linux/arch/powerpc/kernel/prom.c
Hollis Blanchard 6ca4f7494b powerpc: Force memory size to be a multiple of PAGE_SIZE
Ensure that total memory size is page-aligned, because otherwise
mark_bootmem() gets upset.

This error case was triggered by using 64 KiB pages in the kernel
while arch/powerpc/boot/4xx.c arbitrarily reduced the amount of memory
by 4096 (to work around a chip bug that affects the last 256 bytes of
physical memory).

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-12-29 09:53:14 +11:00

1721 lines
42 KiB
C

/*
* 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.
*/
#undef DEBUG
#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/rtas.h>
#include <asm/page.h>
#include <asm/processor.h>
#include <asm/irq.h>
#include <asm/io.h>
#include <asm/kdump.h>
#include <asm/smp.h>
#include <asm/system.h>
#include <asm/mmu.h>
#include <asm/pgtable.h>
#include <asm/pci.h>
#include <asm/iommu.h>
#include <asm/btext.h>
#include <asm/sections.h>
#include <asm/machdep.h>
#include <asm/pSeries_reconfig.h>
#include <asm/pci-bridge.h>
#include <asm/phyp_dump.h>
#include <asm/kexec.h>
#include <mm/mmu_decl.h>
#ifdef DEBUG
#define DBG(fmt...) printk(KERN_ERR fmt)
#else
#define DBG(fmt...)
#endif
static int __initdata dt_root_addr_cells;
static int __initdata dt_root_size_cells;
#ifdef CONFIG_PPC64
int __initdata iommu_is_off;
int __initdata iommu_force_on;
unsigned long tce_alloc_start, tce_alloc_end;
#endif
typedef u32 cell_t;
#if 0
static struct boot_param_header *initial_boot_params __initdata;
#else
struct boot_param_header *initial_boot_params;
#endif
extern struct device_node *allnodes; /* temporary while merging */
extern rwlock_t devtree_lock; /* temporary while merging */
/* 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 *p = np->full_name;
/* rebuild full path for new format */
if (dad && dad->parent) {
strcpy(p, dad->full_name);
#ifdef DEBUG
if ((strlen(p) + l + 1) != allocl) {
DBG("%s: p: %d, l: %d, a: %d\n",
pathp, (int)strlen(p), l, allocl);
}
#endif
p += strlen(p);
}
*(p++) = '/';
memcpy(p, 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 == 0)
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("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 *p = pathp, *ps = pathp, *pa = NULL;
int sz;
while (*p) {
if ((*p) == '@')
pa = p;
if ((*p) == '/')
ps = p + 1;
p++;
}
if (pa < ps)
pa = p;
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;
DBG("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("Weird tag at end of node: %x\n", tag);
return mem;
}
*p += 4;
return mem;
}
static int __init early_parse_mem(char *p)
{
if (!p)
return 1;
memory_limit = PAGE_ALIGN(memparse(p, &p));
DBG("memory limit = 0x%lx\n", memory_limit);
return 0;
}
early_param("mem", early_parse_mem);
/**
* move_device_tree - move tree to an unused area, if needed.
*
* The device tree may be allocated beyond our memory limit, or inside the
* crash kernel region for kdump. If so, move it out of the way.
*/
static void __init move_device_tree(void)
{
unsigned long start, size;
void *p;
DBG("-> move_device_tree\n");
start = __pa(initial_boot_params);
size = initial_boot_params->totalsize;
if ((memory_limit && (start + size) > memory_limit) ||
overlaps_crashkernel(start, size)) {
p = __va(lmb_alloc_base(size, PAGE_SIZE, lmb.rmo_size));
memcpy(p, initial_boot_params, size);
initial_boot_params = (struct boot_param_header *)p;
DBG("Moved device tree to 0x%p\n", p);
}
DBG("<- move_device_tree\n");
}
/**
* 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;
DBG(" -> 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;
DBG(" 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;
DBG(" 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");
DBG(" <- unflatten_device_tree()\n");
}
/*
* ibm,pa-features is a per-cpu property that contains a string of
* attribute descriptors, each of which has a 2 byte header plus up
* to 254 bytes worth of processor attribute bits. First header
* byte specifies the number of bytes following the header.
