From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Widawsky Subject: [PATCH 1/2] drm/i915/bdw: Use scratch page table for GEN8 PPGTT Date: Sat, 8 Mar 2014 11:58:16 -0800 Message-ID: <1394308697-3683-1-git-send-email-benjamin.widawsky@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTP id 8AD48FA81B for ; Sat, 8 Mar 2014 11:58:22 -0800 (PST) List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces@lists.freedesktop.org Errors-To: intel-gfx-bounces@lists.freedesktop.org To: Intel GFX Cc: Ben Widawsky , Ben Widawsky List-Id: intel-gfx@lists.freedesktop.org I'm not clear if the hardware is still subject to the same prefetching issues that made us use a scratch page in the first place. In either case, we're using garbage with the current code (we will end up using offset 0). This may be the cause of our current gem_cpu_reloc regression with PPGTT. I cannot test it at the moment. Signed-off-by: Ben Widawsky --- drivers/gpu/drm/i915/i915_gem_gtt.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c index 5427d6d..0f39090 100644 --- a/drivers/gpu/drm/i915/i915_gem_gtt.c +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c @@ -1169,7 +1169,6 @@ static int gen6_ppgtt_init(struct i915_hw_ppgtt *ppgtt) ppgtt->base.clear_range = gen6_ppgtt_clear_range; ppgtt->base.insert_entries = gen6_ppgtt_insert_entries; ppgtt->base.cleanup = gen6_ppgtt_cleanup; - ppgtt->base.scratch = dev_priv->gtt.base.scratch; ppgtt->base.start = 0; ppgtt->base.total = GEN6_PPGTT_PD_ENTRIES * I915_PPGTT_PT_ENTRIES * PAGE_SIZE; ppgtt->debug_dump = gen6_dump_ppgtt; @@ -1192,6 +1191,7 @@ int i915_gem_init_ppgtt(struct drm_device *dev, struct i915_hw_ppgtt *ppgtt) int ret = 0; ppgtt->base.dev = dev; + ppgtt->base.scratch = dev_priv->gtt.base.scratch; if (INTEL_INFO(dev)->gen < 8) ret = gen6_ppgtt_init(ppgtt); -- 1.9.0