1 /* 2 * include/asm-xtensa/asmmacro.h 3 * 4 * This file is subject to the terms and conditions of the GNU General Public 5 * License. See the file "COPYING" in the main directory of this archive 6 * for more details. 7 * 8 * Copyright (C) 2005 Tensilica Inc. 9 */ 10 11 #ifndef _XTENSA_ASMMACRO_H 12 #define _XTENSA_ASMMACRO_H 13 14 #include <asm/core.h> 15 16 /* 17 * Some little helpers for loops. Use zero-overhead-loops 18 * where applicable and if supported by the processor. 19 * 20 * __loopi ar, at, size, inc 21 * ar register initialized with the start address 22 * at scratch register used by macro 23 * size size immediate value 24 * inc increment 25 * 26 * __loops ar, as, at, inc_log2[, mask_log2][, cond][, ncond] 27 * ar register initialized with the start address 28 * as register initialized with the size 29 * at scratch register use by macro 30 * inc_log2 increment [in log2] 31 * mask_log2 mask [in log2] 32 * cond true condition (used in loop'cond') 33 * ncond false condition (used in b'ncond') 34 * 35 * __loop as 36 * restart loop. 'as' register must not have been modified! 37 * 38 * __endla ar, as, incr 39 * ar start address (modified) 40 * as scratch register used by __loops/__loopi macros or 41 * end address used by __loopt macro 42 * inc increment 43 */ 44 45 /* 46 * loop for given size as immediate 47 */ 48 49 .macro __loopi ar, at, size, incr 50 51 #if XCHAL_HAVE_LOOPS 52 movi \at, ((\size + \incr - 1) / (\incr)) 53 loop \at, 99f 54 #else 55 addi \at, \ar, \size 56 98: 57 #endif 58 59 .endm 60 61 /* 62 * loop for given size in register 63 */ 64 65 .macro __loops ar, as, at, incr_log2, mask_log2, cond, ncond 66 67 #if XCHAL_HAVE_LOOPS 68 .ifgt \incr_log2 - 1 69 addi \at, \as, (1 << \incr_log2) - 1 70 .ifnc \mask_log2, 71 extui \at, \at, \incr_log2, \mask_log2 72 .else 73 srli \at, \at, \incr_log2 74 .endif 75 .endif 76 loop\cond \at, 99f 77 #else 78 .ifnc \mask_log2, 79 extui \at, \as, \incr_log2, \mask_log2 80 .else 81 .ifnc \ncond, 82 srli \at, \as, \incr_log2 83 .endif 84 .endif 85 .ifnc \ncond, 86 b\ncond \at, 99f 87 88 .endif 89 .ifnc \mask_log2, 90 slli \at, \at, \incr_log2 91 add \at, \ar, \at 92 .else 93 add \at, \ar, \as 94 .endif 95 #endif 96 98: 97 98 .endm 99 100 /* 101 * loop from ar to as 102 */ 103 104 .macro __loopt ar, as, at, incr_log2 105 106 #if XCHAL_HAVE_LOOPS 107 sub \at, \as, \ar 108 .ifgt \incr_log2 - 1 109 addi \at, \at, (1 << \incr_log2) - 1 110 srli \at, \at, \incr_log2 111 .endif 112 loop \at, 99f 113 #else 114 98: 115 #endif 116 117 .endm 118 119 /* 120 * restart loop. registers must be unchanged 121 */ 122 123 .macro __loop as 124 125 #if XCHAL_HAVE_LOOPS 126 loop \as, 99f 127 #else 128 98: 129 #endif 130 131 .endm 132 133 /* 134 * end of loop with no increment of the address. 135 */ 136 137 .macro __endl ar, as 138 #if !XCHAL_HAVE_LOOPS 139 bltu \ar, \as, 98b 140 #endif 141 99: 142 .endm 143 144 /* 145 * end of loop with increment of the address. 146 */ 147 148 .macro __endla ar, as, incr 149 addi \ar, \ar, \incr 150 __endl \ar \as 151 .endm 152 153 /* Load or store instructions that may cause exceptions use the EX macro. */ 154 155 #define EX(handler) \ 156 .section __ex_table, "a"; \ 157 .word 97f, handler; \ 158 .previous \ 159 97: 160 161 162 /* 163 * Extract unaligned word that is split between two registers w0 and w1 164 * into r regardless of machine endianness. SAR must be loaded with the 165 * starting bit of the word (see __ssa8). 166 */ 167 168 .macro __src_b r, w0, w1 169 #ifdef __XTENSA_EB__ 170 src \r, \w0, \w1 171 #else 172 src \r, \w1, \w0 173 #endif 174 .endm 175 176 /* 177 * Load 2 lowest address bits of r into SAR for __src_b to extract unaligned 178 * word starting at r from two registers loaded from consecutive aligned 179 * addresses covering r regardless of machine endianness. 180 * 181 * r 0 1 2 3 182 * LE SAR 0 8 16 24 183 * BE SAR 32 24 16 8 184 */ 185 186 .macro __ssa8 r 187 #ifdef __XTENSA_EB__ 188 ssa8b \r 189 #else 190 ssa8l \r 191 #endif 192 .endm 193 194 #endif /* _XTENSA_ASMMACRO_H */ 195