1 files changed, 189 insertions, 0 deletions
diff --git a/arch/riscv/kernel/cacheinfo.c b/arch/riscv/kernel/cacheinfo.c
new file mode 100644
index 000000000..90deabfe6
--- /dev/null
+++ b/arch/riscv/kernel/cacheinfo.c
@@ -0,0 +1,189 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2017 SiFive
+ */
+
+#include <linux/cpu.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <asm/cacheinfo.h>
+
+static struct riscv_cacheinfo_ops *rv_cache_ops;
+
+void riscv_set_cacheinfo_ops(struct riscv_cacheinfo_ops *ops)
+{
+	rv_cache_ops = ops;
+}
+EXPORT_SYMBOL_GPL(riscv_set_cacheinfo_ops);
+
+const struct attribute_group *
+cache_get_priv_group(struct cacheinfo *this_leaf)
+{
+	if (rv_cache_ops && rv_cache_ops->get_priv_group)
+		return rv_cache_ops->get_priv_group(this_leaf);
+	return NULL;
+}
+
+static struct cacheinfo *get_cacheinfo(u32 level, enum cache_type type)
+{
+	/*
+	 * Using raw_smp_processor_id() elides a preemptability check, but this
+	 * is really indicative of a larger problem: the cacheinfo UABI assumes
+	 * that cores have a homonogenous view of the cache hierarchy.  That
+	 * happens to be the case for the current set of RISC-V systems, but
+	 * likely won't be true in general.  Since there's no way to provide
+	 * correct information for these systems via the current UABI we're
+	 * just eliding the check for now.
+	 */
+	struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(raw_smp_processor_id());
+	struct cacheinfo *this_leaf;
+	int index;
+
+	for (index = 0; index < this_cpu_ci->num_leaves; index++) {
+		this_leaf = this_cpu_ci->info_list + index;
+		if (this_leaf->level == level && this_leaf->type == type)
+			return this_leaf;
+	}
+
+	return NULL;
+}
+
+uintptr_t get_cache_size(u32 level, enum cache_type type)
+{
+	struct cacheinfo *this_leaf = get_cacheinfo(level, type);
+
+	return this_leaf ? this_leaf->size : 0;
+}
+
+uintptr_t get_cache_geometry(u32 level, enum cache_type type)
+{
+	struct cacheinfo *this_leaf = get_cacheinfo(level, type);
+
+	return this_leaf ? (this_leaf->ways_of_associativity << 16 |
+			    this_leaf->coherency_line_size) :
+			   0;
+}
+
+static void ci_leaf_init(struct cacheinfo *this_leaf, enum cache_type type,
+			 unsigned int level, unsigned int size,
+			 unsigned int sets, unsigned int line_size)
+{
+	this_leaf->level = level;
+	this_leaf->type = type;
+	this_leaf->size = size;
+	this_leaf->number_of_sets = sets;
+	this_leaf->coherency_line_size = line_size;
+
+	/*
+	 * If the cache is fully associative, there is no need to
+	 * check the other properties.
+	 */
+	if (sets == 1)
+		return;
+
+	/*
+	 * Set the ways number for n-ways associative, make sure
+	 * all properties are big than zero.
+	 */
+	if (sets > 0 && size > 0 && line_size > 0)
+		this_leaf->ways_of_associativity = (size / sets) / line_size;
+}
+
+static void fill_cacheinfo(struct cacheinfo **this_leaf,
+			   struct device_node *node, unsigned int level)
+{
+	unsigned int size, sets, line_size;
+
+	if (!of_property_read_u32(node, "cache-size", &size) &&
+	    !of_property_read_u32(node, "cache-block-size", &line_size) &&
+	    !of_property_read_u32(node, "cache-sets", &sets)) {
+		ci_leaf_init((*this_leaf)++, CACHE_TYPE_UNIFIED, level, size, sets, line_size);
+	}
+
+	if (!of_property_read_u32(node, "i-cache-size", &size) &&
+	    !of_property_read_u32(node, "i-cache-sets", &sets) &&
+	    !of_property_read_u32(node, "i-cache-block-size", &line_size)) {
+		ci_leaf_init((*this_leaf)++, CACHE_TYPE_INST, level, size, sets, line_size);
+	}
+
+	if (!of_property_read_u32(node, "d-cache-size", &size) &&
+	    !of_property_read_u32(node, "d-cache-sets", &sets) &&
+	    !of_property_read_u32(node, "d-cache-block-size", &line_size)) {
+		ci_leaf_init((*this_leaf)++, CACHE_TYPE_DATA, level, size, sets, line_size);
+	}
+}
+
+int init_cache_level(unsigned int cpu)
+{
+	struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
+	struct device_node *np = of_cpu_device_node_get(cpu);
+	struct device_node *prev = NULL;
+	int levels = 0, leaves = 0, level;
+
+	if (of_property_read_bool(np, "cache-size"))
+		++leaves;
+	if (of_property_read_bool(np, "i-cache-size"))
+		++leaves;
+	if (of_property_read_bool(np, "d-cache-size"))
+		++leaves;
+	if (leaves > 0)
+		levels = 1;
+
+	prev = np;
+	while ((np = of_find_next_cache_node(np))) {
+		of_node_put(prev);
+		prev = np;
+		if (!of_device_is_compatible(np, "cache"))
+			break;
+		if (of_property_read_u32(np, "cache-level", &level))
+			break;
+		if (level <= levels)
+			break;
+		if (of_property_read_bool(np, "cache-size"))
+			++leaves;
+		if (of_property_read_bool(np, "i-cache-size"))
+			++leaves;
+		if (of_property_read_bool(np, "d-cache-size"))
+			++leaves;
+		levels = level;
+	}
+
+	of_node_put(np);
+	this_cpu_ci->num_levels = levels;
+	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;
+	struct device_node *np = of_cpu_device_node_get(cpu);
+	struct device_node *prev = NULL;
+	int levels = 1, level = 1;
+
+	/* Level 1 caches in cpu node */
+	fill_cacheinfo(&this_leaf, np, level);
+
+	/* Next level caches in cache nodes */
+	prev = np;
+	while ((np = of_find_next_cache_node(np))) {
+		of_node_put(prev);
+		prev = np;
+
+		if (!of_device_is_compatible(np, "cache"))
+			break;
+		if (of_property_read_u32(np, "cache-level", &level))
+			break;
+		if (level <= levels)
+			break;
+
+		fill_cacheinfo(&this_leaf, np, level);
+
+		levels = level;
+	}
+	of_node_put(np);
+
+	return 0;
+}