[PATCH v6 39/42] drivers/of: Allow to specify root node in of_fdt_unflatten_tree()

Gavin Shan
2015-08-06T04:11:44Z

This introduces one more argument to of_fdt_unflatten_tree()
to specify the root node for the FDT blob, which is going to be
unflattened. In the result, the function can be used to unflatten
FDT blob, which represents device sub-tree in PowerNV hotplug
driver.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
---
drivers/of/fdt.c | 13 ++++++++-----
drivers/of/unittest.c | 2 +-
include/linux/of_fdt.h | 1 +
3 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index a18a2ce..074870a 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -388,10 +388,11 @@ static void *unflatten_dt_node(const void *blob,
struct device_node **nodepp,
bool dryrun)
{
+ unsigned long fpsize = dad ? strlen(of_node_full_name(dad)) : 0;
int depth = 1;

return __unflatten_dt_node(blob, mem, poffset,
- dad, nodepp, 0,
+ dad, nodepp, fpsize,
dryrun, &depth);
}

@@ -408,6 +409,7 @@ static void *unflatten_dt_node(const void *blob,
* 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))
{
@@ -435,7 +437,7 @@ static void __unflatten_device_tree(const void *blob,
/* First pass, scan for size */
start = 0;
size = (unsigned long)unflatten_dt_node(blob, NULL, &start,
- NULL, NULL, true);
+ dad, NULL, true);
size = ALIGN(size, 4);

pr_debug(" size is %lx, allocating...\n", size);
@@ -450,7 +452,7 @@ static void __unflatten_device_tree(const void *blob,

/* Second pass, do actual unflattening */
start = 0;
- unflatten_dt_node(blob, mem, &start, NULL, mynodes, false);
+ unflatten_dt_node(blob, mem, &start, dad, mynodes, false);
if (be32_to_cpup(mem + size) != 0xdeadbeef)
pr_warning("End of tree marker overwritten: %08x\n",
be32_to_cpup(mem + size));
@@ -472,9 +474,10 @@ 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);

@@ -1125,7 +1128,7 @@ 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 1801634..2270830 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