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 };
80
81 struct cpu_cacheinfo *get_cpu_cacheinfo(unsigned int cpu);
82 int init_cache_level(unsigned int cpu);
83 int init_of_cache_level(unsigned int cpu);
84 int populate_cache_leaves(unsigned int cpu);
85 int cache_setup_acpi(unsigned int cpu);
86 bool last_level_cache_is_valid(unsigned int cpu);
87 bool last_level_cache_is_shared(unsigned int cpu_x, unsigned int cpu_y);
88 int fetch_cache_info(unsigned int cpu);
89 int detect_cache_attributes(unsigned int cpu);
90 #ifndef CONFIG_ACPI_PPTT
91 /*
92 * acpi_get_cache_info() is only called on ACPI enabled
93 * platforms using the PPTT for topology. This means that if
94 * the platform supports other firmware configuration methods
95 * we need to stub out the call when ACPI is disabled.
96 * ACPI enabled platforms not using PPTT won't be making calls
97 * to this function so we need not worry about them.
98 */
99 static inline
acpi_get_cache_info(unsigned int cpu,unsigned int * levels,unsigned int * split_levels)100 int acpi_get_cache_info(unsigned int cpu,
101 unsigned int *levels, unsigned int *split_levels)
102 {
103 return -ENOENT;
104 }
105 #else
106 int acpi_get_cache_info(unsigned int cpu,
107 unsigned int *levels, unsigned int *split_levels);
108 #endif
109
110 const struct attribute_group *cache_get_priv_group(struct cacheinfo *this_leaf);
111
112 /*
113 * Get the id of the cache associated with @cpu at level @level.
114 * cpuhp lock must be held.
115 */
get_cpu_cacheinfo_id(int cpu,int level)116 static inline int get_cpu_cacheinfo_id(int cpu, int level)
117 {
118 struct cpu_cacheinfo *ci = get_cpu_cacheinfo(cpu);
119 int i;
120
121 for (i = 0; i < ci->num_leaves; i++) {
122 if (ci->info_list[i].level == level) {
123 if (ci->info_list[i].attributes & CACHE_ID)
124 return ci->info_list[i].id;
125 return -1;
126 }
127 }
128
129 return -1;
130 }
131
132 #endif /* _LINUX_CACHEINFO_H */
133