From patchwork Wed Nov 26 03:17:22 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dave Airlie X-Patchwork-Id: 5383841 Return-Path: X-Original-To: patchwork-intel-gfx@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 67B559F2F5 for ; Wed, 26 Nov 2014 03:17:31 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 8E1C1201EC for ; Wed, 26 Nov 2014 03:17:30 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.kernel.org (Postfix) with ESMTP id 5F38B201BC for ; Wed, 26 Nov 2014 03:17:29 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 2F8EA6E141; Tue, 25 Nov 2014 19:17:27 -0800 (PST) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by gabe.freedesktop.org (Postfix) with ESMTP id 294666E141; Tue, 25 Nov 2014 19:17:26 -0800 (PST) Received: from int-mx13.intmail.prod.int.phx2.redhat.com (int-mx13.intmail.prod.int.phx2.redhat.com [10.5.11.26]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id sAQ3HPlN013379 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Tue, 25 Nov 2014 22:17:25 -0500 Received: from tyrion-bne-redhat-com.bne.redhat.com (dhcp-40-110.bne.redhat.com [10.64.40.110]) by int-mx13.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id sAQ3HNQS003214; Tue, 25 Nov 2014 22:17:24 -0500 From: Dave Airlie To: dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org Date: Wed, 26 Nov 2014 13:17:22 +1000 Message-Id: <1416971843-2122-1-git-send-email-airlied@gmail.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.26 Subject: [Intel-gfx] [PATCH 1/2] drm/dp: retry AUX transactions 32 times X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.18 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=-4.2 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, FREEMAIL_FROM,RCVD_IN_DNSWL_MED,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 From: Dave Airlie At least on two MST devices I've tested with, when they are link training downstream, they are totally unable to handle aux ch msgs, so they defer like nuts. I tried 16, it wasn't enough, 32 seems better. This fixes one Dell 4k monitor and one of the MST hubs. Signed-off-by: Dave Airlie --- drivers/gpu/drm/drm_dp_helper.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index 959e207..db0993f 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -189,7 +189,7 @@ static int drm_dp_dpcd_access(struct drm_dp_aux *aux, u8 request, * retry native transactions, so retry 7 times like for I2C-over-AUX * transactions. */ - for (retry = 0; retry < 7; retry++) { + for (retry = 0; retry < 32; retry++) { mutex_lock(&aux->hw_mutex); err = aux->transfer(aux, &msg);