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 mtspr SPRN_SPRG_SCRATCH2,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 1: 50 mtcrf 0x3f, r1 51 bt 32 - THREAD_ALIGN_SHIFT, stack_overflow 52 #else 53 subi r11, r1, INT_FRAME_SIZE /* use r1 if kernel */ 54 beq 1f 55 mfspr r11,SPRN_SPRG_THREAD 56 lwz r11,TASK_STACK-THREAD(r11) 57 addi r11, r11, THREAD_SIZE - INT_FRAME_SIZE 58 1: tophys(r11, r11) 59 #endif 60 .endm 61 62 .macro EXCEPTION_PROLOG_2 handle_dar_dsisr=0 63 #ifdef CONFIG_VMAP_STACK 64 li r11, MSR_KERNEL & ~(MSR_IR | MSR_RI) /* can take DTLB miss */ 65 mtmsr r11 66 isync 67 mfspr r11, SPRN_SPRG_SCRATCH2 68 stw r11,GPR1(r1) 69 stw r11,0(r1) 70 mr r11, r1 71 #else 72 stw r1,GPR1(r11) 73 stw r1,0(r11) 74 tovirt(r1, r11) /* set new kernel sp */ 75 #endif 76 stw r10,_CCR(r11) /* save registers */ 77 stw r12,GPR12(r11) 78 stw r9,GPR9(r11) 79 mfspr r10,SPRN_SPRG_SCRATCH0 80 mfspr r12,SPRN_SPRG_SCRATCH1 81 stw r10,GPR10(r11) 82 stw r12,GPR11(r11) 83 mflr r10 84 stw r10,_LINK(r11) 85 #ifdef CONFIG_VMAP_STACK 86 mfspr r12, SPRN_SPRG_THREAD 87 tovirt(r12, r12) 88 .if \handle_dar_dsisr 89 lwz r10, DAR(r12) 90 stw r10, _DAR(r11) 91 lwz r10, DSISR(r12) 92 stw r10, _DSISR(r11) 93 .endif 94 lwz r9, SRR1(r12) 95 lwz r12, SRR0(r12) 96 #else 97 mfspr r12,SPRN_SRR0 98 mfspr r9,SPRN_SRR1 99 #endif 100 #ifdef CONFIG_40x 101 rlwinm r9,r9,0,14,12 /* clear MSR_WE (necessary?) */ 102 #else 103 #ifdef CONFIG_VMAP_STACK 104 li r10, MSR_KERNEL & ~MSR_IR /* can take exceptions */ 105 #else 106 li r10,MSR_KERNEL & ~(MSR_IR|MSR_DR) /* can take exceptions */ 107 #endif 108 mtmsr r10 /* (except for mach check in rtas) */ 109 #endif 110 stw r0,GPR0(r11) 111 lis r10,STACK_FRAME_REGS_MARKER@ha /* exception frame marker */ 112 addi r10,r10,STACK_FRAME_REGS_MARKER@l 113 stw r10,8(r11) 114 SAVE_4GPRS(3, r11) 115 SAVE_2GPRS(7, r11) 116 .endm 117 118 .macro SYSCALL_ENTRY trapno 119 mfspr r9, SPRN_SRR1 120 mfspr r10, SPRN_SRR0 121 LOAD_REG_IMMEDIATE(r11, MSR_KERNEL) /* can take exceptions */ 122 lis r12, 1f@h 123 ori r12, r12, 1f@l 124 mtspr SPRN_SRR1, r11 125 mtspr SPRN_SRR0, r12 126 mfspr r12,SPRN_SPRG_THREAD 127 mr r11, r1 128 lwz r1,TASK_STACK-THREAD(r12) 129 tovirt(r12, r12) 130 addi r1, r1, THREAD_SIZE - INT_FRAME_SIZE 131 rfi 132 1: 133 stw r11,GPR1(r1) 134 stw r11,0(r1) 135 mr r11, r1 136 stw r10,_NIP(r11) 137 mflr r10 138 stw r10, _LINK(r11) 139 mfcr r10 140 rlwinm r10,r10,0,4,2 /* Clear SO bit in CR */ 141 stw r10,_CCR(r11) /* save registers */ 142 #ifdef CONFIG_40x 143 rlwinm r9,r9,0,14,12 /* clear MSR_WE (necessary?) */ 144 #endif 145 lis r10,STACK_FRAME_REGS_MARKER@ha /* exception frame marker */ 146 stw r2,GPR2(r11) 147 addi r10,r10,STACK_FRAME_REGS_MARKER@l 148 stw r9,_MSR(r11) 149 li r2, \trapno 150 stw r10,8(r11) 151 stw r2,_TRAP(r11) 152 SAVE_GPR(0, r11) 153 SAVE_4GPRS(3, r11) 154 SAVE_2GPRS(7, r11) 