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/cpu.h>
7 #include <linux/cpumask.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 num_levels;
78 	unsigned int num_leaves;
79 	bool cpu_map_populated;
80 };
81 
82 /*
83  * Helpers to make sure "func" is executed on the cpu whose cache
84  * attributes are being detected
85  */
86 #define DEFINE_SMP_CALL_CACHE_FUNCTION(func)			\
87 static inline void _##func(void *ret)				\
88 {								\
89 	int cpu = smp_processor_id();				\
90 	*(int *)ret = __##func(cpu);				\
91 }								\
92 								\
93 int func(unsigned int cpu)					\
94 {								\
95 	int ret;						\
96 	smp_call_function_single(cpu, _##func, &ret, true);	\
97 	return ret;						\
98 }
99 
100 struct cpu_cacheinfo *get_cpu_cacheinfo(unsigned int cpu);
101 int init_cache_level(unsigned int cpu);
102 int populate_cache_leaves(unsigned int cpu);
103 int cache_setup_acpi(unsigned int cpu);
104 #ifndef CONFIG_ACPI_PPTT
105 /*
106  * acpi_find_last_cache_level is only called on ACPI enabled
107  * platforms using the PPTT for topology. This means that if
108  * the platform supports other firmware configuration methods
109  * we need to stub out the call when ACPI is disabled.
110  * ACPI enabled platforms not using PPTT won't be making calls
111  * to this function so we need not worry about them.
112  */
acpi_find_last_cache_level(unsigned int cpu)113 static inline int acpi_find_last_cache_level(unsigned int cpu)
114 {
115 	return 0;
116 }
117 #else
118 int acpi_find_last_cache_level(unsigned int cpu);
119 #endif
120 
121 const struct attribute_group *cache_get_priv_group(struct cacheinfo *this_leaf);
122 
123 /*
124  * Get the id of the cache associated with @cpu at level @level.
125  * cpuhp lock must be held.
126  */
get_cpu_cacheinfo_id(int cpu,int level)127 static inline int get_cpu_cacheinfo_id(int cpu, int level)
128 {
129 	struct cpu_cacheinfo *ci = get_cpu_cacheinfo(cpu);
130 	int i;
131 
132 	for (i = 0; i < ci->num_leaves; i++) {
133 		if (ci->info_list[i].level == level) {
134 			if (ci->info_list[i].attributes & CACHE_ID)
135 				return ci->info_list[i].id;
136 			return -1;
137 		}
138 	}
139 
140 	return -1;
141 }
142 
143 #endif /* _LINUX_CACHEINFO_H */
144