From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Widawsky Subject: [PATCH 21/21] drm/i915/bdw: Limit GTT to 2GB Date: Thu, 7 Nov 2013 21:40:51 -0800 Message-ID: <1383889251-498-21-git-send-email-benjamin.widawsky@intel.com> References: <1383889251-498-1-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 mga09.intel.com (mga09.intel.com [134.134.136.24]) by gabe.freedesktop.org (Postfix) with ESMTP id D3B46FA060 for ; Fri, 8 Nov 2013 00:17:55 -0800 (PST) In-Reply-To: <1383889251-498-1-git-send-email-benjamin.widawsky@intel.com> 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 Because of the way in which we're allocating the pages for the Aliasing PPGTT, we cannot actually successfully alloc enough space for anything greater than 2GB. Instead of a quick hack to fix this, we should defer until we have the real solution in place (allocating much less contiguous space). This wasn't found sooner because we didn't not have any systems supporting more than a 2GB GTT. Signed-off-by: Ben Widawsky --- drivers/gpu/drm/i915/i915_gem_gtt.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c index 5a3cc31..f69bdc7 100644 --- a/drivers/gpu/drm/i915/i915_gem_gtt.c +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c @@ -1239,6 +1239,11 @@ static inline unsigned int gen8_get_total_gtt_size(u16 bdw_gmch_ctl) bdw_gmch_ctl &= BDW_GMCH_GGMS_MASK; if (bdw_gmch_ctl) bdw_gmch_ctl = 1 << bdw_gmch_ctl; + if (bdw_gmch_ctl > 4) { + WARN_ON(!i915_preliminary_hw_support); + return 4<<20; + } + return bdw_gmch_ctl << 20; } -- 1.8.4.2