xref: /openbmc/linux/include/linux/of_fdt.h (revision b6dcefde)
1 /*
2  * Definitions for working with the Flattened Device Tree data format
3  *
4  * Copyright 2009 Benjamin Herrenschmidt, IBM Corp
5  * benh@kernel.crashing.org
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License
9  * version 2 as published by the Free Software Foundation.
10  */
11 
12 #ifndef _LINUX_OF_FDT_H
13 #define _LINUX_OF_FDT_H
14 
15 #include <linux/types.h>
16 #include <linux/init.h>
17 
18 /* Definitions used by the flattened device tree */
19 #define OF_DT_HEADER		0xd00dfeed	/* marker */
20 #define OF_DT_BEGIN_NODE	0x1		/* Start of node, full name */
21 #define OF_DT_END_NODE		0x2		/* End node */
22 #define OF_DT_PROP		0x3		/* Property: name off, size,
23 						 * content */
24 #define OF_DT_NOP		0x4		/* nop */
25 #define OF_DT_END		0x9
26 
27 #define OF_DT_VERSION		0x10
28 
29 #ifndef __ASSEMBLY__
30 /*
31  * This is what gets passed to the kernel by prom_init or kexec
32  *
33  * The dt struct contains the device tree structure, full pathes and
34  * property contents. The dt strings contain a separate block with just
35  * the strings for the property names, and is fully page aligned and
36  * self contained in a page, so that it can be kept around by the kernel,
37  * each property name appears only once in this page (cheap compression)
38  *
39  * the mem_rsvmap contains a map of reserved ranges of physical memory,
40  * passing it here instead of in the device-tree itself greatly simplifies
41  * the job of everybody. It's just a list of u64 pairs (base/size) that
42  * ends when size is 0
43  */
44 struct boot_param_header {
45 	u32	magic;			/* magic word OF_DT_HEADER */
46 	u32	totalsize;		/* total size of DT block */
47 	u32	off_dt_struct;		/* offset to structure */
48 	u32	off_dt_strings;		/* offset to strings */
49 	u32	off_mem_rsvmap;		/* offset to memory reserve map */
50 	u32	version;		/* format version */
51 	u32	last_comp_version;	/* last compatible version */
52 	/* version 2 fields below */
53 	u32	boot_cpuid_phys;	/* Physical CPU id we're booting on */
54 	/* version 3 fields below */
55 	u32	dt_strings_size;	/* size of the DT strings block */
56 	/* version 17 fields below */
57 	u32	dt_struct_size;		/* size of the DT structure block */
58 };
59 
60 /* For scanning the flat device-tree at boot time */
61 extern int __init of_scan_flat_dt(int (*it)(unsigned long node,
62 					    const char *uname, int depth,
63 					    void *data),
64 				  void *data);
65 extern void __init *of_get_flat_dt_prop(unsigned long node, const char *name,
66 					unsigned long *size);
67 extern int __init of_flat_dt_is_compatible(unsigned long node,
68 					   const char *name);
69 extern unsigned long __init of_get_flat_dt_root(void);
70 
71 /* Other Prototypes */
72 extern void finish_device_tree(void);
73 extern void unflatten_device_tree(void);
74 extern void early_init_devtree(void *);
75 extern int machine_is_compatible(const char *compat);
76 extern void print_properties(struct device_node *node);
77 extern int prom_n_intr_cells(struct device_node* np);
78 extern void prom_get_irq_senses(unsigned char *senses, int off, int max);
79 extern int prom_add_property(struct device_node* np, struct property* prop);
80 extern int prom_remove_property(struct device_node *np, struct property *prop);
81 extern int prom_update_property(struct device_node *np,
82 				struct property *newprop,
83 				struct property *oldprop);
84 
85 #endif /* __ASSEMBLY__ */
86 #endif /* _LINUX_OF_FDT_H */
87