arch/powerpc/include/asm/exception-64s.h

   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 /* PACA save area offsets */
  39 #define EX_R9           0
  40 #define EX_R10          8
  41 #define EX_R11          16
  42 #define EX_R12          24
  43 #define EX_R13          32
  44 #define EX_DAR          40
  45 #define EX_DSISR        48
  46 #define EX_CCR          52
  47 #define EX_CFAR         56
  48 #define EX_PPR          64
  49 #define EX_CTR          72
  50
  51 /*
  52  * maximum recursive depth of MCE exceptions
  53  */
  54 #define MAX_MCE_DEPTH   4
  55
  56 #ifdef __ASSEMBLY__
  57
  58 #define STF_ENTRY_BARRIER_SLOT                                          \
  59         STF_ENTRY_BARRIER_FIXUP_SECTION;                                \
  60         nop;                                                            \
  61         nop;                                                            \
  62         nop
  63
  64 #define STF_EXIT_BARRIER_SLOT                                           \
  65         STF_EXIT_BARRIER_FIXUP_SECTION;                                 \
  66         nop;                                                            \
  67         nop;                                                            \
  68         nop;                                                            \
  69         nop;                                                            \
  70         nop;                                                            \
  71         nop
  72
  73 #define ENTRY_FLUSH_SLOT                                                \
  74         ENTRY_FLUSH_FIXUP_SECTION;                                      \
  75         nop;                                                            \
  76         nop;                                                            \
  77         nop;
  78
  79 #define SCV_ENTRY_FLUSH_SLOT                                            \
  80         SCV_ENTRY_FLUSH_FIXUP_SECTION;                                  \
  81         nop;                                                            \
  82         nop;                                                            \
  83         nop;
  84
  85 /*
  86  * r10 must be free to use, r13 must be paca
  87  */
  88 #define INTERRUPT_TO_KERNEL                                             \
  89         STF_ENTRY_BARRIER_SLOT;                                         \
  90         ENTRY_FLUSH_SLOT
  91
  92 /*
  93  * r10, ctr must be free to use, r13 must be paca
  94  */
  95 #define SCV_INTERRUPT_TO_KERNEL                                         \
  96         STF_ENTRY_BARRIER_SLOT;                                         \
  97         SCV_ENTRY_FLUSH_SLOT
  98
  99 /*
 100  * Macros for annotating the expected destination of (h)rfid
 101  *
 102  * The nop instructions allow us to insert one or more instructions to flush the
 103  * L1-D cache when returning to userspace or a guest.
 104  *
 105  * powerpc relies on return from interrupt/syscall being context synchronising
 106  * (which hrfid, rfid, and rfscv are) to support ARCH_HAS_MEMBARRIER_SYNC_CORE
 107  * without additional synchronisation instructions.
 108  *
 109  * soft-masked interrupt replay does not include a context-synchronising rfid,
 110  * but those always return to kernel, the sync is only required when returning
 111  * to user.
 112  */
 113 #define RFI_FLUSH_SLOT                                                  \
 114         RFI_FLUSH_FIXUP_SECTION;                                        \
 115         nop;                                                            \
 116         nop;                                                            \
 117         nop
 118
 119 #define RFI_TO_KERNEL                                                   \
 120         rfid
 121
 122 #define RFI_TO_USER                                                     \
 123         STF_EXIT_BARRIER_SLOT;                                          \
 124         RFI_FLUSH_SLOT;                                                 \
 125         rfid;                                                           \
 126         b       rfi_flush_fallback
 127
 128 #define RFI_TO_USER_OR_KERNEL                                           \
 129         STF_EXIT_BARRIER_SLOT;                                          \
 130         RFI_FLUSH_SLOT;                                                 \
 131         rfid;                                                           \
 132         b       rfi_flush_fallback
 133
 134 #define RFI_TO_GUEST                                                    \
 135         STF_EXIT_BARRIER_SLOT;                                          \
 136         RFI_FLUSH_SLOT;                                                 \
 137         rfid;                                                           \
 138         b       rfi_flush_fallback
 139
 140 #define HRFI_TO_KERNEL                                                  \
 141         hrfid
 142
 143 #define HRFI_TO_USER                                                    \
 144         STF_EXIT_BARRIER_SLOT;                                          \
 145         RFI_FLUSH_SLOT;                                                 \
 146         hrfid;                                                          \
 147         b       hrfi_flush_fallback
 148
 149 #define HRFI_TO_USER_OR_KERNEL                                          \
 150         STF_EXIT_BARRIER_SLOT;                                          \
 151         RFI_FLUSH_SLOT;                                                 \
 152         hrfid;                                                          \
 153         b       hrfi_flush_fallback
 154
 155 #define HRFI_TO_GUEST                                                   \
 156         STF_EXIT_BARRIER_SLOT;                                          \
 157         RFI_FLUSH_SLOT;                                                 \
 158         hrfid;                                                          \
 159         b       hrfi_flush_fallback
 160
 161 #define HRFI_TO_UNKNOWN                                                 \
 162         STF_EXIT_BARRIER_SLOT;                                          \
 163         RFI_FLUSH_SLOT;                                                 \
 164         hrfid;                                                          \
 165         b       hrfi_flush_fallback
 166
 167 #define RFSCV_TO_USER                                                   \
 168         STF_EXIT_BARRIER_SLOT;                                          \
 169         RFI_FLUSH_SLOT;                                                 \
 170         RFSCV;                                                          \
 171         b       rfscv_flush_fallback
 172
 173 #else /* __ASSEMBLY__ */
 174 /* Prototype for function defined in exceptions-64s.S */
 175 void do_uaccess_flush(void);
 176 #endif /* __ASSEMBLY__ */
 177
 178 #endif  /* _ASM_POWERPC_EXCEPTION_H */