summaryrefslogtreecommitdiff
path: root/arch/s390/kernel/cache.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/s390/kernel/cache.c')
-rw-r--r--arch/s390/kernel/cache.c181
1 files changed, 181 insertions, 0 deletions
diff --git a/arch/s390/kernel/cache.c b/arch/s390/kernel/cache.c
new file mode 100644
index 000000000..bff5e3b6d
--- /dev/null
+++ b/arch/s390/kernel/cache.c
@@ -0,0 +1,181 @@
+/*
+ * Extract CPU cache information and expose them via sysfs.
+ *
+ * Copyright IBM Corp. 2012
+ * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
+ */
+
+#include <linux/seq_file.h>
+#include <linux/cpu.h>
+#include <linux/cacheinfo.h>
+#include <asm/facility.h>
+
+enum {
+ CACHE_SCOPE_NOTEXISTS,
+ CACHE_SCOPE_PRIVATE,
+ CACHE_SCOPE_SHARED,
+ CACHE_SCOPE_RESERVED,
+};
+
+enum {
+ CTYPE_SEPARATE,
+ CTYPE_DATA,
+ CTYPE_INSTRUCTION,
+ CTYPE_UNIFIED,
+};
+
+enum {
+ EXTRACT_TOPOLOGY,
+ EXTRACT_LINE_SIZE,
+ EXTRACT_SIZE,
+ EXTRACT_ASSOCIATIVITY,
+};
+
+enum {
+ CACHE_TI_UNIFIED = 0,
+ CACHE_TI_DATA = 0,
+ CACHE_TI_INSTRUCTION,
+};
+
+struct cache_info {
+ unsigned char : 4;
+ unsigned char scope : 2;
+ unsigned char type : 2;
+};
+
+#define CACHE_MAX_LEVEL 8
+union cache_topology {
+ struct cache_info ci[CACHE_MAX_LEVEL];
+ unsigned long long raw;
+};
+
+static const char * const cache_type_string[] = {
+ "",
+ "Instruction",
+ "Data",
+ "",
+ "Unified",
+};
+
+static const enum cache_type cache_type_map[] = {
+ [CTYPE_SEPARATE] = CACHE_TYPE_SEPARATE,
+ [CTYPE_DATA] = CACHE_TYPE_DATA,
+ [CTYPE_INSTRUCTION] = CACHE_TYPE_INST,
+ [CTYPE_UNIFIED] = CACHE_TYPE_UNIFIED,
+};
+
+void show_cacheinfo(struct seq_file *m)
+{
+ struct cpu_cacheinfo *this_cpu_ci;
+ struct cacheinfo *cache;
+ int idx;
+
+ if (!test_facility(34))
+ return;
+ get_online_cpus();
+ this_cpu_ci = get_cpu_cacheinfo(cpumask_any(cpu_online_mask));
+ for (idx = 0; idx < this_cpu_ci->num_leaves; idx++) {
+ cache = this_cpu_ci->info_list + idx;
+ seq_printf(m, "cache%-11d: ", idx);
+ seq_printf(m, "level=%d ", cache->level);
+ seq_printf(m, "type=%s ", cache_type_string[cache->type]);
+ seq_printf(m, "scope=%s ",
+ cache->disable_sysfs ? "Shared" : "Private");
+ seq_printf(m, "size=%dK ", cache->size >> 10);
+ seq_printf(m, "line_size=%u ", cache->coherency_line_size);
+ seq_printf(m, "associativity=%d", cache->ways_of_associativity);
+ seq_puts(m, "\n");
+ }
+ put_online_cpus();
+}
+
+static inline enum cache_type get_cache_type(struct cache_info *ci, int level)
+{
+ if (level >= CACHE_MAX_LEVEL)
+ return CACHE_TYPE_NOCACHE;
+ ci += level;
+ if (ci->scope != CACHE_SCOPE_SHARED && ci->scope != CACHE_SCOPE_PRIVATE)
+ return CACHE_TYPE_NOCACHE;
+ return cache_type_map[ci->type];
+}
+
+static inline unsigned long ecag(int ai, int li, int ti)
+{
+ unsigned long cmd, val;
+
+ cmd = ai << 4 | li << 1 | ti;
+ asm volatile(".insn rsy,0xeb000000004c,%0,0,0(%1)" /* ecag */
+ : "=d" (val) : "a" (cmd));
+ return val;
+}
+
+static void ci_leaf_init(struct cacheinfo *this_leaf, int private,
+ enum cache_type type, unsigned int level, int cpu)
+{
+ int ti, num_sets;
+
+ if (type == CACHE_TYPE_INST)
+ ti = CACHE_TI_INSTRUCTION;
+ else
+ ti = CACHE_TI_UNIFIED;
+ this_leaf->level = level + 1;
+ this_leaf->type = type;
+ this_leaf->coherency_line_size = ecag(EXTRACT_LINE_SIZE, level, ti);
+ this_leaf->ways_of_associativity = ecag(EXTRACT_ASSOCIATIVITY, level, ti);
+ this_leaf->size = ecag(EXTRACT_SIZE, level, ti);
+ num_sets = this_leaf->size / this_leaf->coherency_line_size;
+ num_sets /= this_leaf->ways_of_associativity;
+ this_leaf->number_of_sets = num_sets;
+ cpumask_set_cpu(cpu, &this_leaf->shared_cpu_map);
+ if (!private)
+ this_leaf->disable_sysfs = true;
+}
+
+int init_cache_level(unsigned int cpu)
+{
+ struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
+ unsigned int level = 0, leaves = 0;
+ union cache_topology ct;
+ enum cache_type ctype;
+
+ if (!this_cpu_ci)
+ return -EINVAL;
+ ct.raw = ecag(EXTRACT_TOPOLOGY, 0, 0);
+ do {
+ ctype = get_cache_type(&ct.ci[0], level);
+ if (ctype == CACHE_TYPE_NOCACHE)
+ break;
+ /* Separate instruction and data caches */
+ leaves += (ctype == CACHE_TYPE_SEPARATE) ? 2 : 1;
+ } while (++level < CACHE_MAX_LEVEL);
+ this_cpu_ci->num_levels = level;
+ this_cpu_ci->num_leaves = leaves;
+ return 0;
+}
+
+int populate_cache_leaves(unsigned int cpu)
+{
+ struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
+ struct cacheinfo *this_leaf = this_cpu_ci->info_list;
+ unsigned int level, idx, pvt;
+ union cache_topology ct;
+ enum cache_type ctype;
+
+ if (!test_facility(34))
+ return -EOPNOTSUPP;
+ ct.raw = ecag(EXTRACT_TOPOLOGY, 0, 0);
+ for (idx = 0, level = 0; level < this_cpu_ci->num_levels &&
+ idx < this_cpu_ci->num_leaves; idx++, level++) {
+ if (!this_leaf)
+ return -EINVAL;
+ pvt = (ct.ci[level].scope == CACHE_SCOPE_PRIVATE) ? 1 : 0;
+ ctype = get_cache_type(&ct.ci[0], level);
+ if (ctype == CACHE_TYPE_SEPARATE) {
+ ci_leaf_init(this_leaf++, pvt, CACHE_TYPE_DATA, level, cpu);
+ ci_leaf_init(this_leaf++, pvt, CACHE_TYPE_INST, level, cpu);
+ } else {
+ ci_leaf_init(this_leaf++, pvt, ctype, level, cpu);
+ }
+ }
+ return 0;
+}