVWNUVadbl4R7c0uYzQ89rqVUNM17Vz9VBL+ZtXlHImMu7JIGPuZaJJOWGQwxFUGBm2kRLgzQ5d TsqyvbHe0jON1qPkrZVHnS9+0nN+FHqNYTBm7RG7QwdM1fwOu4OTMVavf9reP3LI7r4E9zqKf6HKi HXYVCEYsUIko0hvqmmtw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rrs6U-0000000DvKX-37WZ; Wed, 03 Apr 2024 04:20:02 +0000 Received: from mailgw01.mediatek.com ([216.200.240.184]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rrs6R-0000000DvIk-362I; Wed, 03 Apr 2024 04:20:01 +0000 X-UUID: 44b52eccf16f11eeac1957ae9f99f617-20240402 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=yYxp0aFWjJkoN+/b1M2v5KOdqMIidnWV+rOPGvVUSa4=; b=lpY8OyTgKwCO+kg0P8iyURu/yQg4/QHOuKh9g00tGCf5S18AZcnR+5xAkKo6jN/LbFIie+FwSr3i+TLDDBTL5CmfEMTWtdSquSKo1TtNsyAs6vMmWerK7QUFZcnRcnmTunagnS4dexCYJBVw4++iqprAPhVkOJZYk2FaCUjjdjo=; X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.37,REQID:0eba7961-5631-408a-831e-839b96d315f8,IP:0,U RL:0,TC:0,Content:-5,EDM:0,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTION :release,TS:-5 X-CID-META: VersionHash:6f543d0,CLOUDID:cf9cc185-8d4f-477b-89d2-1e3bdbef96d1,B ulkID:nil,BulkQuantity:0,Recheck:0,SF:102,TC:nil,Content:0,EDM:-3,IP:nil,U RL:0,File:nil,RT:nil,Bulk:nil,QS:nil,BEC:nil,COL:0,OSI:0,OSA:0,AV:0,LES:1, SPR:NO,DKR:0,DKP:0,BRR:0,BRE:0 X-CID-BVR: 0,NGT X-CID-BAS: 0,NGT,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR X-UUID: 44b52eccf16f11eeac1957ae9f99f617-20240402 Received: from mtkmbs13n2.mediatek.inc [(172.21.101.108)] by mailgw01.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 73209606; Tue, 02 Apr 2024 21:04:29 -0700 Received: from mtkmbs13n2.mediatek.inc (172.21.101.108) 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 15.2.1118.26; Wed, 3 Apr 2024 12:04:26 +0800 Received: from mszsdhlt06.gcn.mediatek.inc (10.16.6.206) by mtkmbs13n2.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.1118.26 via Frontend Transport; Wed, 3 Apr 2024 12:04:25 +0800 From: Liankun Yang To: , , , , , , , , , CC: , , , , Subject: [PATCH v1 1/1] drm/mediatek/dp: The register is written with the parsed DTS SSC value. Date: Wed, 3 Apr 2024 12:05:09 +0800 Message-ID: <20240403040517.3279-1-liankun.yang@mediatek.com> X-Mailer: git-send-email 2.43.0 MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240402_211959_798212_BD70C6ED X-CRM114-Status: GOOD ( 18.23 ) X-BeenThere: linux-phy@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Linux Phy Mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-phy" Errors-To: linux-phy-bounces+linux-phy=archiver.kernel.org@lists.infradead.org [Description] Severe screen flickering has been observed on the external display when the DP projection function is used with the market expansion dock. [Root cause] It has been discovered through analysis that severe screen flickering will occur when using the current default settings of SC (Spread Spectrum Clocking) after it is opened. [Solution] Reducing SSC capability on the test platform can resolve the screen flickering issue. By configuring SSC parameters in DTS, locating the DP SSC node in phy-mtk-dp, parsing the current value of SSC, and writing this value into PHY to configure SSC can solve the screen flickering problem. [Test] The SSC configuration values are read from DTS, parsed in the driver, and then written to the hardware. The test results