1*91f16700Schasinglulu /* 2*91f16700Schasinglulu * Copyright (c) 2018-2023, Arm Limited and Contributors. All rights reserved. 3*91f16700Schasinglulu * 4*91f16700Schasinglulu * SPDX-License-Identifier: BSD-3-Clause 5*91f16700Schasinglulu */ 6*91f16700Schasinglulu 7*91f16700Schasinglulu /* Helper functions to offer easier navigation of Device Tree Blob */ 8*91f16700Schasinglulu 9*91f16700Schasinglulu #ifndef FDT_WRAPPERS_H 10*91f16700Schasinglulu #define FDT_WRAPPERS_H 11*91f16700Schasinglulu 12*91f16700Schasinglulu #include <libfdt_env.h> 13*91f16700Schasinglulu #include <libfdt.h> 14*91f16700Schasinglulu 15*91f16700Schasinglulu /* Number of cells, given total length in bytes. Each cell is 4 bytes long */ 16*91f16700Schasinglulu #define NCELLS(len) ((len) / 4U) 17*91f16700Schasinglulu 18*91f16700Schasinglulu int fdt_read_uint32(const void *dtb, int node, const char *prop_name, 19*91f16700Schasinglulu uint32_t *value); 20*91f16700Schasinglulu uint32_t fdt_read_uint32_default(const void *dtb, int node, 21*91f16700Schasinglulu const char *prop_name, uint32_t dflt_value); 22*91f16700Schasinglulu int fdt_read_uint64(const void *dtb, int node, const char *prop_name, 23*91f16700Schasinglulu uint64_t *value); 24*91f16700Schasinglulu int fdt_read_uint32_array(const void *dtb, int node, const char *prop_name, 25*91f16700Schasinglulu unsigned int cells, uint32_t *value); 26*91f16700Schasinglulu int fdtw_read_string(const void *dtb, int node, const char *prop, 27*91f16700Schasinglulu char *str, size_t size); 28*91f16700Schasinglulu int fdtw_read_uuid(const void *dtb, int node, const char *prop, 29*91f16700Schasinglulu unsigned int length, uint8_t *uuid); 30*91f16700Schasinglulu int fdtw_write_inplace_cells(void *dtb, int node, const char *prop, 31*91f16700Schasinglulu unsigned int cells, void *value); 32*91f16700Schasinglulu int fdtw_read_bytes(const void *dtb, int node, const char *prop, 33*91f16700Schasinglulu unsigned int length, void *value); 34*91f16700Schasinglulu int fdtw_write_inplace_bytes(void *dtb, int node, const char *prop, 35*91f16700Schasinglulu unsigned int length, const void *data); 36*91f16700Schasinglulu int fdt_get_reg_props_by_index(const void *dtb, int node, int index, 37*91f16700Schasinglulu uintptr_t *base, size_t *size); 38*91f16700Schasinglulu int fdt_get_reg_props_by_name(const void *dtb, int node, const char *name, 39*91f16700Schasinglulu uintptr_t *base, size_t *size); 40*91f16700Schasinglulu int fdt_get_stdout_node_offset(const void *dtb); 41*91f16700Schasinglulu 42*91f16700Schasinglulu uint64_t fdtw_translate_address(const void *dtb, int bus_node, 43*91f16700Schasinglulu uint64_t base_address); 44*91f16700Schasinglulu 45*91f16700Schasinglulu int fdtw_for_each_cpu(const void *fdt, 46*91f16700Schasinglulu int (*callback)(const void *dtb, int node, uintptr_t mpidr)); 47*91f16700Schasinglulu 48*91f16700Schasinglulu int fdtw_find_or_add_subnode(void *fdt, int parentoffset, const char *name); 49*91f16700Schasinglulu 50*91f16700Schasinglulu static inline uint32_t fdt_blob_size(const void *dtb) 51*91f16700Schasinglulu { 52*91f16700Schasinglulu const uint32_t *dtb_header = (const uint32_t *)dtb; 53*91f16700Schasinglulu 54*91f16700Schasinglulu return fdt32_to_cpu(dtb_header[1]); 55*91f16700Schasinglulu } 56*91f16700Schasinglulu 57*91f16700Schasinglulu static inline bool fdt_node_is_enabled(const void *fdt, int node) 58*91f16700Schasinglulu { 59*91f16700Schasinglulu int len; 60*91f16700Schasinglulu const void *prop = fdt_getprop(fdt, node, "status", &len); 61*91f16700Schasinglulu 62*91f16700Schasinglulu /* A non-existing status property means the device is enabled. */ 63*91f16700Schasinglulu return (prop == NULL) || (len == 5 && strcmp((const char *)prop, 64*91f16700Schasinglulu "okay") == 0); 65*91f16700Schasinglulu } 66*91f16700Schasinglulu 67*91f16700Schasinglulu #define fdt_for_each_compatible_node(dtb, node, compatible_str) \ 68*91f16700Schasinglulu for (node = fdt_node_offset_by_compatible(dtb, -1, compatible_str); \ 69*91f16700Schasinglulu node >= 0; \ 70*91f16700Schasinglulu node = fdt_node_offset_by_compatible(dtb, node, compatible_str)) 71*91f16700Schasinglulu 72*91f16700Schasinglulu #endif /* FDT_WRAPPERS_H */ 73