* Second header byte is an "attribute-specifier" type, of which
* zero is the only currently-defined value.
* Implementation: Pass in the byte and bit offset for the feature
* that we are interested in. The function will return -1 if the
* pa-features property is missing, or a 1/0 to indicate if the feature
* is supported/not supported. Note that the bit numbers are
* big-endian to match the definition in PAPR.
*/
static struct ibm_pa_feature {
unsigned long cpu_features; /* CPU_FTR_xxx bit */
unsigned int cpu_user_ftrs; /* PPC_FEATURE_xxx bit */
unsigned char pabyte; /* byte number in ibm,pa-features */
unsigned char pabit; /* bit number (big-endian) */
unsigned char invert; /* if 1, pa bit set => clear feature */
} ibm_pa_features[] __initdata = {
{0, PPC_FEATURE_HAS_MMU, 0, 0, 0},
{0, PPC_FEATURE_HAS_FPU, 0, 1, 0},
{CPU_FTR_SLB, 0, 0, 2, 0},
{CPU_FTR_CTRL, 0, 0, 3, 0},
{CPU_FTR_NOEXECUTE, 0, 0, 6, 0},
{CPU_FTR_NODSISRALIGN, 0, 1, 1, 1},
{CPU_FTR_CI_LARGE_PAGE, 0, 1, 2, 0},
{CPU_FTR_REAL_LE, PPC_FEATURE_TRUE_LE, 5, 0, 0},
};
static void __init scan_features(unsigned long node, unsigned char *ftrs,
unsigned long tablelen,
struct ibm_pa_feature *fp,
unsigned long ft_size)
{
unsigned long i, len, bit;
/* find descriptor with type == 0 */
for (;;) {
if (tablelen < 3)
return;
len = 2 + ftrs[0];
if (tablelen < len)
return; /* descriptor 0 not found */
if (ftrs[1] == 0)
break;
tablelen -= len;
ftrs += len;
}
/* loop over bits we know about */
for (i = 0; i < ft_size; ++i, ++fp) {
if (fp->pabyte >= ftrs[0])
continue;
bit = (ftrs[2 + fp->pabyte] >> (7 - fp->pabit)) & 1;
if (bit ^ fp->invert) {
cur_cpu_spec->cpu_features |= fp->cpu_features;
cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftrs;
} else {
cur_cpu_spec->cpu_features &= ~fp->cpu_features;
cur_cpu_spec->cpu_user_features &= ~fp->cpu_user_ftrs;
}
}
}
static void __init check_cpu_pa_features(unsigned long node)
{
unsigned char *pa_ftrs;
unsigned long tablelen;
pa_ftrs = of_get_flat_dt_prop(node, "ibm,pa-features", &tablelen);
if (pa_ftrs == NULL)
return;
scan_features(node, pa_ftrs, tablelen,
ibm_pa_features, ARRAY_SIZE(ibm_pa_features));
}
#ifdef CONFIG_PPC64
static void __init check_cpu_slb_size(unsigned long node)
{
u32 *slb_size_ptr;
slb_size_ptr = of_get_flat_dt_prop(node, "ibm,slb-size", NULL);
if (slb_size_ptr != NULL) {
mmu_slb_size = *slb_size_ptr;
}
}
#else
#define check_cpu_slb_size(node) do { } while(0)
#endif
static struct feature_property {
const char *name;
u32 min_value;
unsigned long cpu_feature;
unsigned long cpu_user_ftr;
} feature_properties[] __initdata = {
#ifdef CONFIG_ALTIVEC
{"altivec", 0, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
{"ibm,vmx", 1, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
#endif /* CONFIG_ALTIVEC */
#ifdef CONFIG_VSX
/* Yes, this _really_ is ibm,vmx == 2 to enable VSX */
{"ibm,vmx", 2, CPU_FTR_VSX, PPC_FEATURE_HAS_VSX},
#endif /* CONFIG_VSX */
#ifdef CONFIG_PPC64
{"ibm,dfp", 1, 0, PPC_FEATURE_HAS_DFP},
{"ibm,purr", 1, CPU_FTR_PURR, 0},
{"ibm,spurr", 1, CPU_FTR_SPURR, 0},
#endif /* CONFIG_PPC64 */
};
#if defined(CONFIG_44x) && defined(CONFIG_PPC_FPU)
static inline void identical_pvr_fixup(unsigned long node)
{
unsigned int pvr;
char *model = of_get_flat_dt_prop(node, "model", NULL);
/*
* Since 440GR(x)/440EP(x) processors have the same pvr,
* we check the node path and set bit 28 in the cur_cpu_spec
* pvr for EP(x) processor version. This bit is always 0 in
* the "real" pvr. Then we call identify_cpu again with
* the new logical pvr to enable FPU support.
