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1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Copyright (C) 2012 ARM Ltd.
4 */
5#ifndef __ASM_SMP_H
6#define __ASM_SMP_H
7
8#include <linux/const.h>
9
10/* Values for secondary_data.status */
11#define CPU_STUCK_REASON_SHIFT (8)
12#define CPU_BOOT_STATUS_MASK ((UL(1) << CPU_STUCK_REASON_SHIFT) - 1)
13
14#define CPU_MMU_OFF (-1)
15#define CPU_BOOT_SUCCESS (0)
16/* The cpu invoked ops->cpu_die, synchronise it with cpu_kill */
17#define CPU_KILL_ME (1)
18/* The cpu couldn't die gracefully and is looping in the kernel */
19#define CPU_STUCK_IN_KERNEL (2)
20/* Fatal system error detected by secondary CPU, crash the system */
21#define CPU_PANIC_KERNEL (3)
22
23#define CPU_STUCK_REASON_52_BIT_VA (UL(1) << CPU_STUCK_REASON_SHIFT)
24#define CPU_STUCK_REASON_NO_GRAN (UL(2) << CPU_STUCK_REASON_SHIFT)
25
26#ifndef __ASSEMBLY__
27
28#include <asm/percpu.h>
29
30#include <linux/threads.h>
31#include <linux/cpumask.h>
32#include <linux/thread_info.h>
33
34DECLARE_PER_CPU_READ_MOSTLY(int, cpu_number);
35
36/*
37 * We don't use this_cpu_read(cpu_number) as that has implicit writes to
38 * preempt_count, and associated (compiler) barriers, that we'd like to avoid
39 * the expense of. If we're preemptible, the value can be stale at use anyway.
40 * And we can't use this_cpu_ptr() either, as that winds up recursing back
41 * here under CONFIG_DEBUG_PREEMPT=y.
42 */
43#define raw_smp_processor_id() (*raw_cpu_ptr(&cpu_number))
44
45/*
46 * Logical CPU mapping.
47 */
48extern u64 __cpu_logical_map[NR_CPUS];
49extern u64 cpu_logical_map(unsigned int cpu);
50
51static inline void set_cpu_logical_map(unsigned int cpu, u64 hwid)
52{
53 __cpu_logical_map[cpu] = hwid;
54}
55
56struct seq_file;
57
58/*
59 * Discover the set of possible CPUs and determine their
60 * SMP operations.
61 */
62extern void smp_init_cpus(void);
63
64/*
65 * Register IPI interrupts with the arch SMP code
66 */
67extern void set_smp_ipi_range(int ipi_base, int nr_ipi);
68
69/*
70 * Called from the secondary holding pen, this is the secondary CPU entry point.
71 */
72asmlinkage void secondary_start_kernel(void);
73
74/*
75 * Initial data for bringing up a secondary CPU.
76 * @status - Result passed back from the secondary CPU to
77 * indicate failure.
78 */
79struct secondary_data {
80 struct task_struct *task;
81 long status;
82};
83
84extern struct secondary_data secondary_data;
85extern long __early_cpu_boot_status;
86extern void secondary_entry(void);
87
88extern void arch_send_call_function_single_ipi(int cpu);
89extern void arch_send_call_function_ipi_mask(const struct cpumask *mask);
90
91#ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL
92extern void arch_send_wakeup_ipi_mask(const struct cpumask *mask);
93#else
94static inline void arch_send_wakeup_ipi_mask(const struct cpumask *mask)
95{
96 BUILD_BUG();
97}
98#endif
99
100extern int __cpu_disable(void);
101
102extern void __cpu_die(unsigned int cpu);
103extern void cpu_die(void);
104extern void cpu_die_early(void);
105
106static inline void cpu_park_loop(void)
107{
108 for (;;) {
109 wfe();
110 wfi();
111 }
112}
113
114static inline void update_cpu_boot_status(int val)
115{
116 WRITE_ONCE(secondary_data.status, val);
117 /* Ensure the visibility of the status update */
118 dsb(ishst);
119}
120
121/*
122 * The calling secondary CPU has detected serious configuration mismatch,
123 * which calls for a kernel panic. Update the boot status and park the calling
124 * CPU.
125 */
126static inline void cpu_panic_kernel(void)
127{
128 update_cpu_boot_status(CPU_PANIC_KERNEL);
129 cpu_park_loop();
130}
131
132/*
133 * If a secondary CPU enters the kernel but fails to come online,
134 * (e.g. due to mismatched features), and cannot exit the kernel,
135 * we increment cpus_stuck_in_kernel and leave the CPU in a
136 * quiesecent loop within the kernel text. The memory containing
137 * this loop must not be re-used for anything else as the 'stuck'
138 * core is executing it.
139 *
140 * This function is used to inhibit features like kexec and hibernate.
141 */
142bool cpus_are_stuck_in_kernel(void);
143
144extern void crash_smp_send_stop(void);
145extern bool smp_crash_stop_failed(void);
146extern void panic_smp_self_stop(void);
147
148#endif /* ifndef __ASSEMBLY__ */
149
150#endif /* ifndef __ASM_SMP_H */
1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Copyright (C) 2012 ARM Ltd.
