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Diffstat (limited to 'arch/arm64/include/asm/smp.h')
-rw-r--r-- | arch/arm64/include/asm/smp.h | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/smp.h b/arch/arm64/include/asm/smp.h new file mode 100644 index 000000000..fc55f5a57 --- /dev/null +++ b/arch/arm64/include/asm/smp.h @@ -0,0 +1,150 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2012 ARM Ltd. + */ +#ifndef __ASM_SMP_H +#define __ASM_SMP_H + +#include <linux/const.h> + +/* Values for secondary_data.status */ +#define CPU_STUCK_REASON_SHIFT (8) +#define CPU_BOOT_STATUS_MASK ((UL(1) << CPU_STUCK_REASON_SHIFT) - 1) + +#define CPU_MMU_OFF (-1) +#define CPU_BOOT_SUCCESS (0) +/* The cpu invoked ops->cpu_die, synchronise it with cpu_kill */ +#define CPU_KILL_ME (1) +/* The cpu couldn't die gracefully and is looping in the kernel */ +#define CPU_STUCK_IN_KERNEL (2) +/* Fatal system error detected by secondary CPU, crash the system */ +#define CPU_PANIC_KERNEL (3) + +#define CPU_STUCK_REASON_52_BIT_VA (UL(1) << CPU_STUCK_REASON_SHIFT) +#define CPU_STUCK_REASON_NO_GRAN (UL(2) << CPU_STUCK_REASON_SHIFT) + +#ifndef __ASSEMBLY__ + +#include <asm/percpu.h> + +#include <linux/threads.h> +#include <linux/cpumask.h> +#include <linux/thread_info.h> + +DECLARE_PER_CPU_READ_MOSTLY(int, cpu_number); + +/* + * We don't use this_cpu_read(cpu_number) as that has implicit writes to + * preempt_count, and associated (compiler) barriers, that we'd like to avoid + * the expense of. If we're preemptible, the value can be stale at use anyway. + * And we can't use this_cpu_ptr() either, as that winds up recursing back + * here under CONFIG_DEBUG_PREEMPT=y. + */ +#define raw_smp_processor_id() (*raw_cpu_ptr(&cpu_number)) + +/* + * Logical CPU mapping. + */ +extern u64 __cpu_logical_map[NR_CPUS]; +extern u64 cpu_logical_map(unsigned int cpu); + +static inline void set_cpu_logical_map(unsigned int cpu, u64 hwid) +{ + __cpu_logical_map[cpu] = hwid; +} + +struct seq_file; + +/* + * Discover the set of possible CPUs and determine their + * SMP operations. + */ +extern void smp_init_cpus(void); + +/* + * Register IPI interrupts with the arch SMP code + */ +extern void set_smp_ipi_range(int ipi_base, int nr_ipi); + +/* + * Called from the secondary holding pen, this is the secondary CPU entry point. + */ +asmlinkage void secondary_start_kernel(void); + +/* + * Initial data for bringing up a secondary CPU. + * @status - Result passed back from the secondary CPU to + * indicate failure. + */ +struct secondary_data { + struct task_struct *task; + long status; +}; + +extern struct secondary_data secondary_data; +extern long __early_cpu_boot_status; +extern void secondary_entry(void); + +extern void arch_send_call_function_single_ipi(int cpu); +extern void arch_send_call_function_ipi_mask(const struct cpumask *mask); + +#ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL +extern void arch_send_wakeup_ipi_mask(const struct cpumask *mask); +#else +static inline void arch_send_wakeup_ipi_mask(const struct cpumask *mask) +{ + BUILD_BUG(); +} +#endif + +extern int __cpu_disable(void); + +extern void __cpu_die(unsigned int cpu); +extern void cpu_die(void); +extern void cpu_die_early(void); + +static inline void cpu_park_loop(void) +{ + for (;;) { + wfe(); + wfi(); + } +} + +static inline void update_cpu_boot_status(int val) +{ + WRITE_ONCE(secondary_data.status, val); + /* Ensure the visibility of the status update */ + dsb(ishst); +} + +/* + * The calling secondary CPU has detected serious configuration mismatch, + * which calls for a kernel panic. Update the boot status and park the calling + * CPU. + */ +static inline void cpu_panic_kernel(void) +{ + update_cpu_boot_status(CPU_PANIC_KERNEL); + cpu_park_loop(); +} + +/* + * If a secondary CPU enters the kernel but fails to come online, + * (e.g. due to mismatched features), and cannot exit the kernel, + * we increment cpus_stuck_in_kernel and leave the CPU in a + * quiesecent loop within the kernel text. The memory containing + * this loop must not be re-used for anything else as the 'stuck' + * core is executing it. + * + * This function is used to inhibit features like kexec and hibernate. + */ +bool cpus_are_stuck_in_kernel(void); + +extern void crash_smp_send_stop(void); +extern bool smp_crash_stop_failed(void); +extern void panic_smp_self_stop(void); + +#endif /* ifndef __ASSEMBLY__ */ + +#endif /* ifndef __ASM_SMP_H */ |