From patchwork Fri Oct 6 15:07:07 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Tretter X-Patchwork-Id: 13411668 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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 3D407E81E06 for ; Fri, 6 Oct 2023 15:07:30 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 62ACB10E51B; Fri, 6 Oct 2023 15:07:27 +0000 (UTC) Received: from metis.whiteo.stw.pengutronix.de (metis.whiteo.stw.pengutronix.de [IPv6:2a0a:edc0:2:b01:1d::104]) by gabe.freedesktop.org (Postfix) with ESMTPS id CB8B810E518 for ; Fri, 6 Oct 2023 15:07:21 +0000 (UTC) Received: from dude05.red.stw.pengutronix.de ([2a0a:edc0:0:1101:1d::54]) by metis.whiteo.stw.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1qomPy-00051v-D3; Fri, 06 Oct 2023 17:07:06 +0200 From: Michael Tretter Date: Fri, 06 Oct 2023 17:07:07 +0200 Subject: [PATCH v2 5/5] drm/bridge: samsung-dsim: calculate porches in Hz MIME-Version: 1.0 Message-Id: <20230818-samsung-dsim-v2-5-846603df0e0a@pengutronix.de> References: <20230818-samsung-dsim-v2-0-846603df0e0a@pengutronix.de> In-Reply-To: <20230818-samsung-dsim-v2-0-846603df0e0a@pengutronix.de> To: Inki Dae , Jagan Teki , Marek Szyprowski , Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , David Airlie , Daniel Vetter X-Mailer: b4 0.12.0 X-SA-Exim-Connect-IP: 2a0a:edc0:0:1101:1d::54 X-SA-Exim-Mail-From: m.tretter@pengutronix.de X-SA-Exim-Scanned: No (on metis.whiteo.stw.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: dri-devel@lists.freedesktop.org X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Marco Felsch , linux-kernel@vger.kernel.org, Frieder Schrempf , Michael Tretter , dri-devel@lists.freedesktop.org, kernel@pengutronix.de, Adam Ford Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Calculating the byte_clk in kHz is imprecise for a hs_clock of 55687500 Hz, which may be used with a pixel clock of 74.25 MHz with mode 1920x1080-30. Fix the calculation by using HZ instead of kHZ. This requires to change the type to u64 to prevent overflows of the integer type. Reviewed-by: Adam Ford #imx8mm-beacon Tested-by: Adam Ford #imx8mm-beacon Tested-by: Frieder Schrempf # Kontron BL i.MX8MM + Waveshare 10.1inch HDMI LCD (E) Reviewed-by: Marco Felsch Signed-off-by: Michael Tretter --- Changes in v2: None --- drivers/gpu/drm/bridge/samsung-dsim.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/bridge/samsung-dsim.c b/drivers/gpu/drm/bridge/samsung-dsim.c index 714e1e833606..63a0d8dbe37c 100644 --- a/drivers/gpu/drm/bridge/samsung-dsim.c +++ b/drivers/gpu/drm/bridge/samsung-dsim.c @@ -986,10 +986,12 @@ static void samsung_dsim_set_display_mode(struct samsung_dsim *dsi) u32 reg; if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO) { - int byte_clk_khz = dsi->hs_clock / 1000 / 8; - int hfp = DIV_ROUND_UP((m->hsync_start - m->hdisplay) * byte_clk_khz, m->clock); - int hbp = DIV_ROUND_UP((m->htotal - m->hsync_end) * byte_clk_khz, m->clock); - int hsa = DIV_ROUND_UP((m->hsync_end - m->hsync_start) * byte_clk_khz, m->clock); + u64 byte_clk = dsi->hs_clock / 8; + u64 pix_clk = m->clock * 1000; + + int hfp = DIV64_U64_ROUND_UP((m->hsync_start - m->hdisplay) * byte_clk, pix_clk); + int hbp = DIV64_U64_ROUND_UP((m->htotal - m->hsync_end) * byte_clk, pix_clk); + int hsa = DIV64_U64_ROUND_UP((m->hsync_end - m->hsync_start) * byte_clk, pix_clk); /* remove packet overhead when possible */ hfp = max(hfp - 6, 0);