NFS: Ensure that nfs_link() instantiates the dentry correctly

[linux-2.6/mini2440.git] / arch / ppc / syslib / prom_init.c

/*
 * Note that prom_init() and anything called from prom_init()
 * may be running at an address that is different from the address
 * that it was linked at.  References to static data items are
 * handled by compiling this file with -mrelocatable-lib.
 */

#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/version.h>
#include <linux/threads.h>
#include <linux/spinlock.h>
#include <linux/ioport.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/bitops.h>

#include <asm/sections.h>
#include <asm/prom.h>
#include <asm/page.h>
#include <asm/irq.h>
#include <asm/io.h>
#include <asm/smp.h>
#include <asm/bootx.h>
#include <asm/system.h>
#include <asm/mmu.h>
#include <asm/pgtable.h>
#include <asm/bootinfo.h>
#include <asm/btext.h>
#include <asm/pci-bridge.h>
#include <asm/open_pic.h>
#include <asm/cacheflush.h>

#ifdef CONFIG_LOGO_LINUX_CLUT224
#include <linux/linux_logo.h>
extern const struct linux_logo logo_linux_clut224;
#endif

/*
 * Properties whose value is longer than this get excluded from our
 * copy of the device tree.  This way we don't waste space storing
 * things like "driver,AAPL,MacOS,PowerPC" properties.  But this value
 * does need to be big enough to ensure that we don't lose things
 * like the interrupt-map property on a PCI-PCI bridge.
 */
#define MAX_PROPERTY_LENGTH     4096

#ifndef FB_MAX                  /* avoid pulling in all of the fb stuff */
#define FB_MAX  8
#endif

#define ALIGNUL(x) (((x) + sizeof(unsigned long)-1) & -sizeof(unsigned long))

typedef u32 prom_arg_t;

struct prom_args {
        const char *service;
        int nargs;
        int nret;
        prom_arg_t args[10];
};

struct pci_address {
        unsigned a_hi;
        unsigned a_mid;
        unsigned a_lo;
};

struct pci_reg_property {
        struct pci_address addr;
        unsigned size_hi;
        unsigned size_lo;
};

struct pci_range {
        struct pci_address addr;
        unsigned phys;
        unsigned size_hi;
        unsigned size_lo;
};

struct isa_reg_property {
        unsigned space;
        unsigned address;
        unsigned size;
};

struct pci_intr_map {
        struct pci_address addr;
        unsigned dunno;
        phandle int_ctrler;
        unsigned intr;
};

static void prom_exit(void);
static int  call_prom(const char *service, int nargs, int nret, ...);
static int  call_prom_ret(const char *service, int nargs, int nret,
                          prom_arg_t *rets, ...);
static void prom_print_hex(unsigned int v);
static int  prom_set_color(ihandle ih, int i, int r, int g, int b);
static int  prom_next_node(phandle *nodep);
static unsigned long check_display(unsigned long mem);
static void setup_disp_fake_bi(ihandle dp);
static unsigned long copy_device_tree(unsigned long mem_start,
                                unsigned long mem_end);
static unsigned long inspect_node(phandle node, struct device_node *dad,
                                unsigned long mem_start, unsigned long mem_end,
                                struct device_node ***allnextpp);
static void prom_hold_cpus(unsigned long mem);
static void prom_instantiate_rtas(void);
static void * early_get_property(unsigned long base, unsigned long node,
                                char *prop);

prom_entry prom __initdata;
ihandle prom_chosen __initdata;
ihandle prom_stdout __initdata;

static char *prom_display_paths[FB_MAX] __initdata;
static phandle prom_display_nodes[FB_MAX] __initdata;
static unsigned int prom_num_displays __initdata;
static ihandle prom_disp_node __initdata;
char *of_stdout_device __initdata;

unsigned int rtas_data;   /* physical pointer */
unsigned int rtas_entry;  /* physical pointer */
unsigned int rtas_size;
unsigned int old_rtas;

boot_infos_t *boot_infos;
char *bootpath;
char *bootdevice;
struct device_node *allnodes;

extern char *klimit;

static void __init
prom_exit(void)
{
        struct prom_args args;

        args.service = "exit";
        args.nargs = 0;
        args.nret = 0;
        prom(&args);
        for (;;)                        /* should never get here */
                ;
}

