mirror of
https://github.com/torvalds/linux.git
synced 2024-11-14 08:02:07 +00:00
819d281930
Merge common code between PowerPC and MicroBlaze Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Reviewed-by: Wolfram Sang <w.sang@pengutronix.de> Tested-by: Michal Simek <monstr@monstr.eu>
102 lines
2.3 KiB
C
102 lines
2.3 KiB
C
/*
|
|
* Functions for working with the Flattened Device Tree data format
|
|
*
|
|
* Copyright 2009 Benjamin Herrenschmidt, IBM Corp
|
|
* benh@kernel.crashing.org
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* version 2 as published by the Free Software Foundation.
|
|
*/
|
|
|
|
#include <linux/of.h>
|
|
#include <linux/of_fdt.h>
|
|
|
|
struct boot_param_header *initial_boot_params;
|
|
|
|
char *find_flat_dt_string(u32 offset)
|
|
{
|
|
return ((char *)initial_boot_params) +
|
|
initial_boot_params->off_dt_strings + offset;
|
|
}
|
|
|
|
/**
|
|
* of_scan_flat_dt - scan flattened tree blob and call callback on each.
|
|
* @it: callback function
|
|
* @data: context data pointer
|
|
*
|
|
* This function is used to scan the flattened device-tree, it is
|
|
* used to extract the memory information at boot before we can
|
|
* unflatten the tree
|
|
*/
|
|
int __init of_scan_flat_dt(int (*it)(unsigned long node,
|
|
const char *uname, int depth,
|
|
void *data),
|
|
void *data)
|
|
{
|
|
unsigned long p = ((unsigned long)initial_boot_params) +
|
|
initial_boot_params->off_dt_struct;
|
|
int rc = 0;
|
|
int depth = -1;
|
|
|
|
do {
|
|
u32 tag = *((u32 *)p);
|
|
char *pathp;
|
|
|
|
p += 4;
|
|
if (tag == OF_DT_END_NODE) {
|
|
depth--;
|
|
continue;
|
|
}
|
|
if (tag == OF_DT_NOP)
|
|
continue;
|
|
if (tag == OF_DT_END)
|
|
break;
|
|
if (tag == OF_DT_PROP) {
|
|
u32 sz = *((u32 *)p);
|
|
p += 8;
|
|
if (initial_boot_params->version < 0x10)
|
|
p = _ALIGN(p, sz >= 8 ? 8 : 4);
|
|
p += sz;
|
|
p = _ALIGN(p, 4);
|
|
continue;
|
|
}
|
|
if (tag != OF_DT_BEGIN_NODE) {
|
|
pr_err("Invalid tag %x in flat device tree!\n", tag);
|
|
return -EINVAL;
|
|
}
|
|
depth++;
|
|
pathp = (char *)p;
|
|
p = _ALIGN(p + strlen(pathp) + 1, 4);
|
|
if ((*pathp) == '/') {
|
|
char *lp, *np;
|
|
for (lp = NULL, np = pathp; *np; np++)
|
|
if ((*np) == '/')
|
|
lp = np+1;
|
|
if (lp != NULL)
|
|
pathp = lp;
|
|
}
|
|
rc = it(p, pathp, depth, data);
|
|
if (rc != 0)
|
|
break;
|
|
} while (1);
|
|
|
|
return rc;
|
|
}
|
|
|
|
/**
|
|
* of_get_flat_dt_root - find the root node in the flat blob
|
|
*/
|
|
unsigned long __init of_get_flat_dt_root(void)
|
|
{
|
|
unsigned long p = ((unsigned long)initial_boot_params) +
|
|
initial_boot_params->off_dt_struct;
|
|
|
|
while (*((u32 *)p) == OF_DT_NOP)
|
|
p += 4;
|
|
BUG_ON(*((u32 *)p) != OF_DT_BEGIN_NODE);
|
|
p += 4;
|
|
return _ALIGN(p + strlen((char *)p) + 1, 4);
|
|
}
|
|
|