From patchwork Mon Oct 31 11:54:52 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Gupta, Anshuman" X-Patchwork-Id: 13025680 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 7E246C38A02 for ; Mon, 31 Oct 2022 11:55:12 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 6CF7910E1A9; Mon, 31 Oct 2022 11:55:11 +0000 (UTC) Received: from mga06.intel.com (mga06b.intel.com [134.134.136.31]) by gabe.freedesktop.org (Postfix) with ESMTPS id 797A110E1A8 for ; Mon, 31 Oct 2022 11:55:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1667217306; x=1698753306; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=dlKlUgA5FSjeYBhSTywBPcGaWFao8gJxzrj0wPdMzpE=; b=SSTXzUJXG4O0PnBvFFRyHWX+/pMueX3R0e8CCL+VBxZfuN7xypopGlxu Rzhk1V2Ckz85hJiK+iVqcszcqWzybyl0pNE5fFd9JwTkdtq/gbGN60FNY p7EZxOa+/Irv2Pj3zRYh+r6KaRuWEUZyW7k0E+SztJ5NspSOrPXOrFp/2 sepamwgXkcbiPsMGFUzZwmKx2DcgK9as5+Bp6CW4v8GF4eITvopLtDkfI K4aiWOUg7FLySd6yBr6CQhXeYhb2Mrj3NEc0zzVJwlkli5s8glfsF6VAa tGSRY1lPtvlrmU1YAnIMvAHAs32Q/Wemd2/zxIiJAdKDlf01wN318Q4Sb g==; X-IronPort-AV: E=McAfee;i="6500,9779,10516"; a="370953426" X-IronPort-AV: E=Sophos;i="5.95,227,1661842800"; d="scan'208";a="370953426" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 Oct 2022 04:55:05 -0700 X-IronPort-AV: E=McAfee;i="6500,9779,10516"; a="696985503" X-IronPort-AV: E=Sophos;i="5.95,227,1661842800"; d="scan'208";a="696985503" Received: from anshuma1-desk.iind.intel.com ([10.190.239.112]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 Oct 2022 04:55:03 -0700 From: Anshuman Gupta To: intel-gfx@lists.freedesktop.org Date: Mon, 31 Oct 2022 17:24:52 +0530 Message-Id: <20221031115452.1813981-1-anshuman.gupta@intel.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH] drm/i915/selftest: Fix gt_pm live_gt_clocks test 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: , Cc: rodrigo.vivi@intel.com Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" While reading the engine timestamps there can be uncontrollable concurrent mmio access via other i915 child drivers and by GuC, which may cause mmio latency to read the engine timestamps, Account such latency to calculate time to read engine timestamp. Signed-off-by: Anshuman Gupta --- drivers/gpu/drm/i915/gt/selftest_gt_pm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/gt/selftest_gt_pm.c b/drivers/gpu/drm/i915/gt/selftest_gt_pm.c index be94f863bdef..4f299590ae62 100644 --- a/drivers/gpu/drm/i915/gt/selftest_gt_pm.c +++ b/drivers/gpu/drm/i915/gt/selftest_gt_pm.c @@ -50,8 +50,8 @@ static void measure_clocks(struct intel_engine_cs *engine, udelay(1000); - dt[i] = ktime_sub(ktime_get(), dt[i]); cycles[i] += ENGINE_READ_FW(engine, RING_TIMESTAMP); + dt[i] = ktime_sub(ktime_get(), dt[i]); local_irq_enable(); }