1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * ARM64 cacheinfo support
4 *
5 * Copyright (C) 2015 ARM Ltd.
6 * All Rights Reserved
7 */
8
9 #include <linux/acpi.h>
10 #include <linux/cacheinfo.h>
11 #include <linux/of.h>
12
13 #define MAX_CACHE_LEVEL 7 /* Max 7 level supported */
14
15 int cache_line_size(void)
16 {
17 if (coherency_max_size != 0)
18 return coherency_max_size;
19
20 return cache_line_size_of_cpu();
21 }
22 EXPORT_SYMBOL_GPL(cache_line_size);
23
24 static inline enum cache_type get_cache_type(int level)
25 {
26 u64 clidr;
27
28 if (level > MAX_CACHE_LEVEL)
29 return CACHE_TYPE_NOCACHE;
30 clidr = read_sysreg(clidr_el1);
31 return CLIDR_CTYPE(clidr, level);
32 }
33
34 static void ci_leaf_init(struct cacheinfo *this_leaf,
35 enum cache_type type, unsigned int level)
36 {
37 this_leaf->level = level;
38 this_leaf->type = type;
39 }
40
41 static void detect_cache_level(unsigned int *level_p, unsigned int *leaves_p)
42 {
43 unsigned int ctype, level, leaves;
44
45 for (level = 1, leaves = 0; level <= MAX_CACHE_LEVEL; level++) {
46 ctype = get_cache_type(level);
47 if (ctype == CACHE_TYPE_NOCACHE) {
48 level--;
49 break;
50 }
51 /* Separate instruction and data caches */
52 leaves += (ctype == CACHE_TYPE_SEPARATE) ? 2 : 1;
53 }
54
55 *level_p = level;
56 *leaves_p = leaves;
57 }
58
59 int early_cache_level(unsigned int cpu)
60 {
61 struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
62
63 detect_cache_level(&this_cpu_ci->num_levels, &this_cpu_ci->num_leaves);
64
65 return 0;
66 }
67
68 int init_cache_level(unsigned int cpu)
69 {
70 unsigned int level, leaves;
71 int fw_level, ret;
72 struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
73
74 detect_cache_level(&level, &leaves);
75
76 if (acpi_disabled) {
77 fw_level = of_find_last_cache_level(cpu);
78 } else {
79 ret = acpi_get_cache_info(cpu, &fw_level, NULL);
80 if (ret < 0)
81 fw_level = 0;
82 }
83
84 if (level < fw_level) {
85 /*
86 * some external caches not specified in CLIDR_EL1
87 * the information may be available in the device tree
88 * only unified external caches are considered here
89 */
90 leaves += (fw_level - level);
91 level = fw_level;
92 }
93
94 this_cpu_ci->num_levels = level;
95 this_cpu_ci->num_leaves = leaves;
96 return 0;
97 }
98
99 int populate_cache_leaves(unsigned int cpu)
100 {
101 unsigned int level, idx;
102 enum cache_type type;
103 struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
104 struct cacheinfo *this_leaf = this_cpu_ci->info_list;
105
106 for (idx = 0, level = 1; level <= this_cpu_ci->num_levels &&
107 idx < this_cpu_ci->num_leaves; idx++, level++) {
108 type = get_cache_type(level);
109 if (type == CACHE_TYPE_SEPARATE) {
110 ci_leaf_init(this_leaf++, CACHE_TYPE_DATA, level);
111 ci_leaf_init(this_leaf++, CACHE_TYPE_INST, level);
112 } else {
113 ci_leaf_init(this_leaf++, type, level);
114 }
115 }
116 return 0;
117 }
118
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