powerpc: Merge in the ppc64 version of the prom code.

This brings in the ppc64 version of prom_init.c, prom.c and btext.c
and makes them work for ppc32.  This also brings in the new calling
convention, where the first entry to the kernel (with r5 != 0) goes
to the prom_init code, which then restarts from the beginning (with
r5 == 0) after it has done its stuff.

For now this also brings in the ppc32 version of setup.c.  It also
merges lmb.h.

Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 2126 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c
new file mode 100644
index 00000000000..e01cda1454c
--- /dev/null
+++ b/arch/powerpc/kernel/prom_init.c
@@ -0,0 +1,2126 @@
+/*
+ * Procedures for interfacing to Open Firmware.
+ *
+ * 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_PROM
+
+#include <stdarg.h>
+#include <linux/config.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/proc_fs.h>
+#include <linux/stringify.h>
+#include <linux/delay.h>
+#include <linux/initrd.h>
+#include <linux/bitops.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/smp.h>
+#include <asm/system.h>
+#include <asm/mmu.h>
+#include <asm/pgtable.h>
+#include <asm/pci.h>
+#include <asm/iommu.h>
+#include <asm/bootinfo.h>
+#include <asm/btext.h>
+#include <asm/sections.h>
+#include <asm/machdep.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 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	(1UL * 1024 * 1024)
+
+/*
+ * Eventually bump that one up
+ */
+#define DEVTREE_CHUNK_SIZE	0x100000
+
+/*
+ * This is the size of the local memory reserve map that gets copied
+ * into the boot params passed to the kernel. That size is totally
+ * flexible as the kernel just reads the list until it encounters an
+ * entry with size 0, so it can be changed without breaking binary
+ * compatibility
+ */
+#define MEM_RESERVE_MAP_SIZE	8
+
+/*
+ * prom_init() is called very early on, before the kernel text
+ * and data have been mapped to KERNELBASE.  At this point the code
+ * is running at whatever address it has been loaded at.
+ * On ppc32 we compile with -mrelocatable, which means that references
+ * to extern and static variables get relocated automatically.
+ * On ppc64 we have to relocate the references explicitly with
+ * RELOC.  (Note that strings count as static variables.)
+ *
+ * Because OF may have mapped I/O devices into the area starting at
+ * KERNELBASE, particularly on CHRP machines, we can't safely call
+ * OF once the kernel has been mapped to KERNELBASE.  Therefore all
+ * OF calls must be done within prom_init().
+ *
+ * ADDR is used in calls to call_prom.  The 4th and following
+ * arguments to call_prom should be 32-bit values.
+ * On ppc64, 64 bit values are truncated to 32 bits (and
+ * fortunately don't get interpreted as two arguments).
+ */
+#ifdef CONFIG_PPC64
+#define RELOC(x)        (*PTRRELOC(&(x)))
+#define ADDR(x)		(u32) add_reloc_offset((unsigned long)(x))
+#else
+#define RELOC(x)	(x)
+#define ADDR(x)		(u32) (x)
+#endif
+
+#define PROM_BUG() do {						\
+        prom_printf("kernel BUG at %s line 0x%x!\n",		\
+		    RELOC(__FILE__), __LINE__);			\
+        __asm__ __volatile__(".long " BUG_ILLEGAL_INSTR);	\
+} while (0)
+
+#ifdef DEBUG_PROM
+#define prom_debug(x...)	prom_printf(x)
+#else
+#define prom_debug(x...)
+#endif
+
+#ifdef CONFIG_PPC32
+#define PLATFORM_POWERMAC	_MACH_Pmac
+#define PLATFORM_CHRP		_MACH_chrp
+#endif
+
+
+typedef u32 prom_arg_t;
+
+struct prom_args {
+        u32 service;
+        u32 nargs;
+        u32 nret;
+        prom_arg_t args[10];
+};
+
+struct prom_t {
+	ihandle root;
+	ihandle chosen;
+	int cpu;
+	ihandle stdout;
+};
+
+struct mem_map_entry {
+	unsigned long	base;
+	unsigned long	size;
+};
+
+typedef u32 cell_t;
+
+extern void __start(unsigned long r3, unsigned long r4, unsigned long r5);
+
+#ifdef CONFIG_PPC64
+extern void enter_prom(struct prom_args *args, unsigned long entry);
+#else
+static inline void enter_prom(struct prom_args *args, unsigned long entry)
+{
+	((void (*)(struct prom_args *))entry)(args);
+}
+#endif
+
+extern void copy_and_flush(unsigned long dest, unsigned long src,
+			   unsigned long size, unsigned long offset);
+
+/* prom structure */
+static struct prom_t __initdata prom;
+
+static unsigned long prom_entry __initdata;
+
+#define PROM_SCRATCH_SIZE 256
+
+static char __initdata of_stdout_device[256];
+static char __initdata prom_scratch[PROM_SCRATCH_SIZE];
+
+static unsigned long __initdata dt_header_start;
+static unsigned long __initdata dt_struct_start, dt_struct_end;
+static unsigned long __initdata dt_string_start, dt_string_end;
+
+static unsigned long __initdata prom_initrd_start, prom_initrd_end;
+
+#ifdef CONFIG_PPC64
+static int __initdata iommu_force_on;
+static int __initdata ppc64_iommu_off;
+static unsigned long __initdata prom_tce_alloc_start;
+static unsigned long __initdata prom_tce_alloc_end;
+#endif
+
+static int __initdata of_platform;
+
+static char __initdata prom_cmd_line[COMMAND_LINE_SIZE];
+
+static unsigned long __initdata prom_memory_limit;
+
+static unsigned long __initdata alloc_top;
+static unsigned long __initdata alloc_top_high;
+static unsigned long __initdata alloc_bottom;
+static unsigned long __initdata rmo_top;
+static unsigned long __initdata ram_top;
+
+static struct mem_map_entry __initdata mem_reserve_map[MEM_RESERVE_MAP_SIZE];
+static int __initdata mem_reserve_cnt;
+
+static cell_t __initdata regbuf[1024];
+
+
+#define MAX_CPU_THREADS 2
+
+/* TO GO */
+#ifdef CONFIG_HMT
+struct {
+	unsigned int pir;
+	unsigned int threadid;
+} hmt_thread_data[NR_CPUS];
+#endif /* CONFIG_HMT */
+
+/*
+ * Error results ... some OF calls will return "-1" on error, some
+ * will return 0, some will return either. To simplify, here are
+ * macros to use with any ihandle or phandle return value to check if
+ * it is valid
+ */
+
+#define PROM_ERROR		(-1u)
+#define PHANDLE_VALID(p)	((p) != 0 && (p) != PROM_ERROR)
+#define IHANDLE_VALID(i)	((i) != 0 && (i) != PROM_ERROR)
+
+
+/* This is the one and *ONLY* place where we actually call open
+ * firmware.
