[Intel-gfx] [PATCH v3 3/3] drm/i915: use REG_FIELD_PREP() to define register bitfield values

[Ville Syrjälä]

On Wed, Feb 27, 2019 at 07:02:38PM +0200, Jani Nikula wrote:
> Slightly verbose, but does away with hand rolled shifts. Ties the field
> values with the mask defining the field.
> 
> Unfortunately we have to make a local copy of FIELD_PREP() to evaluate
> to a integer constant expression. But with this, we can ensure the mask
> is non-zero, power of 2, fits u32, and the value fits the mask (when the
> value is a constant expression).

I might like a debug knob to make that into a runtime check for
non-const expressions. But that can be considered later.

-- 
Ville Syrjälä
Intel