From patchwork Thu Nov 26 21:03:14 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Shankar, Uma" X-Patchwork-Id: 11934699 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7B86BC63777 for ; Thu, 26 Nov 2020 20:30:17 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 3B7E721D7F for ; Thu, 26 Nov 2020 20:30:17 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3B7E721D7F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id CBDAF6EAC8; Thu, 26 Nov 2020 20:30:16 +0000 (UTC) Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by gabe.freedesktop.org (Postfix) with ESMTPS id 9211C6EAC1 for ; Thu, 26 Nov 2020 20:30:08 +0000 (UTC) IronPort-SDR: kVbSy4uWMiSwIYDW6QoXhafd+3Wpdnze0OhyckqixvBjE1s0gsFIMHqVuhsTHxKEeyki6E7R4u y2sdT06xEhHQ== X-IronPort-AV: E=McAfee;i="6000,8403,9817"; a="171543176" X-IronPort-AV: E=Sophos;i="5.78,373,1599548400"; d="scan'208";a="171543176" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Nov 2020 12:30:08 -0800 IronPort-SDR: r85gmoUWWdVq/uF8unDYmVAfQ6UnJL29sJ0P2LUHNq8Dts323R5ovJ4HYOMFBDK5a2QtmOv08u lFvHxA6muODA== X-IronPort-AV: E=Sophos;i="5.78,373,1599548400"; d="scan'208";a="479459634" Received: from linux-desktop.iind.intel.com ([10.223.34.173]) by orsmga004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Nov 2020 12:30:06 -0800 From: Uma Shankar To: intel-gfx@lists.freedesktop.org Date: Fri, 27 Nov 2020 02:33:14 +0530 Message-Id: <20201126210314.7882-16-uma.shankar@intel.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201126210314.7882-1-uma.shankar@intel.com> References: <20201126210314.7882-1-uma.shankar@intel.com> MIME-Version: 1.0 Subject: [Intel-gfx] [v12 15/15] drm/i915/display: [NOT FOR MERGE] Reduce blanking to support 4k60@10bpp for LSPCON X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Blanking needs to be reduced to incorporate DP and HDMI timing/link bandwidth limitations for CEA modes (4k@60 at 10 bpp). DP can drive 17.28Gbs while 4k modes (VIC97 etc) at 10 bpp required 17.8 Gbps. This will cause mode to blank out. Reduced Htotal by shortening the back porch and front porch within permissible limits. Note: This is for reference for userspace, not to be merged in kernel. v2: This is marked as Not for merge and the responsibilty to program these custom timings will be on userspace. This patch is just for reference purposes. This is based on Ville's recommendation. v3: updated commit message. Signed-off-by: Uma Shankar --- drivers/gpu/drm/i915/display/intel_dp.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c index 0f89dbfa958a..f6f66033176b 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.c +++ b/drivers/gpu/drm/i915/display/intel_dp.c @@ -741,8 +741,10 @@ intel_dp_mode_valid(struct drm_connector *connector, { struct intel_dp *intel_dp = intel_attached_dp(to_intel_connector(connector)); struct intel_connector *intel_connector = to_intel_connector(connector); + struct intel_encoder *intel_encoder = intel_attached_encoder(intel_connector); struct drm_display_mode *fixed_mode = intel_connector->panel.fixed_mode; struct drm_i915_private *dev_priv = to_i915(connector->dev); + struct intel_lspcon *lspcon = enc_to_intel_lspcon(intel_encoder); int target_clock = mode->clock; int max_rate, mode_rate, max_lanes, max_link_clock; int max_dotclk = dev_priv->max_dotclk_freq; @@ -778,6 +780,21 @@ intel_dp_mode_valid(struct drm_connector *connector, if (target_clock > max_dotclk) return MODE_CLOCK_HIGH; + /* + * Reducing Blanking to incorporate DP and HDMI timing/link bandwidth + * limitations for CEA modes (4k@60 at 10 bpp). DP can drive 17.28Gbs + * while 4k modes (VIC97 etc) at 10 bpp required 17.8 Gbps. This will + * cause mode to blank out. Reduced Htotal by shortening the back porch + * and front porch within permissible limits. + */ + if (lspcon->active && lspcon->hdr_supported && + mode->clock > 570000) { + mode->clock = 570000; + mode->htotal -= 180; + mode->hsync_start -= 72; + mode->hsync_end -= 72; + } + max_link_clock = intel_dp_max_link_rate(intel_dp); max_lanes = intel_dp_max_lane_count(intel_dp);