of/address: Add of_range_to_resource() helper

A few users need to convert a specific "ranges" entry into a struct
resource. Add a helper to similar to of_address_to_resource(). The
existing of_pci_range_to_resource() helper isn't really PCI specific,
so it can be used with the CONFIG_PCI check dropped.

Link: https://lore.kernel.org/r/20230328-dt-address-helpers-v1-2-e2456c3e77ab@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>

diff --git a/drivers/of/address.c b/drivers/of/address.c
index 4c0b169..b79f005 100644 (file)
--- a/drivers/of/address.c
+++ b/drivers/of/address.c
@@ -229,9 +229,6 @@ int of_pci_range_to_resource(struct of_pci_range *range,
        res->parent = res->child = res->sibling = NULL;
        res->name = np->full_name;
 
-       if (!IS_ENABLED(CONFIG_PCI))
-               return -ENOSYS;
-
        if (res->flags & IORESOURCE_IO) {
                unsigned long port;
                err = pci_register_io_range(&np->fwnode, range->cpu_addr,
@@ -264,6 +261,34 @@ invalid_range:
 EXPORT_SYMBOL(of_pci_range_to_resource);
 
 /*
+ * of_range_to_resource - Create a resource from a ranges entry
+ * @np:                device node where the range belongs to
+ * @index:     the 'ranges' index to convert to a resource
+ * @res:       pointer to a valid resource that will be updated to
+ *              reflect the values contained in the range.
+ *
+ * Returns ENOENT if the entry is not found or EINVAL if the range cannot be
+ * converted to resource.
+ */
+int of_range_to_resource(struct device_node *np, int index, struct resource *res)
+{
+       int ret, i = 0;
+       struct of_range_parser parser;
+       struct of_range range;
+
+       ret = of_range_parser_init(&parser, np);
+       if (ret)
+               return ret;
+
+       for_each_of_range(&parser, &range)
+               if (i++ == index)
+                       return of_pci_range_to_resource(&range, np, res);
+
+       return -ENOENT;
+}
+EXPORT_SYMBOL(of_range_to_resource);
+
+/*
  * ISA bus specific translator
  */
 

diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c
index 1a45df1..945288d 100644 (file)
--- a/drivers/of/unittest.c
+++ b/drivers/of/unittest.c
@@ -1013,7 +1013,8 @@ static void __init of_unittest_bus_ranges(void)
        struct device_node *np;
        struct of_range range;
        struct of_range_parser parser;
-       int i = 0;
+       struct resource res;
+       int ret, i = 0;
 
        np = of_find_node_by_path("/testcase-data/address-tests");
        if (!np) {
@@ -1026,6 +1027,19 @@ static void __init of_unittest_bus_ranges(void)
                return;
        }
 
+       ret = of_range_to_resource(np, 1, &res);
+       unittest(!ret, "of_range_to_resource returned error (%d) node %pOF\n",
+               ret, np);
+       unittest(resource_type(&res) == IORESOURCE_MEM,
+               "of_range_to_resource wrong resource type on node %pOF res=%pR\n",
+               np, &res);
+       unittest(res.start == 0xd0000000,
+               "of_range_to_resource wrong resource start address on node %pOF res=%pR\n",
+               np, &res);
+       unittest(resource_size(&res) == 0x20000000,
+               "of_range_to_resource wrong resource start address on node %pOF res=%pR\n",
+               np, &res);
+
        /*
         * Get the "ranges" from the device tree
         */

diff --git a/include/linux/of_address.h b/include/linux/of_address.h
index 3766715..1d00543 100644 (file)
--- a/include/linux/of_address.h
+++ b/include/linux/of_address.h
@@ -68,6 +68,8 @@ extern int of_pci_address_to_resource(struct device_node *dev, int bar,
 extern int of_pci_range_to_resource(struct of_pci_range *range,
                                    struct device_node *np,
                                    struct resource *res);
+extern int of_range_to_resource(struct device_node *np, int index,
+                               struct resource *res);
 extern bool of_dma_is_coherent(struct device_node *np);
 #else /* CONFIG_OF_ADDRESS */
 static inline void __iomem *of_io_request_and_map(struct device_node *device,
@@ -120,6 +122,12 @@ static inline int of_pci_range_to_resource(struct of_pci_range *range,
        return -ENOSYS;
 }
 
+static inline int of_range_to_resource(struct device_node *np, int index,
+                                      struct resource *res)
+{
+       return -ENOSYS;
+}
+
 static inline bool of_dma_is_coherent(struct device_node *np)
 {
        return false;