From patchwork Thu Sep 12 07:09:24 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 11142459 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 739A2924 for ; Thu, 12 Sep 2019 07:09:43 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5BE0E222C4 for ; Thu, 12 Sep 2019 07:09:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5BE0E222C4 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=chris-wilson.co.uk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id B4C736EBE5; Thu, 12 Sep 2019 07:09:42 +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 5429E6EBE5 for ; Thu, 12 Sep 2019 07:09:41 +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 18459539-1500050 for multiple; Thu, 12 Sep 2019 08:09:28 +0100 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Thu, 12 Sep 2019 08:09:24 +0100 Message-Id: <20190912070925.11526-1-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.23.0 MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH 1/2] drm/i915/execlists: Add a paranoid flush of the CSB pointers upon reset 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: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" After a GPU reset, we need to drain all the CS events so that we have an accurate picture of the execlists state at the time of the reset. Be paranoid and force a read of the CSB write pointer from memory. Signed-off-by: Chris Wilson Cc: Mika Kuoppala Reviewed-by: Mika Kuoppala --- drivers/gpu/drm/i915/gt/intel_lrc.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c index 3d83c7e0d9de..61a38a4ccbca 100644 --- a/drivers/gpu/drm/i915/gt/intel_lrc.c +++ b/drivers/gpu/drm/i915/gt/intel_lrc.c @@ -2836,6 +2836,10 @@ static void __execlists_reset(struct intel_engine_cs *engine, bool stalled) struct i915_request *rq; u32 *regs; + mb(); /* paranoia: read the CSB pointers from after the reset */ + clflush(execlists->csb_write); + mb(); + process_csb(engine); /* drain preemption events */ /* Following the reset, we need to reload the CSB read/write pointers */