1 /* 2 * Copyright (c) 2016-2018, 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_32(nr) (U(1) << (nr)) 20 #define BIT_64(nr) (ULL(1) << (nr)) 21 22 #ifdef AARCH32 23 #define BIT BIT_32 24 #else 25 #define BIT BIT_64 26 #endif 27 28 /* 29 * Create a contiguous bitmask starting at bit position @l and ending at 30 * position @h. For example 31 * GENMASK_64(39, 21) gives us the 64bit vector 0x000000ffffe00000. 32 */ 33 #if defined(__LINKER__) || defined(__ASSEMBLY__) 34 #define GENMASK_32(h, l) \ 35 (((0xFFFFFFFF) << (l)) & (0xFFFFFFFF >> (32 - 1 - (h)))) 36 37 #define GENMASK_64(h, l) \ 38 ((~0 << (l)) & (~0 >> (64 - 1 - (h)))) 39 #else 40 #define GENMASK_32(h, l) \ 41 (((~UINT32_C(0)) << (l)) & (~UINT32_C(0) >> (32 - 1 - (h)))) 42 43 #define GENMASK_64(h, l) \ 44 (((~UINT64_C(0)) << (l)) & (~UINT64_C(0) >> (64 - 1 - (h)))) 45 #endif 46 47 #ifdef AARCH32 48 #define GENMASK GENMASK_32 49 #else 50 #define GENMASK GENMASK_64 51 #endif 52 53 /* 54 * This variant of div_round_up can be used in macro definition but should not 55 * be used in C code as the `div` parameter is evaluated twice. 56 */ 57 #define DIV_ROUND_UP_2EVAL(n, d) (((n) + (d) - 1) / (d)) 58 59 #define div_round_up(val, div) __extension__ ({ \ 60 __typeof__(div) _div = (div); \ 61 ((val) + _div - (__typeof__(div)) 1) / _div; \ 62 }) 63 64 #define MIN(x, y) __extension__ ({ \ 65 __typeof__(x) _x = (x); \ 66 __typeof__(y) _y = (y); \ 67 (void)(&_x == &_y); \ 68 _x < _y ? _x : _y; \ 69 }) 70 71 #define MAX(x, y) __extension__ ({ \ 72 __typeof__(x) _x = (x); \ 73 __typeof__(y) _y = (y); \ 74 (void)(&_x == &_y); \ 75 _x > _y ? _x : _y; \ 76 }) 77 78 /* 79 * The round_up() macro rounds up a value to the given boundary in a 80 * type-agnostic yet type-safe manner. The boundary must be a power of two. 81 * In other words, it computes the smallest multiple of boundary which is 82 * greater than or equal to value. 83 * 84 * round_down() is similar but rounds the value down instead. 85 */ 86 #define round_boundary(value, boundary) \ 87 ((__typeof__(value))((boundary) - 1)) 88 89 #define round_up(value, boundary) \ 90 ((((value) - 1) | round_boundary(value, boundary)) + 1) 91 92 #define round_down(value, boundary) \ 93 ((value) & ~round_boundary(value, boundary)) 94 95 /* 96 * Evaluates to 1 if (ptr + inc) overflows, 0 otherwise. 97 * Both arguments must be unsigned pointer values (i.e. uintptr_t). 98 */ 99 #define check_uptr_overflow(_ptr, _inc) \ 100 ((_ptr) > (UINTPTR_MAX - (_inc))) 101 102 /* 103 * Evaluates to 1 if (u32 + inc) overflows, 0 otherwise. 104 * Both arguments must be 32-bit unsigned integers (i.e. effectively uint32_t). 105 */ 106 #define check_u32_overflow(_u32, _inc) \ 107 ((_u32) > (UINT32_MAX - (_inc))) 108 109 /* 110 * For those constants to be shared between C and other sources, apply a 'U', 111 * 'UL', 'ULL', 'L' or 'LL' suffix to the argument only in C, to avoid 112 * undefined or unintended behaviour. 113 * 114 * The GNU assembler and linker do not support these suffixes (it causes the 115 * build process to fail) therefore the suffix is omitted when used in linker 116 * scripts and assembler files. 117 */ 118 #if defined(__LINKER__) || defined(__ASSEMBLY__) 119 # define U(_x) (_x) 120 # define UL(_x) (_x) 121 # define ULL(_x) (_x) 122 # define L(_x) (_x) 123 # define LL(_x) (_x) 124 #else 125 # define U(_x) (_x##U) 126 # define UL(_x) (_x##UL) 127 # define ULL(_x) (_x##ULL) 128 # define L(_x) (_x##L) 129 # define LL(_x) (_x##LL) 130 #endif 131 132 /* Register size of the current architecture. */ 133 #ifdef AARCH32 134 #define REGSZ U(4) 135 #else 136 #define REGSZ U(8) 137 #endif 138 139 /* 140 * Test for the current architecture version to be at least the version 141 * expected. 142 */ 143 #define ARM_ARCH_AT_LEAST(_maj, _min) \ 144 ((ARM_ARCH_MAJOR > (_maj)) || \ 145 ((ARM_ARCH_MAJOR == (_maj)) && (ARM_ARCH_MINOR >= (_min)))) 146 147 /* 148 * Import an assembly or linker symbol as a C expression with the specified 149 * type 150 */ 151 #define IMPORT_SYM(type, sym, name) \ 152 extern char sym[];\ 153 static const __attribute__((unused)) type name = (type) sym; 154 155 /* 156 * When the symbol is used to hold a pointer, its alignment can be asserted 157 * with this macro. For example, if there is a linker symbol that is going to 158 * be used as a 64-bit pointer, the value of the linker symbol must also be 159 * aligned to 64 bit. This macro makes sure this is the case. 160 */ 161 #define ASSERT_SYM_PTR_ALIGN(sym) assert(((size_t)(sym) % __alignof__(*(sym))) == 0) 162 163 #define COMPILER_BARRIER() __asm__ volatile ("" ::: "memory") 164 165 /* Compiler builtin of GCC >= 9 and planned in llvm */ 166 #ifdef __HAVE_SPECULATION_SAFE_VALUE 167 # define SPECULATION_SAFE_VALUE(var) __builtin_speculation_safe_value(var) 168 #else 169 # define SPECULATION_SAFE_VALUE(var) var 170 #endif 171 172 #endif /* UTILS_DEF_H */ 173