linux/arch/arm64/kernel/cacheinfo.c

138 lines
4.1 KiB
C

/*
* ARM64 cacheinfo support
*
* Copyright (C) 2015 ARM Ltd.
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed "as is" WITHOUT ANY WARRANTY of any
* kind, whether express or implied; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/bitops.h>
#include <linux/cacheinfo.h>
#include <linux/cpu.h>
#include <linux/compiler.h>
#include <linux/of.h>
#include <asm/cachetype.h>
#include <asm/processor.h>
#define MAX_CACHE_LEVEL 7 /* Max 7 level supported */
/* Ctypen, bits[3(n - 1) + 2 : 3(n - 1)], for n = 1 to 7 */
#define CLIDR_CTYPE_SHIFT(level) (3 * (level - 1))
#define CLIDR_CTYPE_MASK(level) (7 << CLIDR_CTYPE_SHIFT(level))
#define CLIDR_CTYPE(clidr, level) \
(((clidr) & CLIDR_CTYPE_MASK(level)) >> CLIDR_CTYPE_SHIFT(level))
static inline enum cache_type get_cache_type(int level)
{
u64 clidr;
if (level > MAX_CACHE_LEVEL)
return CACHE_TYPE_NOCACHE;
clidr = read_sysreg(clidr_el1);
return CLIDR_CTYPE(clidr, level);
}
/*
* Cache Size Selection Register(CSSELR) selects which Cache Size ID
* Register(CCSIDR) is accessible by specifying the required cache
* level and the cache type. We need to ensure that no one else changes
* CSSELR by calling this in non-preemtible context
*/
u64 __attribute_const__ cache_get_ccsidr(u64 csselr)
{
u64 ccsidr;
WARN_ON(preemptible());
write_sysreg(csselr, csselr_el1);
isb();
ccsidr = read_sysreg(ccsidr_el1);
return ccsidr;
}
static void ci_leaf_init(struct cacheinfo *this_leaf,
enum cache_type type, unsigned int level)
{
bool is_icache = type & CACHE_TYPE_INST;
u64 tmp = cache_get_ccsidr((level - 1) << 1 | is_icache);
this_leaf->level = level;
this_leaf->type = type;
this_leaf->coherency_line_size = CACHE_LINESIZE(tmp);
this_leaf->number_of_sets = CACHE_NUMSETS(tmp);
this_leaf->ways_of_associativity = CACHE_ASSOCIATIVITY(tmp);
this_leaf->size = this_leaf->number_of_sets *
this_leaf->coherency_line_size * this_leaf->ways_of_associativity;
this_leaf->attributes =
((tmp & CCSIDR_EL1_WRITE_THROUGH) ? CACHE_WRITE_THROUGH : 0) |
((tmp & CCSIDR_EL1_WRITE_BACK) ? CACHE_WRITE_BACK : 0) |
((tmp & CCSIDR_EL1_READ_ALLOCATE) ? CACHE_READ_ALLOCATE : 0) |
((tmp & CCSIDR_EL1_WRITE_ALLOCATE) ? CACHE_WRITE_ALLOCATE : 0);
}
static int __init_cache_level(unsigned int cpu)
{
unsigned int ctype, level, leaves, of_level;
struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
for (level = 1, leaves = 0; level <= MAX_CACHE_LEVEL; level++) {
ctype = get_cache_type(level);
if (ctype == CACHE_TYPE_NOCACHE) {
level--;
break;
}
/* Separate instruction and data caches */
leaves += (ctype == CACHE_TYPE_SEPARATE) ? 2 : 1;
}
of_level = of_find_last_cache_level(cpu);
if (level < of_level) {
/*
* some external caches not specified in CLIDR_EL1
* the information may be available in the device tree
* only unified external caches are considered here
*/
leaves += (of_level - level);
level = of_level;
}
this_cpu_ci->num_levels = level;
this_cpu_ci->num_leaves = leaves;
return 0;
}
static int __populate_cache_leaves(unsigned int cpu)
{
unsigned int level, idx;
enum cache_type type;
struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
struct cacheinfo *this_leaf = this_cpu_ci->info_list;
for (idx = 0, level = 1; level <= this_cpu_ci->num_levels &&
idx < this_cpu_ci->num_leaves; idx++, level++) {
type = get_cache_type(level);
if (type == CACHE_TYPE_SEPARATE) {
ci_leaf_init(this_leaf++, CACHE_TYPE_DATA, level);
ci_leaf_init(this_leaf++, CACHE_TYPE_INST, level);
} else {
ci_leaf_init(this_leaf++, type, level);
}
}
return 0;
}
DEFINE_SMP_CALL_CACHE_FUNCTION(init_cache_level)
DEFINE_SMP_CALL_CACHE_FUNCTION(populate_cache_leaves)