xref: /openbmc/linux/arch/s390/include/asm/smp.h (revision e285d5bf)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  *    Copyright IBM Corp. 1999, 2012
4  *    Author(s): Denis Joseph Barrow,
5  *		 Martin Schwidefsky <schwidefsky@de.ibm.com>,
6  *		 Heiko Carstens <heiko.carstens@de.ibm.com>,
7  */
8 #ifndef __ASM_SMP_H
9 #define __ASM_SMP_H
10 
11 #include <asm/sigp.h>
12 
13 #ifdef CONFIG_SMP
14 
15 #include <asm/lowcore.h>
16 
17 #define raw_smp_processor_id()	(S390_lowcore.cpu_nr)
18 
19 extern struct mutex smp_cpu_state_mutex;
20 extern unsigned int smp_cpu_mt_shift;
21 extern unsigned int smp_cpu_mtid;
22 extern __vector128 __initdata boot_cpu_vector_save_area[__NUM_VXRS];
23 
24 extern int __cpu_up(unsigned int cpu, struct task_struct *tidle);
25 
26 extern void arch_send_call_function_single_ipi(int cpu);
27 extern void arch_send_call_function_ipi_mask(const struct cpumask *mask);
28 
29 extern void smp_call_online_cpu(void (*func)(void *), void *);
30 extern void smp_call_ipl_cpu(void (*func)(void *), void *);
31 extern void smp_emergency_stop(void);
32 
33 extern int smp_find_processor_id(u16 address);
34 extern int smp_store_status(int cpu);
35 extern void smp_save_dump_cpus(void);
36 extern int smp_vcpu_scheduled(int cpu);
37 extern void smp_yield_cpu(int cpu);
38 extern void smp_cpu_set_polarization(int cpu, int val);
39 extern int smp_cpu_get_polarization(int cpu);
40 extern void smp_fill_possible_mask(void);
41 extern void smp_detect_cpus(void);
42 
43 #else /* CONFIG_SMP */
44 
45 #define smp_cpu_mtid	0
46 
47 static inline void smp_call_ipl_cpu(void (*func)(void *), void *data)
48 {
49 	func(data);
50 }
51 
52 static inline void smp_call_online_cpu(void (*func)(void *), void *data)
53 {
54 	func(data);
55 }
56 
57 static inline void smp_emergency_stop(void)
58 {
59 }
60 
61 static inline int smp_find_processor_id(u16 address) { return 0; }
62 static inline int smp_store_status(int cpu) { return 0; }
63 static inline int smp_vcpu_scheduled(int cpu) { return 1; }
64 static inline void smp_yield_cpu(int cpu) { }
65 static inline void smp_fill_possible_mask(void) { }
66 static inline void smp_detect_cpus(void) { }
67 
68 #endif /* CONFIG_SMP */
69 
70 static inline void smp_stop_cpu(void)
71 {
72 	u16 pcpu = stap();
73 
74 	for (;;) {
75 		__pcpu_sigp(pcpu, SIGP_STOP, 0, NULL);
76 		cpu_relax();
77 	}
78 }
79 
80 /* Return thread 0 CPU number as base CPU */
81 static inline int smp_get_base_cpu(int cpu)
82 {
83 	return cpu - (cpu % (smp_cpu_mtid + 1));
84 }
85 
86 #ifdef CONFIG_HOTPLUG_CPU
87 extern int smp_rescan_cpus(void);
88 extern void __noreturn cpu_die(void);
89 extern void __cpu_die(unsigned int cpu);
90 extern int __cpu_disable(void);
91 #else
92 static inline int smp_rescan_cpus(void) { return 0; }
93 static inline void cpu_die(void) { }
94 #endif
95 
96 #endif /* __ASM_SMP_H */
97