From mboxrd@z Thu Jan 1 00:00:00 1970 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 AE777C87FCE for ; Wed, 23 Jul 2025 10:22:40 +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:Cc:To:In-Reply-To:References:Message-Id :MIME-Version:Subject:Date:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=ac3oTt2egjYnntWEqaMUdglqHXI6ZRkVks2i8sOEDn0=; b=zVBiTj81gt1cPm DhYt0z1UaRaFVaxqS4r52vh8R3RANp3PnLoxQWYm9VC0Z5c2xo1WXZiTSZdFxCC5CkIJ0eVPNYIRH 8AirDnRrLExtWggjTLtjGzq22ZvdBRd1X6BxsGbSWS84LaDJEelYi0lHBrqP21i7h6fF6BaQKy55U gmWDws1+AofI3Ppbv5rgOGj6HEv55niyiEkd0xcTVWJBIardbVFvv3haktox0xD+rR8RksYJt1g0t ikxql5eCY/irekgBtvk0PrhGzB+7PPXGfrniON6bMipe8Kv9pSFOrVXEp6Rot9d8MqaDaD7VXtZLc 0VCs2JiGDFDpQyVvU39g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1ueWcS-00000004fZb-1uCW; Wed, 23 Jul 2025 10:22:40 +0000 Received: from perceval.ideasonboard.com ([213.167.242.64]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1ueWM5-00000004cJj-1I9K for linux-phy@lists.infradead.org; Wed, 23 Jul 2025 10:05:46 +0000 Received: from [127.0.1.1] (91-158-153-178.elisa-laajakaista.fi [91.158.153.178]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 0B9DC1129; Wed, 23 Jul 2025 12:05:05 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1753265106; bh=+PxAbR0AgAh+6ttH91klZ+Aji+1hZOcFtaS/g/i1Q0s=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=RX1xMwKKPpK5WRz44L6QlrkdK2tshCe6rta1BfyesxjjiAK0rd9qw1n2zx9AchHFD LHhbk6hlcYg7cvduzEblm0OUQbdlCr0AihRY2/Ht95rNkjLRONyW8AU0hkuLE8KWj8 0D5Wk6GAGxQ4QZQ2cDeGVfnEfdAIRN8jIMLqsmPo= From: Tomi Valkeinen Date: Wed, 23 Jul 2025 13:05:12 +0300 Subject: [PATCH v5 06/15] drm/bridge: cdns-dsi: Remove broken fifo emptying check MIME-Version: 1.0 Message-Id: <20250723-cdns-dsi-impro-v5-6-e61cc06074c2@ideasonboard.com> References: <20250723-cdns-dsi-impro-v5-0-e61cc06074c2@ideasonboard.com> In-Reply-To: <20250723-cdns-dsi-impro-v5-0-e61cc06074c2@ideasonboard.com> To: Jyri Sarha , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Vinod Koul , Kishon Vijay Abraham I , Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Jayesh Choudhary , Dmitry Baryshkov Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-phy@lists.infradead.org, Francesco Dolcini , Aradhya Bhatia , Devarsh Thakkar , Parth Pancholi , Tomi Valkeinen X-Mailer: b4 0.15-dev-c25d1 X-Developer-Signature: v=1; a=openpgp-sha256; l=2010; i=tomi.valkeinen@ideasonboard.com; h=from:subject:message-id; bh=+PxAbR0AgAh+6ttH91klZ+Aji+1hZOcFtaS/g/i1Q0s=; b=owEBbQKS/ZANAwAIAfo9qoy8lh71AcsmYgBogLPrTWKpTI7qlDcFlmzpTrNDGKKo18w9aaIO6 KxFKD5lOS2JAjMEAAEIAB0WIQTEOAw+ll79gQef86f6PaqMvJYe9QUCaICz6wAKCRD6PaqMvJYe 9RRAEACdS40ggRn6TNhjMQt8B5FDvfYJ1X91p5qVBMm853Zy5ZJ1LS1L1M5deJpBeBU2XjGHmvg LGNeNqz/gVeVlGh9Ab8GClyFgcziAl3nWfBRdGXG70Um/OWZjdn8bJRFodJJIGxkjmmWWwwKbtL tTFlVefMDKvHDwCvgVAHG1Rxdtp8bn1L1irWH2x9SmQbmHbLnLkEyL638VGcT+1Aj2jjboVDqE9 