From patchwork Tue Jun 24 22:12:50 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Todd Previte X-Patchwork-Id: 4414401 Return-Path: X-Original-To: patchwork-intel-gfx@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 1B24DBEEAA for ; Tue, 24 Jun 2014 22:13:36 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 5375720263 for ; Tue, 24 Jun 2014 22:13:35 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.kernel.org (Postfix) with ESMTP id 65BA320304 for ; Tue, 24 Jun 2014 22:13:34 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id DE7536E5B6; Tue, 24 Jun 2014 15:13:33 -0700 (PDT) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mail-pb0-f46.google.com (mail-pb0-f46.google.com [209.85.160.46]) by gabe.freedesktop.org (Postfix) with ESMTP id 6359E6E5B7 for ; Tue, 24 Jun 2014 15:13:32 -0700 (PDT) Received: by mail-pb0-f46.google.com with SMTP id md12so800052pbc.33 for ; Tue, 24 Jun 2014 15:13:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=sFnzGWQoxn4Jf4K0nSQZgJC9OHsWqvFuNIMQENCJ4Lc=; b=TKy3uPduuHze84ekowVEFT+pU0TqS0+cRg4SD2MtqPXxAveUGd/EH8xh8JPF/eE2Uj Qv8Dd2G2U7N7XOhYtsiY7ItJYtPueIwu7GZ8WVG53ei3GG75hDYUpyOwMGkyWcgKXVuf th3qkXUUYXECdxu2Q0L90LtpYkrglmaaKIWZA6hzWnpEWnM84YE6Le9fqOONy00pV/mE k9hb7dZDelXAIJSCrEQFqRqnr8QA6wSUC6et7GIa9LzjMp7edQ5OQGVSnOZgmPYHurhO IuBmwil2SFvs+vwWemlgsypeIPzKUSUSgmU2JdilkK0ACGKHnv6EwKF/ABlGiyiGwrs6 5cfw== X-Received: by 10.68.129.99 with SMTP id nv3mr5494309pbb.128.1403648012295; Tue, 24 Jun 2014 15:13:32 -0700 (PDT) Received: from localhost.localdomain (ip72-201-95-47.ph.ph.cox.net. [72.201.95.47]) by mx.google.com with ESMTPSA id bc4sm2023698pbb.2.2014.06.24.15.13.30 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 24 Jun 2014 15:13:31 -0700 (PDT) From: Todd Previte To: intel-gfx@lists.freedesktop.org Date: Tue, 24 Jun 2014 15:12:50 -0700 Message-Id: <1403647974-42377-3-git-send-email-tprevite@gmail.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1403647974-42377-1-git-send-email-tprevite@gmail.com> References: <1403647974-42377-1-git-send-email-tprevite@gmail.com> Subject: [Intel-gfx] [PATCH 2/6] drm/i915: Add a delay in Displayport AUX transactions for compliance testing X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Spam-Status: No, score=-4.1 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_MED, T_DKIM_INVALID, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Several compliance tests require that follow-up AUX transactions (after a failure or no response) are not resent sooner than 400us later. Add a 400us delay to the response time of any failed transaction to account for this. Signed-off-by: Todd Previte --- drivers/gpu/drm/i915/intel_dp.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 3bd1780..43fcabe 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -561,8 +561,12 @@ intel_dp_aux_ch(struct intel_dp *intel_dp, DP_AUX_CH_CTL_RECEIVE_ERROR); if (status & (DP_AUX_CH_CTL_TIME_OUT_ERROR | - DP_AUX_CH_CTL_RECEIVE_ERROR)) + DP_AUX_CH_CTL_RECEIVE_ERROR)) { + /* 400us delay between transactions for errors/timeouts + required for DP compliance testing */ + udelay(400); continue; + } if (status & DP_AUX_CH_CTL_DONE) break; }