linux/arch/sparc64/kernel/prom.c
David S. Miller 9001f2850f [SPARC64]: Fix Tomatillo/Schizo IRQ handling.
The code in schizo_irq_trans_init() should set irq_data->sync_reg
to the location of the SYNC register if this is Tomatillo, and set
it to zero otherwise.  But that is not what it is doing.

As a result, non-Tomatillo systems were trying to access a
non-existent register resulting in bus errors at the first
PCI interrupt.

Thanks to Roland Stigge for the bug report.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-10-30 19:33:33 -08:00

1590 lines
38 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
*
* Adapted for sparc64 by David S. Miller davem@davemloft.net
*
* 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 <linux/kernel.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/bootmem.h>
#include <linux/module.h>
#include <asm/prom.h>
#include <asm/of_device.h>
#include <asm/oplib.h>
#include <asm/irq.h>
#include <asm/asi.h>
#include <asm/upa.h>
static struct device_node *allnodes;
/* use when traversing tree through the allnext, child, sibling,
* or parent members of struct device_node.
*/
static DEFINE_RWLOCK(devtree_lock);
int of_device_is_compatible(struct device_node *device, const char *compat)
{
const char* cp;
int cplen, l;
cp = (char *) of_get_property(device, "compatible", &cplen);
if (cp == NULL)
return 0;
while (cplen > 0) {
if (strncmp(cp, compat, strlen(compat)) == 0)
return 1;
l = strlen(cp) + 1;
cp += l;
cplen -= l;
}
return 0;
}
EXPORT_SYMBOL(of_device_is_compatible);
struct device_node *of_get_parent(const struct device_node *node)
{
struct device_node *np;
if (!node)
return NULL;
np = node->parent;
return np;
}
EXPORT_SYMBOL(of_get_parent);
struct device_node *of_get_next_child(const struct device_node *node,
struct device_node *prev)
{
struct device_node *next;
next = prev ? prev->sibling : node->child;
for (; next != 0; next = next->sibling) {
break;
}
return next;
}
EXPORT_SYMBOL(of_get_next_child);
struct device_node *of_find_node_by_path(const char *path)
{
struct device_node *np = allnodes;
for (; np != 0; np = np->allnext) {
if (np->full_name != 0 && strcmp(np->full_name, path) == 0)
break;
}
return np;
}
EXPORT_SYMBOL(of_find_node_by_path);
struct device_node *of_find_node_by_phandle(phandle handle)
{
struct device_node *np;
for (np = allnodes; np != 0; np = np->allnext)
if (np->node == handle)
break;
return np;
}
EXPORT_SYMBOL(of_find_node_by_phandle);
struct device_node *of_find_node_by_name(struct device_node *from,
const char *name)
{
struct device_node *np;
np = from ? from->allnext : allnodes;
for (; np != NULL; np = np->allnext)
if (np->name != NULL && strcmp(np->name, name) == 0)
break;
return np;
}
EXPORT_SYMBOL(of_find_node_by_name);
struct device_node *of_find_node_by_type(struct device_node *from,
const char *type)
{
struct device_node *np;
np = from ? from->allnext : allnodes;
for (; np != 0; np = np->allnext)
if (np->type != 0 && strcmp(np->type, type) == 0)
break;
return np;
}
EXPORT_SYMBOL(of_find_node_by_type);
struct device_node *of_find_compatible_node(struct device_node *from,
const char *type, const char *compatible)
{
struct device_node *np;
np = from ? from->allnext : allnodes;
for (; np != 0; np = np->allnext) {
if (type != NULL
&& !(np->type != 0 && strcmp(np->type, type) == 0))
continue;
if (of_device_is_compatible(np, compatible))
break;
}
return np;
}
EXPORT_SYMBOL(of_find_compatible_node);
struct property *of_find_property(struct device_node *np, const char *name,
int *lenp)
{
struct property *pp;
for (pp = np->properties; pp != 0; pp = pp->next) {
if (strcmp(pp->name, name) == 0) {
if (lenp != 0)
*lenp = pp->length;
break;
}
}
return pp;
}
EXPORT_SYMBOL(of_find_property);
/*
* Find a property with a given name for a given node
* and return the value.
*/
void *of_get_property(struct device_node *np, const char *name, int *lenp)
{
struct property *pp = of_find_property(np,name,lenp);
return pp ? pp->value : NULL;
}
EXPORT_SYMBOL(of_get_property);
int of_getintprop_default(struct device_node *np, const char *name, int def)
{
struct property *prop;
int len;
prop = of_find_property(np, name, &len);
if (!prop || len != 4)
return def;
return *(int *) prop->value;
}
EXPORT_SYMBOL(of_getintprop_default);
int of_n_addr_cells(struct device_node *np)
{
int* ip;
do {
if (np->parent)
np = np->parent;
ip = of_get_property(np, "#address-cells", NULL);
if (ip != NULL)
return *ip;
} while (np->parent);
/* No #address-cells property for the root node, default to 2 */
return 2;
}
EXPORT_SYMBOL(of_n_addr_cells);
int of_n_size_cells(struct device_node *np)
{
int* ip;
do {
if (np->parent)
np = np->parent;
ip = of_get_property(np, "#size-cells", NULL);
if (ip != NULL)
return *ip;
} while (np->parent);
/* No #size-cells property for the root node, default to 1 */
return 1;
}
EXPORT_SYMBOL(of_n_size_cells);
int of_set_property(struct device_node *dp, const char *name, void *val, int len)
{
struct property **prevp;
void *new_val;
