freebsd-dev/stand/kboot/kbootfdt.c
Warner Losh 111610316e kboot: Allow loading fdt from different sources
Linux has /sys/firmware/fdt and /proc/device-tree to publish the dtb for
the system. The former has it all in one file, while the latter breaks
it out. Prefer the former since it's the more modern interface, but
retain both since I don't have a PS3 to test to see if its kernel is new
enough for /sys/firmware or not.

In addition, do the proper fixup.

Sponsored by:		Netflix
2022-12-08 22:07:52 -07:00

138 lines
3.9 KiB
C

/*-
* Copyright (C) 2014 Nathan Whitehorn
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <fdt_platform.h>
#include <libfdt.h>
#include "bootstrap.h"
#include "host_syscall.h"
#include "kboot.h"
static void
add_node_to_fdt(void *buffer, const char *path, int fdt_offset)
{
int child_offset, fd, pfd, error, dentsize;
char subpath[512];
void *propbuf;
ssize_t proplen;
char dents[2048];
struct host_dirent64 *dent;
int d_type;
fd = host_open(path, O_RDONLY, 0);
while (1) {
dentsize = host_getdents64(fd, dents, sizeof(dents));
if (dentsize <= 0)
break;
for (dent = (struct host_dirent64 *)dents;
(char *)dent < dents + dentsize;
dent = (struct host_dirent64 *)((void *)dent + dent->d_reclen)) {
sprintf(subpath, "%s/%s", path, dent->d_name);
if (strcmp(dent->d_name, ".") == 0 ||
strcmp(dent->d_name, "..") == 0)
continue;
d_type = dent->d_type;
if (d_type == HOST_DT_DIR) {
child_offset = fdt_add_subnode(buffer, fdt_offset,
dent->d_name);
if (child_offset < 0) {
printf("Error %d adding node %s/%s, skipping\n",
child_offset, path, dent->d_name);
continue;
}
add_node_to_fdt(buffer, subpath, child_offset);
} else {
propbuf = malloc(1024);
proplen = 0;
pfd = host_open(subpath, O_RDONLY, 0);
if (pfd > 0) {
proplen = host_read(pfd, propbuf, 1024);
host_close(pfd);
}
error = fdt_setprop(buffer, fdt_offset, dent->d_name,
propbuf, proplen);
free(propbuf);
if (error)
printf("Error %d adding property %s to "
"node %d\n", error, dent->d_name,
fdt_offset);
}
}
}
host_close(fd);
}
int
fdt_platform_load_dtb(void)
{
void *buffer;
size_t buflen = 409600;
int fd;
/*
* Should load /sys/firmware/fdt if it exists, otherwise we walk the
* tree from /proc/device-tree. The former is much easier than the
* latter and also the newer interface. But as long as we support the
* PS3 boot, we'll need the latter due to that kernel's age. It likely
* would be better to script the decision between the two, but that
* turns out to be tricky...
*/
buffer = malloc(buflen);
fd = host_open("/sys/firmware/fdt", O_RDONLY, 0);
if (fd != -1) {
buflen = host_read(fd, buffer, buflen);
close(fd);
} else {
fdt_create_empty_tree(buffer, buflen);
add_node_to_fdt(buffer, "/proc/device-tree",
fdt_path_offset(buffer, "/"));
}
fdt_arch_fixups(buffer);
fdt_pack(buffer);
fdt_load_dtb_addr(buffer);
free(buffer);
return (0);
}
void
fdt_platform_load_overlays(void)
{
fdt_load_dtb_overlays(NULL);
}
void
fdt_platform_fixups(void)
{
fdt_apply_overlays();
}