This adds support for GENMASK_U128() and some corresponding tests as well.
GENMASK_U128() generated 128 bit masks will be required later on the arm64
platform for enabling FEAT_SYSREG128 and FEAT_D128 features.

Question:

Proposed GENMASK_U128() depends on __int128 data type being supported in
the compiler. Just wondering if that requires some compiler version #ifdefs
or something similar ?

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yury Norov <yury.norov@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Arnd Bergmann <arnd@arndb.de>>
Cc: linux-kernel@vger.kernel.org
Cc: linux-arch@vger.kernel.org

Anshuman Khandual (2):
  uapi: Define GENMASK_U128
  lib/test_bits.c: Add tests for GENMASK_U128()

 include/linux/bits.h                   |  2 ++
 include/uapi/asm-generic/bitsperlong.h |  4 ++++
 include/uapi/linux/bits.h              |  4 ++++
 include/uapi/linux/const.h             |  3 +++
 lib/test_bits.c                        | 21 +++++++++++++++++++++
 5 files changed, 34 insertions(+)

-- 
2.30.2

Hi Anshuman,

On Wed, 24 Jul 2024 at 12:31, Anshuman Khandual
<anshuman.khandual@arm.com> wrote:
>
> This adds support for GENMASK_U128() and some corresponding tests as well.
> GENMASK_U128() generated 128 bit masks will be required later on the arm64
> platform for enabling FEAT_SYSREG128 and FEAT_D128 features.
>
> Question:
>
> Proposed GENMASK_U128() depends on __int128 data type being supported in
> the compiler. Just wondering if that requires some compiler version #ifdefs
> or something similar ?
>

CONFIG_ARCH_SUPPORTS_INT128 comes to mind