int err;
new_val = kmalloc(len, GFP_KERNEL);
if (!new_val)
return -ENOMEM;
memcpy(new_val, val, len);
err = -ENODEV;
write_lock(&devtree_lock);
prevp = &dp->properties;
while (*prevp) {
struct property *prop = *prevp;
if (!strcmp(prop->name, name)) {
void *old_val = prop->value;
int ret;
ret = prom_setprop(dp->node, name, val, len);
err = -EINVAL;
if (ret >= 0) {
prop->value = new_val;
prop->length = len;
if (OF_IS_DYNAMIC(prop))
kfree(old_val);
OF_MARK_DYNAMIC(prop);
err = 0;
}
break;
}
prevp = &(*prevp)->next;
}
write_unlock(&devtree_lock);
/* XXX Upate procfs if necessary... */
return err;
}
EXPORT_SYMBOL(of_set_property);
static unsigned int prom_early_allocated;
static void * __init prom_early_alloc(unsigned long size)
{
void *ret;
ret = __alloc_bootmem(size, SMP_CACHE_BYTES, 0UL);
if (ret != NULL)
memset(ret, 0, size);
prom_early_allocated += size;
return ret;
}
#ifdef CONFIG_PCI
/* PSYCHO interrupt mapping support. */
#define PSYCHO_IMAP_A_SLOT0 0x0c00UL
#define PSYCHO_IMAP_B_SLOT0 0x0c20UL
static unsigned long psycho_pcislot_imap_offset(unsigned long ino)
{
unsigned int bus = (ino & 0x10) >> 4;
unsigned int slot = (ino & 0x0c) >> 2;
if (bus == 0)
return PSYCHO_IMAP_A_SLOT0 + (slot * 8);
else
return PSYCHO_IMAP_B_SLOT0 + (slot * 8);
}
#define PSYCHO_IMAP_SCSI 0x1000UL
#define PSYCHO_IMAP_ETH 0x1008UL
#define PSYCHO_IMAP_BPP 0x1010UL
#define PSYCHO_IMAP_AU_REC 0x1018UL
#define PSYCHO_IMAP_AU_PLAY 0x1020UL
#define PSYCHO_IMAP_PFAIL 0x1028UL
#define PSYCHO_IMAP_KMS 0x1030UL
#define PSYCHO_IMAP_FLPY 0x1038UL
#define PSYCHO_IMAP_SHW 0x1040UL
#define PSYCHO_IMAP_KBD 0x1048UL
#define PSYCHO_IMAP_MS 0x1050UL
#define PSYCHO_IMAP_SER 0x1058UL
#define PSYCHO_IMAP_TIM0 0x1060UL
#define PSYCHO_IMAP_TIM1 0x1068UL
#define PSYCHO_IMAP_UE 0x1070UL
#define PSYCHO_IMAP_CE 0x1078UL
#define PSYCHO_IMAP_A_ERR 0x1080UL
#define PSYCHO_IMAP_B_ERR 0x1088UL
#define PSYCHO_IMAP_PMGMT 0x1090UL
#define PSYCHO_IMAP_GFX 0x1098UL
#define PSYCHO_IMAP_EUPA 0x10a0UL
static unsigned long __psycho_onboard_imap_off[] = {
/*0x20*/ PSYCHO_IMAP_SCSI,
/*0x21*/ PSYCHO_IMAP_ETH,
/*0x22*/ PSYCHO_IMAP_BPP,
/*0x23*/ PSYCHO_IMAP_AU_REC,
/*0x24*/ PSYCHO_IMAP_AU_PLAY,
/*0x25*/ PSYCHO_IMAP_PFAIL,
/*0x26*/ PSYCHO_IMAP_KMS,
/*0x27*/ PSYCHO_IMAP_FLPY,
/*0x28*/ PSYCHO_IMAP_SHW,
/*0x29*/ PSYCHO_IMAP_KBD,
/*0x2a*/ PSYCHO_IMAP_MS,
/*0x2b*/ PSYCHO_IMAP_SER,
/*0x2c*/ PSYCHO_IMAP_TIM0,
/*0x2d*/ PSYCHO_IMAP_TIM1,
/*0x2e*/ PSYCHO_IMAP_UE,
/*0x2f*/ PSYCHO_IMAP_CE,
/*0x30*/ PSYCHO_IMAP_A_ERR,
/*0x31*/ PSYCHO_IMAP_B_ERR,
/*0x32*/ PSYCHO_IMAP_PMGMT,
/*0x33*/ PSYCHO_IMAP_GFX,
/*0x34*/ PSYCHO_IMAP_EUPA,
};
#define PSYCHO_ONBOARD_IRQ_BASE 0x20
#define PSYCHO_ONBOARD_IRQ_LAST 0x34
#define psycho_onboard_imap_offset(__ino) \
__psycho_onboard_imap_off[(__ino) - PSYCHO_ONBOARD_IRQ_BASE]
#define PSYCHO_ICLR_A_SLOT0 0x1400UL
#define PSYCHO_ICLR_SCSI 0x1800UL
#define psycho_iclr_offset(ino) \
((ino & 0x20) ? (PSYCHO_ICLR_SCSI + (((ino) & 0x1f) << 3)) : \
(PSYCHO_ICLR_A_SLOT0 + (((ino) & 0x1f)<<3)))
static unsigned int psycho_irq_build(struct device_node *dp,
unsigned int ino,
void *_data)
{
unsigned long controller_regs = (unsigned long) _data;
unsigned long imap, iclr;
unsigned long imap_off, iclr_off;
int inofixup = 0;
ino &= 0x3f;
if (ino < PSYCHO_ONBOARD_IRQ_BASE) {
/* PCI slot */
imap_off = psycho_pcislot_imap_offset(ino);
} else {
/* Onboard device */
if (ino > PSYCHO_ONBOARD_IRQ_LAST) {
prom_printf("psycho_irq_build: Wacky INO [%x]\n", ino);
prom_halt();
}
imap_off = psycho_onboard_imap_offset(ino);
}
/* Now build the IRQ bucket. */
imap = controller_regs + imap_off;
imap += 4;
iclr_off = psycho_iclr_offset(ino);
iclr = controller_regs + iclr_off;
iclr += 4;
if ((ino & 0x20) == 0)
inofixup = ino & 0x03;
return build_irq(inofixup, iclr, imap);
}
static void psycho_irq_trans_init(struct device_node *dp)
{
struct linux_prom64_registers *regs;
dp->irq_trans = prom_early_alloc(sizeof(struct of_irq_controller));
dp->irq_trans->irq_build = psycho_irq_build;
regs = of_get_property(dp, "reg", NULL);
dp->irq_trans->data = (void *) regs[2].phys_addr;
}
#define sabre_read(__reg) \
({ u64 __ret; \
__asm__ __volatile__("ldxa [%1] %2, %0" \
: "=r" (__ret) \
: "r" (__reg), "i" (ASI_PHYS_BYPASS_EC_E) \
: "memory"); \
__ret; \
})
struct sabre_irq_data {
unsigned long controller_regs;
unsigned int pci_first_busno;
};
#define SABRE_CONFIGSPACE 0x001000000UL
#define SABRE_WRSYNC 0x1c20UL
#define SABRE_CONFIG_BASE(CONFIG_SPACE) \
(CONFIG_SPACE | (1UL << 24))
#define SABRE_CONFIG_ENCODE(BUS, DEVFN, REG) \
(((unsigned long)(BUS) << 16) | \
((unsigned long)(DEVFN) << 8) | \
((unsigned long)(REG)))
/* When a device lives behind a bridge deeper in the PCI bus topology
* than APB, a special sequence must run to make sure all pending DMA
* transfers at the time of IRQ delivery are visible in the coherency
* domain by the cpu. This sequence is to perform a read on the far
* side of the non-APB bridge, then perform a read of Sabre's DMA
* write-sync register.