4 */
5#ifndef __ASM_SMP_H
6#define __ASM_SMP_H
7
8#include <linux/const.h>
9
10/* Values for secondary_data.status */
11#define CPU_STUCK_REASON_SHIFT (8)
12#define CPU_BOOT_STATUS_MASK ((UL(1) << CPU_STUCK_REASON_SHIFT) - 1)
13
14#define CPU_MMU_OFF (-1)
15#define CPU_BOOT_SUCCESS (0)
16/* The cpu invoked ops->cpu_die, synchronise it with cpu_kill */
17#define CPU_KILL_ME (1)
18/* The cpu couldn't die gracefully and is looping in the kernel */
19#define CPU_STUCK_IN_KERNEL (2)
20/* Fatal system error detected by secondary CPU, crash the system */
21#define CPU_PANIC_KERNEL (3)
22
23#define CPU_STUCK_REASON_52_BIT_VA (UL(1) << CPU_STUCK_REASON_SHIFT)
24#define CPU_STUCK_REASON_NO_GRAN (UL(2) << CPU_STUCK_REASON_SHIFT)
25
26#ifndef __ASSEMBLY__
27
28#include <asm/percpu.h>
29
30#include <linux/threads.h>
31#include <linux/cpumask.h>
32#include <linux/thread_info.h>
33
34DECLARE_PER_CPU_READ_MOSTLY(int, cpu_number);
35
36/*
37 * We don't use this_cpu_read(cpu_number) as that has implicit writes to
38 * preempt_count, and associated (compiler) barriers, that we'd like to avoid
39 * the expense of. If we're preemptible, the value can be stale at use anyway.
40 * And we can't use this_cpu_ptr() either, as that winds up recursing back
41 * here under CONFIG_DEBUG_PREEMPT=y.
42 */
43#define raw_smp_processor_id() (*raw_cpu_ptr(&cpu_number))
44
45/*
46 * Logical CPU mapping.
47 */
48extern u64 __cpu_logical_map[NR_CPUS];
49extern u64 cpu_logical_map(unsigned int cpu);
50
51static inline void set_cpu_logical_map(unsigned int cpu, u64 hwid)
52{
53 __cpu_logical_map[cpu] = hwid;
54}
55
56struct seq_file;
57
58/*
59 * Discover the set of possible CPUs and determine their
60 * SMP operations.
61 */
62extern void smp_init_cpus(void);
63
64/*
65 * Register IPI interrupts with the arch SMP code
66 */
67extern void set_smp_ipi_range(int ipi_base, int nr_ipi);
68
69/*
70 * Called from the secondary holding pen, this is the secondary CPU entry point.
71 */
72asmlinkage void secondary_start_kernel(void);
73
74/*
75 * Initial data for bringing up a secondary CPU.
76 * @status - Result passed back from the secondary CPU to
77 * indicate failure.
78 */
79struct secondary_data {
80 struct task_struct *task;
81 long status;
82};
83
84extern struct secondary_data secondary_data;
85extern long __early_cpu_boot_status;
86extern void secondary_entry(void);
87
88extern void arch_send_call_function_single_ipi(int cpu);
89extern void arch_send_call_function_ipi_mask(const struct cpumask *mask);
90
91#ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL
92extern void arch_send_wakeup_ipi_mask(const struct cpumask *mask);
93#else
94static inline void arch_send_wakeup_ipi_mask(const struct cpumask *mask)
95{
96 BUILD_BUG();
97}
98#endif
99
100extern int __cpu_disable(void);
101
102extern void __cpu_die(unsigned int cpu);
103extern void cpu_die(void);
104extern void cpu_die_early(void);
105
106static inline void cpu_park_loop(void)
107{
108 for (;;) {
109 wfe();
110 wfi();
111 }
112}
113
114static inline void update_cpu_boot_status(int val)
115{
116 WRITE_ONCE(secondary_data.status, val);
117 /* Ensure the visibility of the status update */
118 dsb(ishst);
119}
120
121/*
122 * The calling secondary CPU has detected serious configuration mismatch,
123 * which calls for a kernel panic. Update the boot status and park the calling
124 * CPU.
125 */
126static inline void cpu_panic_kernel(void)
127{
128 update_cpu_boot_status(CPU_PANIC_KERNEL);
129 cpu_park_loop();
130}
131
132/*
133 * If a secondary CPU enters the kernel but fails to come online,
134 * (e.g. due to mismatched features), and cannot exit the kernel,
135 * we increment cpus_stuck_in_kernel and leave the CPU in a
136 * quiesecent loop within the kernel text. The memory containing
137 * this loop must not be re-used for anything else as the 'stuck'
138 * core is executing it.
139 *
140 * This function is used to inhibit features like kexec and hibernate.
141 */
142bool cpus_are_stuck_in_kernel(void);
143
144extern void crash_smp_send_stop(void);
145extern bool smp_crash_stop_failed(void);
146extern void panic_smp_self_stop(void);
147
148#endif /* ifndef __ASSEMBLY__ */
149
150#endif /* ifndef __ASM_SMP_H */