[PATCH v7 47/50] drivers/of: Specify parent node in of_fdt_unflatten_tree()

Gavin Shan
2015-11-04T13:13:57Z

This adds one more argument to of_fdt_unflatten_tree() to specify
the parent node of the FDT blob that is going to be unflattened.
In the result, the function can be used to unflatten FDT blob that
represents device sub-tree in PowerNV PCI hotplug driver.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
---
drivers/of/fdt.c | 14 ++++++++++----
drivers/of/unittest.c | 2 +-
include/linux/of_fdt.h | 1 +
3 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 559ce49..8c8228e 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -443,11 +443,13 @@ static void *unflatten_dt_nodes(const void *blob,
* pointers of the nodes so the normal device-tree walking functions
* can be used.
* @blob: The blob to expand
+ * @dad: Parent device node
* @mynodes: The device_node tree created by the call
* @dt_alloc: An allocator that provides a virtual address to memory
* for the resulting tree
*/
static void __unflatten_device_tree(const void *blob,
+ struct device_node *dad,
struct device_node **mynodes,
void * (*dt_alloc)(u64 size, u64 align))
{
@@ -472,7 +474,7 @@ static void __unflatten_device_tree(const void *blob,
}

/* First pass, scan for size */
- size = (unsigned long)unflatten_dt_nodes(blob, NULL, NULL, NULL, true);
+ size = (unsigned long)unflatten_dt_nodes(blob, NULL, dad, NULL, true);
size = ALIGN(size, 4);

pr_debug(" size is %lx, allocating...\n", size);
@@ -486,7 +488,7 @@ static void __unflatten_device_tree(const void *blob,
pr_debug(" unflattening %p...\n", mem);

/* Second pass, do actual unflattening */
- unflatten_dt_nodes(blob, mem, NULL, mynodes, false);
+ unflatten_dt_nodes(blob, mem, dad, mynodes, false);
if (be32_to_cpup(mem + size) != 0xdeadbeef)
pr_warning("End of tree marker overwritten: %08x\n",
be32_to_cpup(mem + size));
@@ -501,6 +503,9 @@ static void *kernel_tree_alloc(u64 size, u64 align)

/**
* of_fdt_unflatten_tree - create tree of device_nodes from flat blob
+ * @blob: Flat device tree blob
+ * @dad: Parent device node
+ * @mynodes: The device tree created by the call
*
* unflattens the device-tree passed by the firmware, creating the
* tree of struct device_node. It also fills the "name" and "type"
@@ -508,9 +513,10 @@ static void *kernel_tree_alloc(u64 size, u64 align)
* can be used.
*/
void of_fdt_unflatten_tree(const unsigned long *blob,
+ struct device_node *dad,
struct device_node **mynodes)
{
- __unflatten_device_tree(blob, mynodes, &kernel_tree_alloc);
+ __unflatten_device_tree(blob, dad, mynodes, &kernel_tree_alloc);
}
EXPORT_SYMBOL_GPL(of_fdt_unflatten_tree);

@@ -1163,7 +1169,7 @@ bool __init early_init_dt_scan(void *params)
*/
void __init unflatten_device_tree(void)
{
- __unflatten_device_tree(initial_boot_params, &of_root,
+ __unflatten_device_tree(initial_boot_params, NULL, &of_root,
early_init_dt_alloc_memory_arch);

/* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */
diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c
index 9f71770b6..bafcf66 100644
--- a/drivers/of/unittest.c
+++ b/drivers/of/unittest.c
@@ -907,7 +907,7 @@ static int __init unittest_data_add(void)
"not running tests\n", __func__);
return -ENOMEM;
}
- of_fdt_unflatten_tree(unittest_data, &unittest_data_node);
+ of_fdt_unflatten_tree(unittest_data, NULL, &unittest_data_node);
if (!unittest_data_node) {
pr_warn("%s: No tree to attach; not running tests\n", __func__);
return -ENODATA;
diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h
index df9ef38..3644960 100644
--- a/include/linux/of_fdt.h
+++ b/include/linux/of_fdt.h
@@ -38,6 +38,7 @@ extern bool of_fdt_is_big_endian(const void *blob,
extern int of_fdt_match(const void *blob, unsigned long node,
const char *const *compat);
extern void of_fdt_unflatten_tree(const unsigned long *blob,
+ struct device_node *dad,
struct device_node **mynodes);

/* TBD: Temporary export of fdt globals - remove when code fully merged */
--
2.1.0