[Intel-gfx] [RFC 0/4] drm/i915/registers: use standard bits.h and bitfield.h macros

[Michal Wajdeczko]

On Thu, 27 Sep 2018 11:40:19 +0200, Jani Nikula <jani.nikula at intel.com>  
wrote:

> This is an RFC to get input on how people feel about moving towards
> using <linux/bits.h> and <linux/bitfield.h> macros for register field
> definitions and manipulation:
>
> * BIT()
> * GENMASK()

BIT/GENMASK macros assumes 'unsigned long' type (64b) while our registers
(and some of our temporary variables) are 'unsigned int' (32b).

It was reported [1] that use of plain BIT(0) may cause compilation issues.

Michal

[1]  
https://lists.freedesktop.org/archives/intel-gfx/2018-September/176704.html

> * FIELD_GET()
> * FIELD_PREP()