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 DF27CC2D0B1 for ; Fri, 7 Feb 2020 06:40:37 +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 B4F002082E for ; Fri, 7 Feb 2020 06:40:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B4F002082E 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 156F46FB7F; Fri, 7 Feb 2020 06:40:37 +0000 (UTC) Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTPS id 813F56FB7F for ; Fri, 7 Feb 2020 06:40:35 +0000 (UTC) X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 06 Feb 2020 22:40:34 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,412,1574150400"; d="scan'208";a="264888756" Received: from ramaling-i9x.iind.intel.com (HELO intel.com) ([10.99.66.154]) by fmsmga002.fm.intel.com with ESMTP; 06 Feb 2020 22:40:33 -0800 Date: Fri, 7 Feb 2020 12:10:44 +0530 From: Ramalingam C To: Anshuman Gupta Message-ID: <20200207064044.GA9338@intel.com> References: <20200206150442.32353-1-anshuman.gupta@intel.com> <20200206150442.32353-2-anshuman.gupta@intel.com> <20200206170026.GA26821@intel.com> <20200206170928.GM24118@intel.com> <20200206173657.GD26821@intel.com> <20200206183013.GN24118@intel.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200206183013.GN24118@intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) Subject: Re: [Intel-gfx] [PATCH 1/2] drm/i915/hdcp: Fix 1B-06 HDCP2.2 Comp test 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: intel-gfx@lists.freedesktop.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On 2020-02-07 at 00:00:13 +0530, Anshuman Gupta wrote: > On 2020-02-06 at 23:06:57 +0530, Ramalingam C wrote: > > On 2020-02-06 at 22:39:28 +0530, Anshuman Gupta wrote: > > > On 2020-02-06 at 22:30:27 +0530, Ramalingam C wrote: > > > > On 2020-02-06 at 20:34:41 +0530, Anshuman Gupta wrote: > > > > > HDCP Repeater initializes seq_num_V to 0 at the beginning of > > > > > hdcp Session i.e. after AKE_init received. > > > > > > > > > > HDCP 2.2 Comp specs 1B-06 test verifies that whether DUT > > > > > considers failures of authentication if the repeater provides a > > > > > non-zero value in seq_num_V in the first, > > > > > RepeaterAuth_Send_ReceiverID_List message after first AKE_Init. > > > > > Fixing this broken test. > > > > Instead of "Fixing the broken test" could we say, we mandate the first > > > > seq_num_v to be zero? in fact i would keep this as commit subject also. > > > > > > > > > > Cc: Ramalingam C > > > > > Signed-off-by: Anshuman Gupta > > > > > --- > > > > > drivers/gpu/drm/i915/display/intel_display_types.h | 3 +++ > > > > > drivers/gpu/drm/i915/display/intel_hdcp.c | 13 +++++++++++++ > > > > > 2 files changed, 16 insertions(+) > > > > > > > > > > diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h > > > > > index 7ae0bc8b80d1..2ae540e986ba 100644 > > > > > --- a/drivers/gpu/drm/i915/display/intel_display_types.h > > > > > +++ b/drivers/gpu/drm/i915/display/intel_display_types.h > > > > > @@ -360,6 +360,9 @@ struct intel_hdcp { > > > > > /* HDCP2.2 Encryption status */ > > > > > bool hdcp2_encrypted; > > > > > > > > > > + /* Flag indicate if it is a first ReceiverID_List msg after AKE_Init */ > > > > > + bool first_recvid_msg; > > > > This extra flag is not needed, see below comment > > > > > + > > > > > /* > > > > > * Content Stream Type defined by content owner. TYPE0(0x0) content can > > > > > * flow in the link protected by HDCP2.2 or HDCP1.4, where as TYPE1(0x1) > > > > > diff --git a/drivers/gpu/drm/i915/display/intel_hdcp.c b/drivers/gpu/drm/i915/display/intel_hdcp.c > > > > > index 4d1a33d13105..3e24a6df503a 100644 > > > > > --- a/drivers/gpu/drm/i915/display/intel_hdcp.c > > > > > +++ b/drivers/gpu/drm/i915/display/intel_hdcp.c > > > > > @@ -1251,6 +1251,8 @@ static int hdcp2_authentication_key_exchange(struct intel_connector *connector) > > > > > size_t size; > > > > > int ret; > > > > > > > > > > + hdcp->first_recvid_msg = true; > > > > > + > > > > > /* Init for seq_num */ > > > > > hdcp->seq_num_v = 0; > > > > > hdcp->seq_num_m = 0; > > > > > @@ -1462,6 +1464,16 @@ int hdcp2_authenticate_repeater_topology(struct intel_connector *connector) > > > > > seq_num_v = > > > > > drm_hdcp_be24_to_cpu((const u8 *)msgs.recvid_list.seq_num_v); > > > > > > > > > > + /* > > > > > + * HDCP 2.2 Spec HDMI PAGE 19, DP PAGE 20 > > > > > + * HDCP 2.2 Comp 1B-06 test requires to disable encryption if there is > > > > > + * non zero seq_num_V from recevier. > > > > IMHO In commit message this kind of reasoning make sense, but here this is > > > > not needed. As every line in the file will be as per the spec so we dont > > > > need to call them out. > > > > > + */ > > > > > + if (hdcp->first_recvid_msg && seq_num_v) { > > > > if (!hdcp->seq_num_v && seq_num_v) { > > > > > > > > IMO This is all we need it. > > > I had tried this as my first solution, eventually this fill the link integrity check, see below. > > > > > > > > -Ram > > > > > + drm_dbg_kms(&dev_priv->drm, "Non zero Seq_num_v at beginning of HDCP Session\n"); > > > > > + return -EINVAL; > > > > > + } > > > > > + > > > > > if (seq_num_v < hdcp->seq_num_v) { > > > > > /* Roll over of the seq_num_v from repeater. Reauthenticate. */ > > > > > DRM_DEBUG_KMS("Seq_num_v roll over.\n"); > > > > > @@ -1484,6 +1496,7 @@ int hdcp2_authenticate_repeater_topology(struct intel_connector *connector) > > > > > return ret; > > > > > > > > > > hdcp->seq_num_v = seq_num_v; > > > seq_num_v will be zero for first session, which left hdcp->seq_num_v to zero and that will > > > fail the link intergrity check as at during link intergrity check seq_num_v will be non-zero, > > > this happens during 1B-09, when repeater topolgy changes due to Roll over of seq_num_v. > > > > topology update should increment the seq_num_v which will make it > than > > hdcp->seq_num_v. How roll over happens? And at every AKE start we init > > hdcp->seq_num_v to 0. > > > > So please elaborate the failure scenario. > Please refer to HDCP 2.2 spec page page 44 Step 1-B-09 > STEP 1B-09-01 > -> TE sets seq_num_V to 0xFFFFFFh Is it possible to randomly set seq_num_v to 0xFFFFFFh after 0? thought it is getting incremented by 1 for every topology change. > -> TE simulate disconnect of active downstream device by decrementing DEVICE_COUNT > *As I understand above will assert the READY bit that will detect as topology change and will make a call > to hdcp2_authenticate_repeater_topology() and there it will fail for > if (!hdcp->seq_num_v && seq_num_v) conidiation, and test will fail here itself. possible if the TE change the seq_num_v from 0 to ffffffh directly. Need to check whether that is ok to do? > -> DUT sends RepeaterAuth_Send_Ack message > STEP 1B-09-02 > -> TE will set seq_num_V to 0x000 to indicate Roll Over. > > Please correct me if i am wrong here. if not the hdcp->seq_num_v, you can use hdcp->value which will be ENABLED for repeated topology change or you can use hdcp->hdcp2_encrypted which will be true in above roll over case. Thanks, Ram. > > Thanks , > Anshuman Gupta. > > > > > Ram. > > > Thanks , > > > Anshuman Gupta. > > > > > > > > + hdcp->first_recvid_msg = false; > > > > > ret = shim->write_2_2_msg(intel_dig_port, &msgs.rep_ack, > > > > > sizeof(msgs.rep_ack)); > > > > > if (ret < 0) > > > > > -- > > > > > 2.24.0 > > > > > _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx