From patchwork Thu Dec 12 19:02:22 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Sean Paul X-Patchwork-Id: 11289271 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id EA76714BD for ; Thu, 12 Dec 2019 19:02:59 +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 C94452073B for ; Thu, 12 Dec 2019 19:02:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=poorly.run header.i=@poorly.run header.b="PAWNwMTI" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C94452073B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=poorly.run Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id B40556E139; Thu, 12 Dec 2019 19:02:43 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail-yb1-xb41.google.com (mail-yb1-xb41.google.com [IPv6:2607:f8b0:4864:20::b41]) by gabe.freedesktop.org (Postfix) with ESMTPS id CD40B6E122 for ; Thu, 12 Dec 2019 19:02:40 +0000 (UTC) Received: by mail-yb1-xb41.google.com with SMTP id d34so877810yba.10 for ; Thu, 12 Dec 2019 11:02:40 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=poorly.run; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=B59JiOsuU+6Z9/Pg9GVc8XuLtqDK4voDlfHRSDfUne4=; b=PAWNwMTIuHWEgDR9kTy+FpwsTSz1dIB/KVdDITxkWFUyHgSe27uSFGSjE3bcxFZyM5 bA8qomdYKlt53zjA/P/oVyXDCbdQdtWOwY8Afnwh6UC+0989Lrg2O9XGunDr2MrGoZYF mbWDyXV1Swcd56EppeOUWifS823bcag1EUjdXcQxJ9WcOnpq1RLTyKS8efVTjHXMKxQ2 yS54bcRs9Q1pQcTlyuQPsX4zf98RU4ia9ytUV/QupJHwk91FtVUBMpsz/niEBL5azNcr CvMPFR3q+TPaL7hH66mSGNoOYClRr8XqUC2rxv67rMerll+ZGfsTPW2TlSlQYYJ8zX33 QMog== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=B59JiOsuU+6Z9/Pg9GVc8XuLtqDK4voDlfHRSDfUne4=; b=PAr8AcWsPXk0Jpk2JuFsn5AHhPa2uFO9EmBUCH/0ez7sBIULAq7yCXcqDJ4mIIs4pQ UD9BvRNK+XooLUCsgRn4I9Cgw4C/0mgNS+yYSQNRoHtPcHT7oxXRNRU+jwPU7Wom8DpR tK3KVq6Wi6KgJfXoJmKO+2g3bbLRNOBQLXeAAPz9GZzmmQZ1j323ve0pmt9s0krKf94f gR1iPRB2hRSSIGsQ+ctSvYHDI8mwHERYrMgEsySYaVDvgRdbOx7basLJ68r8voJTXn/H 5NfBofcv+Mw9Srk8lEsGWvytRCn3lopdntZqG57n5ntLKt45RGGfdsoh2A+rUqnpkphh gxmA== X-Gm-Message-State: APjAAAWq/Oe8hXTKw7dj0f5J/1tcXtKi2whUZ55hZjdNywV5UJ8Vwj58 b78Z6xAvrK0SDYoR5tPiIQZPKi5zxEkfhQ== X-Google-Smtp-Source: APXvYqw4gMcurZfgmKLdAoD2CYqI2lbNOMsl4PqpvVHdq0QKzC0/RGibuprwEIOIMDSfJJpRFowhhg== X-Received: by 2002:a25:7c45:: with SMTP id x66mr5034770ybc.297.1576177359525; Thu, 12 Dec 2019 11:02:39 -0800 (PST) Received: from localhost ([2620:0:1013:11:1e1:4760:6ce4:fc64]) by smtp.gmail.com with ESMTPSA id v38sm2618704ywh.63.2019.12.12.11.02.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 12 Dec 2019 11:02:39 -0800 (PST) From: Sean Paul To: dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org Subject: [PATCH v2 04/12] drm/i915: Intercept Aksv writes in the aux hooks Date: Thu, 12 Dec 2019 14:02:22 -0500 Message-Id: <20191212190230.188505-5-sean@poorly.run> X-Mailer: git-send-email 2.24.1.735.g03f4e72817-goog In-Reply-To: <20191212190230.188505-1-sean@poorly.run> References: <20191212190230.188505-1-sean@poorly.run> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: daniel.vetter@ffwll.ch, rodrigo.vivi@intel.com, Sean Paul Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: Sean Paul Instead of hand rolling the transfer ourselves in the hdcp hook, inspect aux messages and add the aksv flag in the aux transfer hook. IIRC, this was the original implementation and folks wanted this hack to be isolated to the hdcp code, which makes sense. However in testing an LG monitor on my desk, I noticed it was passing back a DEFER reply. This wasn't handled in our hand-rolled code and HDCP auth was failing as a result. Instead of copy/pasting all of the retry logic and delays from drm dp helpers, let's just use the helpers and hide the aksv select as best as we can. Reviewed-by: Ville Syrjälä Signed-off-by: Sean Paul Link: https://patchwork.freedesktop.org/patch/msgid/20191203173638.94919-3-sean@poorly.run #v1 Changes in v2: -Remove 'generate' in intel_dp_aux_generate_xfer_flags, make