1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef __HEAD_32_H__ 3 #define __HEAD_32_H__ 4 5 #include <asm/ptrace.h> /* for STACK_FRAME_REGS_MARKER */ 6 7 /* 8 * Exception entry code. This code runs with address translation 9 * turned off, i.e. using physical addresses. 10 * We assume sprg3 has the physical address of the current 11 * task's thread_struct. 12 */ 13 .macro EXCEPTION_PROLOG handle_dar_dsisr=0 14 EXCEPTION_PROLOG_0 handle_dar_dsisr=\handle_dar_dsisr 15 EXCEPTION_PROLOG_1 16 EXCEPTION_PROLOG_2 handle_dar_dsisr=\handle_dar_dsisr 17 .endm 18 19 .macro EXCEPTION_PROLOG_0 handle_dar_dsisr=0 20 mtspr SPRN_SPRG_SCRATCH0,r10 21 mtspr SPRN_SPRG_SCRATCH1,r11 22 #ifdef CONFIG_VMAP_STACK 23 mfspr r10, SPRN_SPRG_THREAD 24 .if \handle_dar_dsisr 25 mfspr r11, SPRN_DAR 26 stw r11, DAR(r10) 27 mfspr r11, SPRN_DSISR 28 stw r11, DSISR(r10) 29 .endif 30 mfspr r11, SPRN_SRR0 31 stw r11, SRR0(r10) 32 #endif 33 mfspr r11, SPRN_SRR1 /* check whether user or kernel */ 34 #ifdef CONFIG_VMAP_STACK 35 stw r11, SRR1(r10) 36 #endif 37 mfcr r10 38 andi. r11, r11, MSR_PR 39 .endm 40 41 .macro EXCEPTION_PROLOG_1 for_rtas=0 42 #ifdef CONFIG_VMAP_STACK 43 mr r11, r1 44 subi r1, r1, INT_FRAME_SIZE /* use r1 if kernel */ 45 beq 1f 46 mfspr r1,SPRN_SPRG_THREAD 47 lwz r1,TASK_STACK-THREAD(r1) 48 addi r1, r1, THREAD_SIZE - INT_FRAME_SIZE 49 #else 50 subi r11, r1, INT_FRAME_SIZE /* use r1 if kernel */ 51 beq 1f 52 mfspr r11,SPRN_SPRG_THREAD 53 lwz r11,TASK_STACK-THREAD(r11) 54 addi r11, r11, THREAD_SIZE - INT_FRAME_SIZE 55 #endif 56 1: 57 tophys_novmstack r11, r11 58 #ifdef CONFIG_VMAP_STACK 59 mtcrf 0x7f, r1 60 bt 32 - THREAD_ALIGN_SHIFT, stack_overflow 61 #endif 62 .endm 63 64 .macro EXCEPTION_PROLOG_2 handle_dar_dsisr=0 65 #ifdef CONFIG_VMAP_STACK 66 mtcr r10 67 li r10, MSR_KERNEL & ~(MSR_IR | MSR_RI) /* can take DTLB miss */ 68 mtmsr r10 69 isync 70 #else 71 stw r10,_CCR(r11) /* save registers */ 72 #endif 73 mfspr r10, SPRN_SPRG_SCRATCH0 74 #ifdef CONFIG_VMAP_STACK 75 stw r11,GPR1(r1) 76 stw r11,0(r1) 77 mr r11, r1 78 #else 79 stw r1,GPR1(r11) 80 stw r1,0(r11) 81 tovirt(r1, r11) /* set new kernel sp */ 82 #endif 83 stw r12,GPR12(r11) 84 stw r9,GPR9(r11) 85 stw r10,GPR10(r11) 86 #ifdef CONFIG_VMAP_STACK 87 mfcr r10 88 stw r10, _CCR(r11) 89 #endif 90 mfspr r12,SPRN_SPRG_SCRATCH1 91 stw r12,GPR11(r11) 92 mflr r10 93 stw r10,_LINK(r11) 94 #ifdef CONFIG_VMAP_STACK 95 mfspr r12, SPRN_SPRG_THREAD 96 tovirt(r12, r12) 97 .if \handle_dar_dsisr 98 lwz r10, DAR(r12) 99 stw r10, _DAR(r11) 100 lwz r10, DSISR(r12) 101 stw r10, _DSISR(r11) 102 .endif 103 lwz r9, SRR1(r12) 104 andi. r10, r9, MSR_PR 105 lwz r12, SRR0(r12) 106 #else 107 mfspr r12,SPRN_SRR0 108 mfspr r9,SPRN_SRR1 109 #endif 110 #ifdef CONFIG_40x 111 rlwinm r9,r9,0,14,12 /* clear MSR_WE (necessary?) */ 112 #else 113 #ifdef CONFIG_VMAP_STACK 114 li r10, MSR_KERNEL & ~MSR_IR /* can take exceptions */ 115 #else 116 li r10,MSR_KERNEL & ~(MSR_IR|MSR_DR) /* can take exceptions */ 117 #endif 118 