+ */
+
+static int __init call_prom(const char *service, int nargs, int nret, ...)
+{
+	int i;
+	struct prom_args args;
+	va_list list;
+
+	args.service = ADDR(service);
+	args.nargs = nargs;
+	args.nret = nret;
+
+	va_start(list, nret);
+	for (i = 0; i < nargs; i++)
+		args.args[i] = va_arg(list, prom_arg_t);
+	va_end(list);
+
+	for (i = 0; i < nret; i++)
+		args.args[nargs+i] = 0;
+
+	enter_prom(&args, RELOC(prom_entry));
+
+	return (nret > 0) ? args.args[nargs] : 0;
+}
+
+static int __init call_prom_ret(const char *service, int nargs, int nret,
+				prom_arg_t *rets, ...)
+{
+	int i;
+	struct prom_args args;
+	va_list list;
+
+	args.service = ADDR(service);
+	args.nargs = nargs;
+	args.nret = nret;
+
+	va_start(list, rets);
+	for (i = 0; i < nargs; i++)
+		args.args[i] = va_arg(list, prom_arg_t);
+	va_end(list);
+
+	for (i = 0; i < nret; i++)
+		rets[nargs+i] = 0;
+
+	enter_prom(&args, RELOC(prom_entry));
+
+	if (rets != NULL)
+		for (i = 1; i < nret; ++i)
+			rets[i] = args.args[nargs+i];
+
+	return (nret > 0) ? args.args[nargs] : 0;
+}
+
+
+static unsigned int __init prom_claim(unsigned long virt, unsigned long size,
+				unsigned long align)
+{
+	return (unsigned int)call_prom("claim", 3, 1,
+				       (prom_arg_t)virt, (prom_arg_t)size,
+				       (prom_arg_t)align);
+}
+
+static void __init prom_print(const char *msg)
+{
+	const char *p, *q;
+	struct prom_t *_prom = &RELOC(prom);
+
+	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)
+			break;
+		++q;
+		call_prom("write", 3, 1, _prom->stdout, ADDR("\r\n"), 2);
+	}
+}
+
+
+static void __init prom_print_hex(unsigned long val)
+{
+	int i, nibbles = sizeof(val)*2;
+	char buf[sizeof(val)*2+1];
+	struct prom_t *_prom = &RELOC(prom);
+
+	for (i = nibbles-1;  i >= 0;  i--) {
+		buf[i] = (val & 0xf) + '0';
+		if (buf[i] > '9')
+			buf[i] += ('a'-'0'-10);
+		val >>= 4;
+	}
+	buf[nibbles] = '\0';
+	call_prom("write", 3, 1, _prom->stdout, buf, nibbles);
+}
+
+
+static void __init prom_printf(const char *format, ...)
+{
+	const char *p, *q, *s;
+	va_list args;
+	unsigned long v;
+	struct prom_t *_prom = &RELOC(prom);
+
+	va_start(args, format);
+#ifdef CONFIG_PPC64
+	format = PTRRELOC(format);
+#endif
+	for (p = format; *p != 0; p = q) {
+		for (q = p; *q != 0 && *q != '\n' && *q != '%'; ++q)
+			;
+		if (q > p)
+			call_prom("write", 3, 1, _prom->stdout, p, q - p);
+		if (*q == 0)
+			break;
+		if (*q == '\n') {
+			++q;
+			call_prom("write", 3, 1, _prom->stdout,
+				  ADDR("\r\n"), 2);
+			continue;
+		}
+		++q;
+		if (*q == 0)
+			break;
+		switch (*q) {
+		case 's':
+			++q;
+			s = va_arg(args, const char *);
+			prom_print(s);
+			break;
+		case 'x':
+			++q;
+			v = va_arg(args, unsigned long);
+			prom_print_hex(v);
+			break;
+		}
+	}
+}
+
+
+static void __init __attribute__((noreturn)) prom_panic(const char *reason)
+{
+#ifdef CONFIG_PPC64
+	reason = PTRRELOC(reason);
+#endif
+	prom_print(reason);
+	/* ToDo: should put up an SRC here on p/iSeries */
+	call_prom("exit", 0, 0);
+
+	for (;;)			/* should never get here */
+		;
+}
+
+
+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;
+	}
+}
+
+static int __init prom_getprop(phandle node, const char *pname,
+			       void *value, size_t valuelen)
+{
+	return call_prom("getprop", 4, 1, node, ADDR(pname),
+			 (u32)(unsigned long) value, (u32) valuelen);
+}
+
+static int __init prom_getproplen(phandle node, const char *pname)
+{
+	return call_prom("getproplen", 2, 1, node, ADDR(pname));
+}
+
+static int __init prom_setprop(phandle node, const char *pname,
+			       void *value, size_t valuelen)
+{
+	return call_prom("setprop", 4, 1, node, ADDR(pname),
+			 (u32)(unsigned long) value, (u32) valuelen);
+}
+
+/* We can't use the standard versions because of RELOC headaches. */
+#define isxdigit(c)	(('0' <= (c) && (c) <= '9') \
+			 || ('a' <= (c) && (c) <= 'f') \
+			 || ('A' <= (c) && (c) <= 'F'))
+
+#define isdigit(c)	('0' <= (c) && (c) <= '9')
+#define islower(c)	('a' <= (c) && (c) <= 'z')
+#define toupper(c)	(islower(c) ? ((c) - 'a' + 'A') : (c))
+
+unsigned long prom_strtoul(const char *cp, const char **endp)
+{
+	unsigned long result = 0, base = 10, value;
+
+	if (*cp == '0') {
+		base = 8;
+		cp++;
+		if (toupper(*cp) == 'X') {
+			cp++;
+			base = 16;
+		}
+	}
+
+	while (isxdigit(*cp) &&
+	       (value = isdigit(*cp) ? *cp - '0' : toupper(*cp) - 'A' + 10) < base) {
+		result = result * base + value;
+		cp++;
+	}
+
+	if (endp)
+		*endp = cp;
+
+	return result;
+}
+
+unsigned long prom_memparse(const char *ptr, const char **retptr)
+{
+	unsigned long ret = prom_strtoul(ptr, retptr);
+	int shift = 0;
+
+	/*
+	 * We can't use a switch here because GCC *may* generate a
+	 * jump table which won't work, because we're not running at
+	 * the address we're linked at.
+	 */
+	if ('G' == **retptr || 'g' == **retptr)
+		shift = 30;
+
+	if ('M' == **retptr || 'm' == **retptr)
+		shift = 20;
+
+	if ('K' == **retptr || 'k' == **retptr)
+		shift = 10;
+
+	if (shift) {
+		ret <<= shift;
+		(*retptr)++;
+	}
+
+	return ret;
+}
+
+/*
+ * Early parsing of the command line passed to the kernel, used for
+ * "mem=x" and the options that affect the iommu
+ */
+static void __init early_cmdline_parse(void)
+{
+	struct prom_t *_prom = &RELOC(prom);
+	char *opt, *p;
+	int l = 0;
+
+	RELOC(prom_cmd_line[0]) = 0;
+	p = RELOC(prom_cmd_line);
+	if ((long)_prom->chosen > 0)
+		l = prom_getprop(_prom->chosen, "bootargs", p, COMMAND_LINE_SIZE-1);
+#ifdef CONFIG_CMDLINE
+	if (l == 0) /* dbl check */
+		strlcpy(RELOC(prom_cmd_line),
+			RELOC(CONFIG_CMDLINE), sizeof(prom_cmd_line));
+#endif /* CONFIG_CMDLINE */
+	prom_printf("command line: %s\n", RELOC(prom_cmd_line));
+
+#ifdef CONFIG_PPC64
+	opt = strstr(RELOC(prom_cmd_line), RELOC("iommu="));
+	if (opt) {
+		prom_printf("iommu opt is: %s\n", opt);
+		opt += 6;
+		while (*opt && *opt == ' ')
+			opt++;
+		if (!strncmp(opt, RELOC("off"), 3))
+			RELOC(ppc64_iommu_off) = 1;
+		else if (!strncmp(opt, RELOC("force"), 5))
+			RELOC(iommu_force_on) = 1;
+	}
+#endif
+
+	opt = strstr(RELOC(prom_cmd_line), RELOC("mem="));
+	if (opt) {
+		opt += 4;
+		RELOC(prom_memory_limit) = prom_memparse(opt, (const char **)&opt);
+#ifdef CONFIG_PPC64
+		/* Align to 16 MB == size of ppc64 large page */
+		RELOC(prom_memory_limit) = ALIGN(RELOC(prom_memory_limit), 0x1000000);
+#endif
+	}
+}
+
+#ifdef CONFIG_PPC_PSERIES
+/*
+ * To tell the firmware what our capabilities are, we have to pass
+ * it a fake 32-bit ELF header containing a couple of PT_NOTE sections
+ * that contain structures that contain the actual values.
+ */
+static struct fake_elf {
+	Elf32_Ehdr	elfhdr;
+	Elf32_Phdr	phdr[2];
+	struct chrpnote {
+		u32	namesz;
+		u32	descsz;
+		u32	type;
+		char	name[8];	/* "PowerPC" */
+		struct chrpdesc {
+			u32	real_mode;
+			u32	real_base;
+			u32	real_size;
+			u32	virt_base;
+			u32	virt_size;
+			u32	load_base;
+		} chrpdesc;
+	} chrpnote;
+	struct rpanote {
+		u32	namesz;
+		u32	descsz;
+		u32	type;
+		char	name[24];	/* "IBM,RPA-Client-Config" */
+		struct rpadesc {
+			u32	lpar_affinity;
+			u32	min_rmo_size;
+			u32	min_rmo_percent;
+			u32	max_pft_size;
+			u32	splpar;
+			u32	min_load;
+			u32	new_mem_def;
+			u32	ignore_me;
+		} rpadesc;
+	} rpanote;
+} fake_elf = {
+	.elfhdr = {
+		.e_ident = { 0x7f, 'E', 'L', 'F',
+			     ELFCLASS32, ELFDATA2MSB, EV_CURRENT },
+		.e_type = ET_EXEC,	/* yeah right */
+		.e_machine = EM_PPC,
+		.e_version = EV_CURRENT,
+		.e_phoff = offsetof(struct fake_elf, phdr),
+		.e_phentsize = sizeof(Elf32_Phdr),
+		.e_phnum = 2
+	},
+	.phdr = {
+		[0] = {
+			.p_type = PT_NOTE,
+			.p_offset = offsetof(struct fake_elf, chrpnote),
+			.p_filesz = sizeof(struct chrpnote)
+		}, [1] = {
+			.p_type = PT_NOTE,
+			.p_offset = offsetof(struct fake_elf, rpanote),
+			.p_filesz = sizeof(struct rpanote)
+		}
+	},
+	.chrpnote = {
+		.namesz = sizeof("PowerPC"),
+		.descsz = sizeof(struct chrpdesc),
+		.type = 0x1275,
+		.name = "PowerPC",
+		.chrpdesc = {
+			.real_mode = ~0U,	/* ~0 means "don't care" */
+			.real_base = ~0U,
+			.real_size = ~0U,
+			.virt_base = ~0U,
+			.virt_size = ~0U,
+			.load_base = ~0U
+		},
+	},
+	.rpanote = {
+		.namesz = sizeof("IBM,RPA-Client-Config"),
+		.descsz = sizeof(struct rpadesc),
+		.type = 0x12759999,
+		.name = "IBM,RPA-Client-Config",
+		.rpadesc = {
+			.lpar_affinity = 0,
+			.min_rmo_size = 64,	/* in megabytes */
+			.min_rmo_percent = 0,
+			.max_pft_size = 48,	/* 2^48 bytes max PFT size */
+			.splpar = 1,
+			.min_load = ~0U,
+			.new_mem_def = 0
+		}
+	}
+};
+
+static void __init prom_send_capabilities(void)
+{
+	ihandle elfloader;
+
+	elfloader = call_prom("open", 1, 1, ADDR("/packages/elf-loader"));
+	if (elfloader == 0) {
+		prom_printf("couldn't open /packages/elf-loader\n");
+		return;
+	}
+	call_prom("call-method", 3, 1, ADDR("process-elf-header"),
+			elfloader, ADDR(&fake_elf));
+	call_prom("close", 1, 0, elfloader);
+}
+#endif
+
+/*
+ * Memory allocation strategy... our layout is normally:
+ *
+ *  at 14Mb or more we have vmlinux, then a gap and initrd.  In some
+ *  rare cases, initrd might end up being before the kernel though.
