/*
* Procedures for creating, accessing and interpreting the device tree.
*
* Paul Mackerras August 1996.
* Copyright (C) 1996-2005 Paul Mackerras.
*
* Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
* {engebret|bergner}@us.ibm.com
*
* 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.
*/
#include <stdarg.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/threads.h>
#include <linux/spinlock.h>
#include <linux/types.h>
#include <linux/pci.h>
#include <linux/stringify.h>
#include <linux/delay.h>
#include <linux/initrd.h>
#include <linux/bitops.h>
#include <linux/module.h>
#include <linux/kexec.h>
#include <linux/debugfs.h>
#include <linux/irq.h>
#include <linux/lmb.h>
#include <asm/prom.h>
#include <asm/page.h>
#include <asm/processor.h>
#include <asm/irq.h>
#include <linux/io.h>
#include <asm/system.h>
#include <asm/mmu.h>
#include <asm/pgtable.h>
#include <asm/sections.h>
#include <asm/pci-bridge.h>
static int __initdata dt_root_addr_cells;
static int __initdata dt_root_size_cells;
typedef u32 cell_t;
static struct boot_param_header *initial_boot_params;
/* export that to outside world */
struct device_node *of_chosen;
static inline char *find_flat_dt_string(u32 offset)
{
return ((char *)initial_boot_params) +
initial_boot_params->off_dt_strings + offset;
}
/**
* This function is used to scan the flattened device-tree, it is
* used to extract the memory informations 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) {
printk(KERN_WARNING "Invalid tag %x scanning flattened"
" 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;
}
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);
}
/**
* This function can be used within scan_flattened_dt callback to get
* access to properties
*/
void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
unsigned long *size)
{
unsigned long p = node;
do {
u32 tag = *((u32 *)p);
u32 sz, noff;
const char *nstr;
p += 4;
if (tag == OF_DT_NOP)
continue;
if (tag != OF_DT_PROP)
return NULL;
sz = *((u32 *)p);
noff = *((u32 *)(p + 4));
p += 8;
if (initial_boot_params->version < 0x10)
p = _ALIGN(p, sz >= 8 ? 8 : 4);
nstr = find_flat_dt_string(noff);
if (nstr == NULL) {
printk(KERN_WARNING "Can't find property index"
" name !\n");
return NULL;
}
if (strcmp(name, nstr) == 0) {
if (size)
*size = sz;
return (void *)p;
}
p += sz;
p = _ALIGN(p, 4);
} while (1);
}
int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
{
const char *cp;
unsigned long cplen, l;
cp = of_get_flat_dt_prop(node, "compatible", &cplen);
if (cp == NULL)
return 0;
while (cplen > 0) {
if (strncasecmp(cp, compat, strlen(compat)) == 0)
return 1;
l = strlen(cp) + 1;
cp += l;
cplen -= l;
}
return 0;
}
static void *__init unflatten_dt_alloc(unsigned long *mem, unsigned long size,
unsigned long align)
{
void *res;
*mem = _ALIGN(*mem, align);
res = (void *)*mem;
*mem += size;
return res;
}
static unsigned long __init unflatten_dt_node(unsigned long mem,
unsigned long *p,
struct device_node *dad,
struct device_node ***allnextpp,
unsigned long fpsize)
{
struct device_node *np;
struct property *pp, **prev_pp = NULL;
char *pathp;
u32 tag;
unsigned int l, allocl;
int has_name = 0;
int new_format = 0;
tag = *((u32 *)(*p));
if (tag != OF_DT_BEGIN_NODE) {
printk("Weird tag at start of node: %x\n", tag);
return mem;
}
*p += 4;
pathp = (char *)*p;
l = allocl = strlen(pathp) + 1;
*p = _ALIGN(*p + l, 4);
/* version 0x10 has a more compact unit name here instead of the full
* path. we accumulate the full path size using "fpsize", we'll rebuild
* it later. We detect this because the first character of the name is
* not '/'.
