Drivers with "memory-region" properties currently have to do their own
parsing of "memory-region" properties. The result is all the drivers
have similar patterns of a call to parse "memory-region" and then get
the region's address and size. As this is a standard property, it should
have common functions for drivers to use. Add new functions to count the
number of regions and retrieve the region's address as a resource.
Signed-off-by: Rob Herring (Arm) <robh@xxxxxxxxxx>
---
drivers/of/of_reserved_mem.c | 77 +++++++++++++++++++++++++++++++++
include/linux/of_reserved_mem.h | 26 +++++++++++
2 files changed, 103 insertions(+)
diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c
index 75e819f66a56..fd50038dff76 100644
--- a/drivers/of/of_reserved_mem.c
+++ b/drivers/of/of_reserved_mem.c
@@ -12,6 +12,7 @@
#define pr_fmt(fmt) "OF: reserved mem: " fmt
#include <linux/err.h>
+#include <linux/ioport.h>
#include <linux/libfdt.h>
#include <linux/of.h>
#include <linux/of_fdt.h>
@@ -740,3 +741,79 @@ struct reserved_mem *of_reserved_mem_lookup(struct device_node *np)
return NULL;
}
EXPORT_SYMBOL_GPL(of_reserved_mem_lookup);
+
+/**
+ * of_reserved_mem_region_to_resource() - Get a reserved memory region as a resource
+ * @np: node containing 'memory-region' property
+ * @idx: index of 'memory-region' property to lookup
+ * @res: Pointer to a struct resource to fill in with reserved region
+ *
+ * This function allows drivers to lookup a node's 'memory-region' property
+ * entries by index and return a struct resource for the entry.
+ *
+ * Returns 0 on success with @res filled in. Returns -ENODEV if 'memory-region'
+ * is missing or unavailable, -EINVAL for any other error.
+ */
+int of_reserved_mem_region_to_resource(const struct device_node *np, unsigned int idx, struct resource *res)
+{
+ struct reserved_mem *rmem;
+
+ if (!np)
+ return -EINVAL;
+
+ struct device_node __free(device_node) *target = of_parse_phandle(np, "memory-region", idx);
+ if (!target || !of_device_is_available(target))
+ return -ENODEV;
+
+ rmem = of_reserved_mem_lookup(target);
+ if (!rmem)
+ return -EINVAL;
+
+ resource_set_range(res, rmem->base, rmem->size);
+ res->name = rmem->name;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(of_reserved_mem_region_to_resource);
+
+/**
+ * of_reserved_mem_region_to_resource_byname() - Get a reserved memory region as a resource
+ * @np: node containing 'memory-region' property
+ * @name: name of 'memory-region' property entry to lookup
+ * @res: Pointer to a struct resource to fill in with reserved region
+ *
+ * This function allows drivers to lookup a node's 'memory-region' property
+ * entries by name and return a struct resource for the entry.
+ *
+ * Returns 0 on success with @res filled in. Returns -ENODEV if 'memory-region'
+ * is missing or unavailable, -EINVAL for any other error.
+ */
+int of_reserved_mem_region_to_resource_byname(const struct device_node *np, const char *name, struct resource *res)
+{
+ int idx;
+
+ if (!name)
+ return -EINVAL;
+
+ idx = of_property_match_string(np, "memory-region-names", name);
+ if (idx < 0)
+ return idx;
+
+ return of_reserved_mem_region_to_resource(np, idx, res);
+}
+EXPORT_SYMBOL_GPL(of_reserved_mem_region_to_resource_byname);
+
+/**
+ * of_reserved_mem_region_count() - Return the number of 'memory-region' entries
+ * @np: node containing 'memory-region' property
+ *
+ * This function allows drivers to retrieve the number of entries for a node's
+ * 'memory-region' property.
+ *
+ * Returns the number of entries on success, or negative error code on a
+ * malformed property.
+ */
+int of_reserved_mem_region_count(const struct device_node *np)
+{
+ return of_count_phandle_with_args(np, "memory-region", NULL);
+}
+EXPORT_SYMBOL_GPL(of_reserved_mem_region_count);
diff --git a/include/linux/of_reserved_mem.h b/include/linux/of_reserved_mem.h
index e338282da652..f573423359f4 100644
--- a/include/linux/of_reserved_mem.h
+++ b/include/linux/of_reserved_mem.h
@@ -7,6 +7,7 @@
struct of_phandle_args;
struct reserved_mem_ops;
+struct resource;
struct reserved_mem {
const char *name;
@@ -39,6 +40,12 @@ int of_reserved_mem_device_init_by_name(struct device *dev,
void of_reserved_mem_device_release(struct device *dev);
struct reserved_mem *of_reserved_mem_lookup(struct device_node *np);
+int of_reserved_mem_region_to_resource(const struct device_node *np,
+ unsigned int idx, struct resource *res);
+int of_reserved_mem_region_to_resource_byname(const struct device_node *np,
+ const char *name, struct resource *res);
+int of_reserved_mem_region_count(const struct device_node *np);
+
#else
#define RESERVEDMEM_OF_DECLARE(name, compat, init) \
@@ -63,6 +70,25 @@ static inline struct reserved_mem *of_reserved_mem_lookup(struct device_node *np
{
return NULL;
}
+
+static inline int of_reserved_mem_region_to_resource(const struct device_node *np,
+ unsigned int idx,
+ struct resource *res)
+{
+ return -ENOSYS;
+}
+
+static inline int of_reserved_mem_region_to_resource_byname(const struct device_node *np,
+ const char *name,
+ struct resource *res)
+{
+ return -ENOSYS;
+}
+
+static inline int of_reserved_mem_region_count(const struct device_node *np)
+{
+ return 0;
+}
#endif
/**
--
2.47.2
