of_fdt.h
/*
* Definitions for working with the Flattened Device Tree data format
*
* Copyright 2009 Benjamin Herrenschmidt, IBM Corp
* benh@kernel.crashing.org
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*/
#ifndef _LINUX_OF_FDT_H
#define _LINUX_OF_FDT_H
#include <linux/types.h>
#include <linux/init.h>
/* Definitions used by the flattened device tree */
#define OF_DT_HEADER 0xd00dfeed /* marker */
#define OF_DT_BEGIN_NODE 0x1 /* Start of node, full name */
#define OF_DT_END_NODE 0x2 /* End node */
#define OF_DT_PROP 0x3 /* Property: name off, size,
* content */
#define OF_DT_NOP 0x4 /* nop */
#define OF_DT_END 0x9
#define OF_DT_VERSION 0x10
#ifndef __ASSEMBLY__
/*
* This is what gets passed to the kernel by prom_init or kexec
*
* The dt struct contains the device tree structure, full pathes and
* property contents. The dt strings contain a separate block with just
* the strings for the property names, and is fully page aligned and
* self contained in a page, so that it can be kept around by the kernel,
* each property name appears only once in this page (cheap compression)
*
* the mem_rsvmap contains a map of reserved ranges of physical memory,
* passing it here instead of in the device-tree itself greatly simplifies
* the job of everybody. It's just a list of u64 pairs (base/size) that
* ends when size is 0
*/
struct boot_param_header {
__be32 magic; /* magic word OF_DT_HEADER */
__be32 totalsize; /* total size of DT block */
__be32 off_dt_struct; /* offset to structure */
__be32 off_dt_strings; /* offset to strings */
__be32 off_mem_rsvmap; /* offset to memory reserve map */
__be32 version; /* format version */
__be32 last_comp_version; /* last compatible version */
/* version 2 fields below */
__be32 boot_cpuid_phys; /* Physical CPU id we're booting on */
/* version 3 fields below */
__be32 dt_strings_size; /* size of the DT strings block */
/* version 17 fields below */
__be32 dt_struct_size; /* size of the DT structure block */
};
#if defined(CONFIG_OF_FLATTREE)
struct device_node;
/* For scanning an arbitrary device-tree at any time */
extern char *of_fdt_get_string(struct boot_param_header *blob, u32 offset);
extern void *of_fdt_get_property(struct boot_param_header *blob,
unsigned long node,
const char *name,
unsigned long *size);
extern int of_fdt_is_compatible(struct boot_param_header *blob,
unsigned long node,
const char *compat);
extern int of_fdt_match(struct boot_param_header *blob, unsigned long node,
const char *const *compat);
extern void of_fdt_unflatten_tree(unsigned long *blob,
struct device_node **mynodes);
/* TBD: Temporary export of fdt globals - remove when code fully merged */
extern int __initdata dt_root_addr_cells;
extern int __initdata dt_root_size_cells;
extern struct boot_param_header *initial_boot_params;
/* For scanning the flat device-tree at boot time */
extern char *find_flat_dt_string(u32 offset);
extern int of_scan_flat_dt(int (*it)(unsigned long node, const char *uname,
int depth, void *data),
void *data);
extern void *of_get_flat_dt_prop(unsigned long node, const char *name,
unsigned long *size);
extern int of_flat_dt_is_compatible(unsigned long node, const char *name);
extern int of_flat_dt_match(unsigned long node, const char *const *matches);
extern unsigned long of_get_flat_dt_root(void);
extern int early_init_dt_scan_chosen(unsigned long node, const char *uname,
int depth, void *data);
extern void early_init_dt_check_for_initrd(unsigned long node);
extern int early_init_dt_scan_memory(unsigned long node, const char *uname,
int depth, void *data);
extern void early_init_dt_add_memory_arch(u64 base, u64 size);
extern void * early_init_dt_alloc_memory_arch(u64 size, u64 align);
extern u64 dt_mem_next_cell(int s, __be32 **cellp);
/*
* If BLK_DEV_INITRD, the fdt early init code will call this function,
* to be provided by the arch code. start and end are specified as
* physical addresses.
*/
#ifdef CONFIG_BLK_DEV_INITRD
extern void early_init_dt_setup_initrd_arch(unsigned long start,
unsigned long end);
#endif
/* Early flat tree scan hooks */
extern int early_init_dt_scan_root(unsigned long node, const char *uname,
int depth, void *data);
/* Other Prototypes */
extern void unflatten_device_tree(void);
extern void early_init_devtree(void *);
#else /* CONFIG_OF_FLATTREE */
static inline void unflatten_device_tree(void) {}
#endif /* CONFIG_OF_FLATTREE */
#endif /* __ASSEMBLY__ */
#endif /* _LINUX_OF_FDT_H */