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 0x3f, 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 andi. r11, r9, MSR_PR 135 mr r11, r1 136 lwz r1,TASK_STACK-THREAD(r12) 137 beq- 99f 138 addi r1, r1, THREAD_SIZE - INT_FRAME_SIZE 139 li r10, MSR_KERNEL & ~(MSR_IR | MSR_RI) /* can take DTLB miss */ 140 mtmsr r10 141 isync 142 tovirt(r12, r12) 143 stw r11,GPR1(r1) 144 stw r11,0(r1) 145 mr r11, r1 146 #else 147 andi. r11, r9, MSR_PR 148 lwz r11,TASK_STACK-THREAD(r12) 149 beq- 99f 150 addi r11, r11, THREAD_SIZE - INT_FRAME_SIZE 151 tophys(r11, r11) 152 stw r1,GPR1(r11) 153 stw r1,0(r11) 154 tovirt(r1, r11) /* set new kernel sp */ 155 #endif 156 mflr r10 157 stw r10, _LINK(r11) 158 #ifdef CONFIG_VMAP_STACK 159 mfctr r10 160 #else 161 mfspr r10,SPRN_SRR0 162 #endif 163 stw r10,_NIP(r11) 164 mfcr r10 165 rlwinm r10,r10,0,4,2 /* Clear SO bit in CR */ 166 stw r10,_CCR(r11) /* save registers */ 167 #ifdef CONFIG_40x 168 rlwinm r9,r9,0,14,12 /* clear MSR_WE (necessary?) */ 169 #else 170 #ifdef CONFIG_VMAP_STACK 171 LOAD_REG_IMMEDIATE(r10, MSR_KERNEL & ~MSR_IR) /* can take exceptions */ 172 #else 173 LOAD_REG_IMMEDIATE(r10, MSR_KERNEL & ~(MSR_IR|MSR_DR)) /* can take exceptions */ 174 #endif 175 mtmsr r10 /* (except for mach check in rtas) */ 176 #endif 177 lis r10,STACK_FRAME_REGS_MARKER@ha /* exception frame marker */ 178 stw r2,GPR2(r11) 179 addi r10,r10,STACK_FRAME_REGS_MARKER@l 180 stw r9,_MSR(r11) 181 li r2, \trapno + 1 182 stw r10,8(r11) 183 stw r2,_TRAP(r11) 184 SAVE_GPR(0, r11) 185 SAVE_4GPRS(3, r11) 186 SAVE_2GPRS(7, r11) 187 addi r11,r1,STACK_FRAME_OVERHEAD 188 addi r2,r12,-THREAD 189 stw r11,PT_REGS(r12) 190 #if defined(CONFIG_40x) 191 /* Check to see if the dbcr0 register is set up to debug. Use the 192 internal debug mode bit to do this. */ 193 lwz r12,THREAD_DBCR0(r12) 194 andis. r12,r12,DBCR0_IDM@h 195 #endif 196 ACCOUNT_CPU_USER_ENTRY(r2, r11, r12) 197 #if defined(CONFIG_40x) 198 beq+ 3f 199 /* From user and task is ptraced - load up global dbcr0 */ 200 li r12,-1 /* clear all pending debug events */ 201 mtspr SPRN_DBSR,r12 202 lis r11,global_dbcr0@ha 203 tophys(r11,r11) 204 addi r11,r11,global_dbcr0@l 205 lwz r12,0(r11) 206 mtspr SPRN_DBCR0,r12 207 lwz r12,4(r11) 208 addi r12,r12,-1 209 stw r12,4(r11) 210 #endif 211 212 3: 213 tovirt_novmstack r2, r2 /* set r2 to current */ 214 lis r11, transfer_to_syscall@h 215 ori r11, r11, transfer_to_syscall@l 216 #ifdef CONFIG_TRACE_IRQFLAGS 217 /* 218 * If MSR is changing we need to keep interrupts disabled at this point 219 * otherwise we might risk taking an interrupt before we tell lockdep 220 * they are enabled. 