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 trapno name handle_dar_dsisr=0 14 EXCEPTION_PROLOG_0 handle_dar_dsisr=\handle_dar_dsisr 15 EXCEPTION_PROLOG_1 16 EXCEPTION_PROLOG_2 \trapno \name 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 mfspr r10, SPRN_SPRG_THREAD 23 .if \handle_dar_dsisr 24 mfspr r11, SPRN_DAR 25 stw r11, DAR(r10) 26 mfspr r11, SPRN_DSISR 27 stw r11, DSISR(r10) 28 .endif 29 mfspr r11, SPRN_SRR0 30 stw r11, SRR0(r10) 31 mfspr r11, SPRN_SRR1 /* check whether user or kernel */ 32 stw r11, SRR1(r10) 33 mfcr r10 34 andi. r11, r11, MSR_PR 35 .endm 36 37 .macro EXCEPTION_PROLOG_1 38 mtspr SPRN_SPRG_SCRATCH2,r1 39 subi r1, r1, INT_FRAME_SIZE /* use r1 if kernel */ 40 beq 1f 41 mfspr r1,SPRN_SPRG_THREAD 42 lwz r1,TASK_STACK-THREAD(r1) 43 addi r1, r1, THREAD_SIZE - INT_FRAME_SIZE 44 1: 45 #ifdef CONFIG_VMAP_STACK 46 mtcrf 0x3f, r1 47 bt 32 - THREAD_ALIGN_SHIFT, vmap_stack_overflow 48 #endif 49 .endm 50 51 .macro EXCEPTION_PROLOG_2 trapno name handle_dar_dsisr=0 52 #ifdef CONFIG_PPC_8xx 53 .if \handle_dar_dsisr 54 li r11, RPN_PATTERN 55 mtspr SPRN_DAR, r11 /* Tag DAR, to be used in DTLB Error */ 56 .endif 57 #endif 58 LOAD_REG_IMMEDIATE(r11, MSR_KERNEL & ~MSR_RI) /* re-enable MMU */ 59 mtspr SPRN_SRR1, r11 60 lis r11, 1f@h 61 ori r11, r11, 1f@l 62 mtspr SPRN_SRR0, r11 63 mfspr r11, SPRN_SPRG_SCRATCH2 64 rfi 65 66 .text 67 \name\()_virt: 68 1: 69 stw r11,GPR1(r1) 70 stw r11,0(r1) 71 mr r11, r1 72 stw r10,_CCR(r11) /* save registers */ 73 stw r12,GPR12(r11) 74 stw r9,GPR9(r11) 75 mfspr r10,SPRN_SPRG_SCRATCH0 76 mfspr r12,SPRN_SPRG_SCRATCH1 77 stw r10,GPR10(r11) 78 stw r12,GPR11(r11) 79 mflr r10 80 stw r10,_LINK(r11) 81 mfspr r12, SPRN_SPRG_THREAD 82 tovirt(r12, r12) 83 .if \handle_dar_dsisr 84 lwz r10, DAR(r12) 85 stw r10, _DAR(r11) 86 lwz r10, DSISR(r12) 87 stw r10, _DSISR(r11) 88 .endif 89 lwz r9, SRR1(r12) 90 lwz r12, SRR0(r12) 91 #ifdef CONFIG_PPC_8xx 92 mtspr SPRN_EID, r2 /* Set MSR_RI */ 93 #else 94 li r10, MSR_KERNEL /* can take exceptions */ 95 mtmsr r10 /* (except for mach check in rtas) */ 96 #endif 97 COMMON_EXCEPTION_PROLOG_END \trapno 98 _ASM_NOKPROBE_SYMBOL(\name\()_virt) 99 .endm 100 101 .macro COMMON_EXCEPTION_PROLOG_END trapno 102 stw r0,GPR0(r1) 103 lis r10,STACK_FRAME_REGS_MARKER@ha /* exception frame marker */ 104 addi r10,r10,STACK_FRAME_REGS_MARKER@l 105 stw r10,STACK_INT_FRAME_MARKER(r1) 106 li r10, \trapno 107 stw r10,_TRAP(r1) 