static int __init
call_prom(const char *service, int nargs, int nret, ...)
{
        va_list list;
        int i;
        struct prom_args prom_args;

        prom_args.service = service;
        prom_args.nargs = nargs;
        prom_args.nret = nret;
        va_start(list, nret);
        for (i = 0; i < nargs; ++i)
                prom_args.args[i] = va_arg(list, prom_arg_t);
        va_end(list);
        for (i = 0; i < nret; ++i)
                prom_args.args[i + nargs] = 0;
        prom(&prom_args);
        return prom_args.args[nargs];
}

static int __init
call_prom_ret(const char *service, int nargs, int nret, prom_arg_t *rets, ...)
{
        va_list list;
        int i;
        struct prom_args prom_args;

        prom_args.service = service;
        prom_args.nargs = nargs;
        prom_args.nret = nret;
        va_start(list, rets);
        for (i = 0; i < nargs; ++i)
                prom_args.args[i] = va_arg(list, int);
        va_end(list);
        for (i = 0; i < nret; ++i)
                prom_args.args[i + nargs] = 0;
        prom(&prom_args);
        for (i = 1; i < nret; ++i)
                rets[i-1] = prom_args.args[nargs + i];
        return prom_args.args[nargs];
}

void __init
prom_print(const char *msg)
{
        const char *p, *q;

        if (prom_stdout == 0)
                return;

        for (p = msg; *p != 0; p = q) {
                for (q = p; *q != 0 && *q != '\n'; ++q)
                        ;
                if (q > p)
                        call_prom("write", 3, 1, prom_stdout, p, q - p);
                if (*q != 0) {
                        ++q;
                        call_prom("write", 3, 1, prom_stdout, "\r\n", 2);
                }
        }
}

static void __init
prom_print_hex(unsigned int v)
{
        char buf[16];
        int i, c;

        for (i = 0; i < 8; ++i) {
                c = (v >> ((7-i)*4)) & 0xf;
                c += (c >= 10)? ('a' - 10): '0';
                buf[i] = c;
        }
        buf[i] = ' ';
        buf[i+1] = 0;
        prom_print(buf);
}

static int __init
prom_set_color(ihandle ih, int i, int r, int g, int b)
{
        return call_prom("call-method", 6, 1, "color!", ih, i, b, g, r);
}

static int __init
prom_next_node(phandle *nodep)
{
        phandle node;

        if ((node = *nodep) != 0
            && (*nodep = call_prom("child", 1, 1, node)) != 0)
                return 1;
        if ((*nodep = call_prom("peer", 1, 1, node)) != 0)
                return 1;
        for (;;) {
                if ((node = call_prom("parent", 1, 1, node)) == 0)
                        return 0;
                if ((*nodep = call_prom("peer", 1, 1, node)) != 0)
                        return 1;
        }
}

#ifdef CONFIG_POWER4
/*
 * Set up a hash table with a set of entries in it to map the
 * first 64MB of RAM.  This is used on 64-bit machines since
 * some of them don't have BATs.
 */

static inline void make_pte(unsigned long htab, unsigned int hsize,
                            unsigned int va, unsigned int pa, int mode)
{
        unsigned int *pteg;
        unsigned int hash, i, vsid;

        vsid = ((va >> 28) * 0x111) << 12;
        hash = ((va ^ vsid) >> 5) & 0x7fff80;
        pteg = (unsigned int *)(htab + (hash & (hsize - 1)));
        for (i = 0; i < 8; ++i, pteg += 4) {
                if ((pteg[1] & 1) == 0) {
                        pteg[1] = vsid | ((va >> 16) & 0xf80) | 1;
                        pteg[3] = pa | mode;
                        break;
                }
        }
}

extern unsigned long _SDR1;
extern PTE *Hash;
extern unsigned long Hash_size;

static void __init
prom_alloc_htab(void)
{
        unsigned int hsize;
        unsigned long htab;
        unsigned int addr;

