1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 /* 3 * vectors - Generic ARM exception table code 4 * 5 * Copyright (c) 1998 Dan Malek <dmalek (at) jlc.net> 6 * Copyright (c) 1999 Magnus Damm <kieraypc01.p.y.kie.era.ericsson.se> 7 * Copyright (c) 2000 Wolfgang Denk <wd (at) denx.de> 8 * Copyright (c) 2001 Alex Zpke <azu (at) sysgo.de> 9 * Copyright (c) 2001 Marius Grger <mag (at) sysgo.de> 10 * Copyright (c) 2002 Alex Zpke <azu (at) sysgo.de> 11 * Copyright (c) 2002 Gary Jennejohn <garyj (at) denx.de> 12 * Copyright (c) 2002 Kyle Harris <kharris (at) nexus-tech.net> 13 */ 14 15 #include <config.h> 16 17 /* 18 * A macro to allow insertion of an ARM exception vector either 19 * for the non-boot0 case or by a boot0-header. 20 */ 21 .macro ARM_VECTORS 22 b reset 23 ldr pc, _undefined_instruction 24 ldr pc, _software_interrupt 25 ldr pc, _prefetch_abort 26 ldr pc, _data_abort 27 ldr pc, _not_used 28 ldr pc, _irq 29 ldr pc, _fiq 30 .endm 31 32 33 /* 34 ************************************************************************* 35 * 36 * Symbol _start is referenced elsewhere, so make it global 37 * 38 ************************************************************************* 39 */ 40 41 .globl _start 42 43 /* 44 ************************************************************************* 45 * 46 * Vectors have their own section so linker script can map them easily 47 * 48 ************************************************************************* 49 */ 50 51 .section ".vectors", "ax" 52 53 #if defined(CONFIG_ENABLE_ARM_SOC_BOOT0_HOOK) 54 /* 55 * Various SoCs need something special and SoC-specific up front in 56 * order to boot, allow them to set that in their boot0.h file and then 57 * use it here. 58 * 59 * To allow a boot0 hook to insert a 'special' sequence after the vector 60 * table (e.g. for the socfpga), the presence of a boot0 hook supresses 61 * the below vector table and assumes that the vector table is filled in 62 * by the boot0 hook. The requirements for a boot0 hook thus are: 63 * (1) defines '_start:' as appropriate 64 * (2) inserts the vector table using ARM_VECTORS as appropriate 65 */ 66 #include <asm/arch/boot0.h> 67 68 #else 69 70 /* 71 ************************************************************************* 72 * 73 * Exception vectors as described in ARM reference manuals 74 * 75 * Uses indirect branch to allow reaching handlers anywhere in memory. 76 * 77 ************************************************************************* 78 */ 79 80 _start: 81 #ifdef CONFIG_SYS_DV_NOR_BOOT_CFG 82 .word CONFIG_SYS_DV_NOR_BOOT_CFG 83 #endif 84 ARM_VECTORS 85 #endif /* !defined(CONFIG_ENABLE_ARM_SOC_BOOT0_HOOK) */ 86 87 /* 88 ************************************************************************* 89 * 90 * Indirect vectors table 91 * 92 * Symbols referenced here must be defined somewhere else 93 * 94 ************************************************************************* 95 */ 96 97 .globl _undefined_instruction 98 .globl _software_interrupt 99 .globl _prefetch_abort 100 .globl _data_abort 101 .globl _not_used 102 .globl _irq 103 .globl _fiq 104 105 _undefined_instruction: .word undefined_instruction 106 _software_interrupt: .word software_interrupt 107 _prefetch_abort: .word prefetch_abort 108 _data_abort: .word data_abort 109 _not_used: .word not_used 110 _irq: .word irq 111 _fiq: .word fiq 112 113 .balignl 16,0xdeadbeef 114 115 /* 116 ************************************************************************* 117 * 118 * Interrupt handling 119 * 120 ************************************************************************* 121 */ 122 123 /* SPL interrupt handling: just hang */ 124 125 #ifdef CONFIG_SPL_BUILD 126 127 .align 5 128 undefined_instruction: 129 software_interrupt: 130 prefetch_abort: 131 data_abort: 132 not_used: 133 irq: 134 fiq: 135 1: 136 b 1b /* hang and never return */ 137 138 #else /* !CONFIG_SPL_BUILD */ 139 140 /* IRQ stack memory (calculated at run-time) + 8 bytes */ 141 .globl IRQ_STACK_START_IN 142 IRQ_STACK_START_IN: 143 #ifdef IRAM_BASE_ADDR 144 .word IRAM_BASE_ADDR + 0x20 145 #else 146 .word 0x0badc0de 147 #endif 148 149 @ 150 @ IRQ stack frame. 