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/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 /**
  21  * struct cacheinfo - represent a cache leaf node
  22  * @id: This cache's id. It is unique among caches with the same (type, level).
  23  * @type: type of the cache - data, inst or unified
  24  * @level: represents the hierarchy in the multi-level cache
  25  * @coherency_line_size: size of each cache line usually representing
  26  *      the minimum amount of data that gets transferred from memory
  27  * @number_of_sets: total number of sets, a set is a collection of cache
  28  *      lines sharing the same index
  29  * @ways_of_associativity: number of ways in which a particular memory
  30  *      block can be placed in the cache
  31  * @physical_line_partition: number of physical cache lines sharing the
  32  *      same cachetag
  33  * @size: Total size of the cache
  34  * @shared_cpu_map: logical cpumask representing all the cpus sharing
  35  *      this cache node
  36  * @attributes: bitfield representing various cache attributes
  37  * @of_node: if devicetree is used, this represents either the cpu node in
  38  *      case there's no explicit cache node or the cache node itself in the
  39  *      device tree
  40  * @disable_sysfs: indicates whether this node is visible to the user via
  41  *      sysfs or not
  42  * @priv: pointer to any private data structure specific to particular
  43  *      cache design
  44  *
  45  * While @of_node, @disable_sysfs and @priv are used for internal book
  46  * keeping, the remaining members form the core properties of the cache
  47  */
  48 struct cacheinfo {
  49         unsigned int id;
  50         enum cache_type type;
  51         unsigned int level;
  52         unsigned int coherency_line_size;
  53         unsigned int number_of_sets;
  54         unsigned int ways_of_associativity;
  55         unsigned int physical_line_partition;
  56         unsigned int size;
  57         cpumask_t shared_cpu_map;
  58         unsigned int attributes;
  59 #define CACHE_WRITE_THROUGH     BIT(0)
  60 #define CACHE_WRITE_BACK        BIT(1)
  61 #define CACHE_WRITE_POLICY_MASK         \
  62         (CACHE_WRITE_THROUGH | CACHE_WRITE_BACK)
  63 #define CACHE_READ_ALLOCATE     BIT(2)
  64 #define CACHE_WRITE_ALLOCATE    BIT(3)
  65 #define CACHE_ALLOCATE_POLICY_MASK      \
  66         (CACHE_READ_ALLOCATE | CACHE_WRITE_ALLOCATE)
  67 #define CACHE_ID                BIT(4)
  68
  69         struct device_node *of_node;
  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 /*
  82  * Helpers to make sure "func" is executed on the cpu whose cache
  83  * attributes are being detected
  84  */
  85 #define DEFINE_SMP_CALL_CACHE_FUNCTION(func)                    \
  86 static inline void _##func(void *ret)                           \
  87 {                                                               \
  88         int cpu = smp_processor_id();                           \
  89         *(int *)ret = __##func(cpu);                            \
  90 }                                                               \
  91                                                                 \
  92 int func(unsigned int cpu)                                      \
  93 {                                                               \
  94         int ret;                                                \
  95         smp_call_function_single(cpu, _##func, &ret, true);     \
  96         return ret;                                             \
  97 }
  98
  99 struct cpu_cacheinfo *get_cpu_cacheinfo(unsigned int cpu);
 100 int init_cache_level(unsigned int cpu);
 101 int populate_cache_leaves(unsigned int cpu);
 102
 103 const struct attribute_group *cache_get_priv_group(struct cacheinfo *this_leaf);
 104
 105 #endif /* _LINUX_CACHEINFO_H */