1 /*
2 * ARM64 cacheinfo support
3 *
4 * Copyright (C) 2015 ARM Ltd.
5 * All Rights Reserved
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
12 * kind, whether express or implied; without even the implied warranty
13 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 */
19
20 #include <linux/bitops.h>
21 #include <linux/cacheinfo.h>
22 #include <linux/cpu.h>
23 #include <linux/compiler.h>
24 #include <linux/of.h>
25
26 #include <asm/cachetype.h>
27 #include <asm/processor.h>
28
29 #define MAX_CACHE_LEVEL 7 /* Max 7 level supported */
30 /* Ctypen, bits[3(n - 1) + 2 : 3(n - 1)], for n = 1 to 7 */
31 #define CLIDR_CTYPE_SHIFT(level) (3 * (level - 1))
32 #define CLIDR_CTYPE_MASK(level) (7 << CLIDR_CTYPE_SHIFT(level))
33 #define CLIDR_CTYPE(clidr, level) \
34 (((clidr) & CLIDR_CTYPE_MASK(level)) >> CLIDR_CTYPE_SHIFT(level))
35
get_cache_type(int level)36 static inline enum cache_type get_cache_type(int level)
37 {
38 u64 clidr;
39
40 if (level > MAX_CACHE_LEVEL)
41 return CACHE_TYPE_NOCACHE;
42 asm volatile ("mrs %x0, clidr_el1" : "=r" (clidr));
43 return CLIDR_CTYPE(clidr, level);
44 }
45
46 /*
47 * Cache Size Selection Register(CSSELR) selects which Cache Size ID
48 * Register(CCSIDR) is accessible by specifying the required cache
49 * level and the cache type. We need to ensure that no one else changes
50 * CSSELR by calling this in non-preemtible context
51 */
cache_get_ccsidr(u64 csselr)52 u64 __attribute_const__ cache_get_ccsidr(u64 csselr)
53 {
54 u64 ccsidr;
55
56 WARN_ON(preemptible());
57
58 /* Put value into CSSELR */
59 asm volatile("msr csselr_el1, %x0" : : "r" (csselr));
60 isb();
61 /* Read result out of CCSIDR */
62 asm volatile("mrs %x0, ccsidr_el1" : "=r" (ccsidr));
63
64 return ccsidr;
65 }
66
ci_leaf_init(struct cacheinfo * this_leaf,enum cache_type type,unsigned int level)67 static void ci_leaf_init(struct cacheinfo *this_leaf,
68 enum cache_type type, unsigned int level)
69 {
70 bool is_icache = type & CACHE_TYPE_INST;
71 u64 tmp = cache_get_ccsidr((level - 1) << 1 | is_icache);
72
73 this_leaf->level = level;
74 this_leaf->type = type;
75 this_leaf->coherency_line_size = CACHE_LINESIZE(tmp);
76 this_leaf->number_of_sets = CACHE_NUMSETS(tmp);
77 this_leaf->ways_of_associativity = CACHE_ASSOCIATIVITY(tmp);
78 this_leaf->size = this_leaf->number_of_sets *
79 this_leaf->coherency_line_size * this_leaf->ways_of_associativity;
80 this_leaf->attributes =
81 ((tmp & CCSIDR_EL1_WRITE_THROUGH) ? CACHE_WRITE_THROUGH : 0) |
82 ((tmp & CCSIDR_EL1_WRITE_BACK) ? CACHE_WRITE_BACK : 0) |
83 ((tmp & CCSIDR_EL1_READ_ALLOCATE) ? CACHE_READ_ALLOCATE : 0) |
84 ((tmp & CCSIDR_EL1_WRITE_ALLOCATE) ? CACHE_WRITE_ALLOCATE : 0);
85 }
86
__init_cache_level(unsigned int cpu)87 static int __init_cache_level(unsigned int cpu)
88 {
89 unsigned int ctype, level, leaves;
90 struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
91
92 for (level = 1, leaves = 0; level <= MAX_CACHE_LEVEL; level++) {
93 ctype = get_cache_type(level);
94 if (ctype == CACHE_TYPE_NOCACHE) {
95 level--;
96 break;
97 }
98 /* Separate instruction and data caches */
99 leaves += (ctype == CACHE_TYPE_SEPARATE) ? 2 : 1;
100 }
101
102 this_cpu_ci->num_levels = level;
103 this_cpu_ci->num_leaves = leaves;
104 return 0;
105 }
106
__populate_cache_leaves(unsigned int cpu)107 static int __populate_cache_leaves(unsigned int cpu)
108 {
109 unsigned int level, idx;
110 enum cache_type type;
111 struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
112 struct cacheinfo *this_leaf = this_cpu_ci->info_list;
113
114 for (idx = 0, level = 1; level <= this_cpu_ci->num_levels &&
115 idx < this_cpu_ci->num_leaves; idx++, level++) {
116 type = get_cache_type(level);
117 if (type == CACHE_TYPE_SEPARATE) {
118 ci_leaf_init(this_leaf++, CACHE_TYPE_DATA, level);
119 ci_leaf_init(this_leaf++, CACHE_TYPE_INST, level);
120 } else {
121 ci_leaf_init(this_leaf++, type, level);
122 }
123 }
124 return 0;
125 }
126
127 DEFINE_SMP_CALL_CACHE_FUNCTION(init_cache_level)
128 DEFINE_SMP_CALL_CACHE_FUNCTION(populate_cache_leaves)
129