*/
if ((*pathp) != '/') {
new_format = 1;
if (fpsize == 0) {
/* root node: special case. fpsize accounts for path
* plus terminating zero. root node only has '/', so
* fpsize should be 2, but we want to avoid the first
* level nodes to have two '/' so we use fpsize 1 here
*/
fpsize = 1;
allocl = 2;
} else {
/* account for '/' and path size minus terminal 0
* already in 'l'
*/
fpsize += l;
allocl = fpsize;
}
}
np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl,
__alignof__(struct device_node));
if (allnextpp) {
memset(np, 0, sizeof(*np));
np->full_name = ((char *)np) + sizeof(struct device_node);
if (new_format) {
char *p2 = np->full_name;
/* rebuild full path for new format */
if (dad && dad->parent) {
strcpy(p2, dad->full_name);
#ifdef DEBUG
if ((strlen(p2) + l + 1) != allocl) {
pr_debug("%s: p: %d, l: %d, a: %d\n",
pathp, (int)strlen(p2),
l, allocl);
}
#endif
p2 += strlen(p2);
}
*(p2++) = '/';
memcpy(p2, pathp, l);
} else
memcpy(np->full_name, pathp, l);
prev_pp = &np->properties;
**allnextpp = np;
*allnextpp = &np->allnext;
if (dad != NULL) {
np->parent = dad;
/* we temporarily use the next field as `last_child'*/
if (dad->next == NULL)
dad->child = np;
else
dad->next->sibling = np;
dad->next = np;
}
kref_init(&np->kref);
}
while (1) {
u32 sz, noff;
char *pname;
tag = *((u32 *)(*p));
if (tag == OF_DT_NOP) {
*p += 4;
continue;
}
if (tag != OF_DT_PROP)
break;
*p += 4;
sz = *((u32 *)(*p));
noff = *((u32 *)((*p) + 4));
*p += 8;
if (initial_boot_params->version < 0x10)
*p = _ALIGN(*p, sz >= 8 ? 8 : 4);
pname = find_flat_dt_string(noff);
if (pname == NULL) {
printk(KERN_INFO
"Can't find property name in list !\n");
break;
}
if (strcmp(pname, "name") == 0)
has_name = 1;
l = strlen(pname) + 1;
pp = unflatten_dt_alloc(&mem, sizeof(struct property),
__alignof__(struct property));
if (allnextpp) {
if (strcmp(pname, "linux,phandle") == 0) {
np->node = *((u32 *)*p);
if (np->linux_phandle == 0)
np->linux_phandle = np->node;
}
if (strcmp(pname, "ibm,phandle") == 0)
np->linux_phandle = *((u32 *)*p);
pp->name = pname;
pp->length = sz;
pp->value = (void *)*p;
*prev_pp = pp;
prev_pp = &pp->next;
}
*p = _ALIGN((*p) + sz, 4);
}
/* with version 0x10 we may not have the name property, recreate
* it here from the unit name if absent
*/
if (!has_name) {
char *p1 = pathp, *ps = pathp, *pa = NULL;
int sz;
while (*p1) {
if ((*p1) == '@')
pa = p1;
if ((*p1) == '/')
ps = p1 + 1;
p1++;
}
if (pa < ps)
pa = p1;
sz = (pa - ps) + 1;
pp = unflatten_dt_alloc(&mem, sizeof(struct property) + sz,
__alignof__(struct property));
if (allnextpp) {
pp->name = "name";
pp->length = sz;
pp->value = pp + 1;
*prev_pp = pp;
prev_pp = &pp->next;
memcpy(pp->value, ps, sz - 1);
((char *)pp->value)[sz - 1] = 0;
pr_debug("fixed up name for %s -> %s\n", pathp,
(char *)pp->value);
}
}
if (allnextpp) {
*prev_pp = NULL;
np->name = of_get_property(np, "name", NULL);
np->type = of_get_property(np, "device_type", NULL);
if (!np->name)
np->name = "<NULL>";
if (!np->type)
np->type = "<NULL>";
}
while (tag == OF_DT_BEGIN_NODE) {
mem = unflatten_dt_node(mem, p, np, allnextpp, fpsize);
tag = *((u32 *)(*p));
}
if (tag != OF_DT_END_NODE) {
printk(KERN_INFO "Weird tag at end of node: %x\n", tag);
return mem;
}
*p += 4;
return mem;
}
/**
* unflattens the device-tree passed by the firmware, creating the
* tree of struct device_node. It also fills the "name" and "type"
