include/linux/cacheinfo.h

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