+ *  We assume this won't override the final kernel at 0, we have no
+ *  provision to handle that in this version, but it should hopefully
+ *  never happen.
+ *
+ *  alloc_top is set to the top of RMO, eventually shrink down if the
+ *  TCEs overlap
+ *
+ *  alloc_bottom is set to the top of kernel/initrd
+ *
+ *  from there, allocations are done this way : rtas is allocated
+ *  topmost, and the device-tree is allocated from the bottom. We try
+ *  to grow the device-tree allocation as we progress. If we can't,
+ *  then we fail, we don't currently have a facility to restart
+ *  elsewhere, but that shouldn't be necessary.
+ *
+ *  Note that calls to reserve_mem have to be done explicitly, memory
+ *  allocated with either alloc_up or alloc_down isn't automatically
+ *  reserved.
+ */
+
+
+/*
+ * Allocates memory in the RMO upward from the kernel/initrd
+ *
+ * When align is 0, this is a special case, it means to allocate in place
+ * at the current location of alloc_bottom or fail (that is basically
+ * extending the previous allocation). Used for the device-tree flattening
+ */
+static unsigned long __init alloc_up(unsigned long size, unsigned long align)
+{
+	unsigned long base = _ALIGN_UP(RELOC(alloc_bottom), align);
+	unsigned long addr = 0;
+
+	prom_debug("alloc_up(%x, %x)\n", size, align);
+	if (RELOC(ram_top) == 0)
+		prom_panic("alloc_up() called with mem not initialized\n");
+
+	if (align)
+		base = _ALIGN_UP(RELOC(alloc_bottom), align);
+	else
+		base = RELOC(alloc_bottom);
+
+	for(; (base + size) <= RELOC(alloc_top); 
+	    base = _ALIGN_UP(base + 0x100000, align)) {
+		prom_debug("    trying: 0x%x\n\r", base);
+		addr = (unsigned long)prom_claim(base, size, 0);
+		if (addr != PROM_ERROR)
+			break;
+		addr = 0;
+		if (align == 0)
+			break;
+	}
+	if (addr == 0)
+		return 0;
+	RELOC(alloc_bottom) = addr;
+
+	prom_debug(" -> %x\n", addr);
+	prom_debug("  alloc_bottom : %x\n", RELOC(alloc_bottom));
+	prom_debug("  alloc_top    : %x\n", RELOC(alloc_top));
+	prom_debug("  alloc_top_hi : %x\n", RELOC(alloc_top_high));
+	prom_debug("  rmo_top      : %x\n", RELOC(rmo_top));
+	prom_debug("  ram_top      : %x\n", RELOC(ram_top));
+
+	return addr;
+}
+
+/*
+ * Allocates memory downward, either from top of RMO, or if highmem
+ * is set, from the top of RAM.  Note that this one doesn't handle
+ * failures.  It does claim memory if highmem is not set.
+ */
+static unsigned long __init alloc_down(unsigned long size, unsigned long align,
+				       int highmem)
+{
+	unsigned long base, addr = 0;
+
+	prom_debug("alloc_down(%x, %x, %s)\n", size, align,
+		   highmem ? RELOC("(high)") : RELOC("(low)"));
+	if (RELOC(ram_top) == 0)
+		prom_panic("alloc_down() called with mem not initialized\n");
+
+	if (highmem) {
+		/* Carve out storage for the TCE table. */
+		addr = _ALIGN_DOWN(RELOC(alloc_top_high) - size, align);
+		if (addr <= RELOC(alloc_bottom))
+			return 0;
+		/* Will we bump into the RMO ? If yes, check out that we
+		 * didn't overlap existing allocations there, if we did,
+		 * we are dead, we must be the first in town !
+		 */
+		if (addr < RELOC(rmo_top)) {
+			/* Good, we are first */
+			if (RELOC(alloc_top) == RELOC(rmo_top))
+				RELOC(alloc_top) = RELOC(rmo_top) = addr;
+			else
+				return 0;
+		}
+		RELOC(alloc_top_high) = addr;
+		goto bail;
+	}
+
+	base = _ALIGN_DOWN(RELOC(alloc_top) - size, align);
+	for (; base > RELOC(alloc_bottom);
+	     base = _ALIGN_DOWN(base - 0x100000, align))  {
+		prom_debug("    trying: 0x%x\n\r", base);
+		addr = (unsigned long)prom_claim(base, size, 0);
+		if (addr != PROM_ERROR)
+			break;
+		addr = 0;
+	}
+	if (addr == 0)
+		return 0;
+	RELOC(alloc_top) = addr;
+
+ bail:
+	prom_debug(" -> %x\n", addr);
+	prom_debug("  alloc_bottom : %x\n", RELOC(alloc_bottom));
+	prom_debug("  alloc_top    : %x\n", RELOC(alloc_top));
+	prom_debug("  alloc_top_hi : %x\n", RELOC(alloc_top_high));
+	prom_debug("  rmo_top      : %x\n", RELOC(rmo_top));
+	prom_debug("  ram_top      : %x\n", RELOC(ram_top));
+
+	return addr;
+}
+
+/*
+ * Parse a "reg" cell
+ */
+static unsigned long __init prom_next_cell(int s, cell_t **cellp)
+{
+	cell_t *p = *cellp;
+	unsigned long r = 0;
+
+	/* Ignore more than 2 cells */
+	while (s > sizeof(unsigned long) / 4) {
+		p++;
+		s--;
+	}
+	r = *p++;
+#ifdef CONFIG_PPC64
+	if (s) {
+		r <<= 32;
+		r |= *(p++);
+	}
+#endif
+	*cellp = p;
+	return r;
+}
+
+/*
+ * Very dumb function for adding to the memory reserve list, but
+ * we don't need anything smarter at this point
+ *
+ * XXX Eventually check for collisions.  They should NEVER happen.
+ * If problems seem to show up, it would be a good start to track
+ * them down.
