[PATCH 6/8] drm/vram-helper: don't use ttm bo->offset v2

[Daniel Vetter]

On Wed, Feb 19, 2020 at 02:53:20PM +0100, Nirmoy Das wrote:
> Calculate GEM VRAM bo's offset within vram-helper without depending on
> bo->offset
> 
> Signed-off-by: Nirmoy Das <nirmoy.das at amd.com>
> ---
>  drivers/gpu/drm/drm_gem_vram_helper.c | 17 ++++++++++++++++-
>  1 file changed, 16 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/drm_gem_vram_helper.c b/drivers/gpu/drm/drm_gem_vram_helper.c
> index 92a11bb42365..3edf5f241c15 100644
> --- a/drivers/gpu/drm/drm_gem_vram_helper.c
> +++ b/drivers/gpu/drm/drm_gem_vram_helper.c
> @@ -198,6 +198,21 @@ u64 drm_gem_vram_mmap_offset(struct drm_gem_vram_object *gbo)
>  }
>  EXPORT_SYMBOL(drm_gem_vram_mmap_offset);
> 
> +/**
> + * drm_gem_vram_pg_offset() - Returns a GEM VRAM object's page offset
> + * @gbo:	the GEM VRAM object
> + *
> + * Returns:
> + * The buffer object's page offset, or
> + * 0 with a warning when memory manager node of the buffer object is NULL
> + * */

We generally don't add full formal kerneldoc for internal functions like
this. It won't get pulled into generated docs and generally just bitrots.
Just informal comment if it's really tricky, but the function name here is
clear enough I think.

So with the comment removed:

Reviewed-by: Daniel Vetter <daniel.vetter at ffwll.ch>

> +static s64 drm_gem_vram_pg_offset(struct drm_gem_vram_object *gbo)
> +{
> +	if (WARN_ON_ONCE(!gbo->bo.mem.mm_node))
> +		return 0;
> +	return gbo->bo.mem.start;
> +}
> +
>  /**
>   * drm_gem_vram_offset() - \
>  	Returns a GEM VRAM object's offset in video memory
> @@ -214,7 +229,7 @@ s64 drm_gem_vram_offset(struct drm_gem_vram_object *gbo)
>  {
>  	if (WARN_ON_ONCE(!gbo->pin_count))
>  		return (s64)-ENODEV;
> -	return gbo->bo.offset;
> +	return drm_gem_vram_pg_offset(gbo) << PAGE_SHIFT;
>  }
>  EXPORT_SYMBOL(drm_gem_vram_offset);
> 
> --
> 2.25.0
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch