1 /* 2 * Copyright (c) 2014, STMicroelectronics International N.V. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright notice, 9 * this list of conditions and the following disclaimer. 10 * 11 * 2. Redistributions in binary form must reproduce the above copyright notice, 12 * this list of conditions and the following disclaimer in the documentation 13 * and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 16 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 19 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 20 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 21 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 22 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 23 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 24 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 25 * POSSIBILITY OF SUCH DAMAGE. 26 */ 27 #ifndef UTIL_H 28 #define UTIL_H 29 30 #include <compiler.h> 31 #include <stdint.h> 32 33 #ifndef MAX 34 #define MAX(a, b) \ 35 (__extension__({ __typeof__(a) _a = (a); \ 36 __typeof__(b) _b = (b); \ 37 _a > _b ? _a : _b; })) 38 39 #define MIN(a, b) \ 40 (__extension__({ __typeof__(a) _a = (a); \ 41 __typeof__(b) _b = (b); \ 42 _a < _b ? _a : _b; })) 43 #endif 44 45 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) 46 47 /* Round up the even multiple of size, size has to be a multiple of 2 */ 48 #define ROUNDUP(v, size) (((v) + ((__typeof__(v))(size) - 1)) & \ 49 ~((__typeof__(v))(size) - 1)) 50 51 /* Round down the even multiple of size, size has to be a multiple of 2 */ 52 #define ROUNDDOWN(v, size) ((v) & ~((__typeof__(v))(size) - 1)) 53 54 /* x has to be of an unsigned type */ 55 #define IS_POWER_OF_TWO(x) (((x) != 0) && (((x) & (~(x) + 1)) == (x))) 56 57 #define ALIGNMENT_IS_OK(p, type) \ 58 (((uintptr_t)(p) & (__alignof__(type) - 1)) == 0) 59 60 #define TO_STR(x) _TO_STR(x) 61 #define _TO_STR(x) #x 62 63 #define container_of(ptr, type, member) \ 64 (__extension__({ \ 65 const typeof(((type *)0)->member) *__ptr = (ptr); \ 66 (type *)((unsigned long)(__ptr) - offsetof(type, member)); \ 67 })) 68 69 #define MEMBER_SIZE(type, member) sizeof(((type *)0)->member) 70 71 #ifdef ASM 72 #define BIT32(nr) (1 << (nr)) 73 #define BIT64(nr) (1 << (nr)) 74 #define SHIFT_U32(v, shift) ((v) << (shift)) 75 #define SHIFT_U64(v, shift) ((v) << (shift)) 76 #else 77 #define BIT32(nr) (UINT32_C(1) << (nr)) 78 #define BIT64(nr) (UINT64_C(1) << (nr)) 79 #define SHIFT_U32(v, shift) ((uint32_t)(v) << (shift)) 80 #define SHIFT_U64(v, shift) ((uint64_t)(v) << (shift)) 81 #endif 82 #define BIT(nr) BIT32(nr) 83 84 /* 85 * Create a contiguous bitmask starting at bit position @l and ending at 86 * position @h. For example 87 * GENMASK_64(39, 21) gives us the 64bit vector 0x000000ffffe00000. 88 */ 89 #define GENMASK_32(h, l) \ 90 (((~UINT32_C(0)) << (l)) & (~UINT32_C(0) >> (32 - 1 - (h)))) 91 92 #define GENMASK_64(h, l) \ 93 (((~UINT64_C(0)) << (l)) & (~UINT64_C(0) >> (64 - 1 - (h)))) 94 95 /* 96 * Checking overflow for addition, subtraction and multiplication. Result 97 * of operation is stored in res which is a pointer to some kind of 98 * integer. 99 * 100 * The macros return true if an overflow occurred and *res is undefined. 101 */ 102 #define ADD_OVERFLOW(a, b, res) __compiler_add_overflow((a), (b), (res)) 103 #define SUB_OVERFLOW(a, b, res) __compiler_sub_overflow((a), (b), (res)) 104 #define MUL_OVERFLOW(a, b, res) __compiler_mul_overflow((a), (b), (res)) 105 106 #endif /*UTIL_H*/ 107