+ */
+static void reserve_mem(unsigned long base, unsigned long size)
+{
+	unsigned long top = base + size;
+	unsigned long cnt = RELOC(mem_reserve_cnt);
+
+	if (size == 0)
+		return;
+
+	/* We need to always keep one empty entry so that we
+	 * have our terminator with "size" set to 0 since we are
+	 * dumb and just copy this entire array to the boot params
+	 */
+	base = _ALIGN_DOWN(base, PAGE_SIZE);
+	top = _ALIGN_UP(top, PAGE_SIZE);
+	size = top - base;
+
+	if (cnt >= (MEM_RESERVE_MAP_SIZE - 1))
+		prom_panic("Memory reserve map exhausted !\n");
+	RELOC(mem_reserve_map)[cnt].base = base;
+	RELOC(mem_reserve_map)[cnt].size = size;
+	RELOC(mem_reserve_cnt) = cnt + 1;
+}
+
+/*
+ * Initialize memory allocation mecanism, parse "memory" nodes and
+ * obtain that way the top of memory and RMO to setup out local allocator
+ */
+static void __init prom_init_mem(void)
+{
+	phandle node;
+	char *path, type[64];
+	unsigned int plen;
+	cell_t *p, *endp;
+	struct prom_t *_prom = &RELOC(prom);
+	u32 rac, rsc;
+
+	/*
+	 * We iterate the memory nodes to find
+	 * 1) top of RMO (first node)
+	 * 2) top of memory
+	 */
+	rac = 2;
+	prom_getprop(_prom->root, "#address-cells", &rac, sizeof(rac));
+	rsc = 1;
+	prom_getprop(_prom->root, "#size-cells", &rsc, sizeof(rsc));
+	prom_debug("root_addr_cells: %x\n", (unsigned long) rac);
+	prom_debug("root_size_cells: %x\n", (unsigned long) rsc);
+
+	prom_debug("scanning memory:\n");
+	path = RELOC(prom_scratch);
+
+	for (node = 0; prom_next_node(&node); ) {
+		type[0] = 0;
+		prom_getprop(node, "device_type", type, sizeof(type));
+
+		if (strcmp(type, RELOC("memory")))
+			continue;
+	
+		plen = prom_getprop(node, "reg", RELOC(regbuf), sizeof(regbuf));
+		if (plen > sizeof(regbuf)) {
+			prom_printf("memory node too large for buffer !\n");
+			plen = sizeof(regbuf);
+		}
+		p = RELOC(regbuf);
+		endp = p + (plen / sizeof(cell_t));
+
+#ifdef DEBUG_PROM
+		memset(path, 0, PROM_SCRATCH_SIZE);
+		call_prom("package-to-path", 3, 1, node, path, PROM_SCRATCH_SIZE-1);
+		prom_debug("  node %s :\n", path);
+#endif /* DEBUG_PROM */
+
+		while ((endp - p) >= (rac + rsc)) {
+			unsigned long base, size;
+
+			base = prom_next_cell(rac, &p);
+			size = prom_next_cell(rsc, &p);
+
+			if (size == 0)
+				continue;
+			prom_debug("    %x %x\n", base, size);
+			if (base == 0)
+				RELOC(rmo_top) = size;
+			if ((base + size) > RELOC(ram_top))
+				RELOC(ram_top) = base + size;
+		}
+	}
+
+	RELOC(alloc_bottom) = PAGE_ALIGN((unsigned long)&RELOC(_end) + 0x4000);
+
+	/* Check if we have an initrd after the kernel, if we do move our bottom
+	 * point to after it
+	 */
+	if (RELOC(prom_initrd_start)) {
+		if (RELOC(prom_initrd_end) > RELOC(alloc_bottom))
+			RELOC(alloc_bottom) = PAGE_ALIGN(RELOC(prom_initrd_end));
+	}
+
+	/*
+	 * If prom_memory_limit is set we reduce the upper limits *except* for
+	 * alloc_top_high. This must be the real top of RAM so we can put
+	 * TCE's up there.
+	 */
+
+	RELOC(alloc_top_high) = RELOC(ram_top);
+
+	if (RELOC(prom_memory_limit)) {
+		if (RELOC(prom_memory_limit) <= RELOC(alloc_bottom)) {
+			prom_printf("Ignoring mem=%x <= alloc_bottom.\n",
+				RELOC(prom_memory_limit));
+			RELOC(prom_memory_limit) = 0;
+		} else if (RELOC(prom_memory_limit) >= RELOC(ram_top)) {
+			prom_printf("Ignoring mem=%x >= ram_top.\n",
+				RELOC(prom_memory_limit));
+			RELOC(prom_memory_limit) = 0;
+		} else {
+			RELOC(ram_top) = RELOC(prom_memory_limit);
+			RELOC(rmo_top) = min(RELOC(rmo_top), RELOC(prom_memory_limit));
+		}
+	}
+
+	/*
+	 * Setup our top alloc point, that is top of RMO or top of
+	 * segment 0 when running non-LPAR.
+	 * Some RS64 machines have buggy firmware where claims up at
+	 * 1GB fail.  Cap at 768MB as a workaround.
+	 * Since 768MB is plenty of room, and we need to cap to something
+	 * reasonable on 32-bit, cap at 768MB on all machines.