        /*
         * Because of OF bugs we can't use the "claim" client
         * interface to allocate memory for the hash table.
         * This code is only used on 64-bit PPCs, and the only
         * 64-bit PPCs at the moment are RS/6000s, and their
         * OF is based at 0xc00000 (the 12M point), so we just
         * arbitrarily use the 0x800000 - 0xc00000 region for the
         * hash table.
         *  -- paulus.
         */
        hsize = 4 << 20;        /* POWER4 has no BATs */
        htab = (8 << 20);
        call_prom("claim", 3, 1, htab, hsize, 0);
        Hash = (void *)(htab + KERNELBASE);
        Hash_size = hsize;
        _SDR1 = htab + __ilog2(hsize) - 18;

        /*
         * Put in PTEs for the first 64MB of RAM
         */
        memset((void *)htab, 0, hsize);
        for (addr = 0; addr < 0x4000000; addr += 0x1000)
                make_pte(htab, hsize, addr + KERNELBASE, addr,
                         _PAGE_ACCESSED | _PAGE_COHERENT | PP_RWXX);
#if 0 /* DEBUG stuff mapping the SCC */
        make_pte(htab, hsize, 0x80013000, 0x80013000,
                 _PAGE_ACCESSED | _PAGE_NO_CACHE | _PAGE_GUARDED | PP_RWXX);
#endif
}
#endif /* CONFIG_POWER4 */


/*
 * If we have a display that we don't know how to drive,
 * we will want to try to execute OF's open method for it
 * later.  However, OF will probably fall over if we do that
 * we've taken over the MMU.
 * So we check whether we will need to open the display,
 * and if so, open it now.
 */
static unsigned long __init
check_display(unsigned long mem)
{
        phandle node;
        ihandle ih;
        int i, j;
        char type[16], *path;
        static unsigned char default_colors[] = {
                0x00, 0x00, 0x00,
                0x00, 0x00, 0xaa,
                0x00, 0xaa, 0x00,
                0x00, 0xaa, 0xaa,
                0xaa, 0x00, 0x00,
                0xaa, 0x00, 0xaa,
                0xaa, 0xaa, 0x00,
                0xaa, 0xaa, 0xaa,
                0x55, 0x55, 0x55,
                0x55, 0x55, 0xff,
                0x55, 0xff, 0x55,
                0x55, 0xff, 0xff,
                0xff, 0x55, 0x55,
                0xff, 0x55, 0xff,
                0xff, 0xff, 0x55,
                0xff, 0xff, 0xff
        };
        const unsigned char *clut;

        prom_disp_node = 0;

        for (node = 0; prom_next_node(&node); ) {
                type[0] = 0;
                call_prom("getprop", 4, 1, node, "device_type",
                          type, sizeof(type));
                if (strcmp(type, "display") != 0)
                        continue;
                /* It seems OF doesn't null-terminate the path :-( */
                path = (char *) mem;
                memset(path, 0, 256);
                if (call_prom("package-to-path", 3, 1, node, path, 255) < 0)
                        continue;

                /*
                 * If this display is the device that OF is using for stdout,
                 * move it to the front of the list.
                 */
                mem += strlen(path) + 1;
                i = prom_num_displays++;
                if (of_stdout_device != 0 && i > 0
                    && strcmp(of_stdout_device, path) == 0) {
                        for (; i > 0; --i) {
                                prom_display_paths[i]
                                        = prom_display_paths[i-1];
                                prom_display_nodes[i]
                                        = prom_display_nodes[i-1];
                        }
                }
                prom_display_paths[i] = path;
                prom_display_nodes[i] = node;
                if (i == 0)
                        prom_disp_node = node;
                if (prom_num_displays >= FB_MAX)
                        break;
        }

        for (j=0; j<prom_num_displays; j++) {
                path = prom_display_paths[j];
                node = prom_display_nodes[j];
                prom_print("opening display ");
                prom_print(path);
                ih = call_prom("open", 1, 1, path);
                if (ih == 0 || ih == (ihandle) -1) {
                        prom_print("... failed\n");
                        for (i=j+1; i<prom_num_displays; i++) {
                                prom_display_paths[i-1] = prom_display_paths[i];
                                prom_display_nodes[i-1] = prom_display_nodes[i];
                        }
                        if (--prom_num_displays > 0) {
                                prom_disp_node = prom_display_nodes[j];
                                j--;
                        } else
                                prom_disp_node = 0;
                        continue;
                } else {
                        prom_print("... ok\n");
                        call_prom("setprop", 4, 1, node, "linux,opened", 0, 0);

