From patchwork Wed Aug 1 10:47:21 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 10552087 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 861A1174A for ; Wed, 1 Aug 2018 10:47:36 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 75F1928E7C for ; Wed, 1 Aug 2018 10:47:36 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6A3F429E2C; Wed, 1 Aug 2018 10:47:36 +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=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, 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 5581728E7C for ; Wed, 1 Aug 2018 10:47:35 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 9F7066E2AF; Wed, 1 Aug 2018 10:47:34 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from fireflyinternet.com (mail.fireflyinternet.com [109.228.58.192]) by gabe.freedesktop.org (Postfix) with ESMTPS id 8F9066E2AF for ; Wed, 1 Aug 2018 10:47:32 +0000 (UTC) X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Received: from haswell.alporthouse.com (unverified [78.156.65.138]) by fireflyinternet.com (Firefly Internet (M1)) with ESMTP id 12532648-1500050 for multiple; Wed, 01 Aug 2018 11:47:23 +0100 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Wed, 1 Aug 2018 11:47:21 +0100 Message-Id: <20180801104721.4030-1-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180801100528.29866-1-chris@chris-wilson.co.uk> References: <20180801100528.29866-1-chris@chris-wilson.co.uk> Subject: [Intel-gfx] [PATCH] drm/i95: Mark GGTT as incoherent for gen10+ X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.23 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 The evidence suggests that we need to start treating writes via GGTT as incoherent for gen10+, that is that they are internally buffered and not immediately visible via a read along a different physical path. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=107398 Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=107400 Signed-off-by: Chris Wilson Cc: Mika Kuoppala Reviewed-by: Mika Kuoppala --- drivers/gpu/drm/i915/i915_pci.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/gpu/drm/i915/i915_pci.c b/drivers/gpu/drm/i915/i915_pci.c index e443fe44da3a..adf80563d0a1 100644 --- a/drivers/gpu/drm/i915/i915_pci.c +++ b/drivers/gpu/drm/i915/i915_pci.c @@ -590,6 +590,7 @@ static const struct intel_device_info intel_coffeelake_gt3_info = { GEN9_FEATURES, \ GEN(10), \ .ddb_size = 1024, \ + .has_coherent_ggtt = false, \ GLK_COLORS static const struct intel_device_info intel_cannonlake_info = {