*/
if (model && strstr(model, "440EP")) {
pvr = cur_cpu_spec->pvr_value | 0x8;
identify_cpu(0, pvr);
DBG("Using logical pvr %x for %s\n", pvr, model);
}
}
#else
#define identical_pvr_fixup(node) do { } while(0)
#endif
static void __init check_cpu_feature_properties(unsigned long node)
{
unsigned long i;
struct feature_property *fp = feature_properties;
const u32 *prop;
for (i = 0; i < ARRAY_SIZE(feature_properties); ++i, ++fp) {
prop = of_get_flat_dt_prop(node, fp->name, NULL);
if (prop && *prop >= fp->min_value) {
cur_cpu_spec->cpu_features |= fp->cpu_feature;
cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftr;
}
}
}
static int __init early_init_dt_scan_cpus(unsigned long node,
const char *uname, int depth,
void *data)
{
static int logical_cpuid = 0;
char *type = of_get_flat_dt_prop(node, "device_type", NULL);
const u32 *prop;
const u32 *intserv;
int i, nthreads;
unsigned long len;
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, "ibm,ppc-interrupt-server#s", &len);
if (intserv) {
nthreads = len / sizeof(int);
} else {
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) {
DBG("boot cpu: logical %d physical %d\n", logical_cpuid,
intserv[i]);
boot_cpuid = logical_cpuid;
set_hard_smp_processor_id(boot_cpuid, intserv[i]);
/*
* PAPR defines "logical" PVR values for cpus that
* meet various levels of the architecture:
* 0x0f000001 Architecture version 2.04
* 0x0f000002 Architecture version 2.05
* If the cpu-version property in the cpu node contains
* such a value, we call identify_cpu again with the
* logical PVR value in order to use the cpu feature
* bits appropriate for the architecture level.
*
* A POWER6 partition in "POWER6 architected" mode
* uses the 0x0f000002 PVR value; in POWER5+ mode
* it uses 0x0f000001.
