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      1 /*
      2  * Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
      3  *
      4  * SPDX-License-Identifier: BSD-3-Clause
      5  */
      6 
      7 #ifndef __UTILS_DEF_H__
      8 #define __UTILS_DEF_H__
      9 
     10 /* Compute the number of elements in the given array */
     11 #define ARRAY_SIZE(a)				\
     12 	(sizeof(a) / sizeof((a)[0]))
     13 
     14 #define IS_POWER_OF_TWO(x)			\
     15 	(((x) & ((x) - 1)) == 0)
     16 
     17 #define SIZE_FROM_LOG2_WORDS(n)		(4 << (n))
     18 
     19 #define BIT(nr)				(1ULL << (nr))
     20 
     21 /*
     22  * This variant of div_round_up can be used in macro definition but should not
     23  * be used in C code as the `div` parameter is evaluated twice.
     24  */
     25 #define DIV_ROUND_UP_2EVAL(n, d)	(((n) + (d) - 1) / (d))
     26 
     27 #define MIN(x, y) __extension__ ({	\
     28 	__typeof__(x) _x = (x);		\
     29 	__typeof__(y) _y = (y);		\
     30 	(void)(&_x == &_y);		\
     31 	_x < _y ? _x : _y;		\
     32 })
     33 
     34 #define MAX(x, y) __extension__ ({	\
     35 	__typeof__(x) _x = (x);		\
     36 	__typeof__(y) _y = (y);		\
     37 	(void)(&_x == &_y);		\
     38 	_x > _y ? _x : _y;		\
     39 })
     40 
     41 /*
     42  * The round_up() macro rounds up a value to the given boundary in a
     43  * type-agnostic yet type-safe manner. The boundary must be a power of two.
     44  * In other words, it computes the smallest multiple of boundary which is
     45  * greater than or equal to value.
     46  *
     47  * round_down() is similar but rounds the value down instead.
     48  */
     49 #define round_boundary(value, boundary)		\
     50 	((__typeof__(value))((boundary) - 1))
     51 
     52 #define round_up(value, boundary)		\
     53 	((((value) - 1) | round_boundary(value, boundary)) + 1)
     54 
     55 #define round_down(value, boundary)		\
     56 	((value) & ~round_boundary(value, boundary))
     57 
     58 #define div_round_up(val, div) __extension__ ({	\
     59 	__typeof__(div) _div = (div);		\
     60 	round_up((val), _div)/_div;		\
     61 })
     62 
     63 /*
     64  * Evaluates to 1 if (ptr + inc) overflows, 0 otherwise.
     65  * Both arguments must be unsigned pointer values (i.e. uintptr_t).
     66  */
     67 #define check_uptr_overflow(ptr, inc)		\
     68 	(((ptr) > UINTPTR_MAX - (inc)) ? 1 : 0)
     69 
     70 /*
     71  * For those constants to be shared between C and other sources, apply a 'u'
     72  * or 'ull' suffix to the argument only in C, to avoid undefined or unintended
     73  * behaviour.
     74  *
     75  * The GNU assembler and linker do not support the 'u' and 'ull' suffix (it
     76  * causes the build process to fail) therefore the suffix is omitted when used
     77  * in linker scripts and assembler files.
     78 */
     79 #if defined(__LINKER__) || defined(__ASSEMBLY__)
     80 # define  U(_x)		(_x)
     81 # define ULL(_x)	(_x)
     82 #else
     83 # define  U(_x)		(_x##u)
     84 # define ULL(_x)	(_x##ull)
     85 #endif
     86 
     87 /*
     88  * Test for the current architecture version to be at least the version
     89  * expected.
     90  */
     91 #define ARM_ARCH_AT_LEAST(_maj, _min) \
     92 	((ARM_ARCH_MAJOR > _maj) || \
     93 	 ((ARM_ARCH_MAJOR == _maj) && (ARM_ARCH_MINOR >= _min)))
     94 
     95 #endif /* __UTILS_DEF_H__ */
     96