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 <linux/threads.h> 29 #include <linux/cpumask.h> 30 #include <linux/thread_info.h> 31 32 #define raw_smp_processor_id() (current_thread_info()->cpu) 33 34 /* 35 * Logical CPU mapping. 36 */ 37 extern u64 __cpu_logical_map[NR_CPUS]; 38 extern u64 cpu_logical_map(unsigned int cpu); 39 set_cpu_logical_map(unsigned int cpu,u64 hwid)40 static inline void set_cpu_logical_map(unsigned int cpu, u64 hwid) 41 { 42 __cpu_logical_map[cpu] = hwid; 43 } 44 45 struct seq_file; 46 47 /* 48 * Discover the set of possible CPUs and determine their 49 * SMP operations. 50 */ 51 extern void smp_init_cpus(void); 52 53 /* 54 * Register IPI interrupts with the arch SMP code 55 */ 56 extern void set_smp_ipi_range(int ipi_base, int nr_ipi); 57 58 /* 59 * Called from the secondary holding pen, this is the secondary CPU entry point. 60 */ 61 asmlinkage void secondary_start_kernel(void); 62 63 /* 64 * Initial data for bringing up a secondary CPU. 65 * @status - Result passed back from the secondary CPU to 66 * indicate failure. 67 */ 68 struct secondary_data { 69 struct task_struct *task; 70 long status; 71 }; 72 73 extern struct secondary_data secondary_data; 74 extern long __early_cpu_boot_status; 75 extern void secondary_entry(void); 76 77 extern void arch_send_call_function_single_ipi(int cpu); 78 extern void arch_send_call_function_ipi_mask(const struct cpumask *mask); 79 80 #ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL 81 extern void arch_send_wakeup_ipi(unsigned int cpu); 82 #else arch_send_wakeup_ipi(unsigned int cpu)83 static inline void arch_send_wakeup_ipi(unsigned int cpu) 84 { 85 BUILD_BUG(); 86 } 87 #endif 88 89 extern int __cpu_disable(void); 90 __cpu_die(unsigned int cpu)91 static inline void __cpu_die(unsigned int cpu) { } 92 extern void __noreturn cpu_die(void); 93 extern void __noreturn cpu_die_early(void); 94 cpu_park_loop(void)95 static inline void __noreturn cpu_park_loop(void) 96 { 97 for (;;) { 98 wfe(); 99 wfi(); 100 } 101 } 102 update_cpu_boot_status(int val)103 static inline void update_cpu_boot_status(int val) 104 { 105 WRITE_ONCE(secondary_data.status, val); 106 /* Ensure the visibility of the status update */ 107 dsb(ishst); 108 } 109 110 /* 111 * The calling secondary CPU has detected serious configuration mismatch, 112 * which calls for a kernel panic. Update the boot status and park the calling 113 * CPU. 114 */ cpu_panic_kernel(void)115 static inline void __noreturn cpu_panic_kernel(void) 116 { 117 update_cpu_boot_status(CPU_PANIC_KERNEL); 118 cpu_park_loop(); 119 } 120 121 /* 122 * If a secondary CPU enters the kernel but fails to come online, 123 * (e.g. due to mismatched features), and cannot exit the kernel, 124 * we increment cpus_stuck_in_kernel and leave the CPU in a 125 * quiesecent loop within the kernel text. The memory containing 126 * this loop must not be re-used for anything else as the 'stuck' 127 * core is executing it. 128 * 129 * This function is used to inhibit features like kexec and hibernate. 130 */ 131 bool cpus_are_stuck_in_kernel(void); 132 133 extern void crash_smp_send_stop(void); 134 extern bool smp_crash_stop_failed(void); 135 136 #endif /* ifndef __ASSEMBLY__ */ 137 138 #endif /* ifndef __ASM_SMP_H */ 139