[Intel-gfx] [PATCH] drm/i915/gt: Flush before changing register state

[Mika Kuoppala]

Chris Wilson <chris at chris-wilson.co.uk> writes:

> Flush; invalidate; change registers; invalidate; flush.
>
> Will this finally work on every device? Or will Baytrail complain again?
>
> On the positive side, we immediate see the benefit of having hsw-gt1 in
> CU.
CI

Acked-by: Mika Kuoppala <mika.kuoppala at linux.intel.com>

>
> Fixes: ace44e13e577 ("drm/i915/gt: Clear CACHE_MODE prior to clearing residuals")
> Testcase: igt/gem_render_tiled_blits # hsw-gt1
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Mika Kuoppala <mika.kuoppala at linux.intel.com>
> Cc: Akeem G Abodunrin <akeem.g.abodunrin at intel.com>
> ---
>  drivers/gpu/drm/i915/gt/gen7_renderclear.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/drivers/gpu/drm/i915/gt/gen7_renderclear.c b/drivers/gpu/drm/i915/gt/gen7_renderclear.c
> index 8551e6de50e8..e403eb046a43 100644
> --- a/drivers/gpu/drm/i915/gt/gen7_renderclear.c
> +++ b/drivers/gpu/drm/i915/gt/gen7_renderclear.c
> @@ -393,6 +393,7 @@ static void emit_batch(struct i915_vma * const vma,
>  						     desc_count);
>  
>  	/* Reset inherited context registers */
> +	gen7_emit_pipeline_flush(&cmds);
>  	gen7_emit_pipeline_invalidate(&cmds);
>  	batch_add(&cmds, MI_LOAD_REGISTER_IMM(2));
>  	batch_add(&cmds, i915_mmio_reg_offset(CACHE_MODE_0_GEN7));
> -- 
> 2.20.1