mtmsr r10 /* (except for mach check in rtas) */ 119 #endif 120 stw r0,GPR0(r11) 121 lis r10,STACK_FRAME_REGS_MARKER@ha /* exception frame marker */ 122 addi r10,r10,STACK_FRAME_REGS_MARKER@l 123 stw r10,8(r11) 124 SAVE_4GPRS(3, r11) 125 SAVE_2GPRS(7, r11) 126 .endm 127 128 .macro SYSCALL_ENTRY trapno 129 mfspr r12,SPRN_SPRG_THREAD 130 mfspr r9, SPRN_SRR1 131 #ifdef CONFIG_VMAP_STACK 132 mfspr r11, SPRN_SRR0 133 mtctr r11 134 #endif 135 andi. r11, r9, MSR_PR 136 lwz r11,TASK_STACK-THREAD(r12) 137 beq- 99f 138 addi r11, r11, THREAD_SIZE - INT_FRAME_SIZE 139 #ifdef CONFIG_VMAP_STACK 140 li r10, MSR_KERNEL & ~(MSR_IR | MSR_RI) /* can take DTLB miss */ 141 mtmsr r10 142 isync 143 #endif 144 tovirt_vmstack r12, r12 145 tophys_novmstack r11, r11 146 mflr r10 147 stw r10, _LINK(r11) 148 #ifdef CONFIG_VMAP_STACK 149 mfctr r10 150 #else 151 mfspr r10,SPRN_SRR0 152 #endif 153 stw r1,GPR1(r11) 154 stw r1,0(r11) 155 tovirt_novmstack r1, r11 /* set new kernel sp */ 156 stw r10,_NIP(r11) 157 mfcr r10 158 rlwinm r10,r10,0,4,2 /* Clear SO bit in CR */ 159 stw r10,_CCR(r11) /* save registers */ 160 #ifdef CONFIG_40x 161 rlwinm r9,r9,0,14,12 /* clear MSR_WE (necessary?) */ 162 #else 163 #ifdef CONFIG_VMAP_STACK 164 LOAD_REG_IMMEDIATE(r10, MSR_KERNEL & ~MSR_IR) /* can take exceptions */ 165 #else 166 LOAD_REG_IMMEDIATE(r10, MSR_KERNEL & ~(MSR_IR|MSR_DR)) /* can take exceptions */ 167 #endif 168 mtmsr r10 /* (except for mach check in rtas) */ 169 #endif 170 lis r10,STACK_FRAME_REGS_MARKER@ha /* exception frame marker */ 171 stw r2,GPR2(r11) 172 addi r10,r10,STACK_FRAME_REGS_MARKER@l 173 stw r9,_MSR(r11) 174 li r2, \trapno + 1 175 stw r10,8(r11) 176 stw r2,_TRAP(r11) 177 SAVE_GPR(0, r11) 178 SAVE_4GPRS(3, r11) 179 SAVE_2GPRS(7, r11) 180 addi r11,r1,STACK_FRAME_OVERHEAD 181 addi r2,r12,-THREAD 182 stw r11,PT_REGS(r12) 183 #if defined(CONFIG_40x) 184 /* Check to see if the dbcr0 register is set up to debug. Use the 185 internal debug mode bit to do this. */ 186 lwz r12,THREAD_DBCR0(r12) 187 andis. r12,r12,DBCR0_IDM@h 188 #endif 189 ACCOUNT_CPU_USER_ENTRY(r2, r11, r12) 190 #if defined(CONFIG_40x) 191 beq+ 3f 192 /* From user and task is ptraced - load up global dbcr0 */ 193 li r12,-1 /* clear all pending debug events */ 194 mtspr SPRN_DBSR,r12 195 lis r11,global_dbcr0@ha 196 tophys(r11,r11) 197 addi r11,r11,global_dbcr0@l 198 lwz r12,0(r11) 199 mtspr SPRN_DBCR0,r12 200 lwz r12,4(r11) 201 addi r12,r12,-1 202 stw r12,4(r11) 203 #endif 204 205 3: 206 tovirt_novmstack r2, r2 /* set r2 to current */ 207 lis r11, transfer_to_syscall@h 208 ori r11, r11, transfer_to_syscall@l 209 #ifdef CONFIG_TRACE_IRQFLAGS 210 /* 211 * If MSR is changing we need to keep interrupts disabled at this point 212 * otherwise we might risk taking an interrupt before we tell lockdep 213 * they are enabled. 