1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 #ifndef _ASM_POWERPC_EXCEPTION_H 3 #define _ASM_POWERPC_EXCEPTION_H 4 /* 5 * Extracted from head_64.S 6 * 7 * PowerPC version 8 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) 9 * 10 * Rewritten by Cort Dougan (cort@cs.nmt.edu) for PReP 11 * Copyright (C) 1996 Cort Dougan <cort@cs.nmt.edu> 12 * Adapted for Power Macintosh by Paul Mackerras. 13 * Low-level exception handlers and MMU support 14 * rewritten by Paul Mackerras. 15 * Copyright (C) 1996 Paul Mackerras. 16 * 17 * Adapted for 64bit PowerPC by Dave Engebretsen, Peter Bergner, and 18 * Mike Corrigan {engebret|bergner|mikejc}@us.ibm.com 19 * 20 * This file contains the low-level support and setup for the 21 * PowerPC-64 platform, including trap and interrupt dispatch. 22 */ 23 /* 24 * The following macros define the code that appears as 25 * the prologue to each of the exception handlers. They 26 * are split into two parts to allow a single kernel binary 27 * to be used for pSeries and iSeries. 28 * 29 * We make as much of the exception code common between native 30 * exception handlers (including pSeries LPAR) and iSeries LPAR 31 * implementations as possible. 32 */ 33 #include <asm/feature-fixups.h> 34 35 /* PACA save area size in u64 units (exgen, exmc, etc) */ 36 #define EX_SIZE 10 37 38 /* 39 * maximum recursive depth of MCE exceptions 40 */ 41 #define MAX_MCE_DEPTH 4 42 43 #ifdef __ASSEMBLY__ 44 45 #define STF_ENTRY_BARRIER_SLOT \ 46 STF_ENTRY_BARRIER_FIXUP_SECTION; \ 47 nop; \ 48 nop; \ 49 nop 50 51 #define STF_EXIT_BARRIER_SLOT \ 52 STF_EXIT_BARRIER_FIXUP_SECTION; \ 53 nop; \ 54 nop; \ 55 nop; \ 56 nop; \ 57 nop; \ 58 nop 59 60 #define ENTRY_FLUSH_SLOT \ 61 ENTRY_FLUSH_FIXUP_SECTION; \ 62 nop; \ 63 nop; \ 64 nop; 65 66 #define SCV_ENTRY_FLUSH_SLOT \ 67 SCV_ENTRY_FLUSH_FIXUP_SECTION; \ 68 nop; \ 69 nop; \ 70 nop; 71 72 /* 73 * r10 must be free to use, r13 must be paca 74 */ 75 #define INTERRUPT_TO_KERNEL \ 76 STF_ENTRY_BARRIER_SLOT; \ 77 ENTRY_FLUSH_SLOT 78 79 /* 80 * r10, ctr must be free to use, r13 must be paca 81 */ 82 #define SCV_INTERRUPT_TO_KERNEL \ 83 STF_ENTRY_BARRIER_SLOT; \ 84 SCV_ENTRY_FLUSH_SLOT 85 86 /* 87 * Macros for annotating the expected destination of (h)rfid 88 * 89 * The nop instructions allow us to insert one or more instructions to flush the 90 * L1-D cache when returning to userspace or a guest. 91 * 92 * powerpc relies on return from interrupt/syscall being context synchronising 93 * (which hrfid, rfid, and rfscv are) to support ARCH_HAS_MEMBARRIER_SYNC_CORE 94 * without additional synchronisation instructions. 95 * 96 * soft-masked interrupt replay does not include a context-synchronising rfid, 97 * but those always return to kernel, the sync is only required when returning 98 * to user. 99 */ 100 #define RFI_FLUSH_SLOT \ 101 RFI_FLUSH_FIXUP_SECTION; \ 102 nop; \ 103 nop; \ 104 nop 105 106 #define RFI_TO_KERNEL \ 107 rfid 108 109 #define RFI_TO_USER \ 110 STF_EXIT_BARRIER_SLOT; \ 111 RFI_FLUSH_SLOT; \ 112 rfid; \ 113 b rfi_flush_fallback 114 115 #define RFI_TO_USER_OR_KERNEL \ 116 STF_EXIT_BARRIER_SLOT; \ 117 RFI_FLUSH_SLOT; \ 118 rfid; \ 119 b rfi_flush_fallback 120 121 #define RFI_TO_GUEST \ 122 STF_EXIT_BARRIER_SLOT; \ 123 RFI_FLUSH_SLOT; \ 124 rfid; \ 125 b rfi_flush_fallback 126 127 #define HRFI_TO_KERNEL \ 128 hrfid 129 130 #define HRFI_TO_USER \ 131 STF_EXIT_BARRIER_SLOT; \ 132 RFI_FLUSH_SLOT; \ 133 hrfid; \ 134 b hrfi_flush_fallback 135 136 #define HRFI_TO_USER_OR_KERNEL \ 137 STF_EXIT_BARRIER_SLOT; \ 138 RFI_FLUSH_SLOT; \ 139 hrfid; \ 140 b hrfi_flush_fallback 141 142 #define HRFI_TO_GUEST \ 143 STF_EXIT_BARRIER_SLOT; \ 144 RFI_FLUSH_SLOT; \ 145 hrfid; \ 146 b hrfi_flush_fallback 147 148 #define HRFI_TO_UNKNOWN \ 149 STF_EXIT_BARRIER_SLOT; \ 150 RFI_FLUSH_SLOT; \ 151 hrfid; \ 152 b hrfi_flush_fallback 153 154 #define RFSCV_TO_USER \ 155 STF_EXIT_BARRIER_SLOT; \ 156 RFI_FLUSH_SLOT; \ 157 RFSCV; \ 158 b rfscv_flush_fallback 159 160 #else /* __ASSEMBLY__ */ 161 /* Prototype for function defined in exceptions-64s.S */ 162 void do_uaccess_flush(void); 163 #endif /* __ASSEMBLY__ */ 164 165 #endif /* _ASM_POWERPC_EXCEPTION_H */ 166