[Intel-gfx] [PATCH 5/6] drm/i915: Extract skl_check_wm_level() and skl_check_nv12_wm_level()

[Lisovskiy, Stanislav]

On Fri, Mar 05, 2021 at 05:36:09PM +0200, Ville Syrjala wrote:
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> Make the code more typo proof by extracting small helpers that
> do the "do we have enough DDB for the WM level?" checks in
> a consistent manner.
> 
> Cc: Stanislav Lisovskiy <stanislav.lisovskiy at intel.com>
> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>

Reviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy at intel.com>

> ---
>  drivers/gpu/drm/i915/intel_pm.c | 58 ++++++++++++++++++++-------------
>  1 file changed, 35 insertions(+), 23 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> index 38a6feced74f..3e26d8b667a1 100644
> --- a/drivers/gpu/drm/i915/intel_pm.c
> +++ b/drivers/gpu/drm/i915/intel_pm.c
> @@ -4782,6 +4782,36 @@ skl_plane_trans_wm(const struct skl_pipe_wm *pipe_wm,
>  	return &wm->trans_wm;
>  }
>  
> +/*
> + * We only disable the watermarks for each plane if
> + * they exceed the ddb allocation of said plane. This
> + * is done so that we don't end up touching cursor
> + * watermarks needlessly when some other plane reduces
> + * our max possible watermark level.
> + *
> + * Bspec has this to say about the PLANE_WM enable bit:
> + * "All the watermarks at this level for all enabled
> + *  planes must be enabled before the level will be used."
> + * So this is actually safe to do.
> + */
> +static void
> +skl_check_wm_level(struct skl_wm_level *wm, u64 total)
> +{
> +	if (wm->min_ddb_alloc > total)
> +		memset(wm, 0, sizeof(*wm));
> +}
> +
> +static void
> +skl_check_nv12_wm_level(struct skl_wm_level *wm, struct skl_wm_level *uv_wm,
> +			u64 total, u64 uv_total)
> +{
> +	if (wm->min_ddb_alloc > total ||
> +	    uv_wm->min_ddb_alloc > uv_total) {
> +		memset(wm, 0, sizeof(*wm));
> +		memset(uv_wm, 0, sizeof(*uv_wm));
> +	}
> +}
> +
>  static int
>  skl_allocate_plane_ddb(struct intel_atomic_state *state,
>  		       struct intel_crtc *crtc)
> @@ -4949,21 +4979,8 @@ skl_allocate_plane_ddb(struct intel_atomic_state *state,
>  			struct skl_plane_wm *wm =
>  				&crtc_state->wm.skl.optimal.planes[plane_id];
>  
> -			/*
> -			 * We only disable the watermarks for each plane if
> -			 * they exceed the ddb allocation of said plane. This
> -			 * is done so that we don't end up touching cursor
> -			 * watermarks needlessly when some other plane reduces
> -			 * our max possible watermark level.
> -			 *
> -			 * Bspec has this to say about the PLANE_WM enable bit:
> -			 * "All the watermarks at this level for all enabled
> -			 *  planes must be enabled before the level will be used."
> -			 * So this is actually safe to do.
> -			 */
> -			if (wm->wm[level].min_ddb_alloc > total[plane_id] ||
> -			    wm->uv_wm[level].min_ddb_alloc > uv_total[plane_id])
> -				memset(&wm->wm[level], 0, sizeof(wm->wm[level]));
> +			skl_check_nv12_wm_level(&wm->wm[level], &wm->uv_wm[level],
> +						total[plane_id], uv_total[plane_id]);
>  
>  			/*
>  			 * Wa_1408961008:icl, ehl
> @@ -4986,14 +5003,9 @@ skl_allocate_plane_ddb(struct intel_atomic_state *state,
>  		struct skl_plane_wm *wm =
>  			&crtc_state->wm.skl.optimal.planes[plane_id];
>  
> -		if (wm->trans_wm.min_ddb_alloc > total[plane_id])
> -			memset(&wm->trans_wm, 0, sizeof(wm->trans_wm));
> -
> -		if (wm->sagv.wm0.min_ddb_alloc > total[plane_id])
> -			memset(&wm->sagv.wm0, 0, sizeof(wm->sagv.wm0));
> -
> -		if (wm->sagv.trans_wm.min_ddb_alloc > total[plane_id])
> -			memset(&wm->sagv.trans_wm, 0, sizeof(wm->sagv.trans_wm));
> +		skl_check_wm_level(&wm->trans_wm, total[plane_id]);
> +		skl_check_wm_level(&wm->sagv.wm0, total[plane_id]);
> +		skl_check_wm_level(&wm->sagv.trans_wm, total[plane_id]);
>  	}
>  
>  	return 0;
> -- 
> 2.26.2
>