/* * 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 #include /* 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 */ }; /* 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 unsigned long of_get_flat_dt_root(void); extern void early_init_dt_scan_chosen_arch(unsigned long node); 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 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 *); #endif /* __ASSEMBLY__ */ #endif /* _LINUX_OF_FDT_H */