+	 */
+	if (!RELOC(rmo_top))
+		RELOC(rmo_top) = RELOC(ram_top);
+	RELOC(rmo_top) = min(0x30000000ul, RELOC(rmo_top));
+	RELOC(alloc_top) = RELOC(rmo_top);
+
+	prom_printf("memory layout at init:\n");
+	prom_printf("  memory_limit : %x (16 MB aligned)\n", RELOC(prom_memory_limit));
+	prom_printf("  alloc_bottom : %x\n", RELOC(alloc_bottom));
+	prom_printf("  alloc_top    : %x\n", RELOC(alloc_top));
+	prom_printf("  alloc_top_hi : %x\n", RELOC(alloc_top_high));
+	prom_printf("  rmo_top      : %x\n", RELOC(rmo_top));
+	prom_printf("  ram_top      : %x\n", RELOC(ram_top));
+}
+
+
+/*
+ * Allocate room for and instantiate RTAS
+ */
+static void __init prom_instantiate_rtas(void)
+{
+	phandle rtas_node;
+	ihandle rtas_inst;
+	u32 base, entry = 0;
+	u32 size = 0;
+
+	prom_debug("prom_instantiate_rtas: start...\n");
+
+	rtas_node = call_prom("finddevice", 1, 1, ADDR("/rtas"));
+	prom_debug("rtas_node: %x\n", rtas_node);
+	if (!PHANDLE_VALID(rtas_node))
+		return;
+
+	prom_getprop(rtas_node, "rtas-size", &size, sizeof(size));
+	if (size == 0)
+		return;
+
+	base = alloc_down(size, PAGE_SIZE, 0);
+	if (base == 0) {
+		prom_printf("RTAS allocation failed !\n");
+		return;
+	}
+
+	rtas_inst = call_prom("open", 1, 1, ADDR("/rtas"));
+	if (!IHANDLE_VALID(rtas_inst)) {
+		prom_printf("opening rtas package failed");
+		return;
+	}
+
+	prom_printf("instantiating rtas at 0x%x ...", base);
+
+	if (call_prom_ret("call-method", 3, 2, &entry,
+			  ADDR("instantiate-rtas"),
+			  rtas_inst, base) == PROM_ERROR
+	    || entry == 0) {
+		prom_printf(" failed\n");
+		return;
+	}
+	prom_printf(" done\n");
+
+	reserve_mem(base, size);
+
+	prom_setprop(rtas_node, "linux,rtas-base", &base, sizeof(base));
+	prom_setprop(rtas_node, "linux,rtas-entry", &entry, sizeof(entry));
+
+	prom_debug("rtas base     = 0x%x\n", base);
+	prom_debug("rtas entry    = 0x%x\n", entry);
+	prom_debug("rtas size     = 0x%x\n", (long)size);
+
+	prom_debug("prom_instantiate_rtas: end...\n");
+}
+
+#ifdef CONFIG_PPC64
+/*
+ * Allocate room for and initialize TCE tables
+ */
+static void __init prom_initialize_tce_table(void)
+{
+	phandle node;
+	ihandle phb_node;
+	char compatible[64], type[64], model[64];
+	char *path = RELOC(prom_scratch);
+	u64 base, align;
+	u32 minalign, minsize;
+	u64 tce_entry, *tce_entryp;
+	u64 local_alloc_top, local_alloc_bottom;
+	u64 i;
+
+	if (RELOC(ppc64_iommu_off))
+		return;
+
+	prom_debug("starting prom_initialize_tce_table\n");
+
+	/* Cache current top of allocs so we reserve a single block */
+	local_alloc_top = RELOC(alloc_top_high);
+	local_alloc_bottom = local_alloc_top;
+
+	/* Search all nodes looking for PHBs. */
+	for (node = 0; prom_next_node(&node); ) {
+		compatible[0] = 0;
+		type[0] = 0;
+		model[0] = 0;
+		prom_getprop(node, "compatible",
+			     compatible, sizeof(compatible));
+		prom_getprop(node, "device_type", type, sizeof(type));
+		prom_getprop(node, "model", model, sizeof(model));
+
+		if ((type[0] == 0) || (strstr(type, RELOC("pci")) == NULL))
+			continue;
+
+		/* Keep the old logic in tack to avoid regression. */
+		if (compatible[0] != 0) {
+			if ((strstr(compatible, RELOC("python")) == NULL) &&
+			    (strstr(compatible, RELOC("Speedwagon")) == NULL) &&
+			    (strstr(compatible, RELOC("Winnipeg")) == NULL))
+				continue;
+		} else if (model[0] != 0) {
+			if ((strstr(model, RELOC("ython")) == NULL) &&
+			    (strstr(model, RELOC("peedwagon")) == NULL) &&
+			    (strstr(model, RELOC("innipeg")) == NULL))
+				continue;
+		}
+
+		if (prom_getprop(node, "tce-table-minalign", &minalign,
+				 sizeof(minalign)) == PROM_ERROR)
+			minalign = 0;
+		if (prom_getprop(node, "tce-table-minsize", &minsize,
+				 sizeof(minsize)) == PROM_ERROR)
+			minsize = 4UL << 20;
+
+		/*
+		 * Even though we read what OF wants, we just set the table
+		 * size to 4 MB.  This is enough to map 2GB of PCI DMA space.
+		 * By doing this, we avoid the pitfalls of trying to DMA to
+		 * MMIO space and the DMA alias hole.
+		 *
+		 * On POWER4, firmware sets the TCE region by assuming
+		 * each TCE table is 8MB. Using this memory for anything
+		 * else will impact performance, so we always allocate 8MB.
+		 * Anton
+		 */
+		if (__is_processor(PV_POWER4) || __is_processor(PV_POWER4p))
+			minsize = 8UL << 20;
+		else
+			minsize = 4UL << 20;
+
+		/* Align to the greater of the align or size */
+		align = max(minalign, minsize);
+		base = alloc_down(minsize, align, 1);
+		if (base == 0)
+			prom_panic("ERROR, cannot find space for TCE table.\n");
+		if (base < local_alloc_bottom)
+			local_alloc_bottom = base;
+
+		/* Save away the TCE table attributes for later use. */
+		prom_setprop(node, "linux,tce-base", &base, sizeof(base));
+		prom_setprop(node, "linux,tce-size", &minsize, sizeof(minsize));
+
+		/* It seems OF doesn't null-terminate the path :-( */
+		memset(path, 0, sizeof(path));
+		/* Call OF to setup the TCE hardware */
+		if (call_prom("package-to-path", 3, 1, node,
+			      path, PROM_SCRATCH_SIZE-1) == PROM_ERROR) {
+			prom_printf("package-to-path failed\n");
+		}
+
+		prom_debug("TCE table: %s\n", path);
+		prom_debug("\tnode = 0x%x\n", node);
+		prom_debug("\tbase = 0x%x\n", base);
+		prom_debug("\tsize = 0x%x\n", minsize);
+
+		/* Initialize the table to have a one-to-one mapping
+		 * over the allocated size.
+		 */
+		tce_entryp = (unsigned long *)base;
+		for (i = 0; i < (minsize >> 3) ;tce_entryp++, i++) {
+			tce_entry = (i << PAGE_SHIFT);
+			tce_entry |= 0x3;
+			*tce_entryp = tce_entry;
+		}
+
+		prom_printf("opening PHB %s", path);
+		phb_node = call_prom("open", 1, 1, path);
+		if (phb_node == 0)
+			prom_printf("... failed\n");
+		else
+			prom_printf("... done\n");
+
+		call_prom("call-method", 6, 0, ADDR("set-64-bit-addressing"),
+			  phb_node, -1, minsize,
+			  (u32) base, (u32) (base >> 32));
+		call_prom("close", 1, 0, phb_node);
+	}
+
+	reserve_mem(local_alloc_bottom, local_alloc_top - local_alloc_bottom);
+
+	if (RELOC(prom_memory_limit)) {
+		/*
+		 * We align the start to a 16MB boundary so we can map
+		 * the TCE area using large pages if possible.
+		 * The end should be the top of RAM so no need to align it.
+		 */
+		RELOC(prom_tce_alloc_start) = _ALIGN_DOWN(local_alloc_bottom,
+							  0x1000000);
+		RELOC(prom_tce_alloc_end) = local_alloc_top;
+	}
+
+	/* Flag the first invalid entry */
+	prom_debug("ending prom_initialize_tce_table\n");
+}
+#endif
+
+/*
+ * With CHRP SMP we need to use the OF to start the other processors.