ETLyfK5Pe6gRACRz0y7HWsCPIsMDSRxRCZmkDgiBjmCXktMVxul1Dad+V5CmPKZZ4tP4HowXBRV DbZmE1/OrGc4TagxxfrSEPoGh2EFdOMZTaut7xebklIf77rDmJoVSd6l14vLPimsrCy/4QuntH+ iurDqd5h4jAYLJxaW45Bfj2OZvgXGz3vZkbTRxKA+5j0nPnTLGL6XkTnWD/JraXau+K2hcTpkie qoohrmuXfF81+pPSnekpHeL5AmwGIntKlZaqdiphdTFwC26MAxG+NJm94vNOjEbNhJ4rwXUDZqU p2DOiocvo2yADK8cHXVYm0g5zIX5PdnkK3lSbcgr2Lvz5JgQ3xsZZxmlclCg5RRaWpxTVQA/Pwm LF5pYJ7NUvy/ZhLLKhqp/d5M9fXRonuX84oBWrZ77TD6b5rGa9Icr57aKutAqZwsFbwTvZQ47D7 eA5Izv94iKfXodw== X-Developer-Key: i=tomi.valkeinen@ideasonboard.com; a=openpgp; fpr=C4380C3E965EFD81079FF3A7FA3DAA8CBC961EF5 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250723_030545_488776_033A5DE3 X-CRM114-Status: GOOD ( 13.12 ) 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: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-phy" Errors-To: linux-phy-bounces+linux-phy=archiver.kernel.org@lists.infradead.org The driver checks if "DPI(HFP) > DSI(HSS+HSA+HSE+HBP)", and rejects the mode if not. However, testing shows that this doesn't hold at all. I can set the hfp to very small values, with no errors. The feedback from the HW team also was that the check is not right, although it's not clear if there's a way to validate the FIFO emptying. The check rejects quite a lot of modes, apparently for no good reason, so drop the check. Tested-by: Parth Pancholi Tested-by: Jayesh Choudhary Reviewed-by: Devarsh Thakkar Signed-off-by: Tomi Valkeinen --- drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c | 15 --------------- 1 file changed, 15 deletions(-) diff --git a/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c b/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c index eae9469ef431..000c5a2367fe 100644 --- a/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c +++ b/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c @@ -553,7 +553,6 @@ static int cdns_dsi_check_conf(struct cdns_dsi *dsi, { struct cdns_dsi_output *output = &dsi->output; struct phy_configure_opts_mipi_dphy *phy_cfg = &output->phy_opts.mipi_dphy; - unsigned long dsi_hss_hsa_hse_hbp; unsigned int nlanes = output->dev->lanes; int ret; @@ -575,20 +574,6 @@ static int cdns_dsi_check_conf(struct cdns_dsi *dsi, if (ret) return ret; - dsi_hss_hsa_hse_hbp = dsi_cfg->hbp + DSI_HBP_FRAME_OVERHEAD; - if (output->dev->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) - dsi_hss_hsa_hse_hbp += dsi_cfg->hsa + DSI_HSA_FRAME_OVERHEAD; - - /* - * Make sure DPI(HFP) > DSI(HSS+HSA+HSE+HBP) to guarantee that the FIFO - * is empty before we start a receiving a new line on the DPI - * interface. - */ - if ((u64)phy_cfg->hs_clk_rate * - (mode->hsync_start - mode->hdisplay) * nlanes < - (u64)dsi_hss_hsa_hse_hbp * mode->clock * 1000) - return -EINVAL; - return 0; } -- 2.43.0 -- linux-phy mailing list linux-phy@lists.infradead.org https://lists.infradead.org/mailman/listinfo/linux-phy