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 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 2C437E9B25A for ; Wed, 25 Feb 2026 06:12:44 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id BA3B810E6AD; Wed, 25 Feb 2026 06:12:42 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="XX99Edc8"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.9]) by gabe.freedesktop.org (Postfix) with ESMTPS id 66EED10E6AC; Wed, 25 Feb 2026 06:12:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1771999962; x=1803535962; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=agAf3zLSg1dL3SGR0AcIQC4xEvRmZ7WjFEteeTzP78w=; b=XX99Edc84j2U4r86cf29IJ7NgjHRk+7VTiOvpFAvhvLda1o5bOGFEypS abYwqELujTwDRSVXHbp588YZgmt6xEd+NKx2xNOiFZht27iIuwAG/vYF5 MwMbcFtz4G7ACUYhCnr9FopRH25SyQgq1O5A4Be2iCOkdTTde9xFZ843w 8E8qbFkIBobDyrFZVVfJr9PEx3vNrtJuxGTFvY16tEZsLP2K3h+SCue4L sg7lbDaDbgVUFkGxbNPwaVxSAk0sT5nl7Ygq4+7BlxI14xweFHbwls6p+ DkGL9wzKRZzrdUjE7of529d4aRiVSmYHgCEv6yr9AycNx4WXvRA+mnXoE w==; X-CSE-ConnectionGUID: CMr7qyOUR3ivdufAgGpCHg== X-CSE-MsgGUID: m6BGQUGuTQySu3YUrJN8fg== X-IronPort-AV: E=McAfee;i="6800,10657,11711"; a="83743187" X-IronPort-AV: E=Sophos;i="6.21,310,1763452800"; d="scan'208";a="83743187" Received: from orviesa009.jf.intel.com ([10.64.159.149]) by fmvoesa103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Feb 2026 22:12:41 -0800 X-CSE-ConnectionGUID: PWd7lFObQNeXaoLc4ynPPw== X-CSE-MsgGUID: 8ckzRfj3TxmOnOUhAbdtrQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.21,310,1763452800"; d="scan'208";a="216016884" Received: from srr4-3-linux-106-armuthy.iind.intel.com ([10.190.238.56]) by orviesa009.jf.intel.com with ESMTP; 24 Feb 2026 22:12:39 -0800 From: Arun R Murthy To: intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org Cc: imre.deak@intel.com, suraj.kandpal@intel.com, jani.nikula@intel.com, ville.syrjala@linux.intel.com, Arun R Murthy Subject: [PATCHv3] drm/i915/dp: On DPCD init wake the DPRx for eDP Date: Wed, 25 Feb 2026 11:41:10 +0530 Message-Id: <20260225061110.385441-1-arun.r.murthy@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20260219094326.34922-1-arun.r.murthy@intel.com> References: <20260219094326.34922-1-arun.r.murthy@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: intel-xe@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Xe graphics driver List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-xe-bounces@lists.freedesktop.org Sender: "Intel-xe" Its observed that on AUX_CH failure, even if the retry is increased to 1000, it does not succeed. Either the command might be wrong or sink in an unknown/sleep state can cause this. So try waking the sink device. Before reading the DPCD caps wake the sink for eDP. v2: Use poll_timeout_us (Jani N) Add the reason, why this change is required (Ville) v3: Wake sink only for eDP Remove the dpcd probe set to true/false in wake_sink (Imre) Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/4391 Signed-off-by: Arun R Murthy --- drivers/gpu/drm/i915/display/intel_dp.c | 34 +++++++++++++++++++++++++ drivers/gpu/drm/i915/display/intel_dp.h | 1 + 2 files changed, 35 insertions(+) diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c index 025e906b63a9..38ea4aad74de 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.c +++ b/drivers/gpu/drm/i915/display/intel_dp.c @@ -4705,6 +4705,38 @@ intel_edp_set_sink_rates(struct intel_dp *intel_dp) intel_edp_set_data_override_rates(intel_dp); } +/* Spec says to try for 3 times, its doubled to add the software overhead */ +#define AUX_CH_WAKE_RETRY 6 + +void intel_dp_wake_sink(struct intel_dp *intel_dp) +{ + u8 value = 0; + int ret = 0; + + /* + * Wake the sink device + * Spec DP2.1 section 2.3.1.2 if AUX CH is powered down by writing 0x02 + * to DP_SET_POWER dpcd reg, 1ms time would be required to wake it up + */ + ret = poll_timeout_us(ret = drm_dp_dpcd_readb(&intel_dp->aux, DP_SET_POWER, &value), + ret > 0, + 1000, AUX_CH_WAKE_RETRY * 1000, true); + + /* + * If sink is in D3 then it may not respond to the AUX tx so + * wake it up to D3_AUX_ON state + * If the above poll_timeout_us fails, try waking the sink. + */ + if (value == DP_SET_POWER_D3 || ret < 0) { + /* After setting to D0 need a min of 1ms to wake(Spec DP2.1 sec 2.3.1.2) */ + drm_dp_dpcd_writeb(&intel_dp->aux, DP_SET_POWER, + DP_SET_POWER_D0); + fsleep(1000); + drm_dp_dpcd_writeb(&intel_dp->aux, DP_SET_POWER, + DP_SET_POWER_D3_AUX_ON); + } +} + static bool intel_edp_init_dpcd(struct intel_dp *intel_dp, struct intel_connector *connector) { @@ -4713,6 +4745,8 @@ intel_edp_init_dpcd(struct intel_dp *intel_dp, struct intel_connector *connector /* this function is meant to be called only once */ drm_WARN_ON(display->drm, intel_dp->dpcd[DP_DPCD_REV] != 0); + intel_dp_wake_sink(intel_dp); + if (drm_dp_read_dpcd_caps(&intel_dp->aux, intel_dp->dpcd) != 0) return false; diff --git a/drivers/gpu/drm/i915/display/intel_dp.h b/drivers/gpu/drm/i915/display/intel_dp.h index b0bbd5981f57..3f16077c0cc7 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.h +++ b/drivers/gpu/drm/i915/display/intel_dp.h @@ -232,6 +232,7 @@ bool intel_dp_dotclk_valid(struct intel_display *display, bool intel_dp_joiner_candidate_valid(struct intel_connector *connector, int hdisplay, int num_joined_pipes); +void intel_dp_wake_sink(struct intel_dp *intel_dp); #define for_each_joiner_candidate(__connector, __mode, __num_joined_pipes) \ for ((__num_joined_pipes) = 1; (__num_joined_pipes) <= (I915_MAX_PIPES); (__num_joined_pipes)++) \ -- 2.25.1