mirror of
git://git.yoctoproject.org/linux-yocto.git
synced 2025-10-23 07:23:12 +02:00
947697c6f0
This adds GENMASK_U128() and __GENMASK_U128() macros using __BITS_PER_U128 and __int128 data types. These macros will be used in providing support for generating 128 bit masks. The macros wouldn't work in all assembler flavors for reasons described in the comments on top of declarations. Enforce it for more by adding !__ASSEMBLY__ guard. 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 Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Yury Norov <yury.norov@gmail.com>
54 lines
1.6 KiB
C
54 lines
1.6 KiB
C
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
|
|
/* const.h: Macros for dealing with constants. */
|
|
|
|
#ifndef _UAPI_LINUX_CONST_H
|
|
#define _UAPI_LINUX_CONST_H
|
|
|
|
/* Some constant macros are used in both assembler and
|
|
* C code. Therefore we cannot annotate them always with
|
|
* 'UL' and other type specifiers unilaterally. We
|
|
* use the following macros to deal with this.
|
|
*
|
|
* Similarly, _AT() will cast an expression with a type in C, but
|
|
* leave it unchanged in asm.
|
|
*/
|
|
|
|
#ifdef __ASSEMBLY__
|
|
#define _AC(X,Y) X
|
|
#define _AT(T,X) X
|
|
#else
|
|
#define __AC(X,Y) (X##Y)
|
|
#define _AC(X,Y) __AC(X,Y)
|
|
#define _AT(T,X) ((T)(X))
|
|
#endif
|
|
|
|
#define _UL(x) (_AC(x, UL))
|
|
#define _ULL(x) (_AC(x, ULL))
|
|
|
|
#define _BITUL(x) (_UL(1) << (x))
|
|
#define _BITULL(x) (_ULL(1) << (x))
|
|
|
|
#if !defined(__ASSEMBLY__)
|
|
/*
|
|
* Missing asm support
|
|
*
|
|
* __BIT128() would not work in the asm code, as it shifts an
|
|
* 'unsigned __init128' data type as direct representation of
|
|
* 128 bit constants is not supported in the gcc compiler, as
|
|
* they get silently truncated.
|
|
*
|
|
* TODO: Please revisit this implementation when gcc compiler
|
|
* starts representing 128 bit constants directly like long
|
|
* and unsigned long etc. Subsequently drop the comment for
|
|
* GENMASK_U128() which would then start supporting asm code.
|
|
*/
|
|
#define _BIT128(x) ((unsigned __int128)(1) << (x))
|
|
#endif
|
|
|
|
#define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (__typeof__(x))(a) - 1)
|
|
#define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask))
|
|
|
|
#define __KERNEL_DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d))
|
|
|
|
#endif /* _UAPI_LINUX_CONST_H */
|