indicate that there is no screen flickering. Signed-off-by: Liankun Yang --- drivers/phy/mediatek/phy-mtk-dp.c | 61 +++++++++++++++++++++++++++++++ 1 file changed, 61 insertions(+) diff --git a/drivers/phy/mediatek/phy-mtk-dp.c b/drivers/phy/mediatek/phy-mtk-dp.c index d7024a144335..13e5d3c33784 100644 --- a/drivers/phy/mediatek/phy-mtk-dp.c +++ b/drivers/phy/mediatek/phy-mtk-dp.c @@ -25,6 +25,10 @@ #define BIT_RATE_HBR2 2 #define BIT_RATE_HBR3 3 +#define MTK_DP_PHY_DIG_GLB_DA_REG_14 (PHY_OFFSET + 0xD8) +#define XTP_GLB_TXPLL_SSC_DELTA_RBR_DEFAULT GENMASK(15, 0) +#define XTP_GLB_TXPLL_SSC_DELTA_HBR_DEFAULT GENMASK(31, 16) + #define MTK_DP_PHY_DIG_SW_RST (PHY_OFFSET + 0x38) #define DP_GLB_SW_RST_PHYD BIT(0) @@ -78,10 +82,57 @@ #define DRIVING_PARAM_8_DEFAULT (XTP_LN_TX_LCTXCP1_SW2_PRE1_DEFAULT | \ XTP_LN_TX_LCTXCP1_SW3_PRE0_DEFAULT) +#define SSC_SETTING "dp-ssc-setting" +#define RG_XTP_GLB_TXPLL_SSC_DELTA_RBR "ssc-delta-rbr" +#define RG_XTP_GLB_TXPLL_SSC_DELTA_HBR "ssc-delta-hbr" + struct mtk_dp_phy { struct regmap *regs; + struct device *dev; }; +static int mtk_dp_set_ssc_config(struct phy *phy, struct mtk_dp_phy *dp_phy, + struct device_node *ssc_node, const char *mode_name, u32 ssc_reg_offset) +{ + int ret; + u32 read_value = 0; + + ret = of_property_read_u32(ssc_node, mode_name, &read_value); + if (ret) { + dev_err(&phy->dev, "Read fail,DPTX is not %s\n", mode_name); + return -EINVAL; + } + + if (!read_value) { + dev_err(&phy->dev, "Read value is NULL\n"); + return -ENOMEM; + } + + if (!strcmp(mode_name, RG_XTP_GLB_TXPLL_SSC_DELTA_RBR)) { + regmap_update_bits(dp_phy->regs, ssc_reg_offset, + XTP_GLB_TXPLL_SSC_DELTA_RBR_DEFAULT, read_value); + } else if (!strcmp(mode_name, RG_XTP_GLB_TXPLL_SSC_DELTA_HBR)) { + read_value = read_value << 16 | 0x0000; + regmap_update_bits(dp_phy->regs, ssc_reg_offset, + XTP_GLB_TXPLL_SSC_DELTA_HBR_DEFAULT, read_value); + } + + return 0; +} + +static struct device_node *mtk_dp_get_ssc_node(struct phy *phy, struct mtk_dp_phy *dp_phy) +{ + struct device_node *mode_node = NULL; + + mode_node = of_find_node_by_name(dp_phy->dev->of_node, SSC_SETTING); + if (!mode_node) { + dev_err(&phy->dev, "SSC node is NULL\n"); + return NULL; + } + + return mode_node; +} + static int mtk_dp_phy_init(struct phy *phy) { struct mtk_dp_phy *dp_phy = phy_get_drvdata(phy); @@ -109,6 +160,7 @@ static int mtk_dp_phy_init(struct phy *phy) static int mtk_dp_phy_configure(struct phy *phy, union phy_configure_opts *opts) { struct mtk_dp_phy *dp_phy = phy_get_drvdata(phy); + struct device_node *ssc_node = NULL; u32 val; if (opts->dp.set_rate) { @@ -137,6 +189,14 @@ static int mtk_dp_phy_configure(struct phy *phy, union phy_configure_opts *opts) regmap_update_bits(dp_phy->regs, MTK_DP_PHY_DIG_PLL_CTL_1, TPLL_SSC_EN, opts->dp.ssc ? TPLL_SSC_EN : 0); + ssc_node = mtk_dp_get_ssc_node(phy, dp_phy); + if (ssc_node) { + mtk_dp_set_ssc_config(phy, dp_phy, ssc_node, RG_XTP_GLB_TXPLL_SSC_DELTA_RBR, + MTK_DP_PHY_DIG_GLB_DA_REG_14); + mtk_dp_set_ssc_config(phy, dp_phy, ssc_node, RG_XTP_GLB_TXPLL_SSC_DELTA_HBR, + MTK_DP_PHY_DIG_GLB_DA_REG_14); + } + return 0; } @@ -186,6 +246,7 @@ static int mtk_dp_phy_probe(struct platform_device *pdev) if (!dev->of_node) phy_create_lookup(phy, "dp", dev_name(dev)); + dp_phy->dev = dev; return 0; }