                        /*
                         * Setup a usable color table when the appropriate
                         * method is available.
                         * Should update this to use set-colors.
                         */
                        clut = default_colors;
                        for (i = 0; i < 32; i++, clut += 3)
                                if (prom_set_color(ih, i, clut[0], clut[1],
                                                   clut[2]) != 0)
                                        break;

#ifdef CONFIG_LOGO_LINUX_CLUT224
                        clut = PTRRELOC(logo_linux_clut224.clut);
                        for (i = 0; i < logo_linux_clut224.clutsize;
                             i++, clut += 3)
                                if (prom_set_color(ih, i + 32, clut[0],
                                                   clut[1], clut[2]) != 0)
                                        break;
#endif /* CONFIG_LOGO_LINUX_CLUT224 */
                }
        }
        
        if (prom_stdout) {
                phandle p;
                p = call_prom("instance-to-package", 1, 1, prom_stdout);
                if (p && p != -1) {
                        type[0] = 0;
                        call_prom("getprop", 4, 1, p, "device_type",
                                  type, sizeof(type));
                        if (strcmp(type, "display") == 0)
                                call_prom("setprop", 4, 1, p, "linux,boot-display",
                                          0, 0);
                }
        }

        return ALIGNUL(mem);
}

/* This function will enable the early boot text when doing OF booting. This
 * way, xmon output should work too
 */
static void __init
setup_disp_fake_bi(ihandle dp)
{
#ifdef CONFIG_BOOTX_TEXT
        int width = 640, height = 480, depth = 8, pitch;
        unsigned address;
        struct pci_reg_property addrs[8];
        int i, naddrs;
        char name[32];
        char *getprop = "getprop";

        prom_print("Initializing fake screen: ");

        memset(name, 0, sizeof(name));
        call_prom(getprop, 4, 1, dp, "name", name, sizeof(name));
        name[sizeof(name)-1] = 0;
        prom_print(name);
        prom_print("\n");
        call_prom(getprop, 4, 1, dp, "width", &width, sizeof(width));
        call_prom(getprop, 4, 1, dp, "height", &height, sizeof(height));
        call_prom(getprop, 4, 1, dp, "depth", &depth, sizeof(depth));
        pitch = width * ((depth + 7) / 8);
        call_prom(getprop, 4, 1, dp, "linebytes",
                  &pitch, sizeof(pitch));
        if (pitch == 1)
                pitch = 0x1000;         /* for strange IBM display */
        address = 0;
        call_prom(getprop, 4, 1, dp, "address",
                  &address, sizeof(address));
        if (address == 0) {
                /* look for an assigned address with a size of >= 1MB */
                naddrs = call_prom(getprop, 4, 1, dp, "assigned-addresses",
                                   addrs, sizeof(addrs));
                naddrs /= sizeof(struct pci_reg_property);
                for (i = 0; i < naddrs; ++i) {
                        if (addrs[i].size_lo >= (1 << 20)) {
                                address = addrs[i].addr.a_lo;
                                /* use the BE aperture if possible */
                                if (addrs[i].size_lo >= (16 << 20))
                                        address += (8 << 20);
                                break;
                        }
                }
                if (address == 0) {
                        prom_print("Failed to get address\n");
                        return;
                }
        }
        /* kludge for valkyrie */
        if (strcmp(name, "valkyrie") == 0)
                address += 0x1000;

#ifdef CONFIG_POWER4
#if CONFIG_TASK_SIZE > 0x80000000
#error CONFIG_TASK_SIZE cannot be above 0x80000000 with BOOTX_TEXT on G5
#endif
        {
                extern boot_infos_t disp_bi;
                unsigned long va, pa, i, offset;
                va = 0x90000000;
                pa = address & 0xfffff000ul;
                offset = address & 0x00000fff;

                for (i=0; i<0x4000; i++) {  
                        make_pte((unsigned long)Hash - KERNELBASE, Hash_size, va, pa, 
                                 _PAGE_ACCESSED | _PAGE_NO_CACHE |
                                 _PAGE_GUARDED | PP_RWXX);
                        va += 0x1000;
                        pa += 0x1000;
                }
                btext_setup_display(width, height, depth, pitch, 0x90000000 | offset);
                disp_bi.dispDeviceBase = (u8 *)address;
        }
#else /* CONFIG_POWER4 */
        btext_setup_display(width, height, depth, pitch, address);
        btext_prepare_BAT();
#endif /* CONFIG_POWER4 */
#endif /* CONFIG_BOOTX_TEXT */
}

