From patchwork Mon Jul 17 06:18:27 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Liu Ying X-Patchwork-Id: 13316391 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 mail-vi1eur05on20614.outbound.protection.outlook.com ([2a01:111:f400:7d00::614] helo=EUR05-VI1-obe.outbound.protection.outlook.com) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qLHUz-002zno-0Y for linux-arm-kernel@lists.infradead.org; Mon, 17 Jul 2023 06:14:23 +0000 From: Liu Ying Subject: [PATCH 5/9] drm/bridge: synopsys: dw-mipi-dsi: Use pixel clock rate to calculate lbcc Date: Mon, 17 Jul 2023 14:18:27 +0800 Message-Id: <20230717061831.1826878-6-victor.liu@nxp.com> In-Reply-To: <20230717061831.1826878-1-victor.liu@nxp.com> References: <20230717061831.1826878-1-victor.liu@nxp.com> MIME-Version: 1.0 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+lwn-linux-arm-kernel=archive.lwn.net@lists.infradead.org List-Archive: To: dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: andrzej.hajda@intel.com, neil.armstrong@linaro.org, rfoss@kernel.org, Laurent.pinchart@ideasonboard.com, jonas@kwiboo.se, jernej.skrabec@gmail.com, airlied@gmail.com, daniel@ffwll.ch, robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org, shawnguo@kernel.org, s.hauer@pengutronix.de, kernel@pengutronix.de, festevam@gmail.com, linux-imx@nxp.com To get better accuration, use pixel clock rate to calculate lbcc instead of lane_mbps since the pixel clock rate is in KHz while lane_mbps is in MHz. Without this, distorted image can be seen on a HDMI monitor connected with i.MX93 11x11 EVK through ADV7535 DSI to HDMI bridge in 1920x1080p@60 video mode. Signed-off-by: Liu Ying Reviewed-by: Neil Armstrong --- drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c index c754d55f71d1..332388fd86da 100644 --- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c +++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c @@ -12,6 +12,7 @@ #include #include #include +#include #include #include #include @@ -762,8 +763,15 @@ static u32 dw_mipi_dsi_get_hcomponent_lbcc(struct dw_mipi_dsi *dsi, u32 hcomponent) { u32 frac, lbcc; + int bpp; - lbcc = hcomponent * dsi->lane_mbps * MSEC_PER_SEC / 8; + bpp = mipi_dsi_pixel_format_to_bpp(dsi->format); + if (bpp < 0) { + dev_err(dsi->dev, "failed to get bpp\n"); + return 0; + } + + lbcc = div_u64((u64)hcomponent * mode->clock * bpp, dsi->lanes * 8); frac = lbcc % mode->clock; lbcc = lbcc / mode->clock;