1 /* 2 * Copyright (c) 2007 Apple Inc. All rights reserved. 3 * 4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ 5 * 6 * This file contains Original Code and/or Modifications of Original Code 7 * as defined in and that are subject to the Apple Public Source License 8 * Version 2.0 (the 'License'). You may not use this file except in 9 * compliance with the License. The rights granted to you under the License 10 * may not be used to create, or enable the creation or redistribution of, 11 * unlawful or unlicensed copies of an Apple operating system, or to 12 * circumvent, violate, or enable the circumvention or violation of, any 13 * terms of an Apple operating system software license agreement. 14 * 15 * Please obtain a copy of the License at 16 * http://www.opensource.apple.com/apsl/ and read it before using this file. 17 * 18 * The Original Code and all software distributed under the License are 19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 23 * Please see the License for the specific language governing rights and 24 * limitations under the License. 25 * 26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ 27 */ 28 /* 29 * @OSF_COPYRIGHT@ 30 */ 31 /* 32 * Mach Operating System 33 * Copyright (c) 1991,1990,1989 Carnegie Mellon University 34 * All Rights Reserved. 35 * 36 * Permission to use, copy, modify and distribute this software and its 37 * documentation is hereby granted, provided that both the copyright 38 * notice and this permission notice appear in all copies of the 39 * software, derivative works or modified versions, and any portions 40 * thereof, and that both notices appear in supporting documentation. 41 * 42 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 43 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR 44 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 45 * 46 * Carnegie Mellon requests users of this software to return to 47 * 48 * Software Distribution Coordinator or [email protected] 49 * School of Computer Science 50 * Carnegie Mellon University 51 * Pittsburgh PA 15213-3890 52 * 53 * any improvements or extensions that they make and grant Carnegie Mellon 54 * the rights to redistribute these changes. 55 */ 56 57 #ifndef _ARM_ASM_H_ 58 #define _ARM_ASM_H_ 59 60 #if defined (__arm__) || defined (__arm64__) 61 62 #include <arm/arch.h> 63 64 #define FRAME pushl %ebp; movl %esp, %ebp 65 #define EMARF leave 66 67 68 /* There is another definition of ALIGN for .c sources */ 69 #ifdef ASSEMBLER 70 #define ALIGN 2 71 #endif /* ASSEMBLER */ 72 73 #ifndef FALIGN 74 #define FALIGN ALIGN 75 #endif 76 77 #define LB(x,n) n 78 #if __STDC__ 79 #ifndef __NO_UNDERSCORES__ 80 #define LCL(x) L ## x 81 #define EXT(x) _ ## x 82 #define LEXT(x) _ ## x ## : 83 #else 84 #define LCL(x) .L ## x 85 #define EXT(x) x 86 #define LEXT(x) x ## : 87 #endif 88 #define LBc(x,n) n ## : 89 #define LBb(x,n) n ## b 90 #define LBf(x,n) n ## f 91 #else /* __STDC__ */ 92 #ifndef __NO_UNDERSCORES__ 93 #define LCL(x) L/**/x 94 #define EXT(x) _/**/x 95 #define LEXT(x) _/**/x/**/: 96 #else /* __NO_UNDERSCORES__ */ 97 #define LCL(x) .L/**/x 98 #define EXT(x) x 99 #define LEXT(x) x/**/: 100 #endif /* __NO_UNDERSCORES__ */ 101 #define LBc(x,n) n/**/: 102 #define LBb(x,n) n/**/b 103 #define LBf(x,n) n/**/f 104 #endif /* __STDC__ */ 105 106 #define String .asciz 107 #define Value .word 108 #define Times(a,b) (a*b) 109 #define Divide(a,b) (a/b) 110 111 #if 0 /* TOTOJK */ 112 #ifdef __ELF__ 113 #define ELF_FUNC(x) .type x,@function 114 #define ELF_DATA(x) .type x,@object 115 #define ELF_SIZE(x,s) .size x,s 116 #else 117 #define ELF_FUNC(x) 118 #define ELF_DATA(x) 119 #define ELF_SIZE(x,s) 120 #endif 121 #else 122 #define ELF_FUNC(x) 123 #define ELF_DATA(x) 124 #define ELF_SIZE(x,s) 125 #endif /* TODOJK */ 126 127 #define Entry(x) .globl EXT(x); ELF_FUNC(EXT(x)); .align FALIGN; LEXT(x) 128 #define ENTRY(x) Entry(x) MCOUNT 129 #define ENTRY2(x,y) .globl EXT(x); .globl EXT(y); \ 130 ELF_FUNC(EXT(x)); ELF_FUNC(EXT(y)); \ 131 .align FALIGN; LEXT(x); LEXT(y) \ 132 MCOUNT 133 #if __STDC__ 134 #define ASENTRY(x) .globl x; .align FALIGN; x ## : ELF_FUNC(x) MCOUNT 135 #else 136 #define ASENTRY(x) .globl x; .align FALIGN; x: ELF_FUNC(x) MCOUNT 137 #endif /* __STDC__ */ 138 139 #define DATA(x) .globl EXT(x); ELF_DATA(EXT(x)); .align ALIGN; LEXT(x) 140 141 #define End(x) ELF_SIZE(x,.-x) 142 #define END(x) End(EXT(x)) 143 #define ENDDATA(x) END(x) 144 #define Enddata(x) End(x) 145 146 #ifdef ASSEMBLER 147 148 #define MCOUNT 149 150 #else /* NOT ASSEMBLER */ 151 152 /* These defines are here for .c files that wish to reference global symbols 153 * within __asm__ statements. 154 */ 155 #ifndef __NO_UNDERSCORES__ 156 #define CC_SYM_PREFIX "_" 157 #else 158 #define CC_SYM_PREFIX "" 159 #endif /* __NO_UNDERSCORES__ */ 160 #endif /* ASSEMBLER */ 161 162 #ifdef ASSEMBLER 163 164 #if defined (_ARM_ARCH_4T) 165 # define RET bx lr 166 # define RETeq bxeq lr 167 # define RETne bxne lr 168 # ifdef __STDC__ 169 # define RETc(c) bx##c lr 170 # else 171 # define RETc(c) bx/**/c lr 172 # endif 173 #else 174 # define RET mov pc, lr 175 # define RETeq moveq pc, lr 176 # define RETne movne pc, lr 177 # ifdef __STDC__ 178 # define RETc(c) mov##c pc, lr 179 # else 180 # define RETc(c) mov/**/c pc, lr 181 # endif 182 #endif 183 184 #if defined (__thumb__) 185 /* Provide a PI mechanism for thumb branching. */ 186 # define BRANCH_EXTERN(x) ldr pc, [pc, #-4] ; \ 187 .long EXT(x) 188 #else 189 # define BRANCH_EXTERN(x) b EXT(x) 190 #endif 191 192 /* 193 * arg0: Register for thread pointer 194 */ 195 .macro READ_THREAD 196 mrc p15, 0, $0, c13, c0, 4 /* Read TPIDRPRW */ 197 .endmacro 198 199 200 /* Macros for loading up addresses that are external to the .s file. 201 * LOAD_ADDR: loads the address for (label) into (reg). Not safe for 202 * loading to the PC. 203 * LOAD_ADDR_PC: Variant for loading to the PC; load the address of (label) 204 * into the pc. 205 * LOAD_ADDR_GEN_DEF: The general definition needed to support loading 206 * a label address. 207 * 208 * Usage: For any label accessed, we require one (and only one) instance 209 * of LOAD_ADDR_GEN_DEF(label). 210 * 211 * Example: 212 * LOAD_ADDR(r0, arm_init) 213 * LOAD_ADDR(lr, arm_init_cpu) 214 * LOAD_ADDR_PC(arm_init) 215 * ... 216 * 217 * LOAD_ADDR_GEN_DEF(arm_init) 218 * LOAD_ADDR_GEN_DEF(arm_init_cpu) 219 */ 220 221 #if SLIDABLE 222 /* Definitions for a position dependent kernel using non-lazy pointers. 