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 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 enum ipi_msg_type { 54 IPI_RESCHEDULE, 55 IPI_CALL_FUNC, 56 IPI_CPU_STOP, 57 IPI_CPU_STOP_NMI, 58 IPI_TIMER, 59 IPI_IRQ_WORK, 60 NR_IPI, 61 /* 62 * Any enum >= NR_IPI and < MAX_IPI is special and not tracable 63 * with trace_ipi_* 64 */ 65 IPI_CPU_BACKTRACE = NR_IPI, 66 IPI_KGDB_ROUNDUP, 67 MAX_IPI 68 }; 69 70 /* 71 * Register IPI interrupts with the arch SMP code 72 */ 73 extern void set_smp_ipi_range_percpu(int ipi_base, int nr_ipi, int ncpus); 74 75 static inline void set_smp_ipi_range(int ipi_base, int n) 76 { 77 set_smp_ipi_range_percpu(ipi_base, n, 0); 78 } 79 80 /* 81 * Called from the secondary holding pen, this is the secondary CPU entry point. 82 */ 83 asmlinkage void secondary_start_kernel(void); 84 85 /* 86 * Initial data for bringing up a secondary CPU. 87 * @status - Result passed back from the secondary CPU to 88 * indicate failure. 89 */ 90 struct secondary_data { 91 struct task_struct *task; 92 long status; 93 }; 94 95 extern struct secondary_data secondary_data; 96 extern long __early_cpu_boot_status; 97 extern void secondary_entry(void); 98 99 extern void arch_send_call_function_single_ipi(int cpu); 100 extern void arch_send_call_function_ipi_mask(const struct cpumask *mask); 101 102 #ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL 103 extern void arch_send_wakeup_ipi(unsigned int cpu); 104 #else 105 static inline void arch_send_wakeup_ipi(unsigned int cpu) 106 { 107 BUILD_BUG(); 108 } 109 #endif 110 111 extern int __cpu_disable(void); 112 113 static inline void __cpu_die(unsigned int cpu) { } 114 extern void __noreturn cpu_die(void); 115 extern void __noreturn cpu_die_early(void); 116 117 static inline void __noreturn cpu_park_loop(void) 118 { 119 for (;;) { 120 wfe(); 121 wfi(); 122 } 123 } 124 125 static inline void update_cpu_boot_status(int val) 126 { 127 WRITE_ONCE(secondary_data.status, val); 128 /* Ensure the visibility of the status update */ 129 dsb(ishst); 130 } 131 132 /* 133 * The calling secondary CPU has detected serious configuration mismatch, 134 * which calls for a kernel panic. Update the boot status and park the calling 135 * CPU. 136 */ 137 static inline void __noreturn cpu_panic_kernel(void) 138 { 139 update_cpu_boot_status(CPU_PANIC_KERNEL); 140 cpu_park_loop(); 141 } 142 143 /* 144 * If a secondary CPU enters the kernel but fails to come online, 145 * (e.g. due to mismatched features), and cannot exit the kernel, 146 * we increment cpus_stuck_in_kernel and leave the CPU in a 147 * quiesecent loop within the kernel text. The memory containing 148 * this loop must not be re-used for anything else as the 'stuck' 149 * core is executing it. 150 * 151 * This function is used to inhibit features like kexec and hibernate. 152 */ 153 bool cpus_are_stuck_in_kernel(void); 154 155 extern void crash_smp_send_stop(void); 156 extern bool smp_crash_stop_failed(void); 157 158 #endif /* ifndef __ASSEMBLY__ */ 159 160 #endif /* ifndef __ASM_SMP_H */ 161