xref: /openbmc/linux/arch/arm64/include/asm/traps.h (revision 6c33a6f4)
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_entry_text(unsigned long ptr)
46 {
47 	return ptr >= (unsigned long)&__entry_text_start &&
48 	       ptr < (unsigned long)&__entry_text_end;
49 }
50 
51 /*
52  * CPUs with the RAS extensions have an Implementation-Defined-Syndrome bit
53  * to indicate whether this ESR has a RAS encoding. CPUs without this feature
54  * have a ISS-Valid bit in the same position.
55  * If this bit is set, we know its not a RAS SError.
56  * If its clear, we need to know if the CPU supports RAS. Uncategorized RAS
57  * errors share the same encoding as an all-zeros encoding from a CPU that
58  * doesn't support RAS.
59  */
60 static inline bool arm64_is_ras_serror(u32 esr)
61 {
62 	WARN_ON(preemptible());
63 
64 	if (esr & ESR_ELx_IDS)
65 		return false;
66 
67 	if (this_cpu_has_cap(ARM64_HAS_RAS_EXTN))
68 		return true;
69 	else
70 		return false;
71 }
72 
73 /*
74  * Return the AET bits from a RAS SError's ESR.
75  *
76  * It is implementation defined whether Uncategorized errors are containable.
77  * We treat them as Uncontainable.
78  * Non-RAS SError's are reported as Uncontained/Uncategorized.
79  */
80 static inline u32 arm64_ras_serror_get_severity(u32 esr)
81 {
82 	u32 aet = esr & ESR_ELx_AET;
83 
84 	if (!arm64_is_ras_serror(esr)) {
85 		/* Not a RAS error, we can't interpret the ESR. */
86 		return ESR_ELx_AET_UC;
87 	}
88 
89 	/*
90 	 * AET is RES0 if 'the value returned in the DFSC field is not
91 	 * [ESR_ELx_FSC_SERROR]'
92 	 */
93 	if ((esr & ESR_ELx_FSC) != ESR_ELx_FSC_SERROR) {
94 		/* No severity information : Uncategorized */
95 		return ESR_ELx_AET_UC;
96 	}
97 
98 	return aet;
99 }
100 
101 bool arm64_is_fatal_ras_serror(struct pt_regs *regs, unsigned int esr);
102 void __noreturn arm64_serror_panic(struct pt_regs *regs, u32 esr);
103 #endif
104