*/
static void sabre_wsync_handler(unsigned int ino, void *_arg1, void *_arg2)
{
unsigned int phys_hi = (unsigned int) (unsigned long) _arg1;
struct sabre_irq_data *irq_data = _arg2;
unsigned long controller_regs = irq_data->controller_regs;
unsigned long sync_reg = controller_regs + SABRE_WRSYNC;
unsigned long config_space = controller_regs + SABRE_CONFIGSPACE;
unsigned int bus, devfn;
u16 _unused;
config_space = SABRE_CONFIG_BASE(config_space);
bus = (phys_hi >> 16) & 0xff;
devfn = (phys_hi >> 8) & 0xff;
config_space |= SABRE_CONFIG_ENCODE(bus, devfn, 0x00);
__asm__ __volatile__("membar #Sync\n\t"
"lduha [%1] %2, %0\n\t"
"membar #Sync"
: "=r" (_unused)
: "r" ((u16 *) config_space),
"i" (ASI_PHYS_BYPASS_EC_E_L)
: "memory");
sabre_read(sync_reg);
}
#define SABRE_IMAP_A_SLOT0 0x0c00UL
#define SABRE_IMAP_B_SLOT0 0x0c20UL
#define SABRE_IMAP_SCSI 0x1000UL
#define SABRE_IMAP_ETH 0x1008UL
#define SABRE_IMAP_BPP 0x1010UL
#define SABRE_IMAP_AU_REC 0x1018UL
#define SABRE_IMAP_AU_PLAY 0x1020UL
#define SABRE_IMAP_PFAIL 0x1028UL
#define SABRE_IMAP_KMS 0x1030UL
#define SABRE_IMAP_FLPY 0x1038UL
#define SABRE_IMAP_SHW 0x1040UL
#define SABRE_IMAP_KBD 0x1048UL
#define SABRE_IMAP_MS 0x1050UL
#define SABRE_IMAP_SER 0x1058UL
#define SABRE_IMAP_UE 0x1070UL
#define SABRE_IMAP_CE 0x1078UL
#define SABRE_IMAP_PCIERR 0x1080UL
#define SABRE_IMAP_GFX 0x1098UL
#define SABRE_IMAP_EUPA 0x10a0UL
#define SABRE_ICLR_A_SLOT0 0x1400UL
#define SABRE_ICLR_B_SLOT0 0x1480UL
#define SABRE_ICLR_SCSI 0x1800UL
#define SABRE_ICLR_ETH 0x1808UL
#define SABRE_ICLR_BPP 0x1810UL
#define SABRE_ICLR_AU_REC 0x1818UL
#define SABRE_ICLR_AU_PLAY 0x1820UL
#define SABRE_ICLR_PFAIL 0x1828UL
#define SABRE_ICLR_KMS 0x1830UL
#define SABRE_ICLR_FLPY 0x1838UL
#define SABRE_ICLR_SHW 0x1840UL
#define SABRE_ICLR_KBD 0x1848UL
#define SABRE_ICLR_MS 0x1850UL
#define SABRE_ICLR_SER 0x1858UL
#define SABRE_ICLR_UE 0x1870UL
#define SABRE_ICLR_CE 0x1878UL
#define SABRE_ICLR_PCIERR 0x1880UL
static unsigned long sabre_pcislot_imap_offset(unsigned long ino)
{
unsigned int bus = (ino & 0x10) >> 4;
unsigned int slot = (ino & 0x0c) >> 2;
if (bus == 0)
return SABRE_IMAP_A_SLOT0 + (slot * 8);
else
return SABRE_IMAP_B_SLOT0 + (slot * 8);
}
static unsigned long __sabre_onboard_imap_off[] = {
/*0x20*/ SABRE_IMAP_SCSI,
/*0x21*/ SABRE_IMAP_ETH,
/*0x22*/ SABRE_IMAP_BPP,
/*0x23*/ SABRE_IMAP_AU_REC,
/*0x24*/ SABRE_IMAP_AU_PLAY,
/*0x25*/ SABRE_IMAP_PFAIL,
/*0x26*/ SABRE_IMAP_KMS,
/*0x27*/ SABRE_IMAP_FLPY,
/*0x28*/ SABRE_IMAP_SHW,
/*0x29*/ SABRE_IMAP_KBD,
/*0x2a*/ SABRE_IMAP_MS,
/*0x2b*/ SABRE_IMAP_SER,
/*0x2c*/ 0 /* reserved */,
/*0x2d*/ 0 /* reserved */,
/*0x2e*/ SABRE_IMAP_UE,
/*0x2f*/ SABRE_IMAP_CE,
/*0x30*/ SABRE_IMAP_PCIERR,
/*0x31*/ 0 /* reserved */,
/*0x32*/ 0 /* reserved */,
/*0x33*/ SABRE_IMAP_GFX,
/*0x34*/ SABRE_IMAP_EUPA,
};
#define SABRE_ONBOARD_IRQ_BASE 0x20
#define SABRE_ONBOARD_IRQ_LAST 0x30
#define sabre_onboard_imap_offset(__ino) \
__sabre_onboard_imap_off[(__ino) - SABRE_ONBOARD_IRQ_BASE]
#define sabre_iclr_offset(ino) \
((ino & 0x20) ? (SABRE_ICLR_SCSI + (((ino) & 0x1f) << 3)) : \
(SABRE_ICLR_A_SLOT0 + (((ino) & 0x1f)<<3)))
static int sabre_device_needs_wsync(struct device_node *dp)
{
struct device_node *parent = dp->parent;
char *parent_model, *parent_compat;
/* This traversal up towards the root is meant to
* handle two cases:
*
* 1) non-PCI bus sitting under PCI, such as 'ebus'
* 2) the PCI controller interrupts themselves, which
* will use the sabre_irq_build but do not need
* the DMA synchronization handling
*/
while (parent) {
if (!strcmp(parent->type, "pci"))
break;
parent = parent->parent;
}
if (!parent)
return 0;
parent_model = of_get_property(parent,
"model", NULL);
if (parent_model &&
(!strcmp(parent_model, "SUNW,sabre") ||
!strcmp(parent_model, "SUNW,simba")))
return 0;
parent_compat = of_get_property(parent,
"compatible", NULL);
if (parent_compat &&
(!strcmp(parent_compat, "pci108e,a000") ||
!strcmp(parent_compat, "pci108e,a001")))
return 0;
return 1;
}
static unsigned int sabre_irq_build(struct device_node *dp,
unsigned int ino,
void *_data)
{
struct sabre_irq_data *irq_data = _data;