*/
prop = of_get_flat_dt_prop(node, "cpu-version", NULL);
if (prop && (*prop & 0xff000000) == 0x0f000000)
identify_cpu(0, *prop);
identical_pvr_fixup(node);
}
check_cpu_feature_properties(node);
check_cpu_pa_features(node);
check_cpu_slb_size(node);
#ifdef CONFIG_PPC_PSERIES
if (nthreads > 1)
cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
else
cur_cpu_spec->cpu_features &= ~CPU_FTR_SMT;
#endif
return 0;
}
#ifdef CONFIG_BLK_DEV_INITRD
static void __init early_init_dt_check_for_initrd(unsigned long node)
{
unsigned long l;
u32 *prop;
DBG("Looking for initrd properties... ");
prop = of_get_flat_dt_prop(node, "linux,initrd-start", &l);
if (prop) {
initrd_start = (unsigned long)__va(of_read_ulong(prop, l/4));
prop = of_get_flat_dt_prop(node, "linux,initrd-end", &l);
if (prop) {
initrd_end = (unsigned long)
__va(of_read_ulong(prop, l/4));
initrd_below_start_ok = 1;
} else {
initrd_start = 0;
}
}
DBG("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 *lprop;
unsigned long l;
char *p;
DBG("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_PPC64
/* check if iommu is forced on or off */
if (of_get_flat_dt_prop(node, "linux,iommu-off", NULL) != NULL)
iommu_is_off = 1;
if (of_get_flat_dt_prop(node, "linux,iommu-force-on", NULL) != NULL)
iommu_force_on = 1;
#endif
/* mem=x on the command line is the preferred mechanism */
lprop = of_get_flat_dt_prop(node, "linux,memory-limit", NULL);
if (lprop)
memory_limit = *lprop;
#ifdef CONFIG_PPC64
lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-start", NULL);
if (lprop)
tce_alloc_start = *lprop;
lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-end", NULL);
if (lprop)
tce_alloc_end = *lprop;
#endif
#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
if (p == NULL || l == 0 || (l == 1 && (*p) == 0))
strlcpy(cmd_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
#endif /* CONFIG_CMDLINE */
DBG("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;
DBG("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;
DBG("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);
}
#ifdef CONFIG_PPC_PSERIES
/*
* Interpret the ibm,dynamic-memory property in the
* /ibm,dynamic-reconfiguration-memory node.
* This contains a list of memory blocks along with NUMA affinity
* information.
*/
static int __init early_init_dt_scan_drconf_memory(unsigned long node)
{
cell_t *dm, *ls, *usm;
unsigned long l, n, flags;
u64 base, size, lmb_size;
unsigned int is_kexec_kdump = 0, rngs;
ls = (cell_t *)of_get_flat_dt_prop(node, "ibm,lmb-size", &l);
if (ls == NULL || l < dt_root_size_cells * sizeof(cell_t))
return 0;
lmb_size = dt_mem_next_cell(dt_root_size_cells, &ls);
dm = (cell_t *)of_get_flat_dt_prop(node, "ibm,dynamic-memory", &l);
if (dm == NULL || l < sizeof(cell_t))
return 0;
n = *dm++; /* number of entries */
if (l < (n * (dt_root_addr_cells + 4) + 1) * sizeof(cell_t))
return 0;
/* check if this is a kexec/kdump kernel. */
usm = (cell_t *)of_get_flat_dt_prop(node, "linux,drconf-usable-memory",
&l);
if (usm != NULL)
is_kexec_kdump = 1;
for (; n != 0; --n) {
base = dt_mem_next_cell(dt_root_addr_cells, &dm);
flags = dm[3];
/* skip DRC index, pad, assoc. list index, flags */
dm += 4;
/* skip this block if the reserved bit is set in flags (0x80)
or if the block is not assigned to this partition (0x8) */
if ((flags & 0x80) || !(flags & 0x8))
continue;
size = lmb_size;
rngs = 1;
if (is_kexec_kdump) {
/*
* For each lmb in ibm,dynamic-memory, a corresponding
* entry in linux,drconf-usable-memory property contains
* a counter 'p' followed by 'p' (base, size) duple.
