diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/of/fdt.c | 149 |
1 files changed, 98 insertions, 51 deletions
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index 71edc9cecd62..8a90ee42071a 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -11,10 +11,12 @@ #include <linux/kernel.h> #include <linux/initrd.h> +#include <linux/module.h> #include <linux/of.h> #include <linux/of_fdt.h> #include <linux/string.h> #include <linux/errno.h> +#include <linux/slab.h> #ifdef CONFIG_PPC #include <asm/machdep.h> @@ -312,6 +314,94 @@ unsigned long unflatten_dt_node(struct boot_param_header *blob, return mem; } +/** + * __unflatten_device_tree - create tree of device_nodes from flat blob + * + * unflattens a device-tree, creating the + * tree of struct device_node. It also fills the "name" and "type" + * pointers of the nodes so the normal device-tree walking functions + * can be used. + * @blob: The blob to expand + * @mynodes: The device_node tree created by the call + * @dt_alloc: An allocator that provides a virtual address to memory + * for the resulting tree + */ +void __unflatten_device_tree(struct boot_param_header *blob, + struct device_node **mynodes, + void * (*dt_alloc)(u64 size, u64 align)) +{ + unsigned long start, mem, size; + struct device_node **allnextp = mynodes; + + pr_debug(" -> unflatten_device_tree()\n"); + + if (!blob) { + pr_debug("No device tree pointer\n"); + return; + } + + pr_debug("Unflattening device tree:\n"); + pr_debug("magic: %08x\n", be32_to_cpu(blob->magic)); + pr_debug("size: %08x\n", be32_to_cpu(blob->totalsize)); + pr_debug("version: %08x\n", be32_to_cpu(blob->version)); + + if (be32_to_cpu(blob->magic) != OF_DT_HEADER) { + pr_err("Invalid device tree blob header\n"); + return; + } + + /* First pass, scan for size */ + start = ((unsigned long)blob) + + be32_to_cpu(blob->off_dt_struct); + size = unflatten_dt_node(blob, 0, &start, NULL, NULL, 0); + size = (size | 3) + 1; + + pr_debug(" size is %lx, allocating...\n", size); + + /* Allocate memory for the expanded device tree */ + mem = (unsigned long) + dt_alloc(size + 4, __alignof__(struct device_node)); + + ((__be32 *)mem)[size / 4] = cpu_to_be32(0xdeadbeef); + + pr_debug(" unflattening %lx...\n", mem); + + /* Second pass, do actual unflattening */ + start = ((unsigned long)blob) + + be32_to_cpu(blob->off_dt_struct); + unflatten_dt_node(blob, mem, &start, NULL, &allnextp, 0); + if (be32_to_cpup((__be32 *)start) != OF_DT_END) + pr_warning("Weird tag at end of tree: %08x\n", *((u32 *)start)); + if (be32_to_cpu(((__be32 *)mem)[size / 4]) != 0xdeadbeef) + pr_warning("End of tree marker overwritten: %08x\n", + be32_to_cpu(((__be32 *)mem)[size / 4])); + *allnextp = NULL; + + pr_debug(" <- unflatten_device_tree()\n"); +} + +static void *kernel_tree_alloc(u64 size, u64 align) +{ + return kzalloc(size, GFP_KERNEL); +} + +/** + * of_fdt_unflatten_tree - create tree of device_nodes from flat blob + * + * unflattens the device-tree passed by the firmware, creating the + * tree of struct device_node. It also fills the "name" and "type" + * pointers of the nodes so the normal device-tree walking functions + * can be used. + */ +void of_fdt_unflatten_tree(unsigned long *blob, + struct device_node **mynodes) +{ + struct boot_param_header *device_tree = + (struct boot_param_header *)blob; + __unflatten_device_tree(device_tree, mynodes, &kernel_tree_alloc); +} +EXPORT_SYMBOL_GPL(of_fdt_unflatten_tree); + /* Everything below here references initial_boot_params directly. */ int __initdata dt_root_addr_cells; int __initdata dt_root_size_cells; @@ -569,6 +659,12 @@ int __init early_init_dt_scan_chosen(unsigned long node, const char *uname, return 1; } +static void *__init early_device_tree_alloc(u64 size, u64 align) +{ + unsigned long mem = early_init_dt_alloc_memory_arch(size, align); + return __va(mem); +} + /** * unflatten_device_tree - create tree of device_nodes from flat blob * @@ -579,62 +675,13 @@ int __init early_init_dt_scan_chosen(unsigned long node, const char *uname, */ void __init unflatten_device_tree(void) { - unsigned long start, mem, size; - struct device_node **allnextp = &allnodes; - - pr_debug(" -> unflatten_device_tree()\n"); - - if (!initial_boot_params) { - pr_debug("No device tree pointer\n"); - return; - } - - pr_debug("Unflattening device tree:\n"); - pr_debug("magic: %08x\n", be32_to_cpu(initial_boot_params->magic)); - pr_debug("size: %08x\n", be32_to_cpu(initial_boot_params->totalsize)); - pr_debug("version: %08x\n", be32_to_cpu(initial_boot_params->version)); - - if (be32_to_cpu(initial_boot_params->magic) != OF_DT_HEADER) { - pr_err("Invalid device tree blob header\n"); - return; - } - - /* First pass, scan for size */ - start = ((unsigned long)initial_boot_params) + - be32_to_cpu(initial_boot_params->off_dt_struct); - size = unflatten_dt_node(initial_boot_params, 0, &start, - NULL, NULL, 0); - size = (size | 3) + 1; - - pr_debug(" size is %lx, allocating...\n", size); - - /* Allocate memory for the expanded device tree */ - mem = early_init_dt_alloc_memory_arch(size + 4, - __alignof__(struct device_node)); - mem = (unsigned long) __va(mem); - - ((__be32 *)mem)[size / 4] = cpu_to_be32(0xdeadbeef); - - pr_debug(" unflattening %lx...\n", mem); - - /* Second pass, do actual unflattening */ - start = ((unsigned long)initial_boot_params) + - be32_to_cpu(initial_boot_params->off_dt_struct); - unflatten_dt_node(initial_boot_params, mem, &start, - NULL, &allnextp, 0); - if (be32_to_cpup((__be32 *)start) != OF_DT_END) - pr_warning("Weird tag at end of tree: %08x\n", *((u32 *)start)); - if (be32_to_cpu(((__be32 *)mem)[size / 4]) != 0xdeadbeef) - pr_warning("End of tree marker overwritten: %08x\n", - be32_to_cpu(((__be32 *)mem)[size / 4])); - *allnextp = NULL; + __unflatten_device_tree(initial_boot_params, &allnodes, + early_device_tree_alloc); /* Get pointer to OF "/chosen" node for use everywhere */ of_chosen = of_find_node_by_path("/chosen"); if (of_chosen == NULL) of_chosen = of_find_node_by_path("/chosen@0"); - - pr_debug(" <- unflatten_device_tree()\n"); } #endif /* CONFIG_OF_EARLY_FLATTREE */ |