unsigned long controller_regs = irq_data->controller_regs;
struct linux_prom_pci_registers *regs;
unsigned long imap, iclr;
unsigned long imap_off, iclr_off;
int inofixup = 0;
int virt_irq;
ino &= 0x3f;
if (ino < SABRE_ONBOARD_IRQ_BASE) {
/* PCI slot */
imap_off = sabre_pcislot_imap_offset(ino);
} else {
/* onboard device */
if (ino > SABRE_ONBOARD_IRQ_LAST) {
prom_printf("sabre_irq_build: Wacky INO [%x]\n", ino);
prom_halt();
}
imap_off = sabre_onboard_imap_offset(ino);
}
/* Now build the IRQ bucket. */
imap = controller_regs + imap_off;
imap += 4;
iclr_off = sabre_iclr_offset(ino);
iclr = controller_regs + iclr_off;
iclr += 4;
if ((ino & 0x20) == 0)
inofixup = ino & 0x03;
virt_irq = build_irq(inofixup, iclr, imap);
/* If the parent device is a PCI<->PCI bridge other than
* APB, we have to install a pre-handler to ensure that
* all pending DMA is drained before the interrupt handler
* is run.
*/
regs = of_get_property(dp, "reg", NULL);
if (regs && sabre_device_needs_wsync(dp)) {
irq_install_pre_handler(virt_irq,
sabre_wsync_handler,
(void *) (long) regs->phys_hi,
(void *) irq_data);
}
return virt_irq;
}
static void sabre_irq_trans_init(struct device_node *dp)
{
struct linux_prom64_registers *regs;
struct sabre_irq_data *irq_data;
u32 *busrange;
dp->irq_trans = prom_early_alloc(sizeof(struct of_irq_controller));
dp->irq_trans->irq_build = sabre_irq_build;
irq_data = prom_early_alloc(sizeof(struct sabre_irq_data));
regs = of_get_property(dp, "reg", NULL);
irq_data->controller_regs = regs[0].phys_addr;
busrange = of_get_property(dp, "bus-range", NULL);
irq_data->pci_first_busno = busrange[0];
dp->irq_trans->data = irq_data;
}
/* SCHIZO interrupt mapping support. Unlike Psycho, for this controller the
* imap/iclr registers are per-PBM.
*/
#define SCHIZO_IMAP_BASE 0x1000UL
#define SCHIZO_ICLR_BASE 0x1400UL
static unsigned long schizo_imap_offset(unsigned long ino)
{
return SCHIZO_IMAP_BASE + (ino * 8UL);
}
static unsigned long schizo_iclr_offset(unsigned long ino)
{
return SCHIZO_ICLR_BASE + (ino * 8UL);
}
static unsigned long schizo_ino_to_iclr(unsigned long pbm_regs,
unsigned int ino)
{
return pbm_regs + schizo_iclr_offset(ino) + 4;
}
static unsigned long schizo_ino_to_imap(unsigned long pbm_regs,
unsigned int ino)
{
return pbm_regs + schizo_imap_offset(ino) + 4;
}
#define schizo_read(__reg) \
({ u64 __ret; \
__asm__ __volatile__("ldxa [%1] %2, %0" \
: "=r" (__ret) \
: "r" (__reg), "i" (ASI_PHYS_BYPASS_EC_E) \
: "memory"); \
__ret; \
})
#define schizo_write(__reg, __val) \
__asm__ __volatile__("stxa %0, [%1] %2" \
: /* no outputs */ \
: "r" (__val), "r" (__reg), \
"i" (ASI_PHYS_BYPASS_EC_E) \
: "memory")
static void tomatillo_wsync_handler(unsigned int ino, void *_arg1, void *_arg2)
{
unsigned long sync_reg = (unsigned long) _arg2;
u64 mask = 1UL << (ino & IMAP_INO);
u64 val;
int limit;
schizo_write(sync_reg, mask);
limit = 100000;
val = 0;
while (--limit) {
val = schizo_read(sync_reg);
if (!(val & mask))
break;
}
if (limit <= 0) {
printk("tomatillo_wsync_handler: DMA won't sync [%lx:%lx]\n",
val, mask);
}
if (_arg1) {
static unsigned char cacheline[64]
__attribute__ ((aligned (64)));
__asm__ __volatile__("rd %%fprs, %0\n\t"
"or %0, %4, %1\n\t"
"wr %1, 0x0, %%fprs\n\t"
"stda %%f0, [%5] %6\n\t"
"wr %0, 0x0, %%fprs\n\t"
"membar #Sync"
: "=&r" (mask), "=&r" (val)
: "0" (mask), "1" (val),
"i" (FPRS_FEF), "r" (&cacheline[0]),
"i" (ASI_BLK_COMMIT_P));
}
}
struct schizo_irq_data {
unsigned long pbm_regs;
unsigned long sync_reg;
u32 portid;
int chip_version;
};
static unsigned int schizo_irq_build(struct device_node *dp,
unsigned int ino,
void *_data)
{
struct schizo_irq_data *irq_data = _data;
unsigned long pbm_regs = irq_data->pbm_regs;
unsigned long imap, iclr;
int ign_fixup;
int virt_irq;
int is_tomatillo;
ino &= 0x3f;
/* Now build the IRQ bucket. */
imap = schizo_ino_to_imap(pbm_regs, ino);
iclr = schizo_ino_to_iclr(pbm_regs, ino);
/* On Schizo, no inofixup occurs. This is because each
* INO has it's own IMAP register. On Psycho and Sabre
* there is only one IMAP register for each PCI slot even
* though four different INOs can be generated by each
* PCI slot.
