From patchwork Mon Jun 30 16:53:35 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Rodrigo Vivi X-Patchwork-Id: 4455471 Return-Path: X-Original-To: patchwork-intel-gfx@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id D93E1BEEAA for ; Mon, 30 Jun 2014 23:52:31 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 95BE020379 for ; Mon, 30 Jun 2014 23:52:30 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.kernel.org (Postfix) with ESMTP id 7D1FA202F0 for ; Mon, 30 Jun 2014 23:52:29 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 828626E270; Mon, 30 Jun 2014 16:52:28 -0700 (PDT) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by gabe.freedesktop.org (Postfix) with ESMTP id 0E8B06E270 for ; Mon, 30 Jun 2014 16:52:27 -0700 (PDT) Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga102.jf.intel.com with ESMTP; 30 Jun 2014 16:46:59 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.01,578,1400050800"; d="scan'208";a="566306949" Received: from di-604.jf.intel.com (HELO rdvivi-hillsboro.jf.intel.com) ([10.7.201.28]) by orsmga002.jf.intel.com with ESMTP; 30 Jun 2014 16:52:26 -0700 From: Rodrigo Vivi To: intel-gfx@lists.freedesktop.org Date: Mon, 30 Jun 2014 09:53:35 -0700 Message-Id: <1404147224-2978-1-git-send-email-rodrigo.vivi@intel.com> X-Mailer: git-send-email 1.9.3 MIME-Version: 1.0 Cc: Ben Widawsky , Rodrigo Vivi Subject: [Intel-gfx] [PATCH 01/10] drm/i915: Make semaphore updates more precise X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.15 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" X-Spam-Status: No, score=-2.7 required=5.0 tests=BAYES_00, DATE_IN_PAST_06_12, RCVD_IN_DNSWL_MED, T_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 From: Ben Widawsky With the ring mask we now have an easy way to know the number of rings in the system, and therefore can accurately predict the number of dwords to emit for semaphore signalling. This was not possible (easily) previously. There should be no functional impact, simply fewer instructions emitted. While we're here, simply do the round up to 2 instead of the fancier rounding we did before, which rounding up per mbox, ie 4. This also allows us to drop the unnecessary MI_NOOP, so not really 4, 3. v2: Use 3 dwords instead of 4 (Ville) Do the proper calculation to get the number of dwords to emit (Ville) Conditionally set .sync_to when semaphores are enabled (Ville) v3: Rebased on VCS2 Replace hweight_long with hweight32 (Ville) v4: Pull out the accidentally squashed hunk from the next patch after rebase (Daniel). v5: Fix conflict after rebase (Rodrigo) Reviewed-by: Rodrigo Vivi Reviewed-by: Ville Syrjälä (v1) Signed-off-by: Ben Widawsky Signed-off-by: Rodrigo Vivi --- drivers/gpu/drm/i915/intel_ringbuffer.c | 27 +++++++++------------------ 1 file changed, 9 insertions(+), 18 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index 2faef26..5c20536 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -679,23 +679,16 @@ static int gen6_signal(struct intel_engine_cs *signaller, struct drm_device *dev = signaller->dev; struct drm_i915_private *dev_priv = dev->dev_private; struct intel_engine_cs *useless; - int i, ret; + int i, ret, num_rings; - /* NB: In order to be able to do semaphore MBOX updates for varying - * number of rings, it's easiest if we round up each individual update - * to a multiple of 2 (since ring updates must always be a multiple of - * 2) even though the actual update only requires 3 dwords. - */ -#define MBOX_UPDATE_DWORDS 4 - if (i915_semaphore_is_enabled(dev)) - num_dwords += ((I915_NUM_RINGS-1) * MBOX_UPDATE_DWORDS); - else - return intel_ring_begin(signaller, num_dwords); +#define MBOX_UPDATE_DWORDS 3 + num_rings = hweight32(INTEL_INFO(dev)->ring_mask); + num_dwords += round_up((num_rings-1) * MBOX_UPDATE_DWORDS, 2); +#undef MBOX_UPDATE_DWORDS ret = intel_ring_begin(signaller, num_dwords); if (ret) return ret; -#undef MBOX_UPDATE_DWORDS for_each_ring(useless, dev_priv, i) { u32 mbox_reg = signaller->semaphore.mbox.signal[i]; @@ -703,15 +696,13 @@ static int gen6_signal(struct intel_engine_cs *signaller, intel_ring_emit(signaller, MI_LOAD_REGISTER_IMM(1)); intel_ring_emit(signaller, mbox_reg); intel_ring_emit(signaller, signaller->outstanding_lazy_seqno); - intel_ring_emit(signaller, MI_NOOP); - } else { - intel_ring_emit(signaller, MI_NOOP); - intel_ring_emit(signaller, MI_NOOP); - intel_ring_emit(signaller, MI_NOOP); - intel_ring_emit(signaller, MI_NOOP); } } + /* If num_dwords was rounded, make sure the tail pointer is correct */ + if (num_rings % 2 == 0) + intel_ring_emit(signaller, MI_NOOP); + return 0; }