arch/arm64/include/asm/smp.h

   1 /*
   2  * Copyright (C) 2012 ARM Ltd.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15  */
  16 #ifndef __ASM_SMP_H
  17 #define __ASM_SMP_H
  18
  19 /* Values for secondary_data.status */
  20
  21 #define CPU_MMU_OFF             (-1)
  22 #define CPU_BOOT_SUCCESS        (0)
  23 /* The cpu invoked ops->cpu_die, synchronise it with cpu_kill */
  24 #define CPU_KILL_ME             (1)
  25 /* The cpu couldn't die gracefully and is looping in the kernel */
  26 #define CPU_STUCK_IN_KERNEL     (2)
  27 /* Fatal system error detected by secondary CPU, crash the system */
  28 #define CPU_PANIC_KERNEL        (3)
  29
  30 #ifndef __ASSEMBLY__
  31
  32 #include <linux/threads.h>
  33 #include <linux/cpumask.h>
  34 #include <linux/thread_info.h>
  35
  36 #define raw_smp_processor_id() (current_thread_info()->cpu)
  37
  38 struct seq_file;
  39
  40 /*
  41  * generate IPI list text
  42  */
  43 extern void show_ipi_list(struct seq_file *p, int prec);
  44
  45 /*
  46  * Called from C code, this handles an IPI.
  47  */
  48 extern void handle_IPI(int ipinr, struct pt_regs *regs);
  49
  50 /*
  51  * Discover the set of possible CPUs and determine their
  52  * SMP operations.
  53  */
  54 extern void smp_init_cpus(void);
  55
  56 /*
  57  * Provide a function to raise an IPI cross call on CPUs in callmap.
  58  */
  59 extern void set_smp_cross_call(void (*)(const struct cpumask *, unsigned int));
  60
  61 extern void (*__smp_cross_call)(const struct cpumask *, unsigned int);
  62
  63 /*
  64  * Called from the secondary holding pen, this is the secondary CPU entry point.
  65  */
  66 asmlinkage void secondary_start_kernel(void);
  67
  68 /*
  69  * Initial data for bringing up a secondary CPU.
  70  * @stack  - sp for the secondary CPU
  71  * @status - Result passed back from the secondary CPU to
  72  *           indicate failure.
  73  */
  74 struct secondary_data {
  75         void *stack;
  76         long status;
  77 };
  78
  79 extern struct secondary_data secondary_data;
  80 extern long __early_cpu_boot_status;
  81 extern void secondary_entry(void);
  82
  83 extern void arch_send_call_function_single_ipi(int cpu);
  84 extern void arch_send_call_function_ipi_mask(const struct cpumask *mask);
  85
  86 #ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL
  87 extern void arch_send_wakeup_ipi_mask(const struct cpumask *mask);
  88 #else
  89 static inline void arch_send_wakeup_ipi_mask(const struct cpumask *mask)
  90 {
  91         BUILD_BUG();
  92 }
  93 #endif
  94
  95 extern int __cpu_disable(void);
  96
  97 extern void __cpu_die(unsigned int cpu);
  98 extern void cpu_die(void);
  99 extern void cpu_die_early(void);
 100
 101 static inline void cpu_park_loop(void)
 102 {
 103         for (;;) {
 104                 wfe();
 105                 wfi();
 106         }
 107 }
 108
 109 static inline void update_cpu_boot_status(int val)
 110 {
 111         WRITE_ONCE(secondary_data.status, val);
 112         /* Ensure the visibility of the status update */
 113         dsb(ishst);
 114 }
 115
 116 /*
 117  * The calling secondary CPU has detected serious configuration mismatch,
 118  * which calls for a kernel panic. Update the boot status and park the calling
 119  * CPU.
 120  */
 121 static inline void cpu_panic_kernel(void)
 122 {
 123         update_cpu_boot_status(CPU_PANIC_KERNEL);
 124         cpu_park_loop();
 125 }
 126
 127 #endif /* ifndef __ASSEMBLY__ */
 128
 129 #endif /* ifndef __ASM_SMP_H */