arg const (Ville) -Bundle Aksv if statement together (Ville) -Rename 'txbuf' to 'aksv' (Ville) Reviewed-by: Ramalingam C --- drivers/gpu/drm/i915/display/intel_dp.c | 62 ++++++++++++------------- 1 file changed, 29 insertions(+), 33 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c index fe31bbfd6c62..5576193b4fed 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.c +++ b/drivers/gpu/drm/i915/display/intel_dp.c @@ -1515,12 +1515,27 @@ intel_dp_aux_header(u8 txbuf[HEADER_SIZE], txbuf[3] = msg->size - 1; } +static u32 intel_dp_aux_xfer_flags(const struct drm_dp_aux_msg *msg) +{ + /* + * If we're trying to send the HDCP Aksv, we need to set a the Aksv + * select bit to inform the hardware to send the Aksv after our header + * since we can't access that data from software. + */ + if ((msg->request & ~DP_AUX_I2C_MOT) == DP_AUX_NATIVE_WRITE && + msg->address == DP_AUX_HDCP_AKSV) + return DP_AUX_CH_CTL_AUX_AKSV_SELECT; + + return 0; +} + static ssize_t intel_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg) { struct intel_dp *intel_dp = container_of(aux, struct intel_dp, aux); u8 txbuf[20], rxbuf[20]; size_t txsize, rxsize; + u32 flags = intel_dp_aux_xfer_flags(msg); int ret; intel_dp_aux_header(txbuf, msg); @@ -1541,7 +1556,7 @@ intel_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg) memcpy(txbuf + HEADER_SIZE, msg->buffer, msg->size); ret = intel_dp_aux_xfer(intel_dp, txbuf, txsize, - rxbuf, rxsize, 0); + rxbuf, rxsize, flags); if (ret > 0) { msg->reply = rxbuf[0] >> 4; @@ -1564,7 +1579,7 @@ intel_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg) return -E2BIG; ret = intel_dp_aux_xfer(intel_dp, txbuf, txsize, - rxbuf, rxsize, 0); + rxbuf, rxsize, flags); if (ret > 0) { msg->reply = rxbuf[0] >> 4; /* @@ -5904,17 +5919,9 @@ static int intel_dp_hdcp_write_an_aksv(struct intel_digital_port *intel_dig_port, u8 *an) { - struct intel_dp *intel_dp = enc_to_intel_dp(&intel_dig_port->base.base); - static const struct drm_dp_aux_msg msg = { - .request = DP_AUX_NATIVE_WRITE, - .address = DP_AUX_HDCP_AKSV, - .size = DRM_HDCP_KSV_LEN, - }; - u8 txbuf[HEADER_SIZE + DRM_HDCP_KSV_LEN] = {}, rxbuf[2], reply = 0; + u8 aksv[DRM_HDCP_KSV_LEN] = {}; ssize_t dpcd_ret; - int ret; - /* Output An first, that's easy */ dpcd_ret = drm_dp_dpcd_write(&intel_dig_port->dp.aux, DP_AUX_HDCP_AN, an, DRM_HDCP_AN_LEN); if (dpcd_ret != DRM_HDCP_AN_LEN) { @@ -5924,29 +5931,18 @@ int intel_dp_hdcp_write_an_aksv(struct intel_digital_port *intel_dig_port, } /* - * Since Aksv is Oh-So-Secret, we can't access it in software. So in - * order to get it on the wire, we need to create the AUX header as if - * we were writing the data, and then tickle the hardware to output the - * data once the header is sent out. + * Since Aksv is Oh-So-Secret, we can't access it in software. So we + * send an empty buffer of the correct length through the DP helpers. On + * the other side, in the transfer hook, we'll generate a flag based on + * the destination address which will tickle the hardware to output the + * Aksv on our behalf after the header is sent. */ - intel_dp_aux_header(txbuf, &msg); - - ret = intel_dp_aux_xfer(intel_dp, txbuf, HEADER_SIZE + msg.size, - rxbuf, sizeof(rxbuf), - DP_AUX_CH_CTL_AUX_AKSV_SELECT); - if (ret < 0) { - DRM_DEBUG_KMS("Write Aksv over DP/AUX failed (%d)\n", ret); - return ret; - } else if (ret == 0) { - DRM_DEBUG_KMS("Aksv write over DP/AUX was empty\n"); - return -EIO; - } - - reply = (rxbuf[0] >> 4) & DP_AUX_NATIVE_REPLY_MASK; - if (reply != DP_AUX_NATIVE_REPLY_ACK) { - DRM_DEBUG_KMS("Aksv write: no DP_AUX_NATIVE_REPLY_ACK %x\n", - reply); - return -EIO; + dpcd_ret = drm_dp_dpcd_write(&intel_dig_port->dp.aux, DP_AUX_HDCP_AKSV, + aksv, DRM_HDCP_KSV_LEN); + if (dpcd_ret != DRM_HDCP_KSV_LEN) { + DRM_DEBUG_KMS("Failed to write Aksv over DP/AUX (%zd)\n", + dpcd_ret); + return dpcd_ret >= 0 ? -EIO : dpcd_ret; } return 0; }