Re: [Intel-gfx] [PATCH] drm/i915: Apply Wa_14011264657:gen11+

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Tue, Jun 16, 2020 at 09:34:06AM -0700, Matt Atwood wrote:
> Add minimum width to planes, variable with specific formats, for gen11+.
> 
> Signed-off-by: Matt Atwood <matthew.s.atwood@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_display.c | 55 +++++++++++++++++---
>  1 file changed, 47 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
> index 7457813ef273..d4fdad6cb3b1 100644
> --- a/drivers/gpu/drm/i915/display/intel_display.c
> +++ b/drivers/gpu/drm/i915/display/intel_display.c
> @@ -3760,6 +3760,45 @@ static int glk_max_plane_width(const struct drm_framebuffer *fb,
>  	}
>  }
>  
> +static int icl_min_plane_width(struct drm_i915_private *dev_priv,
> +				 const struct drm_framebuffer *fb)
> +{
> +	/* Wa_14011264657, Wa_14011050563 */
> +	switch (fb->format->format) {
> +	case DRM_FORMAT_C8:
> +		return 18;
> +	case DRM_FORMAT_RGB565:
> +		return 10;
> +	case DRM_FORMAT_XRGB8888:
> +	case DRM_FORMAT_XBGR8888:
> +	case DRM_FORMAT_ARGB8888:
> +	case DRM_FORMAT_ABGR8888:
> +	case DRM_FORMAT_XRGB2101010:
> +	case DRM_FORMAT_XBGR2101010:
> +	case DRM_FORMAT_ARGB2101010:
> +	case DRM_FORMAT_ABGR2101010:
> +	case DRM_FORMAT_XVYU2101010:
> +	case DRM_FORMAT_Y212:
> +	case DRM_FORMAT_Y216:
> +		return 6;
> +	case DRM_FORMAT_NV12:
> +		return 20;
> +	case DRM_FORMAT_P010:
> +	case DRM_FORMAT_P012:
> +	case DRM_FORMAT_P016:
> +		return 12;
> +	case DRM_FORMAT_XRGB16161616F:
> +	case DRM_FORMAT_XBGR16161616F:
> +	case DRM_FORMAT_ARGB16161616F:
> +	case DRM_FORMAT_ABGR16161616F:
> +	case DRM_FORMAT_XVYU12_16161616:
> +	case DRM_FORMAT_XVYU16161616:
> +		return 4;
> +	default:
> +		return 1;
> +	}

if (semiplanar) {
	switch (cpp[0]) {
	case 1:
		return 20;
	case 2:
		return 12;
	}
} else {
	switch (cpp[0]) {
	case 1:
		return 18;
	case 2:
		return 10;
	case 4:
		return 6;
	case 8:
		return 4;
	}
}

Actually if we fully reverse engineer this we are left with just:
if (semiplanar)
	return 16/cpp[0] + 4;
else
	return 16/cpp[0] + 2;

I'd much prefer calculating this since then it's fully divorced from
defining new pixel formats. Can we get a confirmation from the hw
folks if that is in fact the formula (or if there's a different formula
how they came up with these magic numbers)?

> +}
> +
>  static int icl_max_plane_width(const struct drm_framebuffer *fb,
>  			       int color_plane,
>  			       unsigned int rotation)
> @@ -3831,15 +3870,15 @@ static int skl_check_main_surface(struct intel_plane_state *plane_state)
>  	int y = plane_state->uapi.src.y1 >> 16;
>  	int w = drm_rect_width(&plane_state->uapi.src) >> 16;
>  	int h = drm_rect_height(&plane_state->uapi.src) >> 16;
> -	int max_width;
> -	int max_height;
> -	u32 alignment;
> -	u32 offset;
> +	int max_width, min_width = 1, max_height;
> +	u32 alignment, offset;
>  	int aux_plane = intel_main_to_aux_plane(fb, 0);
>  	u32 aux_offset = plane_state->color_plane[aux_plane].offset;
>  
> -	if (INTEL_GEN(dev_priv) >= 11)
> +	if (INTEL_GEN(dev_priv) >= 11) {
>  		max_width = icl_max_plane_width(fb, 0, rotation);
> +		min_width = icl_min_plane_width(dev_priv, fb);
> +	}
>  	else if (INTEL_GEN(dev_priv) >= 10 || IS_GEMINILAKE(dev_priv))

Missing curly braces on all the branches. Feels like dejavu...

I'd also do the min_width=1 assignment in each branch to make it
clear what's what.

>  		max_width = glk_max_plane_width(fb, 0, rotation);
>  	else
> @@ -3850,10 +3889,10 @@ static int skl_check_main_surface(struct intel_plane_state *plane_state)
>  	else
>  		max_height = skl_max_plane_height();
>  
> -	if (w > max_width || h > max_height) {
> +	if (w > max_width || w < min_width || h > max_height) {
>  		drm_dbg_kms(&dev_priv->drm,
> -			    "requested Y/RGB source size %dx%d too big (limit %dx%d)\n",
> -			    w, h, max_width, max_height);
> +			    "requested Y/RGB source size %dx%d outside limits (min: %dx1 max: %dx%d)\n",
> +			    w, h, min_width, max_width, max_height);
>  		return -EINVAL;
>  	}
>  
> -- 
> 2.21.3
> 
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/intel-gfx

-- 
Ville Syrjälä
Intel
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx