From patchwork Thu Aug 4 07:43:53 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 9262867 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 3336A6048F for ; Thu, 4 Aug 2016 07:44:12 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 26FD528326 for ; Thu, 4 Aug 2016 07:44:12 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 1A13B2832B; Thu, 4 Aug 2016 07:44:12 +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=-4.1 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_MED,T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id EA21028326 for ; Thu, 4 Aug 2016 07:44:10 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 8A54B6E59E; Thu, 4 Aug 2016 07:44:06 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mail-wm0-x241.google.com (mail-wm0-x241.google.com [IPv6:2a00:1450:400c:c09::241]) by gabe.freedesktop.org (Postfix) with ESMTPS id 619866E59E for ; Thu, 4 Aug 2016 07:44:02 +0000 (UTC) Received: by mail-wm0-x241.google.com with SMTP id o80so41145189wme.0 for ; Thu, 04 Aug 2016 00:44:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=6w+ncEYGvdp5/qbS9n5/74aDdehX76w4tDg3Nv+7sXA=; b=jOyuUJZfgG8m1MqZXCC9JTVDS37Agzu0aV0eqUJCu4vzKEU4swDnxx8icMxExQzHJN wJR4qvTlXHuXUkrw4W9topzyTsKmfWVCEGbpngQJHTRIVFQOlUaUb8FzwDDn/5BwSQ7w 7sti4ZwLChcuMhL4R6jqLGcRZ5RxkgKTMzZzpvnUl5GZ6UTVN+mT3ZKNDTrjRmGBwAaA tyygJD/kBQA4KCQTOuJDZTKpIeYo8FcTSFa+Dt2YDKYJKTZ+vmDefO0wKFeGKexmqrp6 22ZEWDMy3aQNHu/z3gldcd4KfxAKOls/Y+lbF2l5c2XdYZN+qusEIXwNgvHFDHXWtuyj Y+jA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:sender:from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-transfer-encoding; bh=6w+ncEYGvdp5/qbS9n5/74aDdehX76w4tDg3Nv+7sXA=; b=fJAsqOlB2hfaDvcTrYpXShRP6KPwX/eE27ymts0WZ4Bv9h9dgvy/E2yzm49WTwEwij piW7U7oBgDZY8iweqjdZPHwdOI3eBQPuCsNMtZfcWkg24zA1UCoa+7MqTlr+8REPqpzQ hsckT8rjEn+xi+AjjjW9NEccyriTP0rok7txT1rpo8E84E0aAKooXfTyEkPzXvlW7pZM AEIYbewxBrTWE4SRC9jGUbPhQh6f6eLlwkpjMM8HgNQ3myTMmyUrxKdgzFfBrozMPEr7 YOq/st6ve6GPtbXpXXWAYsIwcolkwUKCEnB9w9daRQ5wOuD9jCMgJt+VDQbE6N+5y42M 24aQ== X-Gm-Message-State: AEkoouuRLBpYGKK9GoPlKxWDVkVtuggsrDr2rq+e7f9qqCNEVzeG4J9Q65AyjB+I9j5J2A== X-Received: by 10.28.166.140 with SMTP id p134mr27119498wme.21.1470296639878; Thu, 04 Aug 2016 00:43:59 -0700 (PDT) Received: from haswell.alporthouse.com ([78.156.65.138]) by smtp.gmail.com with ESMTPSA id u125sm2206319wmg.22.2016.08.04.00.43.57 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 04 Aug 2016 00:43:58 -0700 (PDT) From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Thu, 4 Aug 2016 08:43:53 +0100 Message-Id: <1470296633-20388-1-git-send-email-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.8.1 In-Reply-To: <20160804071434.GX4329@intel.com> References: <20160804071434.GX4329@intel.com> MIME-Version: 1.0 Cc: stable@vger.kernel.org, Paulo Zanoni Subject: [Intel-gfx] [PATCH v3] drm/i915/fbc: FBC causes display flicker when VT-d is enabled on Skylake 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: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Virus-Scanned: ClamAV using ClamSMTP Erratum SKL075: Display Flicker May Occur When Both VT-d And FBC Are Enabled "Display flickering may occur when both FBC (Frame Buffer Compression) and VT - d (Intel® Virtualization Technology for Directed I/O) are enabled and in use by the display controller." Ville found the w/a name in the database: WaFbcTurnOffFbcWhenHyperVisorIsUsed:skl,bxt and also dug out that it affects Broxton. v2: Log when the quirk is applied. v3: Ensure i915.enable_fbc is false when !HAS_FBC() v4: Fix function name after rebase v5: Add Broxton to the workaround Note for backporting to stable, we need to add ((struct intel_device_info *)INTEL_INFO(ptr)) Signed-off-by: Chris Wilson Cc: Paulo Zanoni Cc: Ville Syrjälä Reviewed-by: Ville Syrjälä Cc: stable@vger.kernel.org --- drivers/gpu/drm/i915/intel_fbc.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_fbc.c b/drivers/gpu/drm/i915/intel_fbc.c index 8147eb9e8475..d4be07615aa9 100644 --- a/drivers/gpu/drm/i915/intel_fbc.c +++ b/drivers/gpu/drm/i915/intel_fbc.c @@ -1229,12 +1229,29 @@ static int intel_sanitize_fbc_option(struct drm_i915_private *dev_priv) if (i915.enable_fbc >= 0) return !!i915.enable_fbc; + if (!HAS_FBC(dev_priv)) + return 0; + if (IS_BROADWELL(dev_priv)) return 1; return 0; } +static bool need_fbc_vtd_wa(struct drm_i915_private *dev_priv) +{ +#ifdef CONFIG_INTEL_IOMMU + /* WaFbcTurnOffFbcWhenHyperVisorIsUsed:skl,bxt */ + if (intel_iommu_gfx_mapped && + (IS_SKYLAKE(dev_priv) || IS_BROXTON(dev_priv))) { + DRM_INFO("Disabling framebuffer compression (FBC) to prevent screen flicker with VT-d enabled\n"); + return true; + } +#endif + + return false; +} + /** * intel_fbc_init - Initialize FBC * @dev_priv: the i915 device @@ -1252,6 +1269,9 @@ void intel_fbc_init(struct drm_i915_private *dev_priv) fbc->active = false; fbc->work.scheduled = false; + if (need_fbc_vtd_wa(dev_priv)) + mkwrite_device_info(dev_priv)->has_fbc = false; + i915.enable_fbc = intel_sanitize_fbc_option(dev_priv); DRM_DEBUG_KMS("Sanitized enable_fbc value: %d\n", i915.enable_fbc);