+ * 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 low memory, puts some holding pattern
+ * code there and sends the other processors off to there until
+ * smp_boot_cpus tells them to do something.  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
+ */
+static void __init prom_hold_cpus(void)
+{
+#ifdef CONFIG_PPC64
+	unsigned long i;
+	unsigned int reg;
+	phandle node;
+	char type[64];
+	int cpuid = 0;
+	unsigned int interrupt_server[MAX_CPU_THREADS];
+	unsigned int cpu_threads, hw_cpu_num;
+	int propsize;
+	extern void __secondary_hold(void);
+	extern unsigned long __secondary_hold_spinloop;
+	extern unsigned long __secondary_hold_acknowledge;
+	unsigned long *spinloop
+		= (void *) __pa(&__secondary_hold_spinloop);
+	unsigned long *acknowledge
+		= (void *) __pa(&__secondary_hold_acknowledge);
+#ifdef CONFIG_PPC64
+	unsigned long secondary_hold
+		= __pa(*PTRRELOC((unsigned long *)__secondary_hold));
+#else
+	unsigned long secondary_hold = __pa(&__secondary_hold);
+#endif
+	struct prom_t *_prom = &RELOC(prom);
+
+	prom_debug("prom_hold_cpus: start...\n");
+	prom_debug("    1) spinloop       = 0x%x\n", (unsigned long)spinloop);
+	prom_debug("    1) *spinloop      = 0x%x\n", *spinloop);
+	prom_debug("    1) acknowledge    = 0x%x\n",
+		   (unsigned long)acknowledge);
+	prom_debug("    1) *acknowledge   = 0x%x\n", *acknowledge);
+	prom_debug("    1) secondary_hold = 0x%x\n", secondary_hold);
+
+	/* Set the common spinloop variable, so all of the secondary cpus
+	 * will block when they are awakened from their OF spinloop.
+	 * This must occur for both SMP and non SMP kernels, since OF will
+	 * be trashed when we move the kernel.
+	 */
+	*spinloop = 0;
+
+#ifdef CONFIG_HMT
+	for (i = 0; i < NR_CPUS; i++) {
+		RELOC(hmt_thread_data)[i].pir = 0xdeadbeef;
+	}
+#endif
+	/* look for cpus */
+	for (node = 0; prom_next_node(&node); ) {
+		type[0] = 0;
+		prom_getprop(node, "device_type", type, sizeof(type));
+		if (strcmp(type, RELOC("cpu")) != 0)
+			continue;
+
+		/* Skip non-configured cpus. */
+		if (prom_getprop(node, "status", type, sizeof(type)) > 0)
+			if (strcmp(type, RELOC("okay")) != 0)
+				continue;
+
+		reg = -1;
+		prom_getprop(node, "reg", &reg, sizeof(reg));
+
+		prom_debug("\ncpuid        = 0x%x\n", cpuid);
+		prom_debug("cpu hw idx   = 0x%x\n", reg);
+
+		/* Init the acknowledge var which will be reset by
+		 * the secondary cpu when it awakens from its OF
+		 * spinloop.
+		 */
+		*acknowledge = (unsigned long)-1;
+
+		propsize = prom_getprop(node, "ibm,ppc-interrupt-server#s",
+					&interrupt_server,
+					sizeof(interrupt_server));
+		if (propsize < 0) {
+			/* no property.  old hardware has no SMT */
+			cpu_threads = 1;
+			interrupt_server[0] = reg; /* fake it with phys id */
+		} else {
+			/* We have a threaded processor */
+			cpu_threads = propsize / sizeof(u32);
+			if (cpu_threads > MAX_CPU_THREADS) {
+				prom_printf("SMT: too many threads!\n"
+					    "SMT: found %x, max is %x\n",
+					    cpu_threads, MAX_CPU_THREADS);
+				cpu_threads = 1; /* ToDo: panic? */
+			}
+		}
+
+		hw_cpu_num = interrupt_server[0];
+		if (hw_cpu_num != _prom->cpu) {
+			/* Primary Thread of non-boot cpu */
+			prom_printf("%x : starting cpu hw idx %x... ", cpuid, reg);
+			call_prom("start-cpu", 3, 0, node,
+				  secondary_hold, reg);
+
+			for ( i = 0 ; (i < 100000000) && 
+			      (*acknowledge == ((unsigned long)-1)); i++ )
+				mb();
+
+			if (*acknowledge == reg) {
+				prom_printf("done\n");
+				/* We have to get every CPU out of OF,
+				 * even if we never start it. */
+				if (cpuid >= NR_CPUS)
+					goto next;
+			} else {
+				prom_printf("failed: %x\n", *acknowledge);
+			}
+		}
+#ifdef CONFIG_SMP
+		else
+			prom_printf("%x : boot cpu     %x\n", cpuid, reg);
+#endif
+next:
+#ifdef CONFIG_SMP
+		/* Init paca for secondary threads.   They start later. */
+		for (i=1; i < cpu_threads; i++) {
+			cpuid++;
+			if (cpuid >= NR_CPUS)
+				continue;
+		}
+#endif /* CONFIG_SMP */
+		cpuid++;
+	}
+#ifdef CONFIG_HMT
+	/* Only enable HMT on processors that provide support. */
+	if (__is_processor(PV_PULSAR) || 
+	    __is_processor(PV_ICESTAR) ||
+	    __is_processor(PV_SSTAR)) {
+		prom_printf("    starting secondary threads\n");
+
+		for (i = 0; i < NR_CPUS; i += 2) {
+			if (!cpu_online(i))
+				continue;
+
+			if (i == 0) {
+				unsigned long pir = mfspr(SPRN_PIR);
+				if (__is_processor(PV_PULSAR)) {
+					RELOC(hmt_thread_data)[i].pir = 
+						pir & 0x1f;
+				} else {
+					RELOC(hmt_thread_data)[i].pir = 
+						pir & 0x3ff;
+				}
+			}
+		}
+	} else {
+		prom_printf("Processor is not HMT capable\n");
+	}
+#endif
+
+	if (cpuid > NR_CPUS)
+		prom_printf("WARNING: maximum CPUs (" __stringify(NR_CPUS)
+			    ") exceeded: ignoring extras\n");
+
+	prom_debug("prom_hold_cpus: end...\n");
+#endif
+}
+
+
+static void __init prom_init_client_services(unsigned long pp)
+{
+	struct prom_t *_prom = &RELOC(prom);
+
+	/* Get a handle to the prom entry point before anything else */
+	RELOC(prom_entry) = pp;
