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 0DD7FC6FD1F for ; Thu, 16 Mar 2023 13:40:27 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 6597D10E1DF; Thu, 16 Mar 2023 13:40:25 +0000 (UTC) Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by gabe.freedesktop.org (Postfix) with ESMTPS id 0EA3410E1DF for ; Thu, 16 Mar 2023 13:40:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1678974021; x=1710510021; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=9bxrEkoTLlUig4XlVAYfbhXWpvaxHrLHWohmYT4zaSY=; b=Ul/LoUoYNQI2XWAlq29GLbPjqkTRbvchh5IFWXBvqtihSNdYHbO1bWsG wIMxzl3nwg9X6XkSmuRFnpeMmTby8XuTbSG1jiO4LG8SOTsfz9C0zrcxl L1YnzZFWdOC+pDR1vep+dcW1ESktyO41kxQhZTU65r7V9zL93r5eESvtH B89hQPRP6Pz9wYvTirC6Hdj3rYSC0+vdJHVTeVQOsGQcl0+JamPHFS46S bHY5Y6r7NGfLhNVeNOTkYaqCrCNpv8ZTXstSsVX/p6cRzxxARtgGfZbC2 /0pxAFu9GhUpsu5E209sDPAqIIt9mmWRwdqxrMspDg+iuf6/s1LYQHDQ7 w==; X-IronPort-AV: E=McAfee;i="6600,9927,10651"; a="339524596" X-IronPort-AV: E=Sophos;i="5.98,265,1673942400"; d="scan'208";a="339524596" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Mar 2023 06:17:28 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10650"; a="657171262" X-IronPort-AV: E=Sophos;i="5.98,265,1673942400"; d="scan'208";a="657171262" Received: from ideak-desk.fi.intel.com ([10.237.72.58]) by orsmga006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Mar 2023 06:17:27 -0700 From: Imre Deak To: intel-gfx@lists.freedesktop.org Date: Thu, 16 Mar 2023 15:17:11 +0200 Message-Id: <20230316131724.359612-2-imre.deak@intel.com> X-Mailer: git-send-email 2.31.1.189.g2e36527f23 In-Reply-To: <20230316131724.359612-1-imre.deak@intel.com> References: <20230316131724.359612-1-imre.deak@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: [Intel-gfx] [PATCH 01/14] drm/i915/tc: Abort DP AUX transfer on a disconnected TC port 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: , Cc: Chris Chiu Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On TC ports the 4ms AUX timeout combined with the 5 * 32 retry attempts during DPCD accesses adds a 640ms delay to each access if the sink is disconnected. This in turn slows down a modeset during which the sink is disconnected (for instance a disabling modeset). Prevent the above delay by aborting AUX transfers on a TC port with a disconnected sink. The DP 1.4a link CTS (4.2.1.5 Source Device Inactive HPD / Inactive AUX Test") also requires not to initiate AUX transfers on disconnected DP ports in general, however this patch doesn't change the behavior on non-TC ports, leaving that for a follow-up. Reported-and-tested-by: Chris Chiu Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/8279 Signed-off-by: Imre Deak --- drivers/gpu/drm/i915/display/intel_dp_aux.c | 15 +++++++++++++-- drivers/gpu/drm/i915/display/intel_tc.c | 15 +++++++++++---- drivers/gpu/drm/i915/display/intel_tc.h | 1 + 3 files changed, 25 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux.c b/drivers/gpu/drm/i915/display/intel_dp_aux.c index 96967e21c94c2..eb07dc5d87099 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_aux.c +++ b/drivers/gpu/drm/i915/display/intel_dp_aux.c @@ -205,8 +205,19 @@ intel_dp_aux_xfer(struct intel_dp *intel_dp, for (i = 0; i < ARRAY_SIZE(ch_data); i++) ch_data[i] = intel_dp->aux_ch_data_reg(intel_dp, i); - if (is_tc_port) + if (is_tc_port) { intel_tc_port_lock(dig_port); + /* + * Abort transfers on a disconnected port as required by + * DP 1.4a link CTS 4.2.1.5, also avoiding the long AUX + * timeouts that would otherwise happen. + * TODO: abort the transfer on non-TC ports as well. + */ + if (!intel_tc_port_connected_locked(&dig_port->base)) { + ret = -ENXIO; + goto out_unlock; + } + } aux_domain = intel_aux_power_domain(dig_port); @@ -367,7 +378,7 @@ intel_dp_aux_xfer(struct intel_dp *intel_dp, intel_pps_unlock(intel_dp, pps_wakeref); intel_display_power_put_async(i915, aux_domain, aux_wakeref); - +out_unlock: if (is_tc_port) intel_tc_port_unlock(dig_port); diff --git a/drivers/gpu/drm/i915/display/intel_tc.c b/drivers/gpu/drm/i915/display/intel_tc.c index f45328712bff1..050f998284592 100644 --- a/drivers/gpu/drm/i915/display/intel_tc.c +++ b/drivers/gpu/drm/i915/display/intel_tc.c @@ -768,16 +768,23 @@ void intel_tc_port_sanitize_mode(struct intel_digital_port *dig_port) * connected ports are usable, and avoids exposing to the users objects they * can't really use. */ +bool intel_tc_port_connected_locked(struct intel_encoder *encoder) +{ + struct intel_digital_port *dig_port = enc_to_dig_port(encoder); + struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev); + + drm_WARN_ON(&i915->drm, !intel_tc_port_ref_held(dig_port)); + + return tc_port_live_status_mask(dig_port) & BIT(dig_port->tc_mode); +} + bool intel_tc_port_connected(struct intel_encoder *encoder) { struct intel_digital_port *dig_port = enc_to_dig_port(encoder); bool is_connected; intel_tc_port_lock(dig_port); - - is_connected = tc_port_live_status_mask(dig_port) & - BIT(dig_port->tc_mode); - + is_connected = intel_tc_port_connected_locked(encoder); intel_tc_port_unlock(dig_port); return is_connected; diff --git a/drivers/gpu/drm/i915/display/intel_tc.h b/drivers/gpu/drm/i915/display/intel_tc.h index d54082e2d5e8d..93813056043a5 100644 --- a/drivers/gpu/drm/i915/display/intel_tc.h +++ b/drivers/gpu/drm/i915/display/intel_tc.h @@ -17,6 +17,7 @@ bool intel_tc_port_in_dp_alt_mode(struct intel_digital_port *dig_port); bool intel_tc_port_in_legacy_mode(struct intel_digital_port *dig_port); bool intel_tc_port_connected(struct intel_encoder *encoder); +bool intel_tc_port_connected_locked(struct intel_encoder *encoder); u32 intel_tc_port_get_lane_mask(struct intel_digital_port *dig_port); u32 intel_tc_port_get_pin_assignment_mask(struct intel_digital_port *dig_port); -- 2.37.1