223 */ 224 225 /* TODO: Make this work with thumb .s files. */ 226 #define PC_INC 0x8 227 228 /* We need wrapper macros in order to ensure that __LINE__ is expanded. 229 * 230 * There is some small potential for duplicate labels here, but because 231 * we do not export the generated labels, it should not be an issue. 232 */ 233 234 #define GLUE_LABEL_GUTS(label, tag) L_##label##_##tag##_glue 235 #define GLUE_LABEL(label, tag) GLUE_LABEL_GUTS(label, tag) 236 237 #define LOAD_ADDR(reg, label) \ 238 movw reg, :lower16:(label##$non_lazy_ptr - (GLUE_LABEL(label, __LINE__) + PC_INC)) ; \ 239 movt reg, :upper16:(label##$non_lazy_ptr - (GLUE_LABEL(label, __LINE__) + PC_INC)) ; \ 240 GLUE_LABEL(label, __LINE__): ; \ 241 ldr reg, [pc, reg] 242 243 /* Designed with the understanding that directly branching to thumb code 244 * is unreliable; this should allow for dealing with __thumb__ in 245 * assembly; the non-thumb variant still needs to provide the glue label 246 * to avoid failing to build on undefined symbols. 247 * 248 * TODO: Make this actually use a scratch register; this macro is convenient 249 * for translating (ldr pc, [?]) to a slidable format without the risk of 250 * clobbering registers, but it is also wasteful. 251 */ 252 #if defined(__thumb__) 253 #define LOAD_ADDR_PC(label) \ 254 stmfd sp!, { r0 } ; \ 255 stmfd sp!, { r0 } ; \ 256 LOAD_ADDR(r0, label) ; \ 257 str r0, [sp, #4] ; \ 258 ldmfd sp!, { r0 } ; \ 259 ldmfd sp!, { pc } 260 #else 261 #define LOAD_ADDR_PC(label) \ 262 b EXT(label) 263 #endif 264 265 #define LOAD_ADDR_GEN_DEF(label) \ 266 .section __DATA,__nl_symbol_ptr,non_lazy_symbol_pointers ; \ 267 .align 2 ; \ 268 label##$non_lazy_ptr: ; \ 269 .indirect_symbol EXT(label) ; \ 270 .long 0 271 272 #else /* !SLIDABLE */ 273 274 /* Definitions for a position dependent kernel */ 275 #define LOAD_ADDR(reg, label) \ 276 ldr reg, L_##label 277 278 #if defined(__thumb__) 279 #define LOAD_ADDR_PC(label) \ 280 ldr pc, L_##label 281 #else 282 #define LOAD_ADDR_PC(label) \ 283 b EXT(label) 284 #endif 285 286 #define LOAD_ADDR_GEN_DEF(label) \ 287 .text ; \ 288 .align 2 ; \ 289 L_##label: ; \ 290 .long EXT(label) 291 292 #endif /* SLIDABLE */ 293 294 /* The linker can deal with branching from ARM to thumb in unconditional 295 * branches, but not in conditional branches. To support this in our 296 * assembly (which allows us to build xnu without -mno-thumb), use the 297 * following macros for branching conditionally to external symbols. 298 * These macros are used just like the corresponding conditional branch 299 * instructions. 300 */ 301 302 #define SHIM_LABEL_GUTS(line_num) L_cond_extern_##line_num##_shim 303 #define SHIM_LABEL(line_num) SHIM_LABEL_GUTS(line_num) 304 305 #define COND_EXTERN_BEQ(label) \ 306 bne SHIM_LABEL(__LINE__) ; \ 307 b EXT(label) ; \ 308 SHIM_LABEL(__LINE__): 309 310 #define COND_EXTERN_BLNE(label) \ 311 beq SHIM_LABEL(__LINE__) ; \ 312 bl EXT(label) ; \ 313 SHIM_LABEL(__LINE__): 314 315 #define COND_EXTERN_BLGT(label) \ 316 ble SHIM_LABEL(__LINE__) ; \ 317 bl EXT(label) ; \ 318 SHIM_LABEL(__LINE__): 319 320 #endif /* ASSEMBLER */ 321 322 #endif /* defined (__arm__) || defined (__arm64__) */ 323 324 #endif /* _ARM_ASM_H_ */ 325