@@ -368,13 +368,17 @@ dt_find_matching_node(struct dt_device_node *from,
return NULL;
}
-int dt_n_addr_cells(const struct dt_device_node *np)
+/* If parent is true then start from the parent. */
+static int dt_n_addr_cells_common(const struct dt_device_node *np, bool parent)
{
const __be32 *ip;
do {
- if ( np->parent )
+ if ( parent && np->parent )
np = np->parent;
+ else
+ parent = 1;
+
ip = dt_get_property(np, "#address-cells", NULL);
if ( ip )
return be32_to_cpup(ip);
@@ -383,13 +387,26 @@ int dt_n_addr_cells(const struct dt_device_node *np)
return DT_ROOT_NODE_ADDR_CELLS_DEFAULT;
}
-int dt_n_size_cells(const struct dt_device_node *np)
+int dt_n_addr_cells(const struct dt_device_node *np)
+{
+ return dt_n_addr_cells_common(np, true);
+}
+
+int dt_n_addr_cells_children(const struct dt_device_node *np)
+{
+ return dt_n_addr_cells_common(np, false);
+}
+
+/* If parent is true then start from the parent. */
+static int dt_n_size_cells_common(const struct dt_device_node *np, bool parent)
{
const __be32 *ip;
do {
- if ( np->parent )
+ if ( parent && np->parent )
np = np->parent;
+ else
+ parent = 1;
ip = dt_get_property(np, "#size-cells", NULL);
if ( ip )
return be32_to_cpup(ip);
@@ -398,6 +415,16 @@ int dt_n_size_cells(const struct dt_device_node *np)
return DT_ROOT_NODE_SIZE_CELLS_DEFAULT;
}
+int dt_n_size_cells(const struct dt_device_node *np)
+{
+ return dt_n_size_cells_common(np, true);
+}
+int dt_n_size_cells_children(const struct dt_device_node *np)
+{
+ return dt_n_size_cells_common(np, false);
+}
+
+
/*
* Default translator (generic bus)
*/
@@ -513,24 +513,55 @@ int dt_device_get_raw_irq(const struct dt_device_node *device, int index,
int dt_irq_translate(const struct dt_raw_irq *raw, struct dt_irq *out_irq);
/**
- * dt_n_size_cells - Helper to retrieve the number of cell for the size
- * @np: node to get the value
+ * dt_n_size_cells - Helper to retrieve the number of cells used for
+ * size properties of a node (e.g. the size part of a reg property).
+ *
+ * @np: node to get the value for
*
- * This function retrieves for a give device-tree node the number of
- * cell for the size field.
+ * This function retrieves for a given device-tree node the number of
+ * cells used for size properties, which is the #size-cells property of
+ * the node's parent (or grandparent etc).
*/
int dt_n_size_cells(const struct dt_device_node *np);
/**
- * dt_n_addr_cells - Helper to retrieve the number of cell for the address
- * @np: node to get the value
+ * dt_n_size_cells_children - Helper to retrieve the number of cells
+ * used for size properties of child nodes.
+ *
+ * @np: node to get the value for
+ *
+ * This function retrieves the #size-cells field which will apply to
+ * this node's children, which may be specified by this node or its
+ * parent, grantparent etc.
+ */
+int dt_n_size_cells_children(const struct dt_device_node *node);
+
+/**
+ * dt_n_addr_cells - Helper to retrieve the number of cells for
+ * address properties of a node (e.g. the adddress part of a reg
+ * property).
+ *
+ * @np: node to get the value for
*
- * This function retrieves for a give device-tree node the number of
- * cell for the address field.
+ * This function retrieves for a given device-tree node the number of
+ * cells used for address properties, which is the #address-cells
+ * property of the node's parent (or grantparent, etc).
*/
int dt_n_addr_cells(const struct dt_device_node *np);
/**
+ * dt_n_size_cells_children - Helper to retrieve the number of cells
+ * used for size properties of child nodes.
+ *
+ * @np: node to get the value for
+ *
+ * This function retrieves the #address-cells field which will apply to
+ * this node's children, which may be specified by this node or its
+ * parent, grantparent etc.
+ */
+int dt_n_addr_cells_children(const struct dt_device_node *np);
+
+/**
* dt_device_is_available - Check if a device is available for use
*
* @device: Node to check for availability
The existing dt_n_{addr,size}_cells functions tell you which sizes will apply to this node, which are the #address/size-cells properties of the node's *parent* (or grandparent, etc). In some cases we need to know what size applies to a nodes children, which can include the #address/size-cells properties of the node itself (or its parent). Refactor the existing function to allow both possibilities. Clean up the grammar of the existing doc comments a bit. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> --- xen/common/device_tree.c | 35 ++++++++++++++++++++++++++---- xen/include/xen/device_tree.h | 47 ++++++++++++++++++++++++++++++++++------- 2 files changed, 70 insertions(+), 12 deletions(-)