/*
 * Make a copy of the device tree from the PROM.
 */
static unsigned long __init
copy_device_tree(unsigned long mem_start, unsigned long mem_end)
{
        phandle root;
        unsigned long new_start;
        struct device_node **allnextp;

        root = call_prom("peer", 1, 1, (phandle)0);
        if (root == (phandle)0) {
                prom_print("couldn't get device tree root\n");
                prom_exit();
        }
        allnextp = &allnodes;
        mem_start = ALIGNUL(mem_start);
        new_start = inspect_node(root, NULL, mem_start, mem_end, &allnextp);
        *allnextp = NULL;
        return new_start;
}

static unsigned long __init
inspect_node(phandle node, struct device_node *dad,
             unsigned long mem_start, unsigned long mem_end,
             struct device_node ***allnextpp)
{
        int l;
        phandle child;
        struct device_node *np;
        struct property *pp, **prev_propp;
        char *prev_name, *namep;
        unsigned char *valp;

        np = (struct device_node *) mem_start;
        mem_start += sizeof(struct device_node);
        memset(np, 0, sizeof(*np));
        np->node = node;
        **allnextpp = PTRUNRELOC(np);
        *allnextpp = &np->allnext;
        if (dad != 0) {
                np->parent = PTRUNRELOC(dad);
                /* we temporarily use the `next' field as `last_child'. */
                if (dad->next == 0)
                        dad->child = PTRUNRELOC(np);
                else
                        dad->next->sibling = PTRUNRELOC(np);
                dad->next = np;
        }

        /* get and store all properties */
        prev_propp = &np->properties;
        prev_name = "";
        for (;;) {
                pp = (struct property *) mem_start;
                namep = (char *) (pp + 1);
                pp->name = PTRUNRELOC(namep);
                if (call_prom("nextprop", 3, 1, node, prev_name, namep) <= 0)
                        break;
                mem_start = ALIGNUL((unsigned long)namep + strlen(namep) + 1);
                prev_name = namep;
                valp = (unsigned char *) mem_start;
                pp->value = PTRUNRELOC(valp);
                pp->length = call_prom("getprop", 4, 1, node, namep,
                                       valp, mem_end - mem_start);
                if (pp->length < 0)
                        continue;
#ifdef MAX_PROPERTY_LENGTH
                if (pp->length > MAX_PROPERTY_LENGTH)
                        continue; /* ignore this property */
#endif
                mem_start = ALIGNUL(mem_start + pp->length);
                *prev_propp = PTRUNRELOC(pp);
                prev_propp = &pp->next;
        }
        if (np->node != 0) {
                /* Add a "linux,phandle" property" */
                pp = (struct property *) mem_start;
                *prev_propp = PTRUNRELOC(pp);
                prev_propp = &pp->next;
                namep = (char *) (pp + 1);
                pp->name = PTRUNRELOC(namep);
                strcpy(namep, "linux,phandle");
                mem_start = ALIGNUL((unsigned long)namep + strlen(namep) + 1);
                pp->value = (unsigned char *) PTRUNRELOC(&np->node);
                pp->length = sizeof(np->node);
        }
        *prev_propp = NULL;

        /* get the node's full name */
        l = call_prom("package-to-path", 3, 1, node,
                      mem_start, mem_end - mem_start);
        if (l >= 0) {
                char *p, *ep;

                np->full_name = PTRUNRELOC((char *) mem_start);
                *(char *)(mem_start + l) = 0;
                /* Fixup an Apple bug where they have bogus \0 chars in the
                 * middle of the path in some properties
                 */
                for (p = (char *)mem_start, ep = p + l; p < ep; p++)
                        if ((*p) == '\0') {
                                memmove(p, p+1, ep - p);
                                ep--;
                        }
                mem_start = ALIGNUL(mem_start + l + 1);
        }

        /* do all our children */
        child = call_prom("child", 1, 1, node);
        while (child != 0) {
                mem_start = inspect_node(child, np, mem_start, mem_end,
                                         allnextpp);
                child = call_prom("peer", 1, 1, child);
        }

        return mem_start;
}

unsigned long smp_chrp_cpu_nr __initdata = 0;