* Now read the counter from
* linux,drconf-usable-memory property
*/
rngs = dt_mem_next_cell(dt_root_size_cells, &usm);
if (!rngs) /* there are no (base, size) duple */
continue;
}
do {
if (is_kexec_kdump) {
base = dt_mem_next_cell(dt_root_addr_cells,
&usm);
size = dt_mem_next_cell(dt_root_size_cells,
&usm);
}
if (iommu_is_off) {
if (base >= 0x80000000ul)
continue;
if ((base + size) > 0x80000000ul)
size = 0x80000000ul - base;
}
lmb_add(base, size);
} while (--rngs);
}
lmb_dump_all();
return 0;
}
#else
#define early_init_dt_scan_drconf_memory(node) 0
#endif /* CONFIG_PPC_PSERIES */
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));
DBG("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, &reg);
size = dt_mem_next_cell(dt_root_size_cells, &reg);
if (size == 0)
continue;
DBG(" - %llx , %llx\n", (unsigned long long)base,
(unsigned long long)size);
#ifdef CONFIG_PPC64
if (iommu_is_off) {
if (base >= 0x80000000ul)
continue;
if ((base + size) > 0x80000000ul)
size = 0x80000000ul - base;
}
#endif
lmb_add(base, size);
memstart_addr = min((u64)memstart_addr, base);
}
return 0;
}
static void __init early_reserve_mem(void)
{
u64 base, size;
u64 *reserve_map;
unsigned long self_base;
unsigned long self_size;
reserve_map = (u64 *)(((unsigned long)initial_boot_params) +
initial_boot_params->off_mem_rsvmap);
/* before we do anything, lets reserve the dt blob */
self_base = __pa((unsigned long)initial_boot_params);
self_size = initial_boot_params->totalsize;
lmb_reserve(self_base, self_size);
#ifdef CONFIG_BLK_DEV_INITRD
/* then reserve the initrd, if any */
if (initrd_start && (initrd_end > initrd_start))
lmb_reserve(__pa(initrd_start), initrd_end - initrd_start);
#endif /* CONFIG_BLK_DEV_INITRD */
#ifdef CONFIG_PPC32
/*
* Handle the case where we might be booting from an old kexec
* image that setup the mem_rsvmap as pairs of 32-bit values
*/
if (*reserve_map > 0xffffffffull) {
u32 base_32, size_32;
u32 *reserve_map_32 = (u32 *)reserve_map;
while (1) {
base_32 = *(reserve_map_32++);
size_32 = *(reserve_map_32++);
if (size_32 == 0)
break;
/* skip if the reservation is for the blob */
if (base_32 == self_base && size_32 == self_size)
continue;
DBG("reserving: %x -> %x\n", base_32, size_32);
lmb_reserve(base_32, size_32);
}
return;
}
#endif
while (1) {
base = *(reserve_map++);
size = *(reserve_map++);
if (size == 0)
break;
DBG("reserving: %llx -> %llx\n", base, size);
lmb_reserve(base, size);
}
#if 0
DBG("memory reserved, lmbs :\n");
lmb_dump_all();
#endif
}
#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 */
void __init early_init_devtree(void *params)
{
unsigned long limit;
DBG(" -> early_init_devtree(%p)\n", params);
/* Setup flat device-tree pointer */
initial_boot_params = params;
#ifdef CONFIG_PPC_RTAS
/* Some machines might need RTAS info for debugging, grab it now. */
of_scan_flat_dt(early_init_dt_scan_rtas, NULL);
#endif
#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();
/* Reserve LMB regions used by kernel, initrd, dt, etc... */
lmb_reserve(PHYSICAL_START, __pa(klimit) - PHYSICAL_START);
/* If relocatable, reserve first 32k for interrupt vectors etc. */
if (PHYSICAL_START > MEMORY_START)
lmb_reserve(MEMORY_START, 0x8000);
reserve_kdump_trampoline();
reserve_crashkernel();
early_reserve_mem();
phyp_dump_reserve_mem();
limit = memory_limit;
if (! limit) {
unsigned long memsize;
/* Ensure that total memory size is page-aligned, because
* otherwise mark_bootmem() gets upset. */
lmb_analyze();
memsize = lmb_phys_mem_size();
if ((memsize & PAGE_MASK) != memsize)
limit = memsize & PAGE_MASK;
}
lmb_enforce_memory_limit(limit);
lmb_analyze();
DBG("Phys. mem: %lx\n", lmb_phys_mem_size());
/* We may need to relocate the flat tree, do it now.
