xref: /openbmc/linux/arch/arm/include/asm/smp_plat.h (revision 84d517f3)
1 /*
2  * ARM specific SMP header, this contains our implementation
3  * details.
4  */
5 #ifndef __ASMARM_SMP_PLAT_H
6 #define __ASMARM_SMP_PLAT_H
7 
8 #include <linux/cpumask.h>
9 #include <linux/err.h>
10 
11 #include <asm/cputype.h>
12 
13 /*
14  * Return true if we are running on a SMP platform
15  */
16 static inline bool is_smp(void)
17 {
18 #ifndef CONFIG_SMP
19 	return false;
20 #elif defined(CONFIG_SMP_ON_UP)
21 	extern unsigned int smp_on_up;
22 	return !!smp_on_up;
23 #else
24 	return true;
25 #endif
26 }
27 
28 /* all SMP configurations have the extended CPUID registers */
29 #ifndef CONFIG_MMU
30 #define tlb_ops_need_broadcast()	0
31 #else
32 static inline int tlb_ops_need_broadcast(void)
33 {
34 	if (!is_smp())
35 		return 0;
36 
37 	return ((read_cpuid_ext(CPUID_EXT_MMFR3) >> 12) & 0xf) < 2;
38 }
39 #endif
40 
41 #if !defined(CONFIG_SMP) || __LINUX_ARM_ARCH__ >= 7
42 #define cache_ops_need_broadcast()	0
43 #else
44 static inline int cache_ops_need_broadcast(void)
45 {
46 	if (!is_smp())
47 		return 0;
48 
49 	return ((read_cpuid_ext(CPUID_EXT_MMFR3) >> 12) & 0xf) < 1;
50 }
51 #endif
52 
53 /*
54  * Logical CPU mapping.
55  */
56 extern u32 __cpu_logical_map[];
57 #define cpu_logical_map(cpu)	__cpu_logical_map[cpu]
58 /*
59  * Retrieve logical cpu index corresponding to a given MPIDR[23:0]
60  *  - mpidr: MPIDR[23:0] to be used for the look-up
61  *
62  * Returns the cpu logical index or -EINVAL on look-up error
63  */
64 static inline int get_logical_index(u32 mpidr)
65 {
66 	int cpu;
67 	for (cpu = 0; cpu < nr_cpu_ids; cpu++)
68 		if (cpu_logical_map(cpu) == mpidr)
69 			return cpu;
70 	return -EINVAL;
71 }
72 
73 /*
74  * NOTE ! Assembly code relies on the following
75  * structure memory layout in order to carry out load
76  * multiple from its base address. For more
77  * information check arch/arm/kernel/sleep.S
78  */
79 struct mpidr_hash {
80 	u32	mask; /* used by sleep.S */
81 	u32	shift_aff[3]; /* used by sleep.S */
82 	u32	bits;
83 };
84 
85 extern struct mpidr_hash mpidr_hash;
86 
87 static inline u32 mpidr_hash_size(void)
88 {
89 	return 1 << mpidr_hash.bits;
90 }
91 
92 extern int platform_can_cpu_hotplug(void);
93 
94 #endif
95