* pointers of the nodes so the normal device-tree walking functions
* can be used (this used to be done by finish_device_tree)
*/
void __init unflatten_device_tree(void)
{
unsigned long start, mem, size;
struct device_node **allnextp = &allnodes;
pr_debug(" -> unflatten_device_tree()\n");
/* First pass, scan for size */
start = ((unsigned long)initial_boot_params) +
initial_boot_params->off_dt_struct;
size = unflatten_dt_node(0, &start, NULL, NULL, 0);
size = (size | 3) + 1;
pr_debug(" size is %lx, allocating...\n", size);
/* Allocate memory for the expanded device tree */
mem = lmb_alloc(size + 4, __alignof__(struct device_node));
mem = (unsigned long) __va(mem);
((u32 *)mem)[size / 4] = 0xdeadbeef;
pr_debug(" unflattening %lx...\n", mem);
/* Second pass, do actual unflattening */
start = ((unsigned long)initial_boot_params) +
initial_boot_params->off_dt_struct;
unflatten_dt_node(mem, &start, NULL, &allnextp, 0);
if (*((u32 *)start) != OF_DT_END)
printk(KERN_WARNING "Weird tag at end of tree: %08x\n",
*((u32 *)start));
if (((u32 *)mem)[size / 4] != 0xdeadbeef)
printk(KERN_WARNING "End of tree marker overwritten: %08x\n",
((u32 *)mem)[size / 4]);
*allnextp = NULL;
/* Get pointer to OF "/chosen" node for use everywhere */
of_chosen = of_find_node_by_path("/chosen");
if (of_chosen == NULL)
of_chosen = of_find_node_by_path("/chosen@0");
pr_debug(" <- unflatten_device_tree()\n");
}
#define early_init_dt_scan_drconf_memory(node) 0
static int __init early_init_dt_scan_cpus(unsigned long node,
const char *uname, int depth,
void *data)
{
static int logical_cpuid;
char *type = of_get_flat_dt_prop(node, "device_type", NULL);
const u32 *intserv;
int i, nthreads;
int found = 0;
/* We are scanning "cpu" nodes only */
if (type == NULL || strcmp(type, "cpu") != 0)
return 0;
/* Get physical cpuid */
intserv = of_get_flat_dt_prop(node, "reg", NULL);
nthreads = 1;
/*
* Now see if any of these threads match our boot cpu.
* NOTE: This must match the parsing done in smp_setup_cpu_maps.
*/
for (i = 0; i < nthreads; i++) {
/*
* version 2 of the kexec param format adds the phys cpuid of
* booted proc.
*/
if (initial_boot_params && initial_boot_params->version >= 2) {
if (intserv[i] ==
initial_boot_params->boot_cpuid_phys) {
found = 1;
break;
}
} else {
/*
* Check if it's the boot-cpu, set it's hw index now,
* unfortunately this format did not support booting
* off secondary threads.
*/
if (of_get_flat_dt_prop(node,
"linux,boot-cpu", NULL) != NULL) {
found = 1;
break;
}
}
#ifdef CONFIG_SMP
/* logical cpu id is always 0 on UP kernels */
logical_cpuid++;
#endif
}
if (found) {
pr_debug("boot cpu: logical %d physical %d\n", logical_cpuid,
intserv[i]);
boot_cpuid = logical_cpuid;
}
return 0;
}
#ifdef CONFIG_BLK_DEV_INITRD
static void __init early_init_dt_check_for_initrd(unsigned long node)
{
unsigned long l;
u32 *prop;
pr_debug("Looking for initrd properties... ");
prop = of_get_flat_dt_prop(node, "linux,initrd-start", &l);
if (prop) {
initrd_start = (unsigned long)
__va((u32)of_read_ulong(prop, l/4));
prop = of_get_flat_dt_prop(node, "linux,initrd-end", &l);
if (prop) {
initrd_end = (unsigned long)
__va((u32)of_read_ulong(prop, 1/4));
initrd_below_start_ok = 1;
} else {
initrd_start = 0;
}
}
pr_debug("initrd_start=0x%lx initrd_end=0x%lx\n",
initrd_start, initrd_end);
}
#else
