From patchwork Tue Oct 20 13:49:53 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Zanoni, Paulo R" X-Patchwork-Id: 7447641 Return-Path: X-Original-To: patchwork-intel-gfx@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 7A6BC9F37F for ; Tue, 20 Oct 2015 13:51:01 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 4550D2076E for ; Tue, 20 Oct 2015 13:50:55 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.kernel.org (Postfix) with ESMTP id 49A1920780 for ; Tue, 20 Oct 2015 13:50:51 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E80256EC36; Tue, 20 Oct 2015 06:50:49 -0700 (PDT) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTP id 17A1F6EC2B for ; Tue, 20 Oct 2015 06:50:44 -0700 (PDT) Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga101.jf.intel.com with ESMTP; 20 Oct 2015 06:50:25 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.17,707,1437462000"; d="scan'208";a="798059537" Received: from quanshi-mobl1.amr.corp.intel.com (HELO panetone.amr.corp.intel.com) ([10.254.77.241]) by orsmga001.jf.intel.com with ESMTP; 20 Oct 2015 06:50:25 -0700 From: Paulo Zanoni To: intel-gfx@lists.freedesktop.org Date: Tue, 20 Oct 2015 11:49:53 -0200 Message-Id: <1445349004-16409-8-git-send-email-paulo.r.zanoni@intel.com> X-Mailer: git-send-email 2.6.1 In-Reply-To: <1445349004-16409-1-git-send-email-paulo.r.zanoni@intel.com> References: <1445349004-16409-1-git-send-email-paulo.r.zanoni@intel.com> Subject: [Intel-gfx] [PATCH 07/18] drm/i915: fix the __intel_fbc_update() comments X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.18 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-Spam-Status: No, score=-4.2 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 X-Virus-Scanned: ClamAV using ClamSMTP Don't try to list in comments the cases where we should enable or disable FBC: it varies a lot with the hardware generations and the code should be the documentation. Also notice that there's already a huge gap between the comments and what's in the code. Signed-off-by: Paulo Zanoni --- drivers/gpu/drm/i915/intel_fbc.c | 26 ++------------------------ 1 file changed, 2 insertions(+), 24 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_fbc.c b/drivers/gpu/drm/i915/intel_fbc.c index e856304..5fa4ce4 100644 --- a/drivers/gpu/drm/i915/intel_fbc.c +++ b/drivers/gpu/drm/i915/intel_fbc.c @@ -853,20 +853,8 @@ static bool intel_fbc_hw_tracking_covers_screen(struct intel_crtc *crtc) * __intel_fbc_update - enable/disable FBC as needed, unlocked * @dev_priv: i915 device instance * - * Set up the framebuffer compression hardware at mode set time. We - * enable it if possible: - * - plane A only (on pre-965) - * - no pixel mulitply/line duplication - * - no alpha buffer discard - * - no dual wide - * - framebuffer <= max_hdisplay in width, max_vdisplay in height - * - * We can't assume that any compression will take place (worst case), - * so the compressed buffer has to be the same size as the uncompressed - * one. It also must reside (along with the line length buffer) in - * stolen memory. - * - * We need to enable/disable FBC on a global basis. + * This function completely reevaluates the status of FBC, then enables, + * disables or maintains it on the same state. */ static void __intel_fbc_update(struct drm_i915_private *dev_priv) { @@ -878,7 +866,6 @@ static void __intel_fbc_update(struct drm_i915_private *dev_priv) WARN_ON(!mutex_is_locked(&dev_priv->fbc.lock)); - /* disable framebuffer compression in vGPU */ if (intel_vgpu_active(dev_priv->dev)) i915.enable_fbc = 0; @@ -892,15 +879,6 @@ static void __intel_fbc_update(struct drm_i915_private *dev_priv) goto out_disable; } - /* - * If FBC is already on, we just have to verify that we can - * keep it that way... - * Need to disable if: - * - more than one pipe is active - * - changing FBC params (stride, fence, mode) - * - new fb is too large to fit in compressed buffer - * - going to an unsupported config (interlace, pixel multiply, etc.) - */ drm_crtc = intel_fbc_find_crtc(dev_priv); if (!drm_crtc) { set_no_fbc_reason(dev_priv, "no output");