From patchwork Thu Sep 28 11:36:24 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lucas Stach X-Patchwork-Id: 13402843 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 46091E732C7 for ; Thu, 28 Sep 2023 11:36:42 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A8B0910E626; Thu, 28 Sep 2023 11:36:36 +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 A326B10E623 for ; Thu, 28 Sep 2023 11:36:32 +0000 (UTC) Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1qlpJm-0001s0-1z; Thu, 28 Sep 2023 13:36:30 +0200 Received: from [2a0a:edc0:0:1101:1d::28] (helo=dude02.red.stw.pengutronix.de) by drehscheibe.grey.stw.pengutronix.de with esmtp (Exim 4.94.2) (envelope-from ) id 1qlpJl-009Z8S-KS; Thu, 28 Sep 2023 13:36:29 +0200 From: Lucas Stach To: Marek Vasut , Liu Ying Subject: [PATCH v3 3/8] drm: lcdif: enable DMA before display Date: Thu, 28 Sep 2023 13:36:24 +0200 Message-Id: <20230928113629.103188-3-l.stach@pengutronix.de> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230928113629.103188-1-l.stach@pengutronix.de> References: <20230928113629.103188-1-l.stach@pengutronix.de> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2a0a:edc0:0:c01:1d::a2 X-SA-Exim-Mail-From: l.stach@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: linux-arm-kernel@lists.infradead.org, dri-devel@lists.freedesktop.org, NXP Linux Team , Pengutronix Kernel Team , patchwork-lst@pengutronix.de Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Otherwise the DMA enable races with the fetch start, which causes wrong or no data to be scanned out on the first frame. Also there is no point in waiting for the DMA disable when the controller is going to shut down. Simply disable the display first so no further fetches are triggered and then shut down DMA. Signed-off-by: Lucas Stach --- v3: new patch --- drivers/gpu/drm/mxsfb/lcdif_kms.c | 23 ++++++++--------------- 1 file changed, 8 insertions(+), 15 deletions(-) diff --git a/drivers/gpu/drm/mxsfb/lcdif_kms.c b/drivers/gpu/drm/mxsfb/lcdif_kms.c index e277592e5fa5..6a292f4b332b 100644 --- a/drivers/gpu/drm/mxsfb/lcdif_kms.c +++ b/drivers/gpu/drm/mxsfb/lcdif_kms.c @@ -358,34 +358,27 @@ static void lcdif_enable_controller(struct lcdif_drm_private *lcdif) writel(INT_ENABLE_D1_PLANE_PANIC_EN, lcdif->base + LCDC_V8_INT_ENABLE_D1); - reg = readl(lcdif->base + LCDC_V8_DISP_PARA); - reg |= DISP_PARA_DISP_ON; - writel(reg, lcdif->base + LCDC_V8_DISP_PARA); - reg = readl(lcdif->base + LCDC_V8_CTRLDESCL0_5); reg |= CTRLDESCL0_5_EN; writel(reg, lcdif->base + LCDC_V8_CTRLDESCL0_5); + + reg = readl(lcdif->base + LCDC_V8_DISP_PARA); + reg |= DISP_PARA_DISP_ON; + writel(reg, lcdif->base + LCDC_V8_DISP_PARA); } static void lcdif_disable_controller(struct lcdif_drm_private *lcdif) { u32 reg; - int ret; - - reg = readl(lcdif->base + LCDC_V8_CTRLDESCL0_5); - reg &= ~CTRLDESCL0_5_EN; - writel(reg, lcdif->base + LCDC_V8_CTRLDESCL0_5); - - ret = readl_poll_timeout(lcdif->base + LCDC_V8_CTRLDESCL0_5, - reg, !(reg & CTRLDESCL0_5_EN), - 0, 36000); /* Wait ~2 frame times max */ - if (ret) - drm_err(lcdif->drm, "Failed to disable controller!\n"); reg = readl(lcdif->base + LCDC_V8_DISP_PARA); reg &= ~DISP_PARA_DISP_ON; writel(reg, lcdif->base + LCDC_V8_DISP_PARA); + reg = readl(lcdif->base + LCDC_V8_CTRLDESCL0_5); + reg &= ~CTRLDESCL0_5_EN; + writel(reg, lcdif->base + LCDC_V8_CTRLDESCL0_5); + /* Disable FIFO Panic NoC priority booster. */ writel(0, lcdif->base + LCDC_V8_INT_ENABLE_D1); }