155 addi r2,r12,-THREAD 156 b transfer_to_syscall /* jump to handler */ 157 .endm 158 159 .macro save_dar_dsisr_on_stack reg1, reg2, sp 160 #ifndef CONFIG_VMAP_STACK 161 mfspr \reg1, SPRN_DAR 162 mfspr \reg2, SPRN_DSISR 163 stw \reg1, _DAR(\sp) 164 stw \reg2, _DSISR(\sp) 165 #endif 166 .endm 167 168 .macro get_and_save_dar_dsisr_on_stack reg1, reg2, sp 169 #ifdef CONFIG_VMAP_STACK 170 lwz \reg1, _DAR(\sp) 171 lwz \reg2, _DSISR(\sp) 172 #else 173 save_dar_dsisr_on_stack \reg1, \reg2, \sp 174 #endif 175 .endm 176 177 .macro tovirt_vmstack dst, src 178 #ifdef CONFIG_VMAP_STACK 179 tovirt(\dst, \src) 180 #else 181 .ifnc \dst, \src 182 mr \dst, \src 183 .endif 184 #endif 185 .endm 186 187 .macro tovirt_novmstack dst, src 188 #ifndef CONFIG_VMAP_STACK 189 tovirt(\dst, \src) 190 #else 191 .ifnc \dst, \src 192 mr \dst, \src 193 .endif 194 #endif 195 .endm 196 197 .macro tophys_novmstack dst, src 198 #ifndef CONFIG_VMAP_STACK 199 tophys(\dst, \src) 200 #else 201 .ifnc \dst, \src 202 mr \dst, \src 203 .endif 204 #endif 205 .endm 206 207 /* 208 * Note: code which follows this uses cr0.eq (set if from kernel), 209 * r11, r12 (SRR0), and r9 (SRR1). 210 * 211 * Note2: once we have set r1 we are in a position to take exceptions 212 * again, and we could thus set MSR:RI at that point. 213 */ 214 215 /* 216 * Exception vectors. 217 */ 218 #ifdef CONFIG_PPC_BOOK3S 219 #define START_EXCEPTION(n, label) \ 220 . = n; \ 221 DO_KVM n; \ 222 label: 223 224 #else 225 #define START_EXCEPTION(n, label) \ 226 . = n; \ 227 label: 228 229 #endif 230 231 #define EXCEPTION(n, label, hdlr, xfer) \ 232 START_EXCEPTION(n, label) \ 233 EXCEPTION_PROLOG; \ 234 addi r3,r1,STACK_FRAME_OVERHEAD; \ 235 xfer(n, hdlr) 236 237 #define EXC_XFER_TEMPLATE(hdlr, trap, msr, tfer, ret) \ 238 li r10,trap; \ 239 stw r10,_TRAP(r11); \ 240 LOAD_REG_IMMEDIATE(r10, msr); \ 241 bl tfer; \ 242 .long hdlr; \ 243 .long ret 244 245 #define EXC_XFER_STD(n, hdlr) \ 246 EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, transfer_to_handler_full, \ 247 ret_from_except_full) 248 249 #define EXC_XFER_LITE(n, hdlr) \ 250 EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, transfer_to_handler, \ 251 ret_from_except) 252 253 .macro vmap_stack_overflow_exception 254 #ifdef CONFIG_VMAP_STACK 255 #ifdef CONFIG_SMP 256 mfspr r1, SPRN_SPRG_THREAD 257 lwz r1, TASK_CPU - THREAD(r1) 258 slwi r1, r1, 3 259 addis r1, r1, emergency_ctx@ha 260 #else 261 lis r1, emergency_ctx@ha 262 #endif 263 lwz r1, emergency_ctx@l(r1) 264 cmpwi cr1, r1, 0 265 bne cr1, 1f 266 lis r1, init_thread_union@ha 267 addi r1, r1, init_thread_union@l 268 1: addi r1, r1, THREAD_SIZE - INT_FRAME_SIZE 269 EXCEPTION_PROLOG_2 270 SAVE_NVGPRS(r11) 271 addi r3, r1, STACK_FRAME_OVERHEAD 272 EXC_XFER_STD(0, stack_overflow_exception) 273 #endif 274 .endm 275 276 #endif /* __HEAD_32_H__ */ 277