[Intel-gfx] [PATCH 09/13] drm/i915/dsb: Introduce intel_dsb_align_tail()

[Manna, Animesh]

> -----Original Message-----
> From: Intel-gfx <intel-gfx-bounces at lists.freedesktop.org> On Behalf Of Ville
> Syrjala
> Sent: Friday, December 16, 2022 6:08 AM
> To: intel-gfx at lists.freedesktop.org
> Subject: [Intel-gfx] [PATCH 09/13] drm/i915/dsb: Introduce
> intel_dsb_align_tail()
> 
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> Move the DSB tail cacheline alignment to a helper. No need to pollute the
> caller with mundane details like this.
> 
> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>

LGTM.
Reviewed-by: Animesh Manna <animesh.manna at intel.com>

> ---
>  drivers/gpu/drm/i915/display/intel_dsb.c | 24 ++++++++++++++++++------
>  1 file changed, 18 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_dsb.c
> b/drivers/gpu/drm/i915/display/intel_dsb.c
> index fa4b808a8134..636c57767f97 100644
> --- a/drivers/gpu/drm/i915/display/intel_dsb.c
> +++ b/drivers/gpu/drm/i915/display/intel_dsb.c
> @@ -187,6 +187,22 @@ void intel_dsb_reg_write(struct intel_dsb *dsb,
>  	}
>  }
> 
> +static u32 intel_dsb_align_tail(struct intel_dsb *dsb) {
> +	u32 aligned_tail, tail;
> +
> +	tail = dsb->free_pos * 4;
> +	aligned_tail = ALIGN(tail, CACHELINE_BYTES);
> +
> +	if (aligned_tail > tail)
> +		memset(&dsb->cmd_buf[dsb->free_pos], 0,
> +		       aligned_tail - tail);
> +
> +	dsb->free_pos = aligned_tail / 4;
> +
> +	return aligned_tail;
> +}
> +
>  /**
>   * intel_dsb_commit() - Trigger workload execution of DSB.
>   * @dsb: DSB context
> @@ -200,14 +216,10 @@ void intel_dsb_commit(struct intel_dsb *dsb)
>  	enum pipe pipe = crtc->pipe;
>  	u32 tail;
> 
> -	if (!(dsb && dsb->free_pos))
> +	tail = intel_dsb_align_tail(dsb);
> +	if (tail == 0)
>  		return;
> 
> -	tail = ALIGN(dsb->free_pos * 4, CACHELINE_BYTES);
> -	if (tail > dsb->free_pos * 4)
> -		memset(&dsb->cmd_buf[dsb->free_pos], 0,
> -		       (tail - dsb->free_pos * 4));
> -
>  	if (is_dsb_busy(dev_priv, pipe, dsb->id)) {
>  		drm_err(&dev_priv->drm, "DSB engine is busy.\n");
>  		goto reset;
> --
> 2.37.4