+
+	/* get a handle for the stdout device */
+	_prom->chosen = call_prom("finddevice", 1, 1, ADDR("/chosen"));
+	if (!PHANDLE_VALID(_prom->chosen))
+		prom_panic("cannot find chosen"); /* msg won't be printed :( */
+
+	/* get device tree root */
+	_prom->root = call_prom("finddevice", 1, 1, ADDR("/"));
+	if (!PHANDLE_VALID(_prom->root))
+		prom_panic("cannot find device tree root"); /* msg won't be printed :( */
+}
+
+static void __init prom_init_stdout(void)
+{
+	struct prom_t *_prom = &RELOC(prom);
+	char *path = RELOC(of_stdout_device);
+	char type[16];
+	u32 val;
+
+	if (prom_getprop(_prom->chosen, "stdout", &val, sizeof(val)) <= 0)
+		prom_panic("cannot find stdout");
+
+	_prom->stdout = val;
+
+	/* Get the full OF pathname of the stdout device */
+	memset(path, 0, 256);
+	call_prom("instance-to-path", 3, 1, _prom->stdout, path, 255);
+	val = call_prom("instance-to-package", 1, 1, _prom->stdout);
+	prom_setprop(_prom->chosen, "linux,stdout-package", &val, sizeof(val));
+	prom_printf("OF stdout device is: %s\n", RELOC(of_stdout_device));
+	prom_setprop(_prom->chosen, "linux,stdout-path",
+		     RELOC(of_stdout_device), strlen(RELOC(of_stdout_device))+1);
+
+	/* If it's a display, note it */
+	memset(type, 0, sizeof(type));
+	prom_getprop(val, "device_type", type, sizeof(type));
+	if (strcmp(type, RELOC("display")) == 0)
+		prom_setprop(val, "linux,boot-display", NULL, 0);
+}
+
+static void __init prom_close_stdin(void)
+{
+	struct prom_t *_prom = &RELOC(prom);
+	ihandle val;
+
+	if (prom_getprop(_prom->chosen, "stdin", &val, sizeof(val)) > 0)
+		call_prom("close", 1, 0, val);
+}
+
+static int __init prom_find_machine_type(void)
+{
+	struct prom_t *_prom = &RELOC(prom);
+	char compat[256];
+	int len, i = 0;
+	phandle rtas;
+
+	len = prom_getprop(_prom->root, "compatible",
+			   compat, sizeof(compat)-1);
+	if (len > 0) {
+		compat[len] = 0;
+		while (i < len) {
+			char *p = &compat[i];
+			int sl = strlen(p);
+			if (sl == 0)
+				break;
+			if (strstr(p, RELOC("Power Macintosh")) ||
+			    strstr(p, RELOC("MacRISC4")))
+				return PLATFORM_POWERMAC;
+#ifdef CONFIG_PPC64
+			if (strstr(p, RELOC("Momentum,Maple")))
+				return PLATFORM_MAPLE;
+#endif
+			i += sl + 1;
+		}
+	}
+#ifdef CONFIG_PPC64
+	/* Default to pSeries. We need to know if we are running LPAR */
+	rtas = call_prom("finddevice", 1, 1, ADDR("/rtas"));
+	if (PHANDLE_VALID(rtas)) {
+		int x = prom_getproplen(rtas, "ibm,hypertas-functions");
+		if (x != PROM_ERROR) {
+			prom_printf("Hypertas detected, assuming LPAR !\n");
+			return PLATFORM_PSERIES_LPAR;
+		}
+	}
+	return PLATFORM_PSERIES;
+#else
+	return PLATFORM_CHRP;
+#endif
+}
+
+static int __init setup_disp(phandle dp)
+{
+#if defined(CONFIG_BOOTX_TEXT) && defined(CONFIG_PPC32)
+	int width = 640, height = 480, depth = 8, pitch;
+	unsigned address;
+	u32 addrs[8][5];
+	int i, naddrs;
+	char name[32];
+	char *getprop = "getprop";
+
+	prom_printf("Initializing 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 /= 20;
+		for (i = 0; i < naddrs; ++i) {
+			if (addrs[i][4] >= (1 << 20)) {
+				address = addrs[i][2];
+				/* use the BE aperture if possible */
+				if (addrs[i][4] >= (16 << 20))
+					address += (8 << 20);
+				break;
+			}
+		}
+		if (address == 0) {
+			prom_print("Failed to get address\n");
+			return 0;
+		}
+	}
+	/* kludge for valkyrie */
+	if (strcmp(name, "valkyrie") == 0)
+		address += 0x1000;
+
+	prom_printf("\n\n\n\naddress = %x\n", address);
+	btext_setup_display(width, height, depth, pitch, address);
+#endif /* CONFIG_BOOTX_TEXT && CONFIG_PPC32 */
+	return 1;
+}
+
+static int __init prom_set_color(ihandle ih, int i, int r, int g, int b)
+{
+	return call_prom("call-method", 6, 1, ADDR("color!"), ih, i, b, g, r);
+}
+
+/*
+ * 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 void __init prom_check_displays(void)
+{
+	char type[16], *path;
+	phandle node;
+	ihandle ih;
+	int i;
+	int got_display = 0;
+
+	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_printf("Looking for displays\n");
+	for (node = 0; prom_next_node(&node); ) {
+		memset(type, 0, sizeof(type));
+		prom_getprop(node, "device_type", type, sizeof(type));
+		if (strcmp(type, RELOC("display")) != 0)
+			continue;
+
+		/* It seems OF doesn't null-terminate the path :-( */
+		path = RELOC(prom_scratch);
+		memset(path, 0, PROM_SCRATCH_SIZE);
+
+		/*
+		 * leave some room at the end of the path for appending extra
+		 * arguments
+		 */
+		if (call_prom("package-to-path", 3, 1, node, path,
+			      PROM_SCRATCH_SIZE-10) == PROM_ERROR)
+			continue;
+		prom_printf("found display   : %s, opening ... ", path);
+		
+		ih = call_prom("open", 1, 1, path);
+		if (ih == 0) {
+			prom_printf("failed\n");
+			continue;
+		}
+
+		/* Success */
+		prom_printf("done\n");
+		prom_setprop(node, "linux,opened", NULL, 0);
+
+		/* Setup a usable color table when the appropriate
+		 * method is available. Should update this to set-colors */
+		clut = RELOC(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(RELOC(logo_linux_clