exception.S revision 1.14.50.1
1 /* $NetBSD: exception.S,v 1.14.50.1 2008/01/20 16:03:56 chris Exp $ */ 2 3 /* 4 * Copyright (c) 1994-1997 Mark Brinicombe. 5 * Copyright (c) 1994 Brini. 6 * All rights reserved. 7 * 8 * This code is derived from software written for Brini by Mark Brinicombe 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by Brini. 21 * 4. The name of the company nor the name of the author may be used to 22 * endorse or promote products derived from this software without specific 23 * prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY BRINI ``AS IS'' AND ANY EXPRESS OR IMPLIED 26 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 27 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 28 * IN NO EVENT SHALL BRINI OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 29 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 30 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 31 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 * 37 * RiscBSD kernel project 38 * 39 * exception.S 40 * 41 * Low level handlers for exception vectors 42 * 43 * Created : 24/09/94 44 * 45 * Based on kate/display/abort.s 46 */ 47 48 #include <machine/asm.h> 49 #include <machine/cpu.h> 50 #include <machine/frame.h> 51 #include "assym.h" 52 53 .text 54 .align 0 55 56 AST_ALIGNMENT_FAULT_LOCALS 57 58 /* 59 * reset_entry: 60 * 61 * Handler for Reset exception. 62 */ 63 ASENTRY_NP(reset_entry) 64 adr r0, Lreset_panicmsg 65 mov r1, lr 66 bl _C_LABEL(panic) 67 /* NOTREACHED */ 68 Lreset_panicmsg: 69 .asciz "Reset vector called, LR = 0x%08x" 70 .balign 4 71 72 /* 73 * swi_entry 74 * 75 * Handler for the Software Interrupt exception. 76 */ 77 ASENTRY_NP(swi_entry) 78 PUSHFRAME 79 ENABLE_ALIGNMENT_FAULTS 80 81 mov r0, sp /* Pass the frame to any function */ 82 bl _C_LABEL(swi_handler) /* It's a SWI ! */ 83 84 DO_AST_AND_RESTORE_ALIGNMENT_FAULTS 85 PULLFRAME 86 movs pc, lr /* Exit */ 87 88 /* 89 * prefetch_abort_entry: 90 * 91 * Handler for the Prefetch Abort exception. 92 */ 93 ASENTRY_NP(prefetch_abort_entry) 94 #ifdef __XSCALE__ 95 nop /* Make absolutely sure any pending */ 96 nop /* imprecise aborts have occurred. */ 97 #endif 98 sub lr, lr, #0x00000004 /* Adjust the lr */ 99 100 PUSHFRAMEINSVC 101 ENABLE_ALIGNMENT_FAULTS 102 103 ldr r1, Lprefetch_abort_handler_address 104 adr lr, exception_exit 105 mov r0, sp /* pass the stack pointer as r0 */ 106 ldr pc, [r1] 107 108 Lprefetch_abort_handler_address: 109 .word _C_LABEL(prefetch_abort_handler_address) 110 111 .data 112 .global _C_LABEL(prefetch_abort_handler_address) 113 114 _C_LABEL(prefetch_abort_handler_address): 115 .word abortprefetch 116 117 .text 118 abortprefetch: 119 adr r0, abortprefetchmsg 120 b _C_LABEL(panic) 121 122 abortprefetchmsg: 123 .asciz "abortprefetch" 124 .align 0 125 126 /* 127 * data_abort_entry: 128 * 129 * Handler for the Data Abort exception. 