*
* But, for JBUS variants (essentially, Tomatillo), we have
* to fixup the lowest bit of the interrupt group number.
*/
ign_fixup = 0;
is_tomatillo = (irq_data->sync_reg != 0UL);
if (is_tomatillo) {
if (irq_data->portid & 1)
ign_fixup = (1 << 6);
}
virt_irq = build_irq(ign_fixup, iclr, imap);
if (is_tomatillo) {
irq_install_pre_handler(virt_irq,
tomatillo_wsync_handler,
((irq_data->chip_version <= 4) ?
(void *) 1 : (void *) 0),
(void *) irq_data->sync_reg);
}
return virt_irq;
}
static void __schizo_irq_trans_init(struct device_node *dp, int is_tomatillo)
{
struct linux_prom64_registers *regs;
struct schizo_irq_data *irq_data;
dp->irq_trans = prom_early_alloc(sizeof(struct of_irq_controller));
dp->irq_trans->irq_build = schizo_irq_build;
irq_data = prom_early_alloc(sizeof(struct schizo_irq_data));
regs = of_get_property(dp, "reg", NULL);
dp->irq_trans->data = irq_data;
irq_data->pbm_regs = regs[0].phys_addr;
if (is_tomatillo)
irq_data->sync_reg = regs[3].phys_addr + 0x1a18UL;
else
irq_data->sync_reg = 0UL;
irq_data->portid = of_getintprop_default(dp, "portid", 0);
irq_data->chip_version = of_getintprop_default(dp, "version#", 0);
}
static void schizo_irq_trans_init(struct device_node *dp)
{
__schizo_irq_trans_init(dp, 0);
}
static void tomatillo_irq_trans_init(struct device_node *dp)
{
__schizo_irq_trans_init(dp, 1);
}
static unsigned int pci_sun4v_irq_build(struct device_node *dp,
unsigned int devino,
void *_data)
{
u32 devhandle = (u32) (unsigned long) _data;
return sun4v_build_irq(devhandle, devino);
}
static void pci_sun4v_irq_trans_init(struct device_node *dp)
{
struct linux_prom64_registers *regs;
dp->irq_trans = prom_early_alloc(sizeof(struct of_irq_controller));
dp->irq_trans->irq_build = pci_sun4v_irq_build;
regs = of_get_property(dp, "reg", NULL);
dp->irq_trans->data = (void *) (unsigned long)
((regs->phys_addr >> 32UL) & 0x0fffffff);
}
#endif /* CONFIG_PCI */
#ifdef CONFIG_SBUS
/* INO number to IMAP register offset for SYSIO external IRQ's.
* This should conform to both Sunfire/Wildfire server and Fusion
* desktop designs.
*/
#define SYSIO_IMAP_SLOT0 0x2c04UL
#define SYSIO_IMAP_SLOT1 0x2c0cUL
#define SYSIO_IMAP_SLOT2 0x2c14UL
#define SYSIO_IMAP_SLOT3 0x2c1cUL
#define SYSIO_IMAP_SCSI 0x3004UL
#define SYSIO_IMAP_ETH 0x300cUL
#define SYSIO_IMAP_BPP 0x3014UL
#define SYSIO_IMAP_AUDIO 0x301cUL
#define SYSIO_IMAP_PFAIL 0x3024UL
#define SYSIO_IMAP_KMS 0x302cUL
#define SYSIO_IMAP_FLPY 0x3034UL
#define SYSIO_IMAP_SHW 0x303cUL
#define SYSIO_IMAP_KBD 0x3044UL
#define SYSIO_IMAP_MS 0x304cUL
#define SYSIO_IMAP_SER 0x3054UL
#define SYSIO_IMAP_TIM0 0x3064UL
#define SYSIO_IMAP_TIM1 0x306cUL
#define SYSIO_IMAP_UE 0x3074UL
#define SYSIO_IMAP_CE 0x307cUL
#define SYSIO_IMAP_SBERR 0x3084UL
#define SYSIO_IMAP_PMGMT 0x308cUL
#define SYSIO_IMAP_GFX 0x3094UL
#define SYSIO_IMAP_EUPA 0x309cUL
#define bogon ((unsigned long) -1)
static unsigned long sysio_irq_offsets[] = {
/* SBUS Slot 0 --> 3, level 1 --> 7 */
SYSIO_IMAP_SLOT0, SYSIO_IMAP_SLOT0, SYSIO_IMAP_SLOT0, SYSIO_IMAP_SLOT0,
SYSIO_IMAP_SLOT0, SYSIO_IMAP_SLOT0, SYSIO_IMAP_SLOT0, SYSIO_IMAP_SLOT0,
SYSIO_IMAP_SLOT1, SYSIO_IMAP_SLOT1, SYSIO_IMAP_SLOT1, SYSIO_IMAP_SLOT1,
SYSIO_IMAP_SLOT1, SYSIO_IMAP_SLOT1, SYSIO_IMAP_SLOT1, SYSIO_IMAP_SLOT1,
SYSIO_IMAP_SLOT2, SYSIO_IMAP_SLOT2, SYSIO_IMAP_SLOT2, SYSIO_IMAP_SLOT2,
SYSIO_IMAP_SLOT2, SYSIO_IMAP_SLOT2, SYSIO_IMAP_SLOT2, SYSIO_IMAP_SLOT2,
SYSIO_IMAP_SLOT3, SYSIO_IMAP_SLOT3, SYSIO_IMAP_SLOT3, SYSIO_IMAP_SLOT3,
SYSIO_IMAP_SLOT3, SYSIO_IMAP_SLOT3, SYSIO_IMAP_SLOT3, SYSIO_IMAP_SLOT3,
/* Onboard devices (not relevant/used on SunFire). */
SYSIO_IMAP_SCSI,
SYSIO_IMAP_ETH,
SYSIO_IMAP_BPP,
bogon,
SYSIO_IMAP_AUDIO,
SYSIO_IMAP_PFAIL,
bogon,
bogon,
SYSIO_IMAP_KMS,
SYSIO_IMAP_FLPY,
SYSIO_IMAP_SHW,
SYSIO_IMAP_KBD,
SYSIO_IMAP_MS,
SYSIO_IMAP_SER,
bogon,
bogon,
SYSIO_IMAP_TIM0,
SYSIO_IMAP_TIM1,
bogon,
bogon,
SYSIO_IMAP_UE,
SYSIO_IMAP_CE,
SYSIO_IMAP_SBERR,
SYSIO_IMAP_PMGMT,
SYSIO_IMAP_GFX,
SYSIO_IMAP_EUPA,
};
#undef bogon
#define NUM_SYSIO_OFFSETS ARRAY_SIZE(sysio_irq_offsets)
/* Convert Interrupt Mapping register pointer to associated
* Interrupt Clear register pointer, SYSIO specific version.