108 SAVE_GPRS(3, 8, r1) 109 SAVE_NVGPRS(r1) 110 stw r2,GPR2(r1) 111 stw r12,_NIP(r1) 112 stw r9,_MSR(r1) 113 mfctr r10 114 mfspr r2,SPRN_SPRG_THREAD 115 stw r10,_CTR(r1) 116 tovirt(r2, r2) 117 mfspr r10,SPRN_XER 118 addi r2, r2, -THREAD 119 stw r10,_XER(r1) 120 addi r3,r1,STACK_INT_FRAME_REGS 121 .endm 122 123 .macro prepare_transfer_to_handler 124 #ifdef CONFIG_PPC_BOOK3S_32 125 andi. r12,r9,MSR_PR 126 bne 777f 127 bl prepare_transfer_to_handler 128 #ifdef CONFIG_PPC_KUEP 129 b 778f 130 777: 131 bl __kuep_lock 132 778: 133 #endif 134 777: 135 #endif 136 .endm 137 138 .macro SYSCALL_ENTRY trapno 139 mfspr r9, SPRN_SRR1 140 mfspr r12, SPRN_SRR0 141 LOAD_REG_IMMEDIATE(r11, MSR_KERNEL) /* can take exceptions */ 142 lis r10, 1f@h 143 ori r10, r10, 1f@l 144 mtspr SPRN_SRR1, r11 145 mtspr SPRN_SRR0, r10 146 mfspr r10,SPRN_SPRG_THREAD 147 mr r11, r1 148 lwz r1,TASK_STACK-THREAD(r10) 149 tovirt(r10, r10) 150 addi r1, r1, THREAD_SIZE - INT_FRAME_SIZE 151 rfi 152 1: 153 stw r12,_NIP(r1) 154 mfcr r12 155 rlwinm r12,r12,0,4,2 /* Clear SO bit in CR */ 156 stw r12,_CCR(r1) 157 b transfer_to_syscall /* jump to handler */ 158 .endm 159 160 /* 161 * Note: code which follows this uses cr0.eq (set if from kernel), 162 * r11, r12 (SRR0), and r9 (SRR1). 163 * 164 * Note2: once we have set r1 we are in a position to take exceptions 165 * again, and we could thus set MSR:RI at that point. 166 */ 167 168 /* 169 * Exception vectors. 170 */ 171 #ifdef CONFIG_PPC_BOOK3S 172 #define START_EXCEPTION(n, label) \ 173 __HEAD; \ 174 . = n; \ 175 DO_KVM n; \ 176 label: 177 178 #else 179 #define START_EXCEPTION(n, label) \ 180 __HEAD; \ 181 . = n; \ 182 label: 183 184 #endif 185 186 #define EXCEPTION(n, label, hdlr) \ 187 START_EXCEPTION(n, label) \ 188 EXCEPTION_PROLOG n label; \ 189 prepare_transfer_to_handler; \ 190 bl hdlr; \ 191 b interrupt_return 192 193 .macro vmap_stack_overflow_exception 194 __HEAD 195 vmap_stack_overflow: 196 #ifdef CONFIG_SMP 197 mfspr r1, SPRN_SPRG_THREAD 198 lwz r1, TASK_CPU - THREAD(r1) 199 slwi r1, r1, 3 200 addis r1, r1, emergency_ctx-PAGE_OFFSET@ha 201 #else 202 lis r1, emergency_ctx-PAGE_OFFSET@ha 203 #endif 204 lwz r1, emergency_ctx-PAGE_OFFSET@l(r1) 205 addi r1, r1, THREAD_SIZE - INT_FRAME_SIZE 206 EXCEPTION_PROLOG_2 0 vmap_stack_overflow 207 prepare_transfer_to_handler 208 bl stack_overflow_exception 209 b interrupt_return 210 .endm 211 212 #endif /* __HEAD_32_H__ */ 213