From patchwork Sat Apr 7 01:10:53 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Lyude Paul X-Patchwork-Id: 10327723 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 162FA6020F for ; Sat, 7 Apr 2018 01:11:10 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0CB6E2969A for ; Sat, 7 Apr 2018 01:11:10 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id F2E86296AE; Sat, 7 Apr 2018 01:11:09 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 97A1C2969A for ; Sat, 7 Apr 2018 01:11:08 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 121A96EAF1; Sat, 7 Apr 2018 01:11:05 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mx1.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by gabe.freedesktop.org (Postfix) with ESMTPS id 0AB446EAF1; Sat, 7 Apr 2018 01:11:03 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 606DC406E97C; Sat, 7 Apr 2018 01:11:00 +0000 (UTC) Received: from malachite.bss.redhat.com (dhcp-10-20-1-55.bss.redhat.com [10.20.1.55]) by smtp.corp.redhat.com (Postfix) with ESMTP id C86A7BDC56; Sat, 7 Apr 2018 01:10:56 +0000 (UTC) From: Lyude Paul To: intel-gfx@lists.freedesktop.org Subject: [PATCH v5] drm/i915/dp: Send DPCD ON for MST before phy_up Date: Fri, 6 Apr 2018 21:10:53 -0400 Message-Id: <20180407011053.22437-1-lyude@redhat.com> In-Reply-To: <20180406185249.22952-1-lyude@redhat.com> References: <20180406185249.22952-1-lyude@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Sat, 07 Apr 2018 01:11:00 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Sat, 07 Apr 2018 01:11:00 +0000 (UTC) for IP:'10.11.54.5' DOMAIN:'int-mx05.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'lyude@redhat.com' RCPT:'' X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: David Airlie , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Rodrigo Vivi , stable@vger.kernel.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP When doing a modeset where the sink is transitioning from D3 to D0 , it would sometimes be possible for the initial power_up_phy() to start timing out. This would only be observed in the last action before the sink went into D3 mode was intel_dp_sink_dpms(DRM_MODE_DPMS_OFF). We originally thought this might be an issue with us accidentally shutting off the aux block when putting the sink into D3, but since the DP spec mandates that sinks must wake up within 1ms while we have 100ms to respond to an ESI irq, this didn't really add up. Turns out that the problem is more subtle then that: It turns out that the timeout is from us not enabling DPMS on the MST hub before actually trying to initiate sideband communications. This would cause the first sideband communication (power_up_phy()), to start timing out because the sink wasn't ready to respond. Afterwards, we would call intel_dp_sink_dpms(DRM_MODE_DPMS_ON) in intel_ddi_pre_enable_dp(), which would actually result in waking up the sink so that sideband requests would work again. Since DPMS is what lets us actually bring the hub up into a state where sideband communications become functional again, we just need to make sure to enable DPMS on the display before attempting to perform sideband communications. Changes since v1: - Remove comment above if (!intel_dp->is_mst) - vsryjala - Move intel_dp_sink_dpms() for MST into intel_dp_post_disable_mst() to keep enable/disable paths symmetrical - Improve commit message - dhnkrn Changes since v2: - Only send DPMS off when we're disabling the last sink, and only send DPMS on when we're enabling the first sink - dhnkrn Changes since v3: - Check against is_mst, not intel_dp->is_mst - dhnkrn/vsyrjala Signed-off-by: Lyude Paul Reviewed-by: Dhinakaran Pandiyan Reviewed-by: Ville Syrjälä Tested-by: Laura Abbott Cc: stable@vger.kernel.org Fixes: ad260ab32a4d9 ("drm/i915/dp: Write to SET_POWER dpcd to enable MST hub.") --- No actual changes other than t-b and r-bs. Resending because I don't have access to the "test latest revision again" button and I'm very much sure these CI results are bogus. drivers/gpu/drm/i915/intel_ddi.c | 8 ++++++-- drivers/gpu/drm/i915/intel_dp_mst.c | 8 +++++++- 2 files changed, 13 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c index a6672a9abd85..92cb26b18a9b 100644 --- a/drivers/gpu/drm/i915/intel_ddi.c +++ b/drivers/gpu/drm/i915/intel_ddi.c @@ -2324,7 +2324,8 @@ static void intel_ddi_pre_enable_dp(struct intel_encoder *encoder, intel_prepare_dp_ddi_buffers(encoder, crtc_state); intel_ddi_init_dp_buf_reg(encoder); - intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_ON); + if (!is_mst) + intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_ON); intel_dp_start_link_train(intel_dp); if (port != PORT_A || INTEL_GEN(dev_priv) >= 9) intel_dp_stop_link_train(intel_dp); @@ -2422,12 +2423,15 @@ static void intel_ddi_post_disable_dp(struct intel_encoder *encoder, struct drm_i915_private *dev_priv = to_i915(encoder->base.dev); struct intel_digital_port *dig_port = enc_to_dig_port(&encoder->base); struct intel_dp *intel_dp = &dig_port->dp; + bool is_mst = intel_crtc_has_type(old_crtc_state, + INTEL_OUTPUT_DP_MST); /* * Power down sink before disabling the port, otherwise we end * up getting interrupts from the sink on detecting link loss. */ - intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_OFF); + if (!is_mst) + intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_OFF); intel_disable_ddi_buf(encoder); diff --git a/drivers/gpu/drm/i915/intel_dp_mst.c b/drivers/gpu/drm/i915/intel_dp_mst.c index c3de0918ee13..9e6956c08688 100644 --- a/drivers/gpu/drm/i915/intel_dp_mst.c +++ b/drivers/gpu/drm/i915/intel_dp_mst.c @@ -180,9 +180,11 @@ static void intel_mst_post_disable_dp(struct intel_encoder *encoder, intel_dp->active_mst_links--; intel_mst->connector = NULL; - if (intel_dp->active_mst_links == 0) + if (intel_dp->active_mst_links == 0) { + intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_OFF); intel_dig_port->base.post_disable(&intel_dig_port->base, old_crtc_state, NULL); + } DRM_DEBUG_KMS("active links %d\n", intel_dp->active_mst_links); } @@ -223,7 +225,11 @@ static void intel_mst_pre_enable_dp(struct intel_encoder *encoder, DRM_DEBUG_KMS("active links %d\n", intel_dp->active_mst_links); + if (intel_dp->active_mst_links == 0) + intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_ON); + drm_dp_send_power_updown_phy(&intel_dp->mst_mgr, connector->port, true); + if (intel_dp->active_mst_links == 0) intel_dig_port->base.pre_enable(&intel_dig_port->base, pipe_config, NULL);