u-boot/lib/fdtdec.c

148 lines
3.9 KiB
C

/*
* Copyright (c) 2011 The Chromium OS Authors.
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <common.h>
#include <serial.h>
#include <libfdt.h>
#include <fdtdec.h>
DECLARE_GLOBAL_DATA_PTR;
/*
* Here are the type we know about. One day we might allow drivers to
* register. For now we just put them here. The COMPAT macro allows us to
* turn this into a sparse list later, and keeps the ID with the name.
*/
#define COMPAT(id, name) name
static const char * const compat_names[COMPAT_COUNT] = {
};
/**
* Look in the FDT for an alias with the given name and return its node.
*
* @param blob FDT blob
* @param name alias name to look up
* @return node offset if found, or an error code < 0 otherwise
*/
static int find_alias_node(const void *blob, const char *name)
{
const char *path;
int alias_node;
debug("find_alias_node: %s\n", name);
alias_node = fdt_path_offset(blob, "/aliases");
if (alias_node < 0)
return alias_node;
path = fdt_getprop(blob, alias_node, name, NULL);
if (!path)
return -FDT_ERR_NOTFOUND;
return fdt_path_offset(blob, path);
}
fdt_addr_t fdtdec_get_addr(const void *blob, int node,
const char *prop_name)
{
const fdt_addr_t *cell;
int len;
debug("get_addr: %s\n", prop_name);
cell = fdt_getprop(blob, node, prop_name, &len);
if (cell && (len == sizeof(fdt_addr_t) ||
len == sizeof(fdt_addr_t) * 2))
return fdt_addr_to_cpu(*cell);
return FDT_ADDR_T_NONE;
}
s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
s32 default_val)
{
const s32 *cell;
int len;
debug("get_size: %s\n", prop_name);
cell = fdt_getprop(blob, node, prop_name, &len);
if (cell && len >= sizeof(s32))
return fdt32_to_cpu(cell[0]);
return default_val;
}
int fdtdec_get_is_enabled(const void *blob, int node, int default_val)
{
const char *cell;
cell = fdt_getprop(blob, node, "status", NULL);
if (cell)
return 0 == strcmp(cell, "ok");
return default_val;
}
enum fdt_compat_id fd_dec_lookup(const void *blob, int node)
{
enum fdt_compat_id id;
/* Search our drivers */
for (id = COMPAT_UNKNOWN; id < COMPAT_COUNT; id++)
if (0 == fdt_node_check_compatible(blob, node,
compat_names[id]))
return id;
return COMPAT_UNKNOWN;
}
int fdtdec_next_compatible(const void *blob, int node,
enum fdt_compat_id id)
{
return fdt_node_offset_by_compatible(blob, node, compat_names[id]);
}
int fdtdec_next_alias(const void *blob, const char *name,
enum fdt_compat_id id, int *upto)
{
#define MAX_STR_LEN 20
char str[MAX_STR_LEN + 20];
int node, err;
/* snprintf() is not available */
assert(strlen(name) < MAX_STR_LEN);
sprintf(str, "%.*s%d", MAX_STR_LEN, name, *upto);
(*upto)++;
node = find_alias_node(blob, str);
if (node < 0)
return node;
err = fdt_node_check_compatible(blob, node, compat_names[id]);
if (err < 0)
return err;
return err ? -FDT_ERR_NOTFOUND : node;
}
/*
* This function is a little odd in that it accesses global data. At some
* point if the architecture board.c files merge this will make more sense.
* Even now, it is common code.
*/
int fdtdec_check_fdt(void)
{
/* We must have an fdt */
if (fdt_check_header(gd->fdt_blob))
panic("No valid fdt found - please append one to U-Boot\n"
"binary or define CONFIG_OF_EMBED\n");
return 0;
}