1 files changed, 359 insertions, 0 deletions
diff --git a/arch/s390/kernel/cache.c b/arch/s390/kernel/cache.c
new file mode 100644
index 00000000000..5e20bab4df2
--- /dev/null
+++ b/arch/s390/kernel/cache.c
@@ -0,0 +1,359 @@
+/*
+ * Extract CPU cache information and expose them via sysfs.
+ *
+ *    Copyright IBM Corp. 2012
+ *    Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
+ */
+
+#include <linux/notifier.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/cpu.h>
+#include <asm/facility.h>
+
+struct cache {
+	unsigned long size;
+	unsigned int line_size;
+	unsigned int associativity;
+	unsigned int nr_sets;
+	int level;
+	int type;
+	struct list_head list;
+};
+
+struct cache_dir {
+	struct kobject *kobj;
+	struct cache_index_dir *index;
+};
+
+struct cache_index_dir {
+	struct kobject kobj;
+	int cpu;
+	struct cache *cache;
+	struct cache_index_dir *next;
+};
+
+enum {
+	CACHE_SCOPE_NOTEXISTS,
+	CACHE_SCOPE_PRIVATE,
+	CACHE_SCOPE_SHARED,
+	CACHE_SCOPE_RESERVED,
+};
+
+enum {
+	CACHE_TYPE_SEPARATE,
+	CACHE_TYPE_DATA,
+	CACHE_TYPE_INSTRUCTION,
+	CACHE_TYPE_UNIFIED,
+};
+
+enum {
+	EXTRACT_TOPOLOGY,
+	EXTRACT_LINE_SIZE,
+	EXTRACT_SIZE,
+	EXTRACT_ASSOCIATIVITY,
+};
+
+enum {
+	CACHE_TI_UNIFIED = 0,
+	CACHE_TI_INSTRUCTION = 0,
+	CACHE_TI_DATA,
+};
+
+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[] = {
+	"Data",
+	"Instruction",
+	"Unified",
+};
+
+static struct cache_dir *cache_dir_cpu[NR_CPUS];
+static LIST_HEAD(cache_list);
+
+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 int __init cache_add(int level, int type)
+{
+	struct cache *cache;
+	int ti;
+
+	cache = kzalloc(sizeof(*cache), GFP_KERNEL);
+	if (!cache)
+		return -ENOMEM;
+	ti = type == CACHE_TYPE_DATA ? CACHE_TI_DATA : CACHE_TI_UNIFIED;
+	cache->size = ecag(EXTRACT_SIZE, level, ti);
+	cache->line_size = ecag(EXTRACT_LINE_SIZE, level, ti);
+	cache->associativity = ecag(EXTRACT_ASSOCIATIVITY, level, ti);
+	cache->nr_sets = cache->size / cache->associativity;
+	cache->nr_sets /= cache->line_size;
+	cache->level = level + 1;
+	cache->type = type;
+	list_add_tail(&cache->list, &cache_list);
+	return 0;
+}
+
+static void __init cache_build_info(void)
+{
+	struct cache *cache, *next;
+	union cache_topology ct;
+	int level, rc;
+
+	ct.raw = ecag(EXTRACT_TOPOLOGY, 0, 0);
+	for (level = 0; level < CACHE_MAX_LEVEL; level++) {
+		switch (ct.ci[level].scope) {
+		case CACHE_SCOPE_NOTEXISTS:
+		case CACHE_SCOPE_RESERVED:
+		case CACHE_SCOPE_SHARED:
+			return;
+		case CACHE_SCOPE_PRIVATE:
