[PATCH 13/20] drm/i915/fbc: Extract intel_fbc_cfb_cpp()

[Shankar, Uma]

> -----Original Message-----
> From: Intel-xe <intel-xe-bounces at lists.freedesktop.org> On Behalf Of Ville Syrjala
> Sent: Friday, July 5, 2024 8:23 PM
> To: intel-gfx at lists.freedesktop.org
> Cc: intel-xe at lists.freedesktop.org
> Subject: [PATCH 13/20] drm/i915/fbc: Extract intel_fbc_cfb_cpp()
> 
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> Extract a helper to determine the CFB bytes per pixel value.
> Currently this is always 4, but that could change in the future.

Looks Good to me.
Reviewed-by: Uma Shankar <uma.shankar at intel.com>

> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_fbc.c | 18 ++++++++++++------
>  1 file changed, 12 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c
> b/drivers/gpu/drm/i915/display/intel_fbc.c
> index 293e1a3b9a9d..a0e539bc80f1 100644
> --- a/drivers/gpu/drm/i915/display/intel_fbc.c
> +++ b/drivers/gpu/drm/i915/display/intel_fbc.c
> @@ -140,20 +140,24 @@ static unsigned int intel_fbc_plane_stride(const struct
> intel_plane_state *plane
>  	return stride;
>  }
> 
> +static unsigned int intel_fbc_cfb_cpp(void) {
> +	return 4; /* FBC always 4 bytes per pixel */ }
> +
>  /* plane stride based cfb stride in bytes, assuming 1:1 compression limit */  static
> unsigned int intel_fbc_plane_cfb_stride(const struct intel_plane_state
> *plane_state)  {
> -	unsigned int cpp = 4; /* FBC always 4 bytes per pixel */
> +	unsigned int cpp = intel_fbc_cfb_cpp();
> 
>  	return intel_fbc_plane_stride(plane_state) * cpp;  }
> 
>  /* minimum acceptable cfb stride in bytes, assuming 1:1 compression limit */
> static unsigned int skl_fbc_min_cfb_stride(struct intel_display *display,
> -					   unsigned int width)
> +					   unsigned int cpp, unsigned int width)
>  {
>  	unsigned int limit = 4; /* 1:4 compression limit is the worst case */
> -	unsigned int cpp = 4; /* FBC always 4 bytes per pixel */
>  	unsigned int height = 4; /* FBC segment is 4 lines */
>  	unsigned int stride;
> 
> @@ -179,7 +183,8 @@ static unsigned int skl_fbc_min_cfb_stride(struct
> intel_display *display,
> 
>  /* properly aligned cfb stride in bytes, assuming 1:1 compression limit */  static
> unsigned int _intel_fbc_cfb_stride(struct intel_display *display,
> -					  unsigned int width, unsigned int stride)
> +					  unsigned int cpp, unsigned int width,
> +					  unsigned int stride)
>  {
>  	/*
>  	 * At least some of the platforms require each 4 line segment to @@ -
> 187,7 +192,7 @@ static unsigned int _intel_fbc_cfb_stride(struct intel_display
> *display,
>  	 * that regardless of the compression limit we choose later.
>  	 */
>  	if (DISPLAY_VER(display) >= 9)
> -		return max(ALIGN(stride, 512), skl_fbc_min_cfb_stride(display,
> width));
> +		return max(ALIGN(stride, 512), skl_fbc_min_cfb_stride(display,
> cpp,
> +width));
>  	else
>  		return stride;
>  }
> @@ -197,8 +202,9 @@ static unsigned int intel_fbc_cfb_stride(const struct
> intel_plane_state *plane_s
>  	struct intel_display *display = to_intel_display(plane_state->uapi.plane-
> >dev);
>  	unsigned int stride = intel_fbc_plane_cfb_stride(plane_state);
>  	unsigned int width = drm_rect_width(&plane_state->uapi.src) >> 16;
> +	unsigned int cpp = intel_fbc_cfb_cpp();
> 
> -	return _intel_fbc_cfb_stride(display, width, stride);
> +	return _intel_fbc_cfb_stride(display, cpp, width, stride);
>  }
> 
>  /*
> --
> 2.44.2