[Intel-gfx] [PATCH] drm/i915/skl: Implement WaBarrierPerformanceFixDisable (again)

[Nick Hoath]

On 03/06/2015 00:02, Widawsky, Benjamin wrote:

Probably should have a line like:
Problem introduced in:
instead of just 'in'

> in
> commit 65ca7514e21adbee25b8175fc909759c735d00ff
> Author: Damien Lespiau <damien.lespiau at intel.com>
> Date:   Mon Feb 9 19:33:22 2015 +0000
>
>      drm/i915/skl: Implement WaBarrierPerformanceFixDisable
>
> The workaround ended up in the chv workarounds. Not sure what the reason or
> history of that is, but it /seems/ wrong. Don't know if this fixes anything

patch doesn't always get it right...

Reviewed-by: Nick Hoath <nicholas.hoath at intel.com>

> since I have many other problems with my platform.
>
> Cc: Damien Lespiau <damien.lespiau at intel.com>
> Cc: Nick Hoath <nicholas.hoath at intel.com>
> Signed-off-by: Ben Widawsky <ben at bwidawsk.net>
> ---
>   drivers/gpu/drm/i915/intel_ringbuffer.c | 14 +++++++-------
>   1 file changed, 7 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
> index d934f85..0fd6033d 100644
> --- a/drivers/gpu/drm/i915/intel_ringbuffer.c
> +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
> @@ -901,13 +901,6 @@ static int chv_init_workarounds(struct intel_engine_cs *ring)
>   			    GEN6_WIZ_HASHING_MASK,
>   			    GEN6_WIZ_HASHING_16x4);
>
> -	if (INTEL_REVID(dev) == SKL_REVID_C0 ||
> -	    INTEL_REVID(dev) == SKL_REVID_D0)
> -		/* WaBarrierPerformanceFixDisable:skl */
> -		WA_SET_BIT_MASKED(HDC_CHICKEN0,
> -				  HDC_FENCE_DEST_SLM_DISABLE |
> -				  HDC_BARRIER_PERFORMANCE_DISABLE);
> -
>   	return 0;
>   }
>
> @@ -972,6 +965,13 @@ static int gen9_init_workarounds(struct intel_engine_cs *ring)
>   		tmp |= HDC_FORCE_CSR_NON_COHERENT_OVR_DISABLE;
>   	WA_SET_BIT_MASKED(HDC_CHICKEN0, tmp);
>
> +	if (INTEL_REVID(dev) == SKL_REVID_C0 ||
> +	    INTEL_REVID(dev) == SKL_REVID_D0)
> +		/* WaBarrierPerformanceFixDisable:skl */
> +		WA_SET_BIT_MASKED(HDC_CHICKEN0,
> +				  HDC_FENCE_DEST_SLM_DISABLE |
> +				  HDC_BARRIER_PERFORMANCE_DISABLE);
> +
>   	return 0;
>   }
>
>