libfdt: Import libfdt source (1 of 2)

This adds the applicable libfdt source files (unmodified) and a README
to explain where the source came from.
diff --git a/include/fdt.h b/include/fdt.h
new file mode 100644
index 0000000..e00559a
--- /dev/null
+++ b/include/fdt.h
@@ -0,0 +1,60 @@
+#ifndef _FDT_H
+#define _FDT_H
+
+#ifndef __ASSEMBLY__
+
+struct fdt_header {
+	uint32_t magic;                  /* magic word FDT_MAGIC */
+	uint32_t totalsize;              /* total size of DT block */
+	uint32_t off_dt_struct;          /* offset to structure */
+	uint32_t off_dt_strings;         /* offset to strings */
+	uint32_t off_mem_rsvmap;         /* offset to memory reserve map */
+	uint32_t version;                /* format version */
+	uint32_t last_comp_version;      /* last compatible version */
+
+        /* version 2 fields below */
+	uint32_t boot_cpuid_phys;        /* Which physical CPU id we're
+					    booting on */
+	/* version 3 fields below */
+        uint32_t size_dt_strings;        /* size of the strings block */
+
+	/* version 17 fields below */
+	uint32_t size_dt_struct;         /* size of the structure block */
+};
+
+struct fdt_reserve_entry {
+	uint64_t address;
+	uint64_t size;
+};
+
+struct fdt_node_header {
+	uint32_t tag;
+	char name[0];
+};
+
+struct fdt_property {
+	uint32_t tag;
+	uint32_t len;
+	uint32_t nameoff;
+	char data[0];
+};
+
+#endif /* !__ASSEMBLY */
+
+#define FDT_MAGIC	0xd00dfeed      /* 4: version, 4: total size */
+#define FDT_TAGSIZE	sizeof(uint32_t)
+
+#define FDT_BEGIN_NODE	0x1             /* Start node: full name */
+#define FDT_END_NODE	0x2             /* End node */
+#define FDT_PROP	0x3             /* Property: name off,
+					   size, content */
+#define FDT_NOP		0x4		/* nop */
+#define FDT_END		0x9
+
+#define FDT_V1_SIZE	(7*sizeof(uint32_t))
+#define FDT_V2_SIZE	(FDT_V1_SIZE + sizeof(uint32_t))
+#define FDT_V3_SIZE	(FDT_V2_SIZE + sizeof(uint32_t))
+#define FDT_V16_SIZE	FDT_V3_SIZE
+#define FDT_V17_SIZE	(FDT_V16_SIZE + sizeof(uint32_t))
+
+#endif /* _FDT_H */
diff --git a/include/libfdt.h b/include/libfdt.h
new file mode 100644
index 0000000..acdc72e
--- /dev/null
+++ b/include/libfdt.h
@@ -0,0 +1,135 @@
+#ifndef _LIBFDT_H
+#define _LIBFDT_H
+/*
+ * libfdt - Flat Device Tree manipulation
+ * Copyright (C) 2006 David Gibson, IBM Corporation.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <fdt.h>
+#include <libfdt_env.h>
+
+#define FDT_FIRST_SUPPORTED_VERSION	0x10
+#define FDT_LAST_SUPPORTED_VERSION	0x11
+
+/* Error codes: informative error codes */
+#define FDT_ERR_NOTFOUND	1
+#define FDT_ERR_EXISTS		2
+#define FDT_ERR_NOSPACE		3
+
+/* Error codes: codes for bad parameters */
+#define FDT_ERR_BADOFFSET	4
+#define FDT_ERR_BADPATH		5
+#define FDT_ERR_BADSTATE	6
+
+/* Error codes: codes for bad device tree blobs */
+#define FDT_ERR_TRUNCATED	7
+#define FDT_ERR_BADMAGIC	8
+#define FDT_ERR_BADVERSION	9
+#define FDT_ERR_BADSTRUCTURE	10
+#define FDT_ERR_BADLAYOUT	11
+
+#define FDT_ERR_MAX		11
+
+#define fdt_get_header(fdt, field) \
+	(fdt32_to_cpu(((struct fdt_header *)(fdt))->field))
+#define fdt_magic(fdt) 			(fdt_get_header(fdt, magic))
+#define fdt_totalsize(fdt)		(fdt_get_header(fdt, totalsize))
+#define fdt_off_dt_struct(fdt)		(fdt_get_header(fdt, off_dt_struct))
+#define fdt_off_dt_strings(fdt)		(fdt_get_header(fdt, off_dt_strings))
+#define fdt_off_mem_rsvmap(fdt)		(fdt_get_header(fdt, off_mem_rsvmap))
+#define fdt_version(fdt)		(fdt_get_header(fdt, version))
+#define fdt_last_comp_version(fdt) 	(fdt_get_header(fdt, last_comp_version))