*/
#define SYSIO_ICLR_UNUSED0 0x3400UL
#define SYSIO_ICLR_SLOT0 0x340cUL
#define SYSIO_ICLR_SLOT1 0x344cUL
#define SYSIO_ICLR_SLOT2 0x348cUL
#define SYSIO_ICLR_SLOT3 0x34ccUL
static unsigned long sysio_imap_to_iclr(unsigned long imap)
{
unsigned long diff = SYSIO_ICLR_UNUSED0 - SYSIO_IMAP_SLOT0;
return imap + diff;
}
static unsigned int sbus_of_build_irq(struct device_node *dp,
unsigned int ino,
void *_data)
{
unsigned long reg_base = (unsigned long) _data;
struct linux_prom_registers *regs;
unsigned long imap, iclr;
int sbus_slot = 0;
int sbus_level = 0;
ino &= 0x3f;
regs = of_get_property(dp, "reg", NULL);
if (regs)
sbus_slot = regs->which_io;
if (ino < 0x20)
ino += (sbus_slot * 8);
imap = sysio_irq_offsets[ino];
if (imap == ((unsigned long)-1)) {
prom_printf("get_irq_translations: Bad SYSIO INO[%x]\n",
ino);
prom_halt();
}
imap += reg_base;
/* SYSIO inconsistency. For external SLOTS, we have to select
* the right ICLR register based upon the lower SBUS irq level
* bits.
*/
if (ino >= 0x20) {
iclr = sysio_imap_to_iclr(imap);
} else {
sbus_level = ino & 0x7;
switch(sbus_slot) {
case 0:
iclr = reg_base + SYSIO_ICLR_SLOT0;
break;
case 1:
iclr = reg_base + SYSIO_ICLR_SLOT1;
break;
case 2:
iclr = reg_base + SYSIO_ICLR_SLOT2;
break;
default:
case 3:
iclr = reg_base + SYSIO_ICLR_SLOT3;
break;
};
iclr += ((unsigned long)sbus_level - 1UL) * 8UL;
}
return build_irq(sbus_level, iclr, imap);
}
static void sbus_irq_trans_init(struct device_node *dp)
{
struct linux_prom64_registers *regs;
dp->irq_trans = prom_early_alloc(sizeof(struct of_irq_controller));
dp->irq_trans->irq_build = sbus_of_build_irq;
regs = of_get_property(dp, "reg", NULL);
dp->irq_trans->data = (void *) (unsigned long) regs->phys_addr;
}
#endif /* CONFIG_SBUS */
static unsigned int central_build_irq(struct device_node *dp,
unsigned int ino,
void *_data)
{
struct device_node *central_dp = _data;
struct of_device *central_op = of_find_device_by_node(central_dp);
struct resource *res;
unsigned long imap, iclr;
u32 tmp;
if (!strcmp(dp->name, "eeprom")) {
res = &central_op->resource[5];
} else if (!strcmp(dp->name, "zs")) {
res = &central_op->resource[4];
} else if (!strcmp(dp->name, "clock-board")) {
res = &central_op->resource[3];
} else {
return ino;
}
imap = res->start + 0x00UL;
iclr = res->start + 0x10UL;
/* Set the INO state to idle, and disable. */
upa_writel(0, iclr);
upa_readl(iclr);
tmp = upa_readl(imap);
tmp &= ~0x80000000;
upa_writel(tmp, imap);
return build_irq(0, iclr, imap);
}
static void central_irq_trans_init(struct device_node *dp)
{
dp->irq_trans = prom_early_alloc(sizeof(struct of_irq_controller));
dp->irq_trans->irq_build = central_build_irq;
dp->irq_trans->data = dp;
}
struct irq_trans {
const char *name;
void (*init)(struct device_node *);
};
#ifdef CONFIG_PCI
static struct irq_trans pci_irq_trans_table[] = {
{ "SUNW,sabre", sabre_irq_trans_init },
{ "pci108e,a000", sabre_irq_trans_init },
{ "pci108e,a001", sabre_irq_trans_init },
{ "SUNW,psycho", psycho_irq_trans_init },
{ "pci108e,8000", psycho_irq_trans_init },
{ "SUNW,schizo", schizo_irq_trans_init },
{ "pci108e,8001", schizo_irq_trans_init },
{ "SUNW,schizo+", schizo_irq_trans_init },
{ "pci108e,8002", schizo_irq_trans_init },
{ "SUNW,tomatillo", tomatillo_irq_trans_init },
{ "pci108e,a801", tomatillo_irq_trans_init },
{ "SUNW,sun4v-pci", pci_sun4v_irq_trans_init },
};
#endif
static unsigned int sun4v_vdev_irq_build(struct device_node *dp,
unsigned int devino,
void *_data)
{
u32 devhandle = (u32) (unsigned long) _data;
return sun4v_build_irq(devhandle, devino);
}
static void sun4v_vdev_irq_trans_init(struct device_node *dp)
{
struct linux_prom64_registers *regs;
dp->irq_trans = prom_early_alloc(sizeof(struct of_irq_controller));
dp->irq_trans->irq_build = sun4v_vdev_irq_build;
regs = of_get_property(dp, "reg", NULL);
dp->irq_trans->data = (void *) (unsigned long)
((regs->phys_addr >> 32UL) & 0x0fffffff);
}
static void irq_trans_init(struct device_node *dp)
{
#ifdef CONFIG_PCI
const char *model;
int i;
#endif
#ifdef CONFIG_PCI
model = of_get_property(dp, "model", NULL);
if (!model)
model = of_get_property(dp, "compatible", NULL);
if (model) {
for (i = 0; i < ARRAY_SIZE(pci_irq_trans_table); i++) {
struct irq_trans *t = &pci_irq_trans_table[i];
if (!strcmp(model, t->name))
return t->init(dp);
}
}
#endif
#ifdef CONFIG_SBUS
if (!strcmp(dp->name, "sbus") ||
!strcmp(dp->name, "sbi"))
return sbus_irq_trans_init(dp);
#endif
if (!strcmp(dp->name, "fhc") &&
!strcmp(dp->parent->name, "central"))
return central_irq_trans_init(dp);
if (!strcmp(dp->name, "virtual-devices"))
return sun4v_vdev_irq_trans_init(dp);
}
static int is_root_node(const struct device_node *dp)
{
if (!dp)
return 0;
return (dp->parent == NULL);
}
/* The following routines deal with the black magic of fully naming a
* node.