221 */ 222 LOAD_REG_IMMEDIATE(r10, MSR_KERNEL) 223 rlwimi r10, r9, 0, MSR_EE 224 #else 225 LOAD_REG_IMMEDIATE(r10, MSR_KERNEL | MSR_EE) 226 #endif 227 #if defined(CONFIG_PPC_8xx) && defined(CONFIG_PERF_EVENTS) 228 mtspr SPRN_NRI, r0 229 #endif 230 mtspr SPRN_SRR1,r10 231 mtspr SPRN_SRR0,r11 232 RFI /* jump to handler, enable MMU */ 233 99: b ret_from_kernel_syscall 234 .endm 235 236 .macro save_dar_dsisr_on_stack reg1, reg2, sp 237 #ifndef CONFIG_VMAP_STACK 238 mfspr \reg1, SPRN_DAR 239 mfspr \reg2, SPRN_DSISR 240 stw \reg1, _DAR(\sp) 241 stw \reg2, _DSISR(\sp) 242 #endif 243 .endm 244 245 .macro get_and_save_dar_dsisr_on_stack reg1, reg2, sp 246 #ifdef CONFIG_VMAP_STACK 247 lwz \reg1, _DAR(\sp) 248 lwz \reg2, _DSISR(\sp) 249 #else 250 save_dar_dsisr_on_stack \reg1, \reg2, \sp 251 #endif 252 .endm 253 254 .macro tovirt_vmstack dst, src 255 #ifdef CONFIG_VMAP_STACK 256 tovirt(\dst, \src) 257 #else 258 .ifnc \dst, \src 259 mr \dst, \src 260 .endif 261 #endif 262 .endm 263 264 .macro tovirt_novmstack dst, src 265 #ifndef CONFIG_VMAP_STACK 266 tovirt(\dst, \src) 267 #else 268 .ifnc \dst, \src 269 mr \dst, \src 270 .endif 271 #endif 272 .endm 273 274 .macro tophys_novmstack dst, src 275 #ifndef CONFIG_VMAP_STACK 276 tophys(\dst, \src) 277 #else 278 .ifnc \dst, \src 279 mr \dst, \src 280 .endif 281 #endif 282 .endm 283 284 /* 285 * Note: code which follows this uses cr0.eq (set if from kernel), 286 * r11, r12 (SRR0), and r9 (SRR1). 287 * 288 * Note2: once we have set r1 we are in a position to take exceptions 289 * again, and we could thus set MSR:RI at that point. 290 */ 291 292 /* 293 * Exception vectors. 294 */ 295 #ifdef CONFIG_PPC_BOOK3S 296 #define START_EXCEPTION(n, label) \ 297 . = n; \ 298 DO_KVM n; \ 299 label: 300 301 #else 302 #define START_EXCEPTION(n, label) \ 303 . = n; \ 304 label: 305 306 #endif 307 308 #define EXCEPTION(n, label, hdlr, xfer) \ 309 START_EXCEPTION(n, label) \ 310 EXCEPTION_PROLOG; \ 311 addi r3,r1,STACK_FRAME_OVERHEAD; \ 312 xfer(n, hdlr) 313 314 #define EXC_XFER_TEMPLATE(hdlr, trap, msr, tfer, ret) \ 315 li r10,trap; \ 316 stw r10,_TRAP(r11); \ 317 LOAD_REG_IMMEDIATE(r10, msr); \ 318 bl tfer; \ 319 .long hdlr; \ 320 .long ret 321 322 #define EXC_XFER_STD(n, hdlr) \ 323 EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, transfer_to_handler_full, \ 324 ret_from_except_full) 325 326 #define EXC_XFER_LITE(n, hdlr) \ 327 EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, transfer_to_handler, \ 328 ret_from_except) 329 330 .macro vmap_stack_overflow_exception 331 #ifdef CONFIG_VMAP_STACK 332 #ifdef CONFIG_SMP 333 mfspr r1, SPRN_SPRG_THREAD 334 lwz r1, TASK_CPU - THREAD(r1) 335 slwi r1, r1, 3 336 addis r1, r1, emergency_ctx-PAGE_OFFSET@ha 337 #else 338 lis r1, emergency_ctx-PAGE_OFFSET@ha 339 #endif 340 lwz r1, emergency_ctx-PAGE_OFFSET@l(r1) 341 addi r1, r1, THREAD_SIZE - INT_FRAME_SIZE 342 EXCEPTION_PROLOG_2 343 SAVE_NVGPRS(r11) 344 addi r3, r1, STACK_FRAME_OVERHEAD 345 EXC_XFER_STD(0, stack_overflow_exception) 346 #endif 347 .endm 348 349 #endif /* __HEAD_32_H__ */ 350