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 X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 12061C47259 for ; Tue, 5 May 2020 12:12:26 +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 DEEF4206B9 for ; Tue, 5 May 2020 12:12:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DEEF4206B9 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 7949A6E22A; Tue, 5 May 2020 12:12:25 +0000 (UTC) Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by gabe.freedesktop.org (Postfix) with ESMTPS id D6BF36E245 for ; Tue, 5 May 2020 12:12:24 +0000 (UTC) IronPort-SDR: 2zopcHQ+pzNkjTmHGynHCxRKAPNbhDGBPIQcPddYcHjyAd4xWr6HNzWtlFkY5LWmfiweIr9sbR xlDuWNlxDrTA== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 May 2020 05:12:23 -0700 IronPort-SDR: el6RNy4QFObAOFudjdExSrzECZMaxUAwj4u6VBB11VKsBibPmW7Xyw7OiUzrkL5f4RbR94Bmsj D2gSITG4o3dQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,354,1583222400"; d="scan'208";a="461018966" Received: from ramaling-i9x.iind.intel.com (HELO intel.com) ([10.99.66.154]) by fmsmga005.fm.intel.com with ESMTP; 05 May 2020 05:12:20 -0700 Date: Tue, 5 May 2020 17:42:13 +0530 From: Ramalingam C To: Oliver Barta Message-ID: <20200505121213.GA24840@intel.com> References: <20200504123524.7731-1-oliver.barta@aptiv.com> <20200505073809.GA24093@intel.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Subject: Re: [Intel-gfx] [PATCH] drm/i915: HDCP: retry link integrity check on failure 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: Daniel Vetter , Intel Graphics Development , Chris Wilson , Sean Paul , Oliver Barta , Ravisankar Madasamy Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On 2020-05-05 at 14:06:51 +0200, Oliver Barta wrote: > On Tue, May 5, 2020 at 9:38 AM Ramalingam C wrote: > > > > On 2020-05-04 at 14:35:24 +0200, Oliver Barta wrote: > > > From: Oliver Barta > > > > > > A single Ri mismatch doesn't automatically mean that the link integrity > > > is broken. Update and check of Ri and Ri' are done asynchronously. In > > > case an update happens just between the read of Ri' and the check against > > > Ri there will be a mismatch even if the link integrity is fine otherwise. > > > > Thanks for working on this. Btw, did you face this sporadic link check > > failure or theoretically you are fixing it? > > > > IMO this change will rule out possible sporadic link check failures as > > mentioned in the commit msg. Though I haven't faced this issue at my > > testings. > > > > Reviewed-by: Ramalingam C > > > > I found it by code inspection, the probability for this to happen is > very low. In order to test the patch I'm decreasing the value of > DRM_HDCP_CHECK_PERIOD_MS to just a few ms. Once you do that it happens > every few seconds. Ok. That make sense. Thanks for the explanation. -Ram > > Thanks, > Oliver > > > > > > > Signed-off-by: Oliver Barta > > > --- > > > drivers/gpu/drm/i915/display/intel_hdmi.c | 19 ++++++++++++++++--- > > > 1 file changed, 16 insertions(+), 3 deletions(-) > > > > > > diff --git a/drivers/gpu/drm/i915/display/intel_hdmi.c b/drivers/gpu/drm/i915/display/intel_hdmi.c > > > index 010f37240710..3156fde392f2 100644 > > > --- a/drivers/gpu/drm/i915/display/intel_hdmi.c > > > +++ b/drivers/gpu/drm/i915/display/intel_hdmi.c > > > @@ -1540,7 +1540,7 @@ int intel_hdmi_hdcp_toggle_signalling(struct intel_digital_port *intel_dig_port, > > > } > > > > > > static > > > -bool intel_hdmi_hdcp_check_link(struct intel_digital_port *intel_dig_port) > > > +bool intel_hdmi_hdcp_check_link_once(struct intel_digital_port *intel_dig_port) > > > { > > > struct drm_i915_private *i915 = to_i915(intel_dig_port->base.base.dev); > > > struct intel_connector *connector = > > > @@ -1563,8 +1563,7 @@ bool intel_hdmi_hdcp_check_link(struct intel_digital_port *intel_dig_port) > > > if (wait_for((intel_de_read(i915, HDCP_STATUS(i915, cpu_transcoder, port)) & > > > (HDCP_STATUS_RI_MATCH | HDCP_STATUS_ENC)) == > > > (HDCP_STATUS_RI_MATCH | HDCP_STATUS_ENC), 1)) { > > > - drm_err(&i915->drm, > > > - "Ri' mismatch detected, link check failed (%x)\n", > > > + drm_dbg_kms(&i915->drm, "Ri' mismatch detected (%x)\n", > > > intel_de_read(i915, HDCP_STATUS(i915, cpu_transcoder, > > > port))); > > > return false; > > > @@ -1572,6 +1571,20 @@ bool intel_hdmi_hdcp_check_link(struct intel_digital_port *intel_dig_port) > > > return true; > > > } > > > > > > +static > > > +bool intel_hdmi_hdcp_check_link(struct intel_digital_port *intel_dig_port) > > > +{ > > > + struct drm_i915_private *i915 = to_i915(intel_dig_port->base.base.dev); > > > + int retry; > > > + > > > + for (retry = 0; retry < 3; retry++) > > > + if (intel_hdmi_hdcp_check_link_once(intel_dig_port)) > > > + return true; > > > + > > > + drm_err(&i915->drm, "Link check failed\n"); > > > + return false; > > > +} > > > + > > > struct hdcp2_hdmi_msg_timeout { > > > u8 msg_id; > > > u16 timeout; > > > -- > > > 2.20.1 > > > _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx