[PATCH] Revert "drm/i915: GFX_MODE Flush TLB Invalidate Mode must be '1' for scanline waits"

[Luis Henriques]

On Mon, Apr 22, 2013 at 04:23:17PM -0500, Steve Conklin wrote:
> This reverts commit 30ae292ec68402c773ddc8c80f83f7cd84289a39.
> 
> This has been shown to cause GPU hangs
> ---
>  drivers/gpu/drm/i915/intel_ringbuffer.c |    5 -----
>  1 file changed, 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
> index c3654ff..fbaa785 100644
> --- a/drivers/gpu/drm/i915/intel_ringbuffer.c
> +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
> @@ -422,11 +422,6 @@ static int init_render_ring(struct intel_ring_buffer *ring)
>  	if (INTEL_INFO(dev)->gen >= 6)
>  		I915_WRITE(MI_MODE, GFX_MODE_ENABLE(ASYNC_FLIP_PERF_DISABLE));
>  
> -	/* Required for the hardware to program scanline values for waiting */
> -	if (INTEL_INFO(dev)->gen == 6)
> -		I915_WRITE(GFX_MODE,
> -			   GFX_MODE_ENABLE(GFX_TLB_INVALIDATE_ALWAYS));
> -
>  	if (IS_GEN7(dev))
>  		I915_WRITE(GFX_MODE_GEN7,
>  			   GFX_MODE_DISABLE(GFX_TLB_INVALIDATE_ALWAYS) |
> -- 
> 1.7.9.5
> 
> 
> -- 
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Comment 99 in bug #1167114 refers to a debian bug that seems to be a
duplicate.  And the solution was commit
054430e773c9a1e26f38e30156eff02dedfffc17 (fbcon: fix locking harder).
Maybe its worth trying a kernel with this fix.

(This commit is already in 3.5.y, so I should have already identified
it as a possible fix for these bugs... My bad, I've queued it without
taking a look at the full context.)

Cheers,
--
Luis