+			break;
+		}
+		if (ct.ci[level].type == CACHE_TYPE_SEPARATE) {
+			rc  = cache_add(level, CACHE_TYPE_DATA);
+			rc |= cache_add(level, CACHE_TYPE_INSTRUCTION);
+		} else {
+			rc = cache_add(level, ct.ci[level].type);
+		}
+		if (rc)
+			goto error;
+	}
+	return;
+error:
+	list_for_each_entry_safe(cache, next, &cache_list, list) {
+		list_del(&cache->list);
+		kfree(cache);
+	}
+}
+
+static struct cache_dir *__cpuinit cache_create_cache_dir(int cpu)
+{
+	struct cache_dir *cache_dir;
+	struct kobject *kobj = NULL;
+	struct device *dev;
+
+	dev = get_cpu_device(cpu);
+	if (!dev)
+		goto out;
+	kobj = kobject_create_and_add("cache", &dev->kobj);
+	if (!kobj)
+		goto out;
+	cache_dir = kzalloc(sizeof(*cache_dir), GFP_KERNEL);
+	if (!cache_dir)
+		goto out;
+	cache_dir->kobj = kobj;
+	cache_dir_cpu[cpu] = cache_dir;
+	return cache_dir;
+out:
+	kobject_put(kobj);
+	return NULL;
+}
+
+static struct cache_index_dir *kobj_to_cache_index_dir(struct kobject *kobj)
+{
+	return container_of(kobj, struct cache_index_dir, kobj);
+}
+
+static void cache_index_release(struct kobject *kobj)
+{
+	struct cache_index_dir *index;
+
+	index = kobj_to_cache_index_dir(kobj);
+	kfree(index);
+}
+
+static ssize_t cache_index_show(struct kobject *kobj,
+				struct attribute *attr, char *buf)
+{
+	struct kobj_attribute *kobj_attr;
+
+	kobj_attr = container_of(attr, struct kobj_attribute, attr);
+	return kobj_attr->show(kobj, kobj_attr, buf);
+}
+
+#define DEFINE_CACHE_ATTR(_name, _format, _value)			\
+static ssize_t cache_##_name##_show(struct kobject *kobj,		\
+				    struct kobj_attribute *attr,	\
+				    char *buf)				\
+{									\
+	struct cache_index_dir *index;					\
+									\
+	index = kobj_to_cache_index_dir(kobj);				\
+	return sprintf(buf, _format, _value);				\
+}									\
+static struct kobj_attribute cache_##_name##_attr =			\
+	__ATTR(_name, 0444, cache_##_name##_show, NULL);
+
+DEFINE_CACHE_ATTR(size, "%luK\n", index->cache->size >> 10);
+DEFINE_CACHE_ATTR(coherency_line_size, "%u\n", index->cache->line_size);
+DEFINE_CACHE_ATTR(number_of_sets, "%u\n", index->cache->nr_sets);
+DEFINE_CACHE_ATTR(ways_of_associativity, "%u\n", index->cache->associativity);
+DEFINE_CACHE_ATTR(type, "%s\n", cache_type_string[index->cache->type - 1]);
+DEFINE_CACHE_ATTR(level, "%d\n", index->cache->level);
+
+static ssize_t shared_cpu_map_func(struct kobject *kobj, int type, char *buf)
+{
+	struct cache_index_dir *index;
+	int len;
+
+	index = kobj_to_cache_index_dir(kobj);
+	len = type ?
+		cpulist_scnprintf(buf, PAGE_SIZE - 2, cpumask_of(index->cpu)) :
+		cpumask_scnprintf(buf, PAGE_SIZE - 2, cpumask_of(index->cpu));
+	len += sprintf(&buf[len], "\n");
+	return len;
+}
+
+static ssize_t shared_cpu_map_show(struct kobject *kobj,
+				   struct kobj_attribute *attr, char *buf)
+{
+	return shared_cpu_map_func(kobj, 0, buf);
+}
+static struct kobj_attribute cache_shared_cpu_map_attr =
+	__ATTR(shared_cpu_map, 0444, shared_cpu_map_show, NULL);
+
+static ssize_t shared_cpu_list_show(struct kobject *kobj,
+				    struct kobj_attribute *attr, char *buf)
+{
+	return shared_cpu_map_func(kobj, 1, buf);
+}
+static struct kobj_attribute cache_shared_cpu_list_attr =
+	__ATTR(shared_cpu_list, 0444, shared_cpu_list_show, NULL);
+
+static struct attribute *cache_index_default_attrs[] = {
+	&cache_type_attr.attr,
+	&cache_size_attr.attr,
+	&cache_number_of_sets_attr.attr,
+	&cache_ways_of_associativity_attr.attr,
+	&cache_level_attr.attr,
+	&cache_coherency_line_size_attr.attr,
+	&cache_shared_cpu_map_attr.attr,
+	&cache_shared_cpu_list_attr.attr,
+	NULL,
+};
+
+static const struct sysfs_ops cache_index_ops = {
+	.show = cache_index_show,
+};
+
+static struct kobj_type cache_index_type = {
+	.sysfs_ops = &cache_index_ops,
+	.release = cache_index_release,
+	.default_attrs = cache_index_default_attrs,
+};
+
+static int __cpuinit cache_create_index_dir(struct cache_dir *cache_dir,
+					    struct cache *cache, int index,
+					    int cpu)
+{
+	struct cache_index_dir *index_dir;
+	int rc;
+
+	index_dir = kzalloc(sizeof(*index_dir), GFP_KERNEL);
+	if (!index_dir)
+		return -ENOMEM;
+	index_dir->cache = cache;
+	index_dir->cpu = cpu;
+	rc = kobject_init_and_add(&index_dir->kobj, &cache_index_type,
+				  cache_dir->kobj, "index%d", index);
+	if (rc)
+		goto out;
+	index_dir->next = cache_dir->index;
+	cache_dir->index = index_dir;
+	return 0;
+out:
+	kfree(index_dir);
+	return rc;
+}
+
+static int __cpuinit cache_add_cpu(int cpu)
+{
+	struct cache_dir *cache_dir;
+	struct cache *cache;
+	int rc, index = 0;
+
+	if (list_empty(&cache_list))
+		return 0;
+	cache_dir = cache_create_cache_dir(cpu);
+	if (!cache_dir)
+		return -ENOMEM;
+	list_for_each_entry(cache, &cache_list, list) {
+		rc = cache_create_index_dir(cache_dir, cache, index, cpu);
+		if (rc)
+			return rc;
+		index++;
+	}
+	return 0;
+}
+
+static void __cpuinit cache_remove_cpu(int cpu)
+{
+	struct cache_index_dir *index, *next;
+	struct cache_dir *cache_dir;
+
+	cache_dir = cache_dir_cpu[cpu];
+	if (!cache_dir)
+		return;
+	index = cache_dir->index;
+	while (index) {
+		next = index->next;
+		kobject_put(&index->kobj);
+		index = next;
+	}
+	kobject_put(cache_dir->kobj);
+	kfree(cache_dir);
+	cache_dir_cpu[cpu] = NULL;
+}
+
+static int __cpuinit cache_hotplug(struct notifier_block *nfb,
+				   unsigned long action, void *hcpu)
+{
+	int cpu = (long)hcpu;
+	int rc = 0;
+
+	switch (action & ~CPU_TASKS_FROZEN) {
+	case CPU_ONLINE:
+		rc = cache_add_cpu(cpu);
+		if (rc)
+			cache_remove_cpu(cpu);
+		break;
+	case CPU_DEAD:
+		cache_remove_cpu(cpu);
+		break;
+	}
+	return rc ? NOTIFY_BAD : NOTIFY_OK;
+}
+
+static int __init cache_init(void)
+{
+	int cpu;
+
+	if (!test_facility(34))
+		return 0;
+	cache_build_info();
+	for_each_online_cpu(cpu)
+		cache_add_cpu(cpu);
+	hotcpu_notifier(cache_hotplug, 0);
+	return 0;
+}
+device_initcall(cache_init);