214 */ 215 LOAD_REG_IMMEDIATE(r10, MSR_KERNEL) 216 rlwimi r10, r9, 0, MSR_EE 217 #else 218 LOAD_REG_IMMEDIATE(r10, MSR_KERNEL | MSR_EE) 219 #endif 220 #if defined(CONFIG_PPC_8xx) && defined(CONFIG_PERF_EVENTS) 221 mtspr SPRN_NRI, r0 222 #endif 223 mtspr SPRN_SRR1,r10 224 mtspr SPRN_SRR0,r11 225 SYNC 226 RFI /* jump to handler, enable MMU */ 227 99: b ret_from_kernel_syscall 228 .endm 229 230 .macro save_dar_dsisr_on_stack reg1, reg2, sp 231 #ifndef CONFIG_VMAP_STACK 232 mfspr \reg1, SPRN_DAR 233 mfspr \reg2, SPRN_DSISR 234 stw \reg1, _DAR(\sp) 235 stw \reg2, _DSISR(\sp) 236 #endif 237 .endm 238 239 .macro get_and_save_dar_dsisr_on_stack reg1, reg2, sp 240 #ifdef CONFIG_VMAP_STACK 241 lwz \reg1, _DAR(\sp) 242 lwz \reg2, _DSISR(\sp) 243 #else 244 save_dar_dsisr_on_stack \reg1, \reg2, \sp 245 #endif 246 .endm 247 248 .macro tovirt_vmstack dst, src 249 #ifdef CONFIG_VMAP_STACK 250 tovirt(\dst, \src) 251 #else 252 .ifnc \dst, \src 253 mr \dst, \src 254 .endif 255 #endif 256 .endm 257 258 .macro tovirt_novmstack dst, src 259 #ifndef CONFIG_VMAP_STACK 260 tovirt(\dst, \src) 261 #else 262 .ifnc \dst, \src 263 mr \dst, \src 264 .endif 265 #endif 266 .endm 267 268 .macro tophys_novmstack dst, src 269 #ifndef CONFIG_VMAP_STACK 270 tophys(\dst, \src) 271 #else 272 .ifnc \dst, \src 273 mr \dst, \src 274 .endif 275 #endif 276 .endm 277 278 /* 279 * Note: code which follows this uses cr0.eq (set if from kernel), 280 * r11, r12 (SRR0), and r9 (SRR1). 281 * 282 * Note2: once we have set r1 we are in a position to take exceptions 283 * again, and we could thus set MSR:RI at that point. 284 */ 285 286 /* 287 * Exception vectors. 288 */ 289 #ifdef CONFIG_PPC_BOOK3S 290 #define START_EXCEPTION(n, label) \ 291 . = n; \ 292 DO_KVM n; \ 293 label: 294 295 #else 296 #define START_EXCEPTION(n, label) \ 297 . = n; \ 298 label: 299 300 #endif 301 302 #define EXCEPTION(n, label, hdlr, xfer) \ 303 START_EXCEPTION(n, label) \ 304 EXCEPTION_PROLOG; \ 305 addi r3,r1,STACK_FRAME_OVERHEAD; \ 306 xfer(n, hdlr) 307 308 #define EXC_XFER_TEMPLATE(hdlr, trap, msr, tfer, ret) \ 309 li r10,trap; \ 310 stw r10,_TRAP(r11); \ 311 LOAD_REG_IMMEDIATE(r10, msr); \ 312 bl tfer; \ 313 .long hdlr; \ 314 .long ret 315 316 #define EXC_XFER_STD(n, hdlr) \ 317 EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, transfer_to_handler_full, \ 318 ret_from_except_full) 319 320 #define EXC_XFER_LITE(n, hdlr) \ 321 EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, transfer_to_handler, \ 322 ret_from_except) 323 324 .macro vmap_stack_overflow_exception 325 #ifdef CONFIG_VMAP_STACK 326 #ifdef CONFIG_SMP 327 mfspr r1, SPRN_SPRG_THREAD 328 lwz r1, TASK_CPU - THREAD(r1) 329 slwi r1, r1, 3 330 addis r1, r1, emergency_ctx@ha 331 #else 332 lis r1, emergency_ctx@ha 333 #endif 334 lwz r1, emergency_ctx@l(r1) 335 cmpwi cr1, r1, 0 336 bne cr1, 1f 337 lis r1, init_thread_union@ha 338 addi r1, r1, init_thread_union@l 339 1: addi r1, r1, THREAD_SIZE - INT_FRAME_SIZE 340 EXCEPTION_PROLOG_2 341 SAVE_NVGPRS(r11) 342 addi r3, r1, STACK_FRAME_OVERHEAD 343 EXC_XFER_STD(0, stack_overflow_exception) 344 #endif 345 .endm 346 347 #endif /* __HEAD_32_H__ */ 348