From eff82c45c589b42061344039d5f2efc8ad7c52df Mon Sep 17 00:00:00 2001 From: stefan Date: Fri, 21 Apr 2023 19:53:04 -0400 Subject: libfdt port and the required libc functions --- lib/libfdt/fdt_sw.c | 384 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 384 insertions(+) create mode 100644 lib/libfdt/fdt_sw.c (limited to 'lib/libfdt/fdt_sw.c') diff --git a/lib/libfdt/fdt_sw.c b/lib/libfdt/fdt_sw.c new file mode 100644 index 0000000..4c569ee --- /dev/null +++ b/lib/libfdt/fdt_sw.c @@ -0,0 +1,384 @@ +// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause) +/* + * libfdt - Flat Device Tree manipulation + * Copyright (C) 2006 David Gibson, IBM Corporation. + */ +#include "libfdt_env.h" + +#include +#include + +#include "libfdt_internal.h" + +static int fdt_sw_probe_(void *fdt) +{ + if (!can_assume(VALID_INPUT)) { + if (fdt_magic(fdt) == FDT_MAGIC) + return -FDT_ERR_BADSTATE; + else if (fdt_magic(fdt) != FDT_SW_MAGIC) + return -FDT_ERR_BADMAGIC; + } + + return 0; +} + +#define FDT_SW_PROBE(fdt) \ + { \ + int err; \ + if ((err = fdt_sw_probe_(fdt)) != 0) \ + return err; \ + } + +/* 'memrsv' state: Initial state after fdt_create() + * + * Allowed functions: + * fdt_add_reservemap_entry() + * fdt_finish_reservemap() [moves to 'struct' state] + */ +static int fdt_sw_probe_memrsv_(void *fdt) +{ + int err = fdt_sw_probe_(fdt); + if (err) + return err; + + if (!can_assume(VALID_INPUT) && fdt_off_dt_strings(fdt) != 0) + return -FDT_ERR_BADSTATE; + return 0; +} + +#define FDT_SW_PROBE_MEMRSV(fdt) \ + { \ + int err; \ + if ((err = fdt_sw_probe_memrsv_(fdt)) != 0) \ + return err; \ + } + +/* 'struct' state: Enter this state after fdt_finish_reservemap() + * + * Allowed functions: + * fdt_begin_node() + * fdt_end_node() + * fdt_property*() + * fdt_finish() [moves to 'complete' state] + */ +static int fdt_sw_probe_struct_(void *fdt) +{ + int err = fdt_sw_probe_(fdt); + if (err) + return err; + + if (!can_assume(VALID_INPUT) && + fdt_off_dt_strings(fdt) != fdt_totalsize(fdt)) + return -FDT_ERR_BADSTATE; + return 0; +} + +#define FDT_SW_PROBE_STRUCT(fdt) \ + { \ + int err; \ + if ((err = fdt_sw_probe_struct_(fdt)) != 0) \ + return err; \ + } + +static inline uint32_t sw_flags(void *fdt) +{ + /* assert: (fdt_magic(fdt) == FDT_SW_MAGIC) */ + return fdt_last_comp_version(fdt); +} + +/* 'complete' state: Enter this state after fdt_finish() + * + * Allowed functions: none + */ + +static void *fdt_grab_space_(void *fdt, size_t len) +{ + unsigned int offset = fdt_size_dt_struct(fdt); + unsigned int spaceleft; + + spaceleft = fdt_totalsize(fdt) - fdt_off_dt_struct(fdt) + - fdt_size_dt_strings(fdt); + + if ((offset + len < offset) || (offset + len > spaceleft)) + return NULL; + + fdt_set_size_dt_struct(fdt, offset + len); + return fdt_offset_ptr_w_(fdt, offset); +} + +int fdt_create_with_flags(void *buf, int bufsize, uint32_t flags) +{ + const int hdrsize = FDT_ALIGN(sizeof(struct fdt_header), + sizeof(struct fdt_reserve_entry)); + void *fdt = buf; + + if (bufsize < hdrsize) + return -FDT_ERR_NOSPACE; + + if (flags & ~FDT_CREATE_FLAGS_ALL) + return -FDT_ERR_BADFLAGS; + + memset(buf, 0, bufsize); + + /* + * magic