arch/arm64/include/asm/traps.h

   1 /*
   2  * Based on arch/arm/include/asm/traps.h
   3  *
   4  * Copyright (C) 2012 ARM Ltd.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18 #ifndef __ASM_TRAP_H
  19 #define __ASM_TRAP_H
  20
  21 #include <linux/list.h>
  22 #include <asm/esr.h>
  23 #include <asm/sections.h>
  24
  25 struct pt_regs;
  26
  27 struct undef_hook {
  28         struct list_head node;
  29         u32 instr_mask;
  30         u32 instr_val;
  31         u64 pstate_mask;
  32         u64 pstate_val;
  33         int (*fn)(struct pt_regs *regs, u32 instr);
  34 };
  35
  36 void register_undef_hook(struct undef_hook *hook);
  37 void unregister_undef_hook(struct undef_hook *hook);
  38 void force_signal_inject(int signal, int code, struct pt_regs *regs,
  39                          unsigned long address);
  40
  41 void arm64_notify_segfault(struct pt_regs *regs, unsigned long addr);
  42
  43 /*
  44  * Move regs->pc to next instruction and do necessary setup before it
  45  * is executed.
  46  */
  47 void arm64_skip_faulting_instruction(struct pt_regs *regs, unsigned long size);
  48
  49 static inline int __in_irqentry_text(unsigned long ptr)
  50 {
  51         return ptr >= (unsigned long)&__irqentry_text_start &&
  52                ptr < (unsigned long)&__irqentry_text_end;
  53 }
  54
  55 static inline int in_exception_text(unsigned long ptr)
  56 {
  57         int in;
  58
  59         in = ptr >= (unsigned long)&__exception_text_start &&
  60              ptr < (unsigned long)&__exception_text_end;
  61
  62         return in ? : __in_irqentry_text(ptr);
  63 }
  64
  65 static inline int in_entry_text(unsigned long ptr)
  66 {
  67         return ptr >= (unsigned long)&__entry_text_start &&
  68                ptr < (unsigned long)&__entry_text_end;
  69 }
  70
  71 /*
  72  * CPUs with the RAS extensions have an Implementation-Defined-Syndrome bit
  73  * to indicate whether this ESR has a RAS encoding. CPUs without this feature
  74  * have a ISS-Valid bit in the same position.
  75  * If this bit is set, we know its not a RAS SError.
  76  * If its clear, we need to know if the CPU supports RAS. Uncategorized RAS
  77  * errors share the same encoding as an all-zeros encoding from a CPU that
  78  * doesn't support RAS.
  79  */
  80 static inline bool arm64_is_ras_serror(u32 esr)
  81 {
  82         WARN_ON(preemptible());
  83
  84         if (esr & ESR_ELx_IDS)
  85                 return false;
  86
  87         if (this_cpu_has_cap(ARM64_HAS_RAS_EXTN))
  88                 return true;
  89         else
  90                 return false;
  91 }
  92
  93 /*
  94  * Return the AET bits from a RAS SError's ESR.
  95  *
  96  * It is implementation defined whether Uncategorized errors are containable.
  97  * We treat them as Uncontainable.
  98  * Non-RAS SError's are reported as Uncontained/Uncategorized.
  99  */
 100 static inline u32 arm64_ras_serror_get_severity(u32 esr)
 101 {
 102         u32 aet = esr & ESR_ELx_AET;
 103
 104         if (!arm64_is_ras_serror(esr)) {
 105                 /* Not a RAS error, we can't interpret the ESR. */
 106                 return ESR_ELx_AET_UC;
 107         }
 108
 109         /*
 110          * AET is RES0 if 'the value returned in the DFSC field is not
 111          * [ESR_ELx_FSC_SERROR]'
 112          */
 113         if ((esr & ESR_ELx_FSC) != ESR_ELx_FSC_SERROR) {
 114                 /* No severity information : Uncategorized */
 115                 return ESR_ELx_AET_UC;
 116         }
 117
 118         return aet;
 119 }
 120
 121 bool arm64_is_fatal_ras_serror(struct pt_regs *regs, unsigned int esr);
 122 void __noreturn arm64_serror_panic(struct pt_regs *regs, u32 esr);
 123 #endif