[Intel-gfx] [PATCH 5/5] drm/i915: Implement more Broadwell workarounds.

[Ben Widawsky]

On Mon, Jan 27, 2014 at 02:20:18PM -0800, Kenneth Graunke wrote:
> These should only be necessary on pre-production hardware.
> 
> Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
> ---
>  drivers/gpu/drm/i915/i915_reg.h |  1 +
>  drivers/gpu/drm/i915/intel_pm.c | 12 ++++++++++++
>  2 files changed, 13 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> index 418e055..3ad5483 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -5008,6 +5008,7 @@
>  #define   GEN7_PSD_SINGLE_PORT_DISPATCH_ENABLE	(1<<3)
>  
>  #define GEN8_ROW_CHICKEN		0xe4f0
> +#define   INSTRUCTION_SHOOTDOWN_DISABLE	(1<<9)
>  #define   PARTIAL_INSTRUCTION_SHOOTDOWN_DISABLE	(1<<8)
>  #define   STALL_DOP_GATING_DISABLE	(1<<5)
>  
> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> index 801d439..3cec13f 100644
> --- a/drivers/gpu/drm/i915/intel_pm.c
> +++ b/drivers/gpu/drm/i915/intel_pm.c
> @@ -4717,6 +4717,18 @@ static void gen8_init_clock_gating(struct drm_device *dev)
>  	I915_WRITE(GEN8_ROW_CHICKEN,
>  	           _MASKED_BIT_ENABLE(PARTIAL_INSTRUCTION_SHOOTDOWN_DISABLE));
>  
> +	/* WaDisableInstructionShootdown:bdw - pre-production only */
> +	I915_WRITE(GEN8_ROW_CHICKEN,
> +		   _MASKED_BIT_ENABLE(INSTRUCTION_SHOOTDOWN_DISABLE));
> +
> +	/* WaDisableThreadStallDopClockGating:bdw - pre-production only */
> +	I915_WRITE(GEN8_ROW_CHICKEN,
> +		   _MASKED_BIT_ENABLE(STALL_DOP_GATING_DISABLE));

bspec leads me to believe this one is not pre-production only.

> +
> +	/* WaDisableRowChickenDopClockGating:bdw - pre-production only */
> +	I915_WRITE(GEN7_ROW_CHICKEN2,
> +		   _MASKED_BIT_ENABLE(DOP_CLOCK_GATING_DISABLE));
> +
>  	/*
>  	 * This GEN8_CENTROID_PIXEL_OPT_DIS W/A is only needed for
>  	 * pre-production hardware

Other than the two minor nitpicks, lgtm in patch 1, and here:
Reviewed-by: Ben Widawsky <ben at bwidawsk.net>

-- 
Ben Widawsky, Intel Open Source Technology Center