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 8D44EC71157 for ; Wed, 18 Jun 2025 10:24:31 +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=r90bXvez/7BHnKvw7+9xRvztijYmRWsfpZqai4hAL2M=; b=MxRHmNDIICnjXm YMfCAba9fdBI0b5Zg9l2V5I499z7XeM1s0+AP4wukOrGRJ+S0auLId29/hjTeXLKt4oXD9MDwa7K4 e+Mnw5ux61MUc7y6fpOdCgenleTVwEoQDITBF/2/F+iCpYc1+d8U+aYk7kIzNCMrVmmR5ir2D8wJT v+8jlDM670B+HMtccwc5kuELtMv6oLmD0VR+RVBo8CDt7bIeuxFYtKfE5eME7H3yQ0SRp6Ymx1Whs +PDlvY05SfEitviTq07+v38nC9JnXAsDijG/npniuQJvQ79vxyTKYQtRhZTVTZURHY0IO+CI8BNcl cQ5WGur+Lp4OZv0zoOEg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uRpy3-00000009lz1-1ItA; Wed, 18 Jun 2025 10:24:31 +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 1uRpa3-00000009gRt-2RXh for linux-phy@lists.infradead.org; Wed, 18 Jun 2025 09:59:45 +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 998761C0A; Wed, 18 Jun 2025 11:59:28 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1750240769; bh=J+6mryuTRX2gB2Rgwr5vt3wvRXw/gjqeHL//L5Wxqhg=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=T3iYIrar75xKvopy8iyPp682uIw3x4Y9FogbGQ7mismuvIRBMulfwMqJVHPZey7wE HHB93oOnGr6PgCJO3BzEKv+hbejUqy9sBhW/llHyDHBuVfdani2k7VEO8BVLD6nwlh U5pWGxOFQoZfc5sGY4s90fApu92lDoThyFgMVhUI= From: Tomi Valkeinen Date: Wed, 18 Jun 2025 12:59:11 +0300 Subject: [PATCH v4 08/17] drm/bridge: cdns-dsi: Remove broken fifo emptying check MIME-Version: 1.0 Message-Id: <20250618-cdns-dsi-impro-v4-8-862c841dbe02@ideasonboard.com> References: <20250618-cdns-dsi-impro-v4-0-862c841dbe02@ideasonboard.com> In-Reply-To: <20250618-cdns-dsi-impro-v4-0-862c841dbe02@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=1912; i=tomi.valkeinen@ideasonboard.com; h=from:subject:message-id; bh=J+6mryuTRX2gB2Rgwr5vt3wvRXw/gjqeHL//L5Wxqhg=; b=kA0DAAgB+j2qjLyWHvUByyZiAGhSjf+jRxOSwxnZRMFSceTkzN1h9dgwbT4lCoGBjujnNms6U 4kCMwQAAQgAHRYhBMQ4DD6WXv2BB5/zp/o9qoy8lh71BQJoUo3/AAoJEPo9qoy8lh71lpwQAIfJ VrMy5bauKUmd9xIUo0jiekemLRGhuaztMb+is2MO0QH8ErEsgc0IMiM8XMVtkq5Ca1FqOlwT8KB zkzM/10coueclGz+Z0zx/GW8Y18RBO7gtoysWorMmMt+ifiBAl0juBpPExXr9/UOp6ENDK0pe/Q 2Xp1yoTtxe9p+2KgVO3EC+RFU31r/62bX3YqOL8D+w3BgJ/vv4ajN8jJqBwcXG0JsLfG+nG06zM 6m12aWPYwhdLcN3xEboR6Y+eitY4Us7sBnpjbeJj1+DhgWZsFe37m2kYGKeP65M0a0MuKMZqdYv dPRWbg20uLx1dafO2ovAWvzsDvHijyqlHfX1DxMFKbMqJj4QOgqrXQAHlYsBA4xWFVAxyAFjcVy qzvYtrjs4Dk7xGtLkWTtYBjL7oK67BlLdpiP3UF3fvxIQNLj9i/uy2LHFFfRtDfbVT9CggJSdyR hNbURV9cqIix4TYLxRMhD/AbHpiqUHzKkfg/P5m7ZzwRmmDnohil5BXBi2pWEQfxh6uYKtATlO9 lui7zCmOPxb3nEuAu4jGtcdYrjAicjEDzOU0gyVMRmG2UYzSHe5o+NONbVNwTIBHAjT5MnvlpfF XBSXj0/Jw656GXz3n3llzxTKb9UVJihrZD5vP6vmbOGttmQtN3jGboqSlXzFNM1IEoXTqK/b4IU AH279 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-20250618_025943_772413_FE50B842 X-CRM114-Status: GOOD ( 12.92 ) 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 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