*
* Certain well known named nodes are just the simple name string.
*
* Actual devices have an address specifier appended to the base name
* string, like this "foo@addr". The "addr" can be in any number of
* formats, and the platform plus the type of the node determine the
* format and how it is constructed.
*
* For children of the ROOT node, the naming convention is fixed and
* determined by whether this is a sun4u or sun4v system.
*
* For children of other nodes, it is bus type specific. So
* we walk up the tree until we discover a "device_type" property
* we recognize and we go from there.
*
* As an example, the boot device on my workstation has a full path:
*
* /pci@1e,600000/ide@d/disk@0,0:c
*/
static void __init sun4v_path_component(struct device_node *dp, char *tmp_buf)
{
struct linux_prom64_registers *regs;
struct property *rprop;
u32 high_bits, low_bits, type;
rprop = of_find_property(dp, "reg", NULL);
if (!rprop)
return;
regs = rprop->value;
if (!is_root_node(dp->parent)) {
sprintf(tmp_buf, "%s@%x,%x",
dp->name,
(unsigned int) (regs->phys_addr >> 32UL),
(unsigned int) (regs->phys_addr & 0xffffffffUL));
return;
}
type = regs->phys_addr >> 60UL;
high_bits = (regs->phys_addr >> 32UL) & 0x0fffffffUL;
low_bits = (regs->phys_addr & 0xffffffffUL);
if (type == 0 || type == 8) {
const char *prefix = (type == 0) ? "m" : "i";
if (low_bits)
sprintf(tmp_buf, "%s@%s%x,%x",
dp->name, prefix,
high_bits, low_bits);
else
sprintf(tmp_buf, "%s@%s%x",
dp->name,
prefix,
high_bits);
} else if (type == 12) {
sprintf(tmp_buf, "%s@%x",
dp->name, high_bits);
}
}
static void __init sun4u_path_component(struct device_node *dp, char *tmp_buf)
{
struct linux_prom64_registers *regs;
struct property *prop;
prop = of_find_property(dp, "reg", NULL);
if (!prop)
return;
regs = prop->value;
if (!is_root_node(dp->parent)) {
sprintf(tmp_buf, "%s@%x,%x",
dp->name,
(unsigned int) (regs->phys_addr >> 32UL),
(unsigned int) (regs->phys_addr & 0xffffffffUL));
return;
}
prop = of_find_property(dp, "upa-portid", NULL);
if (!prop)
prop = of_find_property(dp, "portid", NULL);
if (prop) {
unsigned long mask = 0xffffffffUL;
if (tlb_type >= cheetah)
mask = 0x7fffff;
sprintf(tmp_buf, "%s@%x,%x",
dp->name,
*(u32 *)prop->value,
(unsigned int) (regs->phys_addr & mask));
}
}
/* "name@slot,offset" */
static void __init sbus_path_component(struct device_node *dp, char *tmp_buf)
{
struct linux_prom_registers *regs;
struct property *prop;
prop = of_find_property(dp, "reg", NULL);
if (!prop)
return;
regs = prop->value;
sprintf(tmp_buf, "%s@%x,%x",
dp->name,
regs->which_io,
regs->phys_addr);
}
/* "name@devnum[,func]" */
static void __init pci_path_component(struct device_node *dp, char *tmp_buf)
{
struct linux_prom_pci_registers *regs;
struct property *prop;
unsigned int devfn;
prop = of_find_property(dp, "reg", NULL);
if (!prop)
return;
regs = prop->value;
devfn = (regs->phys_hi >> 8) & 0xff;
if (devfn & 0x07) {
sprintf(tmp_buf, "%s@%x,%x",
dp->name,
devfn >> 3,
devfn & 0x07);
} else {
sprintf(tmp_buf, "%s@%x",
dp->name,
devfn >> 3);
}
}
/* "name@UPA_PORTID,offset" */
static void __init upa_path_component(struct device_node *dp, char *tmp_buf)
{
struct linux_prom64_registers *regs;
struct property *prop;
prop = of_find_property(dp, "reg", NULL);
if (!prop)
return;
regs = prop->value;
prop = of_find_property(dp, "upa-portid", NULL);
if (!prop)
return;
sprintf(tmp_buf, "%s@%x,%x",
dp->name,
*(u32 *) prop->value,
(unsigned int) (regs->phys_addr & 0xffffffffUL));
}
/* "name@reg" */
static void __init vdev_path_component(struct device_node *dp, char *tmp_buf)
{
struct property *prop;
u32 *regs;
prop = of_find_property(dp, "reg", NULL);
if (!prop)
return;
regs = prop->value;
sprintf(tmp_buf, "%s@%x", dp->name, *regs);
}
/* "name@addrhi,addrlo" */
static void __init ebus_path_component(struct device_node *dp, char *tmp_buf)
{
struct linux_prom64_registers *regs;
struct property *prop;
prop = of_find_property(dp, "reg", NULL);
if (!prop)
return;
regs = prop->value;
sprintf(tmp_buf, "%s@%x,%x",
dp->name,
(unsigned int) (regs->phys_addr >> 32UL),
(unsigned int) (regs->phys_addr & 0xffffffffUL));
}
/* "name@bus,addr" */
static void __init i2c_path_component(struct device_node *dp, char *tmp_buf)
{
struct property *prop;
u32 *regs;
prop = of_find_property(dp, "reg", NULL);
if (!prop)
return;
regs = prop->value;
/* This actually isn't right... should look at the #address-cells
* property of the i2c bus node etc. etc.
