xref: /linux/include/linux/cacheinfo.h (revision e1b6705b)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_CACHEINFO_H
3 #define _LINUX_CACHEINFO_H
4 
5 #include <linux/bitops.h>
6 #include <linux/cpuhplock.h>
7 #include <linux/cpumask_types.h>
8 #include <linux/smp.h>
9 
10 struct device_node;
11 struct attribute;
12 
13 enum cache_type {
14 	CACHE_TYPE_NOCACHE = 0,
15 	CACHE_TYPE_INST = BIT(0),
16 	CACHE_TYPE_DATA = BIT(1),
17 	CACHE_TYPE_SEPARATE = CACHE_TYPE_INST | CACHE_TYPE_DATA,
18 	CACHE_TYPE_UNIFIED = BIT(2),
19 };
20 
21 extern unsigned int coherency_max_size;
22 
23 /**
24  * struct cacheinfo - represent a cache leaf node
25  * @id: This cache's id. It is unique among caches with the same (type, level).
26  * @type: type of the cache - data, inst or unified
27  * @level: represents the hierarchy in the multi-level cache
28  * @coherency_line_size: size of each cache line usually representing
29  *	the minimum amount of data that gets transferred from memory
30  * @number_of_sets: total number of sets, a set is a collection of cache
31  *	lines sharing the same index
32  * @ways_of_associativity: number of ways in which a particular memory
33  *	block can be placed in the cache
34  * @physical_line_partition: number of physical cache lines sharing the
35  *	same cachetag
36  * @size: Total size of the cache
37  * @shared_cpu_map: logical cpumask representing all the cpus sharing
38  *	this cache node
39  * @attributes: bitfield representing various cache attributes
40  * @fw_token: Unique value used to determine if different cacheinfo
41  *	structures represent a single hardware cache instance.
42  * @disable_sysfs: indicates whether this node is visible to the user via
43  *	sysfs or not
44  * @priv: pointer to any private data structure specific to particular
45  *	cache design
46  *
47  * While @of_node, @disable_sysfs and @priv are used for internal book
48  * keeping, the remaining members form the core properties of the cache
49  */
50 struct cacheinfo {
51 	unsigned int id;
52 	enum cache_type type;
53 	unsigned int level;
54 	unsigned int coherency_line_size;
55 	unsigned int number_of_sets;
56 	unsigned int ways_of_associativity;
57 	unsigned int physical_line_partition;
58 	unsigned int size;
59 	cpumask_t shared_cpu_map;
60 	unsigned int attributes;
61 #define CACHE_WRITE_THROUGH	BIT(0)
62 #define CACHE_WRITE_BACK	BIT(1)
63 #define CACHE_WRITE_POLICY_MASK		\
64 	(CACHE_WRITE_THROUGH | CACHE_WRITE_BACK)
65 #define CACHE_READ_ALLOCATE	BIT(2)
66 #define CACHE_WRITE_ALLOCATE	BIT(3)
67 #define CACHE_ALLOCATE_POLICY_MASK	\
68 	(CACHE_READ_ALLOCATE | CACHE_WRITE_ALLOCATE)
69 #define CACHE_ID		BIT(4)
70 	void *fw_token;
71 	bool disable_sysfs;
72 	void *priv;
73 };
74 
75 struct cpu_cacheinfo {
76 	struct cacheinfo *info_list;
77 	unsigned int per_cpu_data_slice_size;
78 	unsigned int num_levels;
79 	unsigned int num_leaves;
80 	bool cpu_map_populated;
81 	bool early_ci_levels;
82 };
83 
84 struct cpu_cacheinfo *get_cpu_cacheinfo(unsigned int cpu);
85 int early_cache_level(unsigned int cpu);
86 int init_cache_level(unsigned int cpu);
87 int init_of_cache_level(unsigned int cpu);
88 int populate_cache_leaves(unsigned int cpu);
89 int cache_setup_acpi(unsigned int cpu);
90 bool last_level_cache_is_valid(unsigned int cpu);
91 bool last_level_cache_is_shared(unsigned int cpu_x, unsigned int cpu_y);
92 int fetch_cache_info(unsigned int cpu);
93 int detect_cache_attributes(unsigned int cpu);
94 #ifndef CONFIG_ACPI_PPTT
95 /*
96  * acpi_get_cache_info() is only called on ACPI enabled
97  * platforms using the PPTT for topology. This means that if
98  * the platform supports other firmware configuration methods
99  * we need to stub out the call when ACPI is disabled.
100  * ACPI enabled platforms not using PPTT won't be making calls
101  * to this function so we need not worry about them.
102  */
103 static inline
acpi_get_cache_info(unsigned int cpu,unsigned int * levels,unsigned int * split_levels)104 int acpi_get_cache_info(unsigned int cpu,
105 			unsigned int *levels, unsigned int *split_levels)
106 {
107 	return -ENOENT;
108 }
109 #else
110 int acpi_get_cache_info(unsigned int cpu,
111 			unsigned int *levels, unsigned int *split_levels);
112 #endif
113 
114 const struct attribute_group *cache_get_priv_group(struct cacheinfo *this_leaf);
115 
116 /*
117  * Get the cacheinfo structure for the cache associated with @cpu at
118  * level @level.
119  * cpuhp lock must be held.
120  */
get_cpu_cacheinfo_level(int cpu,int level)121 static inline struct cacheinfo *get_cpu_cacheinfo_level(int cpu, int level)
122 {
123 	struct cpu_cacheinfo *ci = get_cpu_cacheinfo(cpu);
124 	int i;
125 
126 	lockdep_assert_cpus_held();
127 
128 	for (i = 0; i < ci->num_leaves; i++) {
129 		if (ci->info_list[i].level == level) {
130 			if (ci->info_list[i].attributes & CACHE_ID)
131 				return &ci->info_list[i];
132 			return NULL;
133 		}
134 	}
135 
136 	return NULL;
137 }
138 
139 /*
140  * Get the id of the cache associated with @cpu at level @level.
141  * cpuhp lock must be held.
142  */
get_cpu_cacheinfo_id(int cpu,int level)143 static inline int get_cpu_cacheinfo_id(int cpu, int level)
144 {
145 	struct cacheinfo *ci = get_cpu_cacheinfo_level(cpu, level);
146 
147 	return ci ? ci->id : -1;
148 }
149 
150 #ifdef CONFIG_ARM64
151 #define use_arch_cache_info()	(true)
152 #else
153 #define use_arch_cache_info()	(false)
154 #endif
155 
156 #ifndef CONFIG_ARCH_HAS_CPU_CACHE_ALIASING
157 #define cpu_dcache_is_aliasing()	false
158 #else
159 #include <asm/cachetype.h>
160 #endif
161 
162 #endif /* _LINUX_CACHEINFO_H */
163