/*
 * With CHRP SMP we need to use the OF to start the other
 * processors so we can't wait until smp_boot_cpus (the OF is
 * trashed by then) so we have to put the processors into
 * a holding pattern controlled by the kernel (not OF) before
 * we destroy the OF.
 *
 * This uses a chunk of high memory, puts some holding pattern
 * code there and sends the other processors off to there until
 * smp_boot_cpus tells them to do something.  We do that by using
 * physical address 0x0.  The holding pattern checks that address
 * until its cpu # is there, when it is that cpu jumps to
 * __secondary_start().  smp_boot_cpus() takes care of setting those
 * values.
 *
 * We also use physical address 0x4 here to tell when a cpu
 * is in its holding pattern code.
 *
 * -- Cort
 *
 * Note that we have to do this if we have more than one CPU,
 * even if this is a UP kernel.  Otherwise when we trash OF
 * the other CPUs will start executing some random instructions
 * and crash the system.  -- paulus
 */
static void __init
prom_hold_cpus(unsigned long mem)
{
        extern void __secondary_hold(void);
        unsigned long i;
        int cpu;
        phandle node;
        char type[16], *path;
        unsigned int reg;

        /*
         * XXX: hack to make sure we're chrp, assume that if we're
         *      chrp we have a device_type property -- Cort
         */
        node = call_prom("finddevice", 1, 1, "/");
        if (call_prom("getprop", 4, 1, node,
                      "device_type", type, sizeof(type)) <= 0)
                return;

        /* copy the holding pattern code to someplace safe (0) */
        /* the holding pattern is now within the first 0x100
           bytes of the kernel image -- paulus */
        memcpy((void *)0, _stext, 0x100);
        flush_icache_range(0, 0x100);

        /* look for cpus */
        *(unsigned long *)(0x0) = 0;
        asm volatile("dcbf 0,%0": : "r" (0) : "memory");
        for (node = 0; prom_next_node(&node); ) {
                type[0] = 0;
                call_prom("getprop", 4, 1, node, "device_type",
                          type, sizeof(type));
                if (strcmp(type, "cpu") != 0)
                        continue;
                path = (char *) mem;
                memset(path, 0, 256);
                if (call_prom("package-to-path", 3, 1, node, path, 255) < 0)
                        continue;
                reg = -1;
                call_prom("getprop", 4, 1, node, "reg", &reg, sizeof(reg));
                cpu = smp_chrp_cpu_nr++;
#ifdef CONFIG_SMP
                smp_hw_index[cpu] = reg;
#endif /* CONFIG_SMP */
                /* XXX: hack - don't start cpu 0, this cpu -- Cort */
                if (cpu == 0)
                        continue;
                prom_print("starting cpu ");
                prom_print(path);
                *(ulong *)(0x4) = 0;
                call_prom("start-cpu", 3, 0, node,
                          (char *)__secondary_hold - _stext, cpu);
                prom_print("...");
                for ( i = 0 ; (i < 10000) && (*(ulong *)(0x4) == 0); i++ )
                        ;
                if (*(ulong *)(0x4) == cpu)
                        prom_print("ok\n");
                else {
                        prom_print("failed: ");
                        prom_print_hex(*(ulong *)0x4);
                        prom_print("\n");
                }
        }
}

static void __init
prom_instantiate_rtas(void)
{
        ihandle prom_rtas;
        prom_arg_t result;

        prom_rtas = call_prom("finddevice", 1, 1, "/rtas");
        if (prom_rtas == -1)
                return;

        rtas_size = 0;
        call_prom("getprop", 4, 1, prom_rtas,
                  "rtas-size", &rtas_size, sizeof(rtas_size));
        prom_print("instantiating rtas");
        if (rtas_size == 0) {
                rtas_data = 0;
        } else {
                /*
                 * Ask OF for some space for RTAS.
                 * Actually OF has bugs so we just arbitrarily
                 * use memory at the 6MB point.
                 */
                rtas_data = 6 << 20;
                prom_print(" at ");
                prom_print_hex(rtas_data);
        }

        prom_rtas = call_prom("open", 1, 1, "/rtas");
        prom_print("...");
        rtas_entry = 0;
        if (call_prom_ret("call-method", 3, 2, &result,
                          "instantiate-rtas", prom_rtas, rtas_data) == 0)
                rtas_entry = result;
        if ((rtas_entry == -1) || (rtas_entry == 0))
                prom_print(" failed\n");
        else
                prom_print(" done\n");
}

