1 /* SPDX-License-Identifier: GPL-2.0-only */
3 * Copyright (C) 2012 ARM Ltd.
8 #include <linux/const.h>
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)
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)
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)
28 #include <asm/percpu.h>
30 #include <linux/threads.h>
31 #include <linux/cpumask.h>
32 #include <linux/thread_info.h>
33 #include <asm/pointer_auth.h>
35 DECLARE_PER_CPU_READ_MOSTLY(int, cpu_number);
38 * We don't use this_cpu_read(cpu_number) as that has implicit writes to
39 * preempt_count, and associated (compiler) barriers, that we'd like to avoid
40 * the expense of. If we're preemptible, the value can be stale at use anyway.
41 * And we can't use this_cpu_ptr() either, as that winds up recursing back
42 * here under CONFIG_DEBUG_PREEMPT=y.
44 #define raw_smp_processor_id() (*raw_cpu_ptr(&cpu_number))
47 * Logical CPU mapping.
49 extern u64 __cpu_logical_map[NR_CPUS];
50 #define cpu_logical_map(cpu) __cpu_logical_map[cpu]
55 * generate IPI list text
57 extern void show_ipi_list(struct seq_file *p, int prec);
60 * Called from C code, this handles an IPI.
62 extern void handle_IPI(int ipinr, struct pt_regs *regs);
65 * Discover the set of possible CPUs and determine their
68 extern void smp_init_cpus(void);
71 * Provide a function to raise an IPI cross call on CPUs in callmap.
73 extern void set_smp_cross_call(void (*)(const struct cpumask *, unsigned int));
75 extern void (*__smp_cross_call)(const struct cpumask *, unsigned int);
78 * Called from the secondary holding pen, this is the secondary CPU entry point.
80 asmlinkage void secondary_start_kernel(void);
83 * Initial data for bringing up a secondary CPU.
84 * @stack - sp for the secondary CPU
85 * @status - Result passed back from the secondary CPU to
88 struct secondary_data {
90 struct task_struct *task;
94 extern struct secondary_data secondary_data;
95 extern long __early_cpu_boot_status;
96 extern void secondary_entry(void);
98 extern void arch_send_call_function_single_ipi(int cpu);
99 extern void arch_send_call_function_ipi_mask(const struct cpumask *mask);
101 #ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL
102 extern void arch_send_wakeup_ipi_mask(const struct cpumask *mask);
104 static inline void arch_send_wakeup_ipi_mask(const struct cpumask *mask)
110 extern int __cpu_disable(void);
112 extern void __cpu_die(unsigned int cpu);
113 extern void cpu_die(void);
114 extern void cpu_die_early(void);
116 static inline void cpu_park_loop(void)
124 static inline void update_cpu_boot_status(int val)
126 WRITE_ONCE(secondary_data.status, val);
127 /* Ensure the visibility of the status update */
132 * The calling secondary CPU has detected serious configuration mismatch,
133 * which calls for a kernel panic. Update the boot status and park the calling
136 static inline void cpu_panic_kernel(void)
138 update_cpu_boot_status(CPU_PANIC_KERNEL);
143 * If a secondary CPU enters the kernel but fails to come online,
144 * (e.g. due to mismatched features), and cannot exit the kernel,
145 * we increment cpus_stuck_in_kernel and leave the CPU in a
146 * quiesecent loop within the kernel text. The memory containing
147 * this loop must not be re-used for anything else as the 'stuck'
148 * core is executing it.
150 * This function is used to inhibit features like kexec and hibernate.
152 bool cpus_are_stuck_in_kernel(void);
154 extern void crash_smp_send_stop(void);
155 extern bool smp_crash_stop_failed(void);
157 #endif /* ifndef __ASSEMBLY__ */
159 #endif /* ifndef __ASM_SMP_H */