+#define fdt_boot_cpuid_phys(fdt) 	(fdt_get_header(fdt, boot_cpuid_phys))
+#define fdt_size_dt_strings(fdt) 	(fdt_get_header(fdt, size_dt_strings))
+#define fdt_size_dt_struct(fdt)		(fdt_get_header(fdt, size_dt_struct))
+
+#define fdt_set_header(fdt, field, val) \
+	((struct fdt_header *)(fdt))->field = cpu_to_fdt32(val)
+
+void *fdt_offset_ptr(const void *fdt, int offset, int checklen);
+
+#define fdt_offset_ptr_typed(fdt, offset, var) \
+	((typeof(var))(fdt_offset_ptr((fdt), (offset), sizeof(*(var)))))
+
+int fdt_move(const void *fdt, void *buf, int bufsize);
+
+/* Read-only functions */
+char *fdt_string(const void *fdt, int stroffset);
+
+int fdt_subnode_offset_namelen(const void *fdt, int parentoffset,
+			       const char *name, int namelen);
+int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);
+
+int fdt_path_offset(const void *fdt, const char *path);
+
+struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset,
+				      const char *name, int *lenp);
+void *fdt_getprop(const void *fdt, int nodeoffset,
+		  const char *name, int *lenp);
+
+/* Write-in-place functions */
+int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
+			const void *val, int len);
+
+#define fdt_setprop_inplace_typed(fdt, nodeoffset, name, val) \
+	({ \
+		typeof(val) x = val; \
+		fdt_setprop_inplace(fdt, nodeoffset, name, &x, sizeof(x)); \
+	})
+
+int fdt_nop_property(void *fdt, int nodeoffset, const char *name);
+int fdt_nop_node(void *fdt, int nodeoffset);
+
+/* Sequential-write functions */
+int fdt_create(void *buf, int bufsize);
+int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size);
+int fdt_finish_reservemap(void *fdt);
+int fdt_begin_node(void *fdt, const char *name);
+int fdt_property(void *fdt, const char *name, const void *val, int len);
+#define fdt_property_typed(fdt, name, val) \
+	({ \
+		typeof(val) x = (val); \
+		fdt_property((fdt), (name), &x, sizeof(x)); \
+	})
+#define fdt_property_string(fdt, name, str) \
+	fdt_property(fdt, name, str, strlen(str)+1)
+int fdt_end_node(void *fdt);
+int fdt_finish(void *fdt);
+
+/* Read-write functions */
+int fdt_open_into(void *fdt, void *buf, int bufsize);
+int fdt_pack(void *fdt);
+
+int fdt_setprop(void *fdt, int nodeoffset, const char *name,
+		const void *val, int len);
+#define fdt_setprop_typed(fdt, nodeoffset, name, val) \
+	({ \
+		typeof(val) x = (val); \
+		fdt_setprop((fdt), (nodeoffset), (name), &x, sizeof(x)); \
+	})
+#define fdt_setprop_string(fdt, nodeoffset, name, str) \
+	fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
+int fdt_delprop(void *fdt, int nodeoffset, const char *name);
+int fdt_add_subnode_namelen(void *fdt, int parentoffset,
+			    const char *name, int namelen);
+int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
+int fdt_del_node(void *fdt, int nodeoffset);
+
+/* Extra functions */
+const char *fdt_strerror(int errval);
+
+#endif /* _LIBFDT_H */
diff --git a/include/libfdt_env.h b/include/libfdt_env.h
new file mode 100644
index 0000000..59f2536
--- /dev/null
+++ b/include/libfdt_env.h
@@ -0,0 +1,22 @@
+#ifndef _LIBFDT_ENV_H
+#define _LIBFDT_ENV_H
+
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
+#include <endian.h>
+#include <byteswap.h>
+
+#if __BYTE_ORDER == __BIG_ENDIAN
+#define fdt32_to_cpu(x)		(x)
+#define cpu_to_fdt32(x)		(x)
+#define fdt64_to_cpu(x)		(x)
+#define cpu_to_fdt64(x)		(x)
+#else
+#define fdt32_to_cpu(x)		(bswap_32((x)))
+#define cpu_to_fdt32(x)		(bswap_32((x)))
+#define fdt64_to_cpu(x)		(bswap_64((x)))
+#define cpu_to_fdt64(x)		(bswap_64((x)))
+#endif
+
+#endif /* _LIBFDT_ENV_H */