Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

drm/i915: Set the Stencil Cache eviction policy to non-LRA mode.

Browse source 
Clearing bit 5 of CACHE_MODE_0 is necessary to prevent GPU hangs in
OpenGL programs such as Google MapsGL, Google Earth, and gzdoom when
using separate stencil buffers.  Without it, the GPU tries to use the
LRA eviction policy, which isn't supported.  This was supposed to be off
by default, but seems to be on for many machines.

This cannot be done in gen6_init_clock_gating with most of the other
workaround bits; the render ring needs to exist.  Otherwise, the
register write gets dropped on the floor (one printk will show it
changed, but a second printk immediately following shows the value
reverts to the old one).

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=47535
Cc: stable@vger.kernel.org
Cc: Rob Castle <futuredub@gmail.com>
Cc: Eric Appleman <erappleman@gmail.com>
Cc: aaron667@gmx.net
Cc: Keith Packard <keithp@keithp.com>
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This commit is contained in:
Kenneth Graunke 2012-04-27 12:44:41 -07:00 committed by Dave Airlie
parent 700698e7c3
commit 3a69ddd6f8
2 changed files with 9 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

1
drivers/gpu/drm/i915/i915_reg.h
View file

@ -568,6 +568,7 @@
#define CM0_MASK_SHIFT 16
#define CM0_IZ_OPT_DISABLE (1<<6)
#define CM0_ZR_OPT_DISABLE (1<<5)
#define CM0_STC_EVICT_DISABLE_LRA_SNB (1<<5)
#define CM0_DEPTH_EVICT_DISABLE (1<<4)
#define CM0_COLOR_EVICT_DISABLE (1<<3)
#define CM0_DEPTH_WRITE_DISABLE (1<<1)

8
drivers/gpu/drm/i915/intel_ringbuffer.c
View file

@ -401,6 +401,14 @@ static int init_render_ring(struct intel_ring_buffer *ring)
if (INTEL_INFO(dev)->gen >= 6) {
I915_WRITE(INSTPM,
INSTPM_FORCE_ORDERING << 16 | INSTPM_FORCE_ORDERING);
/* From the Sandybridge PRM, volume 1 part 3, page 24:
* "If this bit is set, STCunit will have LRA as replacement
* policy. [...] This bit must be reset. LRA replacement
* policy is not supported."
*/
I915_WRITE(CACHE_MODE_0,
CM0_STC_EVICT_DISABLE_LRA_SNB << CM0_MASK_SHIFT);
}
return ret;