static inline void early_init_dt_check_for_initrd(unsigned long node)
{
}
#endif /* CONFIG_BLK_DEV_INITRD */
static int __init early_init_dt_scan_chosen(unsigned long node,
const char *uname, int depth, void *data)
{
unsigned long l;
char *p;
pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
if (depth != 1 ||
(strcmp(uname, "chosen") != 0 &&
strcmp(uname, "chosen@0") != 0))
return 0;
#ifdef CONFIG_KEXEC
lprop = (u64 *)of_get_flat_dt_prop(node,
"linux,crashkernel-base", NULL);
if (lprop)
crashk_res.start = *lprop;
lprop = (u64 *)of_get_flat_dt_prop(node,
"linux,crashkernel-size", NULL);
if (lprop)
crashk_res.end = crashk_res.start + *lprop - 1;
#endif
early_init_dt_check_for_initrd(node);
/* Retreive command line */
p = of_get_flat_dt_prop(node, "bootargs", &l);
if (p != NULL && l > 0)
strlcpy(cmd_line, p, min((int)l, COMMAND_LINE_SIZE));
#ifdef CONFIG_CMDLINE
#ifndef CONFIG_CMDLINE_FORCE
if (p == NULL || l == 0 || (l == 1 && (*p) == 0))
#endif
strlcpy(cmd_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
#endif /* CONFIG_CMDLINE */
pr_debug("Command line is: %s\n", cmd_line);
/* break now */
return 1;
}
static int __init early_init_dt_scan_root(unsigned long node,
const char *uname, int depth, void *data)
{
u32 *prop;
if (depth != 0)
return 0;
prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
dt_root_size_cells = (prop == NULL) ? 1 : *prop;
pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells);
prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
dt_root_addr_cells = (prop == NULL) ? 2 : *prop;
pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
/* break now */
return 1;
}
static u64 __init dt_mem_next_cell(int s, cell_t **cellp)
{
cell_t *p = *cellp;
*cellp = p + s;
return of_read_number(p, s);
}
static int __init early_init_dt_scan_memory(unsigned long node,
const char *uname, int depth, void *data)
{
char *type = of_get_flat_dt_prop(node, "device_type", NULL);
cell_t *reg, *endp;
unsigned long l;
/* Look for the ibm,dynamic-reconfiguration-memory node */
/* if (depth == 1 &&
strcmp(uname, "ibm,dynamic-reconfiguration-memory") == 0)
return early_init_dt_scan_drconf_memory(node);
*/
/* We are scanning "memory" nodes only */
if (type == NULL) {
/*
* The longtrail doesn't have a device_type on the
* /memory node, so look for the node called /memory@0.
*/
if (depth != 1 || strcmp(uname, "memory@0") != 0)
return 0;
} else if (strcmp(type, "memory") != 0)
return 0;
reg = (cell_t *)of_get_flat_dt_prop(node, "linux,usable-memory", &l);
if (reg == NULL)
reg = (cell_t *)of_get_flat_dt_prop(node, "reg", &l);
if (reg == NULL)
return 0;
endp = reg + (l / sizeof(cell_t));
pr_debug("memory scan node %s, reg size %ld, data: %x %x %x %x,\n",
uname, l, reg[0], reg[1], reg[2], reg[3]);
while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
u64 base, size;
base = dt_mem_next_cell(dt_root_addr_cells, ®);
size = dt_mem_next_cell(dt_root_size_cells, ®);
if (size == 0)
continue;
pr_debug(" - %llx , %llx\n", (unsigned long long)base,
(unsigned long long)size);
lmb_add(base, size);
}
return 0;
}
#ifdef CONFIG_PHYP_DUMP
/**
* phyp_dump_calculate_reserve_size() - reserve variable boot area 5% or arg
*
* Function to find the largest size we need to reserve
* during early boot process.
*
* It either looks for boot param and returns that OR
* returns larger of 256 or 5% rounded down to multiples of 256MB.
