From patchwork Wed Dec 14 14:55:37 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Zanoni, Paulo R" X-Patchwork-Id: 9474319 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 891D16021C for ; Wed, 14 Dec 2016 14:55:48 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7BC3828713 for ; Wed, 14 Dec 2016 14:55:48 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 707DF28726; Wed, 14 Dec 2016 14:55:48 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 1D2B628713 for ; Wed, 14 Dec 2016 14:55:47 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E42E86E829; Wed, 14 Dec 2016 14:55:46 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by gabe.freedesktop.org (Postfix) with ESMTPS id 4CE0489A4B for ; Wed, 14 Dec 2016 14:55:45 +0000 (UTC) Received: from orsmga004.jf.intel.com ([10.7.209.38]) by orsmga105.jf.intel.com with ESMTP; 14 Dec 2016 06:55:44 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.33,347,1477983600"; d="scan'208";a="39913872" Received: from przanoni-mobl.amr.corp.intel.com ([10.254.182.181]) by orsmga004.jf.intel.com with ESMTP; 14 Dec 2016 06:55:43 -0800 From: Paulo Zanoni To: intel-gfx@lists.freedesktop.org Date: Wed, 14 Dec 2016 12:55:37 -0200 Message-Id: <1481727338-9901-1-git-send-email-paulo.r.zanoni@intel.com> X-Mailer: git-send-email 2.7.4 Cc: Paulo Zanoni , stable@vger.kernel.org Subject: [Intel-gfx] [PATCH 1/2] drm/i915: skip the first 4k of stolen memory on everything >= gen8 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-Virus-Scanned: ClamAV using ClamSMTP BSpec got updated and this workaround is now listed as standard required programming for all subsequent projects. This is confirmed to fix Skylake screen flickering issues (probably caused by the fact that we initialized a ring in the first page of stolen, but I didn't 100% confirm this theory). v2: this is the patch that fixes the screen flickering, document it. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=94605 Cc: stable@vger.kernel.org Tested-by: Dominik Klementowski Signed-off-by: Paulo Zanoni Acked-by: Chris Wilson --- drivers/gpu/drm/i915/i915_gem_stolen.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c index efc0e74..b1c8897 100644 --- a/drivers/gpu/drm/i915/i915_gem_stolen.c +++ b/drivers/gpu/drm/i915/i915_gem_stolen.c @@ -55,10 +55,9 @@ int i915_gem_stolen_insert_node_in_range(struct drm_i915_private *dev_priv, return -ENODEV; /* See the comment at the drm_mm_init() call for more about this check. - * WaSkipStolenMemoryFirstPage:bdw,chv,kbl (incomplete) + * WaSkipStolenMemoryFirstPage:bdw+ (incomplete) */ - if (start < 4096 && (IS_GEN8(dev_priv) || - IS_KBL_REVID(dev_priv, 0, KBL_REVID_A0))) + if (start < 4096 && INTEL_GEN(dev_priv) >= 8) start = 4096; mutex_lock(&dev_priv->mm.stolen_lock);