* FIXME .. and the initrd too? */
move_device_tree();
DBG("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);
DBG(" <- 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 != 0; 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_next_cache_node - Find a node's subsidiary cache
* @np: node of type "cpu" or "cache"
*
* Returns a node pointer with refcount incremented, use
* of_node_put() on it when done. Caller should hold a reference
* to np.
*/
struct device_node *of_find_next_cache_node(struct device_node *np)
{
struct device_node *child;
const phandle *handle;
handle = of_get_property(np, "l2-cache", NULL);
if (!handle)
handle = of_get_property(np, "next-level-cache", NULL);
if (handle)
return of_find_node_by_phandle(*handle);
/* OF on pmac has nodes instead of properties named "l2-cache"
* beneath CPU nodes.
*/
if (!strcmp(np->type, "cpu"))
for_each_child_of_node(np, child)
if (!strcmp(child->type, "cache"))
return child;
return NULL;
}
/**
* 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 != 0; 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("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);
}
#ifdef CONFIG_PPC_PSERIES
/*
* Fix up the uninitialized fields in a new device node:
* name, type and pci-specific fields
*/
static int of_finish_dynamic_node(struct device_node *node)
{
struct device_node *parent = of_get_parent(node);
int err = 0;
const phandle *ibm_phandle;
node->name = of_get_property(node, "name", NULL);
node->type = of_get_property(node, "device_type", NULL);
if (!node->name)
node->name = "<NULL>";
if (!node->type)
node->type = "<NULL>";
if (!parent) {
err = -ENODEV;
goto out;
}
/* We don't support that function on PowerMac, at least
* not yet
*/
if (machine_is(powermac))
return -ENODEV;
/* fix up new node's linux_phandle field */
if ((ibm_phandle = of_get_property(node, "ibm,phandle", NULL)))
node->linux_phandle = *ibm_phandle;
out:
of_node_put(parent);
return err;
}
static int prom_reconfig_notifier(struct notifier_block *nb,
unsigned long action, void *node)
{
int err;
switch (action) {
case PSERIES_RECONFIG_ADD:
err = of_finish_dynamic_node(node);
if (err < 0) {
printk(KERN_ERR "finish_node returned %d\n", err);
err = NOTIFY_BAD;
}
break;
default:
err = NOTIFY_DONE;
break;
}
return err;
}
static struct notifier_block prom_reconfig_nb = {
.notifier_call = prom_reconfig_notifier,
.priority = 10, /* This one needs to run first */
};
static int __init prom_reconfig_setup(void)
{
return pSeries_reconfig_notifier_register(&prom_reconfig_nb);
}
__initcall(prom_reconfig_setup);
#endif
/*
* 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;
}
/* Find the device node for a given logical cpu number, also returns the cpu
* local thread number (index in ibm,interrupt-server#s) if relevant and
* asked for (non NULL)
*/
struct device_node *of_get_cpu_node(int cpu, unsigned int *thread)
{
int hardid;
struct device_node *np;
hardid = get_hard_smp_processor_id(cpu);
for_each_node_by_type(np, "cpu") {
const u32 *intserv;
unsigned int plen, t;
/* Check for ibm,ppc-interrupt-server#s. If it doesn't exist
* fallback to "reg" property and assume no threads
*/
intserv = of_get_property(np, "ibm,ppc-interrupt-server#s",
&plen);
if (intserv == NULL) {
const u32 *reg = of_get_property(np, "reg", NULL);
if (reg == NULL)
continue;
if (*reg == hardid) {
if (thread)
*thread = 0;
return np;
}
} else {
plen /= sizeof(u32);
for (t = 0; t < plen; t++) {
if (hardid == intserv[t]) {
if (thread)
*thread = t;
return np;
}
}
}
}
return NULL;
}
EXPORT_SYMBOL(of_get_cpu_node);
#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,
powerpc_debugfs_root, &flat_dt_blob);
if (!d)
return 1;
return 0;
}
__initcall(export_flat_device_tree);
#endif