*/
sprintf(tmp_buf, "%s@%x,%x",
dp->name, regs[0], regs[1]);
}
/* "name@reg0[,reg1]" */
static void __init usb_path_component(struct device_node *dp, char *tmp_buf)
{
struct property *prop;
u32 *regs;
prop = of_find_property(dp, "reg", NULL);
if (!prop)
return;
regs = prop->value;
if (prop->length == sizeof(u32) || regs[1] == 1) {
sprintf(tmp_buf, "%s@%x",
dp->name, regs[0]);
} else {
sprintf(tmp_buf, "%s@%x,%x",
dp->name, regs[0], regs[1]);
}
}
/* "name@reg0reg1[,reg2reg3]" */
static void __init ieee1394_path_component(struct device_node *dp, char *tmp_buf)
{
struct property *prop;
u32 *regs;
prop = of_find_property(dp, "reg", NULL);
if (!prop)
return;
regs = prop->value;
if (regs[2] || regs[3]) {
sprintf(tmp_buf, "%s@%08x%08x,%04x%08x",
dp->name, regs[0], regs[1], regs[2], regs[3]);
} else {
sprintf(tmp_buf, "%s@%08x%08x",
dp->name, regs[0], regs[1]);
}
}
static void __init __build_path_component(struct device_node *dp, char *tmp_buf)
{
struct device_node *parent = dp->parent;
if (parent != NULL) {
if (!strcmp(parent->type, "pci") ||
!strcmp(parent->type, "pciex"))
return pci_path_component(dp, tmp_buf);
if (!strcmp(parent->type, "sbus"))
return sbus_path_component(dp, tmp_buf);
if (!strcmp(parent->type, "upa"))
return upa_path_component(dp, tmp_buf);
if (!strcmp(parent->type, "ebus"))
return ebus_path_component(dp, tmp_buf);
if (!strcmp(parent->name, "usb") ||
!strcmp(parent->name, "hub"))
return usb_path_component(dp, tmp_buf);
if (!strcmp(parent->type, "i2c"))
return i2c_path_component(dp, tmp_buf);
if (!strcmp(parent->type, "firewire"))
return ieee1394_path_component(dp, tmp_buf);
if (!strcmp(parent->type, "virtual-devices"))
return vdev_path_component(dp, tmp_buf);
/* "isa" is handled with platform naming */
}
/* Use platform naming convention. */
if (tlb_type == hypervisor)
return sun4v_path_component(dp, tmp_buf);
else
return sun4u_path_component(dp, tmp_buf);
}
static char * __init build_path_component(struct device_node *dp)
{
char tmp_buf[64], *n;
tmp_buf[0] = '\0';
__build_path_component(dp, tmp_buf);
if (tmp_buf[0] == '\0')
strcpy(tmp_buf, dp->name);
n = prom_early_alloc(strlen(tmp_buf) + 1);
strcpy(n, tmp_buf);
return n;
}
static char * __init build_full_name(struct device_node *dp)
{
int len, ourlen, plen;
char *n;
plen = strlen(dp->parent->full_name);
ourlen = strlen(dp->path_component_name);
len = ourlen + plen + 2;
n = prom_early_alloc(len);
strcpy(n, dp->parent->full_name);
if (!is_root_node(dp->parent)) {
strcpy(n + plen, "/");
plen++;
}
strcpy(n + plen, dp->path_component_name);
return n;
}
static unsigned int unique_id;
static struct property * __init build_one_prop(phandle node, char *prev, char *special_name, void *special_val, int special_len)
{
static struct property *tmp = NULL;
struct property *p;
if (tmp) {
p = tmp;
memset(p, 0, sizeof(*p) + 32);
tmp = NULL;
} else {
p = prom_early_alloc(sizeof(struct property) + 32);
p->unique_id = unique_id++;
}
p->name = (char *) (p + 1);
if (special_name) {
strcpy(p->name, special_name);
p->length = special_len;
p->value = prom_early_alloc(special_len);
memcpy(p->value, special_val, special_len);
} else {
if (prev == NULL) {
prom_firstprop(node, p->name);
} else {
prom_nextprop(node, prev, p->name);
}
if (strlen(p->name) == 0) {
tmp = p;
return NULL;
}
p->length = prom_getproplen(node, p->name);
if (p->length <= 0) {
p->length = 0;
} else {
p->value = prom_early_alloc(p->length + 1);
prom_getproperty(node, p->name, p->value, p->length);
((unsigned char *)p->value)[p->length] = '\0';
}
}
return p;
}
static struct property * __init build_prop_list(phandle node)
{
struct property *head, *tail;
head = tail = build_one_prop(node, NULL,
".node", &node, sizeof(node));
tail->next = build_one_prop(node, NULL, NULL, NULL, 0);
tail = tail->next;
while(tail) {
tail->next = build_one_prop(node, tail->name,
NULL, NULL, 0);
tail = tail->next;
}
return head;
}
static char * __init get_one_property(phandle node, const char *name)
{
char *buf = "<NULL>";
int len;
len = prom_getproplen(node, name);
if (len > 0) {
buf = prom_early_alloc(len);
prom_getproperty(node, name, buf, len);
}
return buf;
}
static struct device_node * __init create_node(phandle node, struct device_node *parent)
{
struct device_node *dp;
if (!node)
return NULL;
dp = prom_early_alloc(sizeof(*dp));
dp->unique_id = unique_id++;
dp->parent = parent;
kref_init(&dp->kref);
dp->name = get_one_property(node, "name");
dp->type = get_one_property(node, "device_type");
dp->node = node;
dp->properties = build_prop_list(node);
irq_trans_init(dp);
return dp;
}
static struct device_node * __init build_tree(struct device_node *parent, phandle node, struct device_node ***nextp)
{
struct device_node *dp;
dp = create_node(node, parent);
if (dp) {
*(*nextp) = dp;
*nextp = &dp->allnext;
dp->path_component_name = build_path_component(dp);
dp->full_name = build_full_name(dp);
dp->child = build_tree(dp, prom_getchild(node), nextp);
dp->sibling = build_tree(parent, prom_getsibling(node), nextp);
}
return dp;
}
void __init prom_build_devicetree(void)
{
struct device_node **nextp;
allnodes = create_node(prom_root_node, NULL);
allnodes->path_component_name = "";
allnodes->full_name = "/";
nextp = &allnodes->allnext;
allnodes->child = build_tree(allnodes,
prom_getchild(allnodes->node),
&nextp);
printk("PROM: Built device tree with %u bytes of memory.\n",
prom_early_allocated);
}