xref: /openbmc/linux/arch/arm64/include/asm/traps.h (revision 20e2fc42)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Based on arch/arm/include/asm/traps.h
4  *
5  * Copyright (C) 2012 ARM Ltd.
6  */
7 #ifndef __ASM_TRAP_H
8 #define __ASM_TRAP_H
9 
10 #include <linux/list.h>
11 #include <asm/esr.h>
12 #include <asm/sections.h>
13 
14 struct pt_regs;
15 
16 struct undef_hook {
17 	struct list_head node;
18 	u32 instr_mask;
19 	u32 instr_val;
20 	u64 pstate_mask;
21 	u64 pstate_val;
22 	int (*fn)(struct pt_regs *regs, u32 instr);
23 };
24 
25 void register_undef_hook(struct undef_hook *hook);
26 void unregister_undef_hook(struct undef_hook *hook);
27 void force_signal_inject(int signal, int code, unsigned long address);
28 void arm64_notify_segfault(unsigned long addr);
29 void arm64_force_sig_fault(int signo, int code, void __user *addr, const char *str);
30 void arm64_force_sig_mceerr(int code, void __user *addr, short lsb, const char *str);
31 void arm64_force_sig_ptrace_errno_trap(int errno, void __user *addr, const char *str);
32 
33 /*
34  * Move regs->pc to next instruction and do necessary setup before it
35  * is executed.
36  */
37 void arm64_skip_faulting_instruction(struct pt_regs *regs, unsigned long size);
38 
39 static inline int __in_irqentry_text(unsigned long ptr)
40 {
41 	return ptr >= (unsigned long)&__irqentry_text_start &&
42 	       ptr < (unsigned long)&__irqentry_text_end;
43 }
44 
45 static inline int in_exception_text(unsigned long ptr)
46 {
47 	int in;
48 
49 	in = ptr >= (unsigned long)&__exception_text_start &&
50 	     ptr < (unsigned long)&__exception_text_end;
51 
52 	return in ? : __in_irqentry_text(ptr);
53 }
54 
55 static inline int in_entry_text(unsigned long ptr)
56 {
57 	return ptr >= (unsigned long)&__entry_text_start &&
58 	       ptr < (unsigned long)&__entry_text_end;
59 }
60 
61 /*
62  * CPUs with the RAS extensions have an Implementation-Defined-Syndrome bit
63  * to indicate whether this ESR has a RAS encoding. CPUs without this feature
64  * have a ISS-Valid bit in the same position.
65  * If this bit is set, we know its not a RAS SError.
66  * If its clear, we need to know if the CPU supports RAS. Uncategorized RAS
67  * errors share the same encoding as an all-zeros encoding from a CPU that
68  * doesn't support RAS.
69  */
70 static inline bool arm64_is_ras_serror(u32 esr)
71 {
72 	WARN_ON(preemptible());
73 
74 	if (esr & ESR_ELx_IDS)
75 		return false;
76 
77 	if (this_cpu_has_cap(ARM64_HAS_RAS_EXTN))
78 		return true;
79 	else
80 		return false;
81 }
82 
83 /*
84  * Return the AET bits from a RAS SError's ESR.
85  *
86  * It is implementation defined whether Uncategorized errors are containable.
87  * We treat them as Uncontainable.
88  * Non-RAS SError's are reported as Uncontained/Uncategorized.
89  */
90 static inline u32 arm64_ras_serror_get_severity(u32 esr)
91 {
92 	u32 aet = esr & ESR_ELx_AET;
93 
94 	if (!arm64_is_ras_serror(esr)) {
95 		/* Not a RAS error, we can't interpret the ESR. */
96 		return ESR_ELx_AET_UC;
97 	}
98 
99 	/*
100 	 * AET is RES0 if 'the value returned in the DFSC field is not
101 	 * [ESR_ELx_FSC_SERROR]'
102 	 */
103 	if ((esr & ESR_ELx_FSC) != ESR_ELx_FSC_SERROR) {
104 		/* No severity information : Uncategorized */
105 		return ESR_ELx_AET_UC;
106 	}
107 
108 	return aet;
109 }
110 
111 bool arm64_is_fatal_ras_serror(struct pt_regs *regs, unsigned int esr);
112 void __noreturn arm64_serror_panic(struct pt_regs *regs, u32 esr);
113 #endif
114