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Diffstat (limited to 'arch/arm64/include/asm/smp.h')
| -rw-r--r-- | arch/arm64/include/asm/smp.h | 156 |
1 files changed, 156 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..f82b447bd --- /dev/null +++ b/arch/arm64/include/asm/smp.h @@ -0,0 +1,156 @@ +/* + * Copyright (C) 2012 ARM Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ +#ifndef __ASM_SMP_H +#define __ASM_SMP_H + +/* Values for secondary_data.status */ + +#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) + +#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)) + +struct seq_file; + +/* + * generate IPI list text + */ +extern void show_ipi_list(struct seq_file *p, int prec); + +/* + * Called from C code, this handles an IPI. + */ +extern void handle_IPI(int ipinr, struct pt_regs *regs); + +/* + * Discover the set of possible CPUs and determine their + * SMP operations. + */ +extern void smp_init_cpus(void); + +/* + * Provide a function to raise an IPI cross call on CPUs in callmap. + */ +extern void set_smp_cross_call(void (*)(const struct cpumask *, unsigned int)); + +extern void (*__smp_cross_call)(const struct cpumask *, unsigned int); + +/* + * 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. + * @stack - sp for the secondary CPU + * @status - Result passed back from the secondary CPU to + * indicate failure. + */ +struct secondary_data { + void *stack; + 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); + +#endif /* ifndef __ASSEMBLY__ */ + +#endif /* ifndef __ASM_SMP_H */ |