*
*/
static inline unsigned long phyp_dump_calculate_reserve_size(void)
{
unsigned long tmp;
if (phyp_dump_info->reserve_bootvar)
return phyp_dump_info->reserve_bootvar;
/* divide by 20 to get 5% of value */
tmp = lmb_end_of_DRAM();
do_div(tmp, 20);
/* round it down in multiples of 256 */
tmp = tmp & ~0x0FFFFFFFUL;
return (tmp > PHYP_DUMP_RMR_END ? tmp : PHYP_DUMP_RMR_END);
}
/**
* phyp_dump_reserve_mem() - reserve all not-yet-dumped mmemory
*
* This routine may reserve memory regions in the kernel only
* if the system is supported and a dump was taken in last
* boot instance or if the hardware is supported and the
* scratch area needs to be setup. In other instances it returns
* without reserving anything. The memory in case of dump being
* active is freed when the dump is collected (by userland tools).
*/
static void __init phyp_dump_reserve_mem(void)
{
unsigned long base, size;
unsigned long variable_reserve_size;
if (!phyp_dump_info->phyp_dump_configured) {
printk(KERN_ERR "Phyp-dump not supported on this hardware\n");
return;
}
if (!phyp_dump_info->phyp_dump_at_boot) {
printk(KERN_INFO "Phyp-dump disabled at boot time\n");
return;
}
variable_reserve_size = phyp_dump_calculate_reserve_size();
if (phyp_dump_info->phyp_dump_is_active) {
/* Reserve *everything* above RMR.Area freed by userland tools*/
base = variable_reserve_size;
size = lmb_end_of_DRAM() - base;
/* XXX crashed_ram_end is wrong, since it may be beyond
* the memory_limit, it will need to be adjusted. */
lmb_reserve(base, size);
phyp_dump_info->init_reserve_start = base;
phyp_dump_info->init_reserve_size = size;
} else {
size = phyp_dump_info->cpu_state_size +
phyp_dump_info->hpte_region_size +
variable_reserve_size;
base = lmb_end_of_DRAM() - size;
lmb_reserve(base, size);
phyp_dump_info->init_reserve_start = base;
phyp_dump_info->init_reserve_size = size;
}
}
#else
static inline void __init phyp_dump_reserve_mem(void) {}
#endif /* CONFIG_PHYP_DUMP && CONFIG_PPC_RTAS */
#ifdef CONFIG_EARLY_PRINTK
/* MS this is Microblaze specifig function */
static int __init early_init_dt_scan_serial(unsigned long node,
const char *uname, int depth, void *data)
{
unsigned long l;
char *p;
int *addr;
pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
/* find all serial nodes */
if (strncmp(uname, "serial", 6) != 0)
return 0;
early_init_dt_check_for_initrd(node);
/* find compatible node with uartlite */
p = of_get_flat_dt_prop(node, "compatible", &l);
if ((strncmp(p, "xlnx,xps-uartlite", 17) != 0) &&
(strncmp(p, "xlnx,opb-uartlite", 17) != 0))
return 0;
addr = of_get_flat_dt_prop(node, "reg", &l);
return *addr; /* return address */
}
/* this function is looking for early uartlite console - Microblaze specific */
int __init early_uartlite_console(void)
{
return of_scan_flat_dt(early_init_dt_scan_serial, NULL);
}
#endif
void __init early_init_devtree(void *params)
{
pr_debug(" -> early_init_devtree(%p)\n", params);
/* Setup flat device-tree pointer */
initial_boot_params = params;
#ifdef CONFIG_PHYP_DUMP
/* scan tree to see if dump occured during last boot */
of_scan_flat_dt(early_init_dt_scan_phyp_dump, NULL);
#endif
/* Retrieve various informations from the /chosen node of the
* device-tree, including the platform type, initrd location and
* size, TCE reserve, and more ...
*/
of_scan_flat_dt(early_init_dt_scan_chosen, NULL);
/* Scan memory nodes and rebuild LMBs */
lmb_init();
of_scan_flat_dt(early_init_dt_scan_root, NULL);
of_scan_flat_dt(early_init_dt_scan_memory, NULL);
/* Save command line for /proc/cmdline and then parse parameters */
strlcpy(boot_command_line, cmd_line, COMMAND_LINE_SIZE);
parse_early_param();
lmb_analyze();
pr_debug("Phys. mem: %lx\n", (unsigned long) lmb_phys_mem_size());
pr_debug("Scanning CPUs ...\n");
/* Retreive CPU related informations from the flat tree
* (altivec support, boot CPU ID, ...)