130 */ 131 ASENTRY_NP(data_abort_entry) 132 #ifdef __XSCALE__ 133 nop /* Make absolutely sure any pending */ 134 nop /* imprecise aborts have occurred. */ 135 #endif 136 sub lr, lr, #0x00000008 /* Adjust the lr */ 137 138 PUSHFRAMEINSVC /* Push trap frame and switch */ 139 /* to SVC32 mode */ 140 ENABLE_ALIGNMENT_FAULTS 141 142 ldr r1, Ldata_abort_handler_address 143 adr lr, exception_exit 144 mov r0, sp /* pass the stack pointer as r0 */ 145 ldr pc, [r1] 146 147 Ldata_abort_handler_address: 148 .word _C_LABEL(data_abort_handler_address) 149 150 .data 151 .global _C_LABEL(data_abort_handler_address) 152 _C_LABEL(data_abort_handler_address): 153 .word abortdata 154 155 .text 156 abortdata: 157 adr r0, abortdatamsg 158 b _C_LABEL(panic) 159 160 abortdatamsg: 161 .asciz "abortdata" 162 .align 0 163 164 /* 165 * address_exception_entry: 166 * 167 * Handler for the Address Exception exception. 168 * 169 * NOTE: This exception isn't really used on arm32. We 170 * print a warning message to the console and then treat 171 * it like a Data Abort. 172 */ 173 ASENTRY_NP(address_exception_entry) 174 mrs r1, cpsr_all 175 mrs r2, spsr_all 176 mov r3, lr 177 adr r0, Laddress_exception_msg 178 bl _C_LABEL(printf) /* XXX CLOBBERS LR!! */ 179 b data_abort_entry 180 Laddress_exception_msg: 181 .asciz "Address Exception CPSR=0x%08x SPSR=0x%08x LR=0x%08x\n" 182 .balign 4 183 184 /* 185 * General exception exit handler 186 * (Placed here to be within range of all the references to it) 187 * 188 * It exits straight away if not returning to USR mode. 189 * This loops around delivering any pending ASTs. 190 * Interrupts are disabled at suitable points to avoid ASTs 191 * being posted between testing and exit to user mode. 192 * 193 * This function uses PULLFRAMEFROMSVCANDEXIT and 194 * DO_AST_AND_RESTORE_ALIGNMENT_FAULTS thus should 195 * only be called if the exception handler used PUSHFRAMEINSVC 196 * followed by ENABLE_ALIGNMENT_FAULTS. 197 */ 198 199 exception_exit: 200 DO_AST_AND_RESTORE_ALIGNMENT_FAULTS 201 PULLFRAMEFROMSVCANDEXIT 202 203 /* 204 * undefined_entry: 205 * 206 * Handler for the Undefined Instruction exception. 207 * 208 * We indirect the undefined vector via the handler address 209 * in the data area. Entry to the undefined handler must 210 * look like direct entry from the vector. 211 */ 212 ASENTRY_NP(undefined_entry) 213 stmfd sp!, {r0, r1} 214 ldr r0, Lundefined_handler_indirection 215 ldr r1, [sp], #0x0004 216 str r1, [r0, #0x0000] 217 ldr r1, [sp], #0x0004 218 str r1, [r0, #0x0004] 219 ldmia r0, {r0, r1, pc} 220 221 Lundefined_handler_indirection: 222 .word Lundefined_handler_indirection_data 223 224 /* 225 * assembly bounce code for calling the kernel 226 * undefined instruction handler. This uses 227 * a standard trap frame and is called in SVC mode. 228 */ 229 230 ENTRY_NP(undefinedinstruction_bounce) 231 PUSHFRAMEINSVC 232 ENABLE_ALIGNMENT_FAULTS 233 234 mov r0, sp 235 adr lr, exception_exit 236 b _C_LABEL(undefinedinstruction) 237 238 .data 239 .align 0 240 241 /* 242 * Indirection data 243 * 2 words use for preserving r0 and r1 244 * 3rd word contains the undefined handler address. 245 */ 246 247 Lundefined_handler_indirection_data: 248 .word 0 249 .word 0 250 251 .global _C_LABEL(undefined_handler_address) 252 _C_LABEL(undefined_handler_address): 253 .word _C_LABEL(undefinedinstruction_bounce) 254
Indexes created Thu Oct 02 10:09:58 GMT 2025