From patchwork Tue Jan 19 11:08:00 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 12029679 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6218EC433E0 for ; Tue, 19 Jan 2021 11:08:12 +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 E854720760 for ; Tue, 19 Jan 2021 11:08:11 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E854720760 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 047C46E841; Tue, 19 Jan 2021 11:08:10 +0000 (UTC) Received: from fireflyinternet.com (unknown [77.68.26.236]) by gabe.freedesktop.org (Postfix) with ESMTPS id DA1D56E841 for ; Tue, 19 Jan 2021 11:08:07 +0000 (UTC) X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Received: from build.alporthouse.com (unverified [78.156.65.138]) by fireflyinternet.com (Firefly Internet (M1)) with ESMTP id 23637622-1500050 for ; Tue, 19 Jan 2021 11:08:03 +0000 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Tue, 19 Jan 2021 11:08:00 +0000 Message-Id: <20210119110802.22228-4-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20210119110802.22228-1-chris@chris-wilson.co.uk> References: <20210119110802.22228-1-chris@chris-wilson.co.uk> MIME-Version: 1.0 Subject: [Intel-gfx] [CI 4/6] drm/i915/gt: Disable the ring before resetting HEAD/TAIL X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 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" During the reset of ring submission, we first stop the engine by clearing the HEAD/TAIL and marking the ring as disabled. However, it would be safer to disable the ring (after emptying) before resetting the HEAD/TAIL. Suggested-by: Mika Kuoppala Signed-off-by: Chris Wilson Cc: Mika Kuoppala Reviewed-by: Mika Kuoppala --- drivers/gpu/drm/i915/gt/intel_ring_submission.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_ring_submission.c b/drivers/gpu/drm/i915/gt/intel_ring_submission.c index 44159595d909..8a5314b97b04 100644 --- a/drivers/gpu/drm/i915/gt/intel_ring_submission.c +++ b/drivers/gpu/drm/i915/gt/intel_ring_submission.c @@ -301,13 +301,17 @@ static void xcs_sanitize(struct intel_engine_cs *engine) static bool stop_ring(struct intel_engine_cs *engine) { + /* Empty the ring by skipping to the end */ ENGINE_WRITE_FW(engine, RING_HEAD, ENGINE_READ_FW(engine, RING_TAIL)); - - ENGINE_WRITE_FW(engine, RING_HEAD, 0); - ENGINE_WRITE_FW(engine, RING_TAIL, 0); + ENGINE_POSTING_READ(engine, RING_HEAD); /* The ring must be empty before it is disabled */ ENGINE_WRITE_FW(engine, RING_CTL, 0); + ENGINE_POSTING_READ(engine, RING_CTL); + + /* Then reset the disabled ring */ + ENGINE_WRITE_FW(engine, RING_HEAD, 0); + ENGINE_WRITE_FW(engine, RING_TAIL, 0); return (ENGINE_READ_FW(engine, RING_HEAD) & HEAD_ADDR) == 0; }