and last_comp_version keep intermediate state during the fdt + * creation process, which is replaced with the proper FDT format by + * fdt_finish(). + * + * flags should be accessed with sw_flags(). + */ + fdt_set_magic(fdt, FDT_SW_MAGIC); + fdt_set_version(fdt, FDT_LAST_SUPPORTED_VERSION); + fdt_set_last_comp_version(fdt, flags); + + fdt_set_totalsize(fdt, bufsize); + + fdt_set_off_mem_rsvmap(fdt, hdrsize); + fdt_set_off_dt_struct(fdt, fdt_off_mem_rsvmap(fdt)); + fdt_set_off_dt_strings(fdt, 0); + + return 0; +} + +int fdt_create(void *buf, int bufsize) +{ + return fdt_create_with_flags(buf, bufsize, 0); +} + +int fdt_resize(void *fdt, void *buf, int bufsize) +{ + size_t headsize, tailsize; + char *oldtail, *newtail; + + FDT_SW_PROBE(fdt); + + if (bufsize < 0) + return -FDT_ERR_NOSPACE; + + headsize = fdt_off_dt_struct(fdt) + fdt_size_dt_struct(fdt); + tailsize = fdt_size_dt_strings(fdt); + + if (!can_assume(VALID_DTB) && + headsize + tailsize > fdt_totalsize(fdt)) + return -FDT_ERR_INTERNAL; + + if ((headsize + tailsize) > (unsigned)bufsize) + return -FDT_ERR_NOSPACE; + + oldtail = (char *)fdt + fdt_totalsize(fdt) - tailsize; + newtail = (char *)buf + bufsize - tailsize; + + /* Two cases to avoid clobbering data if the old and new + * buffers partially overlap */ + if (buf <= fdt) { + memmove(buf, fdt, headsize); + memmove(newtail, oldtail, tailsize); + } else { + memmove(newtail, oldtail, tailsize); + memmove(buf, fdt, headsize); + } + + fdt_set_totalsize(buf, bufsize); + if (fdt_off_dt_strings(buf)) + fdt_set_off_dt_strings(buf, bufsize); + + return 0; +} + +int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size) +{ + struct fdt_reserve_entry *re; + int offset; + + FDT_SW_PROBE_MEMRSV(fdt); + + offset = fdt_off_dt_struct(fdt); + if ((offset + sizeof(*re)) > fdt_totalsize(fdt)) + return -FDT_ERR_NOSPACE; + + re = (struct fdt_reserve_entry *)((char *)fdt + offset); + re->address = cpu_to_fdt64(addr); + re->size = cpu_to_fdt64(size); + + fdt_set_off_dt_struct(fdt, offset + sizeof(*re)); + + return 0; +} + +int fdt_finish_reservemap(void *fdt) +{ + int err = fdt_add_reservemap_entry(fdt, 0, 0); + + if (err) + return err; + + fdt_set_off_dt_strings(fdt, fdt_totalsize(fdt)); + return 0; +} + +int fdt_begin_node(void *fdt, const char *name) +{ + struct fdt_node_header *nh; + int namelen; + + FDT_SW_PROBE_STRUCT(fdt); + + namelen = strlen(name) + 1; + nh = fdt_grab_space_(fdt, sizeof(*nh) + FDT_TAGALIGN(namelen)); + if (! nh) + return -FDT_ERR_NOSPACE; + + nh->tag = cpu_to_fdt32(FDT_BEGIN_NODE); + memcpy(nh->name, name, namelen); + return 0; +} + +int fdt_end_node(void *fdt) +{ + fdt32_t *en; + + FDT_SW_PROBE_STRUCT(fdt); + + en = fdt_grab_space_(fdt, FDT_TAGSIZE); + if (! en) + return -FDT_ERR_NOSPACE; + + *en = cpu_to_fdt32(FDT_END_NODE); + return 0; +} + +static int fdt_add_string_(void *fdt, const char *s) +{ + char *strtab = (char *)fdt + fdt_totalsize(fdt); + unsigned int strtabsize = fdt_size_dt_strings(fdt); + unsigned int len = strlen(s) + 1; + unsigned int struct_top, offset; + + offset = strtabsize + len; + struct_top = fdt_off_dt_struct(fdt) + fdt_size_dt_struct(fdt); + if (fdt_totalsize(fdt) - offset < struct_top) + return 0; /* no more room :( */ + + memcpy(strtab - offset, s, len); + fdt_set_size_dt_strings(fdt, strtabsize + len); + return -offset; +} + +/* Must only be used to roll back in case of error */ +static void fdt_del_last_string_(void *fdt, const char *s) +{ + int strtabsize = fdt_size_dt_strings(fdt); + int len = strlen(s) + 1; + + fdt_set_size_dt_strings(fdt, strtabsize - len); +} + +static int fdt_find_add_string_(void *fdt, const char *s, int *allocated) +{ + char *strtab = (char *)fdt + fdt_totalsize(fdt); + int strtabsize = fdt_size_dt_strings(fdt); + const char *p; + + *allocated = 0; + + p = fdt_find_string_(strtab - strtabsize, strtabsize, s); + if (p) + return p - strtab; + + *allocated = 1; + + return fdt_add_string_(fdt, s); +} + +int fdt_property_placeholder(void *fdt, const char *name, int len, void **valp) +{ + struct fdt_property *prop; + int nameoff; + int allocated; + + FDT_SW_PROBE_STRUCT(fdt); + + /* String de-duplication can be slow, _NO_NAME_DEDUP skips it */ + if (sw_flags(fdt) & FDT_CREATE_FLAG_NO_NAME_DEDUP) { + allocated = 1; + nameoff = fdt_add_string_(fdt, name); + } else { + nameoff = fdt_find_add_string_(fdt, name, &allocated); + } + if (nameoff == 0) + return -FDT_ERR_NOSPACE; + + prop = fdt_grab_space_(fdt, sizeof(*prop) + FDT_TAGALIGN(len)); + if (! prop) { + if (allocated) + fdt_del_last_string_(fdt, name); + return -FDT_ERR_NOSPACE; + } + + prop->tag = cpu_to_fdt32(FDT_PROP); + prop->nameoff = cpu_to_fdt32(nameoff); + prop->len = cpu_to_fdt32(len); + *valp = prop->data; + return 0; +} + +int fdt_property(void *fdt, const char *name, const void *val, int len) +{ + void *ptr; + int ret; + + ret = fdt_property_placeholder(fdt, name, len, &ptr); + if (ret) + return ret; + memcpy(ptr, val, len); + return 0; +} + +int fdt_finish(void *fdt) +{ + char *p = (char *)fdt; + fdt32_t *end; + int oldstroffset, newstroffset; + uint32_t tag; + int offset, nextoffset; + + FDT_SW_PROBE_STRUCT(fdt); + + /* Add terminator */ + end = fdt_grab_space_(fdt, sizeof(*end)); + if (! end) + return -FDT_ERR_NOSPACE; + *end = cpu_to_fdt32(FDT_END); + + /* Relocate the string table */ + oldstroffset = fdt_totalsize(fdt) - fdt_size_dt_strings(fdt); + newstroffset = fdt_off_dt_struct(fdt) + fdt_size_dt_struct(fdt); + memmove(p + newstroffset, p + oldstroffset, fdt_size_dt_strings(fdt)); + fdt_set_off_dt_strings(fdt, newstroffset); + + /* Walk the structure, correcting string offsets */ + offset = 0; + while ((tag = fdt_next_tag(fdt, offset, &nextoffset)) != FDT_END) { + if (tag == FDT_PROP) { + struct fdt_property *prop = + fdt_offset_ptr_w_(fdt, offset); + int nameoff; + + nameoff = fdt32_to_cpu(prop->nameoff); + nameoff += fdt_size_dt_strings(fdt); + prop->nameoff = cpu_to_fdt32(nameoff); + } + offset = nextoffset; + } + if (nextoffset < 0) + return nextoffset; + + /* Finally, adjust the header */ + fdt_set_totalsize(fdt, newstroffset + fdt_size_dt_strings(fdt)); + + /* And fix up fields that were keeping intermediate state. */ + fdt_set_last_comp_version(fdt, FDT_LAST_COMPATIBLE_VERSION); + fdt_set_magic(fdt, FDT_MAGIC); + + return 0; +} -- cgit v1.2.3