From patchwork Thu Mar 2 08:15:32 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arun R Murthy X-Patchwork-Id: 13156790 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 B14EDC6FA8E for ; Thu, 2 Mar 2023 08:21:09 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 4B87B10E3E9; Thu, 2 Mar 2023 08:21:01 +0000 (UTC) Received: from mga18.intel.com (mga18.intel.com [134.134.136.126]) by gabe.freedesktop.org (Postfix) with ESMTPS id 2E9E510E3E3; Thu, 2 Mar 2023 08:20:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1677745258; x=1709281258; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=Tzw/h8feKEG69Dql62f2HqSjZs3B07o57rYeIIF7tp4=; b=MUl5skQW6Fbm5tbC62YugpmM/NC0TSNQxdpB3jYfuInIPxRTZXQVHHOZ nCNEhxx/4lXyErfupJ3PpFtkiK/AR9b027yOhmiw1r3smPS7fbB+KDpfy Gm6KMqQNoRFRv5+UPq1NtZ0YYuFjxxoJM/afVd+n1yay1Tph2MW1oI1eJ LDX96pjO7r/fDsR2tMSZ7o3KnNfLUhPXVEso3tBe8gw3aFnqnUNRjP/0P 2Ztn6/l9Bod653+aqd6VEx2rHCmR3s4fvI7rL5Wz5iX820FoBlStd7rrN hUHifUhHS7YttoTGFx3FGC0jbhziboTkr/QtlA3pVKD1tZXLDQWsHE4iP A==; X-IronPort-AV: E=McAfee;i="6500,9779,10636"; a="318455022" X-IronPort-AV: E=Sophos;i="5.98,227,1673942400"; d="scan'208";a="318455022" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Mar 2023 00:20:57 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10636"; a="743757591" X-IronPort-AV: E=Sophos;i="5.98,227,1673942400"; d="scan'208";a="743757591" Received: from srr4-3-linux-106-armuthy.iind.intel.com ([10.190.238.56]) by fmsmga004.fm.intel.com with ESMTP; 02 Mar 2023 00:20:56 -0800 From: Arun R Murthy To: intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, jani.nikula@intel.com Subject: [PATCHv4 2/2] i915/display/dp: SDP CRC16 for 128b132b link layer Date: Thu, 2 Mar 2023 13:45:32 +0530 Message-Id: <20230302081532.765821-3-arun.r.murthy@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230302081532.765821-1-arun.r.murthy@intel.com> References: <20230302081532.765821-1-arun.r.murthy@intel.com> MIME-Version: 1.0 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: Arun R Murthy Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Enable SDP error detection configuration, this will set CRC16 in 128b/132b link layer. For Display version 13 a hardware bit31 in register VIDEO_DIP_CTL is added to enable/disable SDP CRC applicable for DP2.0 only, but the default value of this bit will enable CRC16 in 128b/132b hence skipping this write. Corrective actions on SDP corruption is yet to be defined. v2: Moved the CRC enable to link training init(Jani N) v3: Moved crc enable to ddi pre enable v4: Separate function for SDP CRC16 (Jani N) Signed-off-by: Arun R Murthy Reviewed-by: Jani Nikula --- drivers/gpu/drm/i915/display/intel_ddi.c | 4 ++++ .../drm/i915/display/intel_dp_link_training.c | 20 +++++++++++++++++++ .../drm/i915/display/intel_dp_link_training.h | 2 ++ 3 files changed, 26 insertions(+) diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c index e5979427b38b..127b3035f92d 100644 --- a/drivers/gpu/drm/i915/display/intel_ddi.c +++ b/drivers/gpu/drm/i915/display/intel_ddi.c @@ -2519,6 +2519,10 @@ static void intel_ddi_pre_enable_dp(struct intel_atomic_state *state, { struct drm_i915_private *dev_priv = to_i915(encoder->base.dev); + if (HAS_DP20(dev_priv)) + intel_dp_128b132b_sdp_crc16(enc_to_intel_dp(encoder), + crtc_state); + if (DISPLAY_VER(dev_priv) >= 12) tgl_ddi_pre_enable_dp(state, encoder, crtc_state, conn_state); else diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.c b/drivers/gpu/drm/i915/display/intel_dp_link_training.c index 3d3efcf02011..35d31e4efab9 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c +++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c @@ -1454,3 +1454,23 @@ void intel_dp_start_link_train(struct intel_dp *intel_dp, if (!passed) intel_dp_schedule_fallback_link_training(intel_dp, crtc_state); } + +void intel_dp_128b132b_sdp_crc16(struct intel_dp *intel_dp, + const struct intel_crtc_state *crtc_state) +{ + struct drm_i915_private *i915 = dp_to_i915(intel_dp); + + /* + * VIDEO_DIP_CTL register bit 31 should be set to '0' to not + * disable SDP CRC. This is applicable for Display version 13. + * Default value of bit 31 is '0' hence discarding the write + * TODO: Corrective actions on SDP corruption yet to be defined + */ + if (intel_dp_is_uhbr(crtc_state)) + /* DP v2.0 SCR on SDP CRC16 for 128b/132b Link Layer */ + drm_dp_dpcd_writeb(&intel_dp->aux, + DP_SDP_ERROR_DETECTION_CONFIGURATION, + DP_SDP_CRC16_128B132B_EN); + + drm_dbg_kms(&i915->drm, "DP2.0 SDP CRC16 for 128b/132b enabled\n"); +} diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.h b/drivers/gpu/drm/i915/display/intel_dp_link_training.h index 7fa1c0833096..2c8f2775891b 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_link_training.h +++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.h @@ -39,4 +39,6 @@ static inline u8 intel_dp_training_pattern_symbol(u8 pattern) return pattern & ~DP_LINK_SCRAMBLING_DISABLE; } +void intel_dp_128b132b_sdp_crc16(struct intel_dp *intel_dp, + const struct intel_crtc_state *crtc_state); #endif /* __INTEL_DP_LINK_TRAINING_H__ */