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/*
* Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of ARM nor the names of its contributors may be used
* to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef __UTILS_H__
#define __UTILS_H__
/* Compute the number of elements in the given array */
#define ARRAY_SIZE(a) \
(sizeof(a) / sizeof((a)[0]))
#define IS_POWER_OF_TWO(x) \
(((x) & ((x) - 1)) == 0)
#define SIZE_FROM_LOG2_WORDS(n) (4 << (n))
#define BIT(nr) (1UL << (nr))
/*
* The round_up() macro rounds up a value to the given boundary in a
* type-agnostic yet type-safe manner. The boundary must be a power of two.
* In other words, it computes the smallest multiple of boundary which is
* greater than or equal to value.
*
* round_down() is similar but rounds the value down instead.
*/
#define round_boundary(value, boundary) \
((__typeof__(value))((boundary) - 1))
#define round_up(value, boundary) \
((((value) - 1) | round_boundary(value, boundary)) + 1)
#define round_down(value, boundary) \
((value) & ~round_boundary(value, boundary))
/*
* Evaluates to 1 if (ptr + inc) overflows, 0 otherwise.
* Both arguments must be unsigned pointer values (i.e. uintptr_t).
*/
#define check_uptr_overflow(ptr, inc) \
(((ptr) > UINTPTR_MAX - (inc)) ? 1 : 0)
/*
* For those constants to be shared between C and other sources, apply a 'ull'
* suffix to the argument only in C, to avoid undefined or unintended behaviour.
*
* The GNU assembler and linker do not support the 'ull' suffix (it causes the
* build process to fail) therefore the suffix is omitted when used in linker
* scripts and assembler files.
*/
#if defined(__LINKER__) || defined(__ASSEMBLY__)
# define ULL(_x) (_x)
#else
# define ULL(_x) (_x##ull)
#endif
/*
* C code should be put in this part of the header to avoid breaking ASM files
* or linker scripts including it.
*/
#if !(defined(__LINKER__) || defined(__ASSEMBLY__))
#include <types.h>
/*
* Fill a region of normal memory of size "length" in bytes with zero bytes.
*
* WARNING: This function can only operate on normal memory. This means that
* the MMU must be enabled when using this function. Otherwise, use
* zeromem.
*/
void zero_normalmem(void *mem, u_register_t length);
/*
* Fill a region of memory of size "length" in bytes with null bytes.
*
* Unlike zero_normalmem, this function has no restriction on the type of
* memory targeted and can be used for any device memory as well as normal
* memory. This function must be used instead of zero_normalmem when MMU is
* disabled.
*
* NOTE: When data cache and MMU are enabled, prefer zero_normalmem for faster
* zeroing.
*/
void zeromem(void *mem, u_register_t length);
#endif /* !(defined(__LINKER__) || defined(__ASSEMBLY__)) */
#endif /* __UTILS_H__ */