Re: [PATCH 1/1] drm/i915: Fixing cursor size parameters for wm calculation

[Damien Lespiau <damien.lespiau@intel.com>]

On Tue, Mar 25, 2014 at 03:46:36PM +0530, sagar.a.kamble@intel.com wrote:
> From: Sagar Kamble <sagar.a.kamble@intel.com>
> 
> Cursor size is changed now take care of larger cursor sizes.
> wm calculation was hardcoded to 64 before so changing it.
> 
> Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> Cc: Jani Nikula <jani.nikula@linux.intel.com>
> Cc: Damien Lespiau <damien.lespiau@intel.com>
> Signed-off-by: Sagar Kamble <sagar.a.kamble@intel.com>
> ---
>  drivers/gpu/drm/i915/intel_pm.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> index ad58ce3..2177e3d 100644
> --- a/drivers/gpu/drm/i915/intel_pm.c
> +++ b/drivers/gpu/drm/i915/intel_pm.c
> @@ -2120,7 +2120,7 @@ static void ilk_compute_wm_parameters(struct drm_crtc *crtc,
>  		p->pri.bytes_per_pixel = crtc->fb->bits_per_pixel / 8;
>  		p->cur.bytes_per_pixel = 4;
>  		p->pri.horiz_pixels = intel_crtc->config.pipe_src_w;
> -		p->cur.horiz_pixels = 64;
> +		p->cur.horiz_pixels = dev->mode_config.cursor_width;

Hum? It seems that mode_config.cursor_width is supposed to have the
preferred cursor size so a generic DDX (for instance) can select a size
that can be used. If we declare 256x256, that generic driver will use a
big buffer for the cursor, without any good reason.

A previous patch from you doesn't seem to to do that correctly by always
setting the max size, we're fine with the default 64x64 (I just sent a
patch to address that).

Instead of using the DRM cursor_config value the natural thing to do
would be to use the actual width being used (sent patch).

-- 
Damien