From patchwork Tue Oct 21 10:47:58 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dheeraj Jamwal X-Patchwork-Id: 5115741 Return-Path: X-Original-To: patchwork-ltsi-dev@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 981E29F349 for ; Tue, 21 Oct 2014 11:21:00 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 944992010F for ; Tue, 21 Oct 2014 11:20:59 +0000 (UTC) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id BBA0B200FE for ; Tue, 21 Oct 2014 11:20:58 +0000 (UTC) Received: from mail.linux-foundation.org (localhost [127.0.0.1]) by mail.linuxfoundation.org (Postfix) with ESMTP id 66692DA7; Tue, 21 Oct 2014 11:02:57 +0000 (UTC) X-Original-To: ltsi-dev@lists.linuxfoundation.org Delivered-To: ltsi-dev@mail.linuxfoundation.org Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id AE4F6B47 for ; Tue, 21 Oct 2014 11:02:55 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by smtp1.linuxfoundation.org (Postfix) with ESMTP id 4496F1FB50 for ; Tue, 21 Oct 2014 11:02:55 +0000 (UTC) Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga102.fm.intel.com with ESMTP; 21 Oct 2014 04:02:51 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.04,761,1406617200"; d="scan'208";a="617794355" Received: from ubuntu-desktop.png.intel.com ([10.221.122.25]) by fmsmga002.fm.intel.com with ESMTP; 21 Oct 2014 04:02:41 -0700 From: Dheeraj Jamwal To: ltsi-dev@lists.linuxfoundation.org Date: Tue, 21 Oct 2014 18:47:58 +0800 Message-Id: <1413889294-31328-279-git-send-email-dheerajx.s.jamwal@intel.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1413889294-31328-1-git-send-email-dheerajx.s.jamwal@intel.com> References: <1413889294-31328-1-git-send-email-dheerajx.s.jamwal@intel.com> X-Spam-Status: No, score=-5.6 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org Subject: [LTSI-dev] [PATCH 0278/1094] drm/i915: put runtime PM only when we actually release force_wake X-BeenThere: ltsi-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: "A list to discuss patches, development, and other things related to the LTSI project" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: ltsi-dev-bounces@lists.linuxfoundation.org Errors-To: ltsi-dev-bounces@lists.linuxfoundation.org X-Virus-Scanned: ClamAV using ClamSMTP From: Paulo Zanoni When we call gen6_gt_force_wake_put we don't actually put force_wake, we just schedule gen6_force_wake_work through mod_delayed_work, and that will eventually release force_wake. The problem is that we call intel_runtime_pm_put directly at gen6_gt_force_wake_put, so most of the times we put our runtime PM reference before the delayed work happens, so we may runtime suspend while force_wake is still supposed to be enabled if the graphics autosuspend_delay_ms is too small. Now the nice thing about the current code is that after it triggers the delayed work function it gets a refcount, and it only triggers the delayed work function if refcount is zero. This guarantees that when we schedule the funciton, it will run before we try to schedule it again, which simplifies the problem and allows for the current solution to work properly (hopefully!). v2: - Keep the VLV refcounts balanced (Jesse) Signed-off-by: Paulo Zanoni Reviewed-by: Jesse Barnes Signed-off-by: Daniel Vetter (cherry picked from commit 6d88064edcfc5e5893371f7c06b9f3078dc1edf6) Signed-off-by: Dheeraj Jamwal --- drivers/gpu/drm/i915/intel_uncore.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c index e5b59ac..4c39e24 100644 --- a/drivers/gpu/drm/i915/intel_uncore.c +++ b/drivers/gpu/drm/i915/intel_uncore.c @@ -298,6 +298,8 @@ static void gen6_force_wake_timer(unsigned long arg) if (--dev_priv->uncore.forcewake_count == 0) dev_priv->uncore.funcs.force_wake_put(dev_priv, FORCEWAKE_ALL); spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags); + + intel_runtime_pm_put(dev_priv); } static void intel_uncore_forcewake_reset(struct drm_device *dev) @@ -392,24 +394,30 @@ void gen6_gt_force_wake_get(struct drm_i915_private *dev_priv, int fw_engine) void gen6_gt_force_wake_put(struct drm_i915_private *dev_priv, int fw_engine) { unsigned long irqflags; + bool delayed = false; if (!dev_priv->uncore.funcs.force_wake_put) return; /* Redirect to VLV specific routine */ - if (IS_VALLEYVIEW(dev_priv->dev)) - return vlv_force_wake_put(dev_priv, fw_engine); + if (IS_VALLEYVIEW(dev_priv->dev)) { + vlv_force_wake_put(dev_priv, fw_engine); + goto out; + } spin_lock_irqsave(&dev_priv->uncore.lock, irqflags); if (--dev_priv->uncore.forcewake_count == 0) { dev_priv->uncore.forcewake_count++; + delayed = true; mod_timer_pinned(&dev_priv->uncore.force_wake_timer, jiffies + 1); } spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags); - intel_runtime_pm_put(dev_priv); +out: + if (!delayed) + intel_runtime_pm_put(dev_priv); } /* We give fast paths for the really cool registers */