/*
 * We enter here early on, when the Open Firmware prom is still
 * handling exceptions and the MMU hash table for us.
 */
unsigned long __init
prom_init(int r3, int r4, prom_entry pp)
{
        unsigned long mem;
        ihandle prom_mmu;
        unsigned long offset = reloc_offset();
        int i, l;
        char *p, *d;
        unsigned long phys;
        prom_arg_t result[3];
        char model[32];
        phandle node;
        int rc;

        /* Default */
        phys = (unsigned long) &_stext;

        /* First get a handle for the stdout device */
        prom = pp;
        prom_chosen = call_prom("finddevice", 1, 1, "/chosen");
        if (prom_chosen == -1)
                prom_exit();
        if (call_prom("getprop", 4, 1, prom_chosen, "stdout",
                      &prom_stdout, sizeof(prom_stdout)) <= 0)
                prom_exit();

        /* Get the full OF pathname of the stdout device */
        mem = (unsigned long) klimit + offset;
        p = (char *) mem;
        memset(p, 0, 256);
        call_prom("instance-to-path", 3, 1, prom_stdout, p, 255);
        of_stdout_device = p;
        mem += strlen(p) + 1;

        /* Get the boot device and translate it to a full OF pathname. */
        p = (char *) mem;
        l = call_prom("getprop", 4, 1, prom_chosen, "bootpath", p, 1<<20);
        if (l > 0) {
                p[l] = 0;       /* should already be null-terminated */
                bootpath = PTRUNRELOC(p);
                mem += l + 1;
                d = (char *) mem;
                *d = 0;
                call_prom("canon", 3, 1, p, d, 1<<20);
                bootdevice = PTRUNRELOC(d);
                mem = ALIGNUL(mem + strlen(d) + 1);
        }

        prom_instantiate_rtas();

#ifdef CONFIG_POWER4
        /*
         * Find out how much memory we have and allocate a
         * suitably-sized hash table.
         */
        prom_alloc_htab();
#endif
        mem = check_display(mem);

        prom_print("copying OF device tree...");
        mem = copy_device_tree(mem, mem + (1<<20));
        prom_print("done\n");

        prom_hold_cpus(mem);

        klimit = (char *) (mem - offset);

        node = call_prom("finddevice", 1, 1, "/");
        rc = call_prom("getprop", 4, 1, node, "model", model, sizeof(model));
        if (rc > 0 && !strncmp (model, "Pegasos", 7)
                && strncmp (model, "Pegasos2", 8)) {
                /* Pegasos 1 has a broken translate method in the OF,
                 * and furthermore the BATs are mapped 1:1 so the phys
                 * address calculated above is correct, so let's use
                 * it directly.
                 */
        } else if (offset == 0) {
                /* If we are already running at 0xc0000000, we assume we were
                 * loaded by an OF bootloader which did set a BAT for us.
                 * This breaks OF translate so we force phys to be 0.
                 */
                prom_print("(already at 0xc0000000) phys=0\n");
                phys = 0;
        } else if (call_prom("getprop", 4, 1, prom_chosen, "mmu",
                             &prom_mmu, sizeof(prom_mmu)) <= 0) {
                prom_print(" no MMU found\n");
        } else if (call_prom_ret("call-method", 4, 4, result, "translate",
                                 prom_mmu, &_stext, 1) != 0) {
                prom_print(" (translate failed)\n");
        } else {
                /* We assume the phys. address size is 3 cells */
                phys = result[2];
        }

        if (prom_disp_node != 0)
                setup_disp_fake_bi(prom_disp_node);

        /* Use quiesce call to get OF to shut down any devices it's using */
        prom_print("Calling quiesce ...\n");
        call_prom("quiesce", 0, 0);

        /* Relocate various pointers which will be used once the
           kernel is running at the address it was linked at. */
        for (i = 0; i < prom_num_displays; ++i)
                prom_display_paths[i] = PTRUNRELOC(prom_display_paths[i]);