*/
of_scan_flat_dt(early_init_dt_scan_cpus, NULL);
pr_debug(" <- early_init_devtree()\n");
}
/**
* Indicates whether the root node has a given value in its
* compatible property.
*/
int machine_is_compatible(const char *compat)
{
struct device_node *root;
int rc = 0;
root = of_find_node_by_path("/");
if (root) {
rc = of_device_is_compatible(root, compat);
of_node_put(root);
}
return rc;
}
EXPORT_SYMBOL(machine_is_compatible);
/*******
*
* New implementation of the OF "find" APIs, return a refcounted
* object, call of_node_put() when done. The device tree and list
* are protected by a rw_lock.
*
* Note that property management will need some locking as well,
* this isn't dealt with yet.
*
*******/
/**
* of_find_node_by_phandle - Find a node given a phandle
* @handle: phandle of the node to find
*
* Returns a node pointer with refcount incremented, use
* of_node_put() on it when done.
*/
struct device_node *of_find_node_by_phandle(phandle handle)
{
struct device_node *np;
read_lock(&devtree_lock);
for (np = allnodes; np != NULL; np = np->allnext)
if (np->linux_phandle == handle)
break;
of_node_get(np);
read_unlock(&devtree_lock);
return np;
}
EXPORT_SYMBOL(of_find_node_by_phandle);
/**
* of_find_all_nodes - Get next node in global list
* @prev: Previous node or NULL to start iteration
* of_node_put() will be called on it
*
* Returns a node pointer with refcount incremented, use
* of_node_put() on it when done.
*/
struct device_node *of_find_all_nodes(struct device_node *prev)
{
struct device_node *np;
read_lock(&devtree_lock);
np = prev ? prev->allnext : allnodes;
for (; np != NULL; np = np->allnext)
if (of_node_get(np))
break;
of_node_put(prev);
read_unlock(&devtree_lock);
return np;
}
EXPORT_SYMBOL(of_find_all_nodes);
/**
* of_node_get - Increment refcount of a node
* @node: Node to inc refcount, NULL is supported to
* simplify writing of callers
*
* Returns node.
*/
struct device_node *of_node_get(struct device_node *node)
{
if (node)
kref_get(&node->kref);
return node;
}
EXPORT_SYMBOL(of_node_get);
static inline struct device_node *kref_to_device_node(struct kref *kref)
{
return container_of(kref, struct device_node, kref);
}
/**
* of_node_release - release a dynamically allocated node
* @kref: kref element of the node to be released
*
* In of_node_put() this function is passed to kref_put()
* as the destructor.
*/
static void of_node_release(struct kref *kref)
{
struct device_node *node = kref_to_device_node(kref);
struct property *prop = node->properties;
/* We should never be releasing nodes that haven't been detached. */
if (!of_node_check_flag(node, OF_DETACHED)) {
printk(KERN_INFO "WARNING: Bad of_node_put() on %s\n",
node->full_name);
dump_stack();
kref_init(&node->kref);
return;
}
if (!of_node_check_flag(node, OF_DYNAMIC))
return;
while (prop) {
struct property *next = prop->next;
kfree(prop->name);
kfree(prop->value);
kfree(prop);
prop = next;
if (!prop) {
prop = node->deadprops;
node->deadprops = NULL;
}
}
kfree(node->full_name);
kfree(node->data);
kfree(node);
}
/**
* of_node_put - Decrement refcount of a node
* @node: Node to dec refcount, NULL is supported to
* simplify writing of callers
*
*/
void of_node_put(struct device_node *node)
{
if (node)
kref_put(&node->kref, of_node_release);
}
EXPORT_SYMBOL(of_node_put);
/*
* Plug a device node into the tree and global list.
*/
void of_attach_node(struct device_node *np)
{
unsigned long flags;
write_lock_irqsave(&devtree_lock, flags);
np->sibling = np->parent->child;
np->allnext = allnodes;
np->parent->child = np;
allnodes = np;
write_unlock_irqrestore(&devtree_lock, flags);
}
/*
* "Unplug" a node from the device tree. The caller must hold
* a reference to the node. The memory associated with the node
* is not freed until its refcount goes to zero.
*/
void of_detach_node(struct device_node *np)
{
struct device_node *parent;
unsigned long flags;
write_lock_irqsave(&devtree_lock, flags);
parent = np->parent;
if (!parent)
goto out_unlock;
if (allnodes == np)
allnodes = np->allnext;
else {
struct device_node *prev;
for (prev = allnodes;
prev->allnext != np;
prev = prev->allnext)
;
prev->allnext = np->allnext;
}
if (parent->child == np)
parent->child = np->sibling;
else {
struct device_node *prevsib;
for (prevsib = np->parent->child;
prevsib->sibling != np;
prevsib = prevsib->sibling)
;
prevsib->sibling = np->sibling;
}
of_node_set_flag(np, OF_DETACHED);
out_unlock:
write_unlock_irqrestore(&devtree_lock, flags);
}
/*
* Add a property to a node
*/
int prom_add_property(struct device_node *np, struct property *prop)
{
struct property **next;
unsigned long flags;
prop->next = NULL;
write_lock_irqsave(&devtree_lock, flags);
next = &np->properties;
while (*next) {
if (strcmp(prop->name, (*next)->name) == 0) {
/* duplicate ! don't insert it */
write_unlock_irqrestore(&devtree_lock, flags);
return -1;
}
next = &(*next)->next;
}
*next = prop;
write_unlock_irqrestore(&devtree_lock, flags);
#ifdef CONFIG_PROC_DEVICETREE
/* try to add to proc as well if it was initialized */
if (np->pde)
proc_device_tree_add_prop(np->pde, prop);
#endif /* CONFIG_PROC_DEVICETREE */
return 0;
}
/*
* Remove a property from a node. Note that we don't actually
* remove it, since we have given out who-knows-how-many pointers
* to the data using get-property. Instead we just move the property
* to the "dead properties" list, so it won't be found any more.
*/
int prom_remove_property(struct device_node *np, struct property *prop)
{
struct property **next;
unsigned long flags;
int found = 0;
write_lock_irqsave(&devtree_lock, flags);
next = &np->properties;
while (*next) {
if (*next == prop) {
/* found the node */
*next = prop->next;
prop->next = np->deadprops;
np->deadprops = prop;
found = 1;
break;
}
next = &(*next)->next;
}
write_unlock_irqrestore(&devtree_lock, flags);
if (!found)
return -ENODEV;
#ifdef CONFIG_PROC_DEVICETREE
/* try to remove the proc node as well */
if (np->pde)
proc_device_tree_remove_prop(np->pde, prop);
#endif /* CONFIG_PROC_DEVICETREE */
return 0;
}
/*
* Update a property in a node. Note that we don't actually
* remove it, since we have given out who-knows-how-many pointers
* to the data using get-property. Instead we just move the property
* to the "dead properties" list, and add the new property to the
* property list
*/
int prom_update_property(struct device_node *np,
struct property *newprop,
struct property *oldprop)
{
struct property **next;
unsigned long flags;
int found = 0;
write_lock_irqsave(&devtree_lock, flags);
next = &np->properties;
while (*next) {
if (*next == oldprop) {
/* found the node */
newprop->next = oldprop->next;
*next = newprop;
oldprop->next = np->deadprops;
np->deadprops = oldprop;
found = 1;
break;
}
next = &(*next)->next;
}
write_unlock_irqrestore(&devtree_lock, flags);
if (!found)
return -ENODEV;
#ifdef CONFIG_PROC_DEVICETREE
/* try to add to proc as well if it was initialized */
if (np->pde)
proc_device_tree_update_prop(np->pde, newprop, oldprop);
#endif /* CONFIG_PROC_DEVICETREE */
return 0;
}
#if defined(CONFIG_DEBUG_FS) && defined(DEBUG)
static struct debugfs_blob_wrapper flat_dt_blob;
static int __init export_flat_device_tree(void)
{
struct dentry *d;
flat_dt_blob.data = initial_boot_params;
flat_dt_blob.size = initial_boot_params->totalsize;
d = debugfs_create_blob("flat-device-tree", S_IFREG | S_IRUSR,
of_debugfs_root, &flat_dt_blob);
if (!d)
return 1;
return 0;
}
device_initcall(export_flat_device_tree);
#endif
