xref: /openbmc/linux/arch/arm64/include/asm/traps.h (revision 1a59d1b8)
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, unsigned long address);
39 void arm64_notify_segfault(unsigned long addr);
40 void arm64_force_sig_fault(int signo, int code, void __user *addr, const char *str);
41 void arm64_force_sig_mceerr(int code, void __user *addr, short lsb, const char *str);
42 void arm64_force_sig_ptrace_errno_trap(int errno, void __user *addr, const char *str);
43 
44 /*
45  * Move regs->pc to next instruction and do necessary setup before it
46  * is executed.
47  */
48 void arm64_skip_faulting_instruction(struct pt_regs *regs, unsigned long size);
49 
50 static inline int __in_irqentry_text(unsigned long ptr)
51 {
52 	return ptr >= (unsigned long)&__irqentry_text_start &&
53 	       ptr < (unsigned long)&__irqentry_text_end;
54 }
55 
56 static inline int in_exception_text(unsigned long ptr)
57 {
58 	int in;
59 
60 	in = ptr >= (unsigned long)&__exception_text_start &&
61 	     ptr < (unsigned long)&__exception_text_end;
62 
63 	return in ? : __in_irqentry_text(ptr);
64 }
65 
66 static inline int in_entry_text(unsigned long ptr)
67 {
68 	return ptr >= (unsigned long)&__entry_text_start &&
69 	       ptr < (unsigned long)&__entry_text_end;
70 }
71 
72 /*
73  * CPUs with the RAS extensions have an Implementation-Defined-Syndrome bit
74  * to indicate whether this ESR has a RAS encoding. CPUs without this feature
75  * have a ISS-Valid bit in the same position.
76  * If this bit is set, we know its not a RAS SError.
77  * If its clear, we need to know if the CPU supports RAS. Uncategorized RAS
78  * errors share the same encoding as an all-zeros encoding from a CPU that
79  * doesn't support RAS.
80  */
81 static inline bool arm64_is_ras_serror(u32 esr)
82 {
83 	WARN_ON(preemptible());
84 
85 	if (esr & ESR_ELx_IDS)
86 		return false;
87 
88 	if (this_cpu_has_cap(ARM64_HAS_RAS_EXTN))
89 		return true;
90 	else
91 		return false;
92 }
93 
94 /*
95  * Return the AET bits from a RAS SError's ESR.
96  *
97  * It is implementation defined whether Uncategorized errors are containable.
98  * We treat them as Uncontainable.
99  * Non-RAS SError's are reported as Uncontained/Uncategorized.
100  */
101 static inline u32 arm64_ras_serror_get_severity(u32 esr)
102 {
103 	u32 aet = esr & ESR_ELx_AET;
104 
105 	if (!arm64_is_ras_serror(esr)) {
106 		/* Not a RAS error, we can't interpret the ESR. */
107 		return ESR_ELx_AET_UC;
108 	}
109 
110 	/*
111 	 * AET is RES0 if 'the value returned in the DFSC field is not
112 	 * [ESR_ELx_FSC_SERROR]'
113 	 */
114 	if ((esr & ESR_ELx_FSC) != ESR_ELx_FSC_SERROR) {
115 		/* No severity information : Uncategorized */
116 		return ESR_ELx_AET_UC;
117 	}
118 
119 	return aet;
120 }
121 
122 bool arm64_is_fatal_ras_serror(struct pt_regs *regs, unsigned int esr);
123 void __noreturn arm64_serror_panic(struct pt_regs *regs, u32 esr);
124 #endif
125