drm/i915: don't pwrite tiled objects through the gtt

... we will botch up the bit17 swizzling. Furthermore tiled pwrite is
a (now) unused slowpath, so no one really cares.

This fixes the last swizzling issues I have with i-g-t on my bit17
swizzling i915G. No regression, it's been broken since the dawn of
gem, but it's nice for regression tracking when really _all_ i-g-t
tests work.

Actually this is not true, Chris Wilson noticed while reviewing this
patch that the commit

commit d9e86c0ee60f323e890484628f351bf50fa9a15d
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Wed Nov 10 16:40:20 2010 +0000

    drm/i915: Pipelined fencing [infrastructure]

contained a functional change that broke things.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 71934dd0ee43..9415c07b6285 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -876,6 +876,7 @@ i915_gem_pwrite_ioctl(struct drm_device *dev, void *data,
 
         if (obj->gtt_space &&
             obj->cache_level == I915_CACHE_NONE &&
+            obj->tiling_mode == I915_TILING_NONE &&
             obj->map_and_fenceable &&
             obj->base.write_domain != I915_GEM_DOMAIN_CPU) {
                 ret = i915_gem_gtt_pwrite_fast(dev, obj, args, file);