#ifdef CONFIG_SERIAL_CORE_CONSOLE
        /* Relocate the of stdout for console autodetection */
        of_stdout_device = PTRUNRELOC(of_stdout_device);
#endif

        prom_print("returning 0x");
        prom_print_hex(phys);
        prom_print("from prom_init\n");
        prom_stdout = 0;

        return phys;
}

/*
 * early_get_property is used to access the device tree image prepared
 * by BootX very early on, before the pointers in it have been relocated.
 */
static void * __init
early_get_property(unsigned long base, unsigned long node, char *prop)
{
        struct device_node *np = (struct device_node *)(base + node);
        struct property *pp;

        for (pp = np->properties; pp != 0; pp = pp->next) {
                pp = (struct property *) (base + (unsigned long)pp);
                if (strcmp((char *)((unsigned long)pp->name + base),
                           prop) == 0) {
                        return (void *)((unsigned long)pp->value + base);
                }
        }
        return NULL;
}

/* Is boot-info compatible ? */
#define BOOT_INFO_IS_COMPATIBLE(bi)             ((bi)->compatible_version <= BOOT_INFO_VERSION)
#define BOOT_INFO_IS_V2_COMPATIBLE(bi)  ((bi)->version >= 2)
#define BOOT_INFO_IS_V4_COMPATIBLE(bi)  ((bi)->version >= 4)

void __init
bootx_init(unsigned long r4, unsigned long phys)
{
        boot_infos_t *bi = (boot_infos_t *) r4;
        unsigned long space;
        unsigned long ptr, x;
        char *model;

        boot_infos = PTRUNRELOC(bi);
        if (!BOOT_INFO_IS_V2_COMPATIBLE(bi))
                bi->logicalDisplayBase = NULL;

#ifdef CONFIG_BOOTX_TEXT
        btext_init(bi);

        /*
         * Test if boot-info is compatible.  Done only in config
         * CONFIG_BOOTX_TEXT since there is nothing much we can do
         * with an incompatible version, except display a message
         * and eventually hang the processor...
         *
         * I'll try to keep enough of boot-info compatible in the
         * future to always allow display of this message;
         */
        if (!BOOT_INFO_IS_COMPATIBLE(bi)) {
                btext_drawstring(" !!! WARNING - Incompatible version of BootX !!!\n\n\n");
                btext_flushscreen();
        }
#endif  /* CONFIG_BOOTX_TEXT */

        /* New BootX enters kernel with MMU off, i/os are not allowed
           here. This hack will have been done by the boostrap anyway.
        */
        if (bi->version < 4) {
                /*
                 * XXX If this is an iMac, turn off the USB controller.
                 */
                model = (char *) early_get_property
                        (r4 + bi->deviceTreeOffset, 4, "model");
                if (model
                    && (strcmp(model, "iMac,1") == 0
                        || strcmp(model, "PowerMac1,1") == 0)) {
                        out_le32((unsigned *)0x80880008, 1);    /* XXX */
                }
        }

        /* Move klimit to enclose device tree, args, ramdisk, etc... */
        if (bi->version < 5) {
                space = bi->deviceTreeOffset + bi->deviceTreeSize;
                if (bi->ramDisk)
                        space = bi->ramDisk + bi->ramDiskSize;
        } else
                space = bi->totalParamsSize;
        klimit = PTRUNRELOC((char *) bi + space);

        /* New BootX will have flushed all TLBs and enters kernel with
           MMU switched OFF, so this should not be useful anymore.
        */
        if (bi->version < 4) {
                /*
                 * Touch each page to make sure the PTEs for them
                 * are in the hash table - the aim is to try to avoid
                 * getting DSI exceptions while copying the kernel image.
                 */
                for (ptr = ((unsigned long) &_stext) & PAGE_MASK;
                     ptr < (unsigned long)bi + space; ptr += PAGE_SIZE)
                        x = *(volatile unsigned long *)ptr;
        }

#ifdef CONFIG_BOOTX_TEXT
        /*
         * Note that after we call btext_prepare_BAT, we can't do
         * prom_draw*, flushscreen or clearscreen until we turn the MMU
         * on, since btext_prepare_BAT sets disp_bi.logicalDisplayBase
         * to a virtual address.
         */
        btext_prepare_BAT();
#endif
}