/*
* 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>
/* export that to outside world */
struct device_node *of_chosen;
#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;
}
void __init early_init_dt_scan_chosen_arch(unsigned long node)
{
/* No Microblaze specific code here */
}
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);
__be32 *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 = (__be32 *)of_get_flat_dt_prop(node, "linux,usable-memory", &l);
if (reg == NULL)
reg = (__be32 *)of_get_flat_dt_prop(node, "reg", &l);
if (reg == NULL)
return 0;
endp = reg + (l / sizeof(__be32));
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");
}
/*******
*
* 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_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);
}
#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