151 @ 152 #define S_FRAME_SIZE 72 153 154 #define S_OLD_R0 68 155 #define S_PSR 64 156 #define S_PC 60 157 #define S_LR 56 158 #define S_SP 52 159 160 #define S_IP 48 161 #define S_FP 44 162 #define S_R10 40 163 #define S_R9 36 164 #define S_R8 32 165 #define S_R7 28 166 #define S_R6 24 167 #define S_R5 20 168 #define S_R4 16 169 #define S_R3 12 170 #define S_R2 8 171 #define S_R1 4 172 #define S_R0 0 173 174 #define MODE_SVC 0x13 175 #define I_BIT 0x80 176 177 /* 178 * use bad_save_user_regs for abort/prefetch/undef/swi ... 179 * use irq_save_user_regs / irq_restore_user_regs for IRQ/FIQ handling 180 */ 181 182 .macro bad_save_user_regs 183 @ carve out a frame on current user stack 184 sub sp, sp, #S_FRAME_SIZE 185 stmia sp, {r0 - r12} @ Save user registers (now in svc mode) r0-r12 186 ldr r2, IRQ_STACK_START_IN 187 @ get values for "aborted" pc and cpsr (into parm regs) 188 ldmia r2, {r2 - r3} 189 add r0, sp, #S_FRAME_SIZE @ grab pointer to old stack 190 add r5, sp, #S_SP 191 mov r1, lr 192 stmia r5, {r0 - r3} @ save sp_SVC, lr_SVC, pc, cpsr 193 mov r0, sp @ save current stack into r0 (param register) 194 .endm 195 196 .macro irq_save_user_regs 197 sub sp, sp, #S_FRAME_SIZE 198 stmia sp, {r0 - r12} @ Calling r0-r12 199 @ !!!! R8 NEEDS to be saved !!!! a reserved stack spot would be good. 200 add r8, sp, #S_PC 201 stmdb r8, {sp, lr}^ @ Calling SP, LR 202 str lr, [r8, #0] @ Save calling PC 203 mrs r6, spsr 204 str r6, [r8, #4] @ Save CPSR 205 str r0, [r8, #8] @ Save OLD_R0 206 mov r0, sp 207 .endm 208 209 .macro irq_restore_user_regs 210 ldmia sp, {r0 - lr}^ @ Calling r0 - lr 211 mov r0, r0 212 ldr lr, [sp, #S_PC] @ Get PC 213 add sp, sp, #S_FRAME_SIZE 214 subs pc, lr, #4 @ return & move spsr_svc into cpsr 215 .endm 216 217 .macro get_bad_stack 218 ldr r13, IRQ_STACK_START_IN @ setup our mode stack 219 220 str lr, [r13] @ save caller lr in position 0 of saved stack 221 mrs lr, spsr @ get the spsr 222 str lr, [r13, #4] @ save spsr in position 1 of saved stack 223 mov r13, #MODE_SVC @ prepare SVC-Mode 224 @ msr spsr_c, r13 225 msr spsr, r13 @ switch modes, make sure moves will execute 226 mov lr, pc @ capture return pc 227 movs pc, lr @ jump to next instruction & switch modes. 228 .endm 229 230 .macro get_irq_stack @ setup IRQ stack 231 ldr sp, IRQ_STACK_START 232 .endm 233 234 .macro get_fiq_stack @ setup FIQ stack 235 ldr sp, FIQ_STACK_START 236 .endm 237 238 /* 239 * exception handlers 240 */ 241 242 .align 5 243 undefined_instruction: 244 get_bad_stack 245 bad_save_user_regs 246 bl do_undefined_instruction 247 248 .align 5 249 software_interrupt: 250 get_bad_stack 251 bad_save_user_regs 252 bl do_software_interrupt 253 254 .align 5 255 prefetch_abort: 256 get_bad_stack 257 bad_save_user_regs 258 bl do_prefetch_abort 259 260 .align 5 261 data_abort: 262 get_bad_stack 263 bad_save_user_regs 264 bl do_data_abort 265 266 .align 5 267 not_used: 268 get_bad_stack 269 bad_save_user_regs 270 bl do_not_used 271 272 273 .align 5 274 irq: 275 get_bad_stack 276 bad_save_user_regs 277 bl do_irq 278 279 .align 5 280 fiq: 281 get_bad_stack 282 bad_save_user_regs 283 bl do_fiq 284 285 #endif /* CONFIG_SPL_BUILD */ 286