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