Re: [PATCH v12 02/13] drm/xe/xelp: Quiesce memory traffic before invalidating AuxCCS

[Rodrigo Vivi <rodrigo.vivi@intel.com>]

On Tue, Sep 23, 2025 at 11:07:55AM +0100, Tvrtko Ursulin wrote:
> According to i915 commit
> ad8ebf12217e ("drm/i915/gt: Ensure memory quiesced before invalidation")
> quiescing of the memory traffic is required before invalidating the AuxCCS
> tables.
> 
> Add an extra pipe control flush to achieve that.
> 
> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

> ---
>  drivers/gpu/drm/xe/xe_ring_ops.c       | 10 +++++++++-
>  drivers/gpu/drm/xe/xe_ring_ops_types.h |  2 +-
>  2 files changed, 10 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_ring_ops.c b/drivers/gpu/drm/xe/xe_ring_ops.c
> index 25259b2784bc..af0141c6f809 100644
> --- a/drivers/gpu/drm/xe/xe_ring_ops.c
> +++ b/drivers/gpu/drm/xe/xe_ring_ops.c
> @@ -358,10 +358,18 @@ static void __emit_job_gen12_render_compute(struct xe_sched_job *job,
>  	struct xe_gt *gt = job->q->gt;
>  	struct xe_device *xe = gt_to_xe(gt);
>  	bool lacks_render = !(gt->info.engine_mask & XE_HW_ENGINE_RCS_MASK);
> +	const bool aux_ccs = has_aux_ccs(xe);
>  	u32 mask_flags = 0;
>  
>  	i = emit_copy_timestamp(lrc, dw, i);
>  
> +	/*
> +	 * On AuxCCS platforms the invalidation of the Aux table requires
> +	 * quiescing the memory traffic beforehand.
> +	 */
> +	if (aux_ccs)
> +		i = emit_render_cache_flush(job, dw, i);
> +
>  	dw[i++] = preparser_disable(true);
>  	if (lacks_render)
>  		mask_flags = PIPE_CONTROL_3D_ARCH_FLAGS;
> @@ -372,7 +380,7 @@ static void __emit_job_gen12_render_compute(struct xe_sched_job *job,
>  	i = emit_pipe_invalidate(mask_flags, job->ring_ops_flush_tlb, dw, i);
>  
>  	/* hsdes: 1809175790 */
> -	if (has_aux_ccs(xe))
> +	if (aux_ccs)
>  		i = emit_aux_table_inv(gt, CCS_AUX_INV, dw, i);
>  
>  	dw[i++] = preparser_disable(false);
> diff --git a/drivers/gpu/drm/xe/xe_ring_ops_types.h b/drivers/gpu/drm/xe/xe_ring_ops_types.h
> index d7e3e150a9a5..477dc7defd72 100644
> --- a/drivers/gpu/drm/xe/xe_ring_ops_types.h
> +++ b/drivers/gpu/drm/xe/xe_ring_ops_types.h
> @@ -8,7 +8,7 @@
>  
>  struct xe_sched_job;
>  
> -#define MAX_JOB_SIZE_DW 58
> +#define MAX_JOB_SIZE_DW 70
>  #define MAX_JOB_SIZE_BYTES (MAX_JOB_SIZE_DW * 4)
>  
>  /**
> -- 
> 2.48.0
>