[Jaunty SRU] LP#349992 Allow to disable GEM on i915 chipset

[Ike Panhc]

> Description
SRU justification:

Impact: Allow to disable GEM on i915 chipset

Fix: Allow to disable GEM on i915 chipset with module parameter

Note:
We could have a proper fix by commit 280b713b5b0fd84cf2469098aee88acbb5de859c
from upstream, but it is a huge commit, the simple one is to allow driver to
disable gem when loaded.


> Request-pull
The following changes since commit 905e2094d74d7afa9f8ca9afcca20ceb67af6ad1:
  Tim Gardner (1):
        UBUNTU: [Config] Updated comments on debug package generation.

are available in the git repository at:

  git://kernel.ubuntu.com/ikepanhc/ike-jaunty.git lp#349992

Ike Panhc (1):
      UBUNTU: SAUCE: Allow to disable GEM on i915

 drivers/gpu/drm/i915/i915_dma.c |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)


> Patch
>From 07d4e3316ca5d8f050959189e6f1ebc76f472eea Mon Sep 17 00:00:00 2001
From: Ike Panhc <ike.pan at canonical.com>
Date: Wed, 6 May 2009 20:51:45 +0800
Subject: [PATCH] UBUNTU: SAUCE: Allow to disable GEM on i915

OriginalAuthor: Vasily Khoruzhick <anarsoul at gmail.com>
OriginalLocation: http://bugs.freedesktop.org/show_bug.cgi?id=16835
Bug: #349992
BugLink: https://bugs.launchpad.net/ubuntu/+bug/349992

Allow to disable GEM on i915 drivers for improvement 3D performance.

Please drop this patch if the following commit is pulled from upstream.
  commit 280b713b5b0fd84cf2469098aee88acbb5de859c
  Author: Eric Anholt <eric at anholt.net>
  drm/i915: Allow tiling of objects with bit 17 swizzling by the CPU.

Signed-off-by: Ike Panhc <ike.pan at canonical.com>
---
 drivers/gpu/drm/i915/i915_dma.c |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index c6d5528..020969d 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -31,6 +31,9 @@
 #include "i915_drm.h"
 #include "i915_drv.h"
 
+static int gem_enable = 1;
+module_param(gem_enable, int, 0400);
+
 /* Really want an OS-independent resettable timer.  Would like to have
  * this loop run for (eg) 3 sec, but have the timer reset every time
  * the head pointer changes, so that EBUSY only happens if the ring
@@ -835,7 +838,7 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
 	dev_priv->has_gem = 0;
 #else
 	/* enable GEM by default */
-	dev_priv->has_gem = 1;
+	dev_priv->has_gem = gem_enable;
 #endif
 
 	dev->driver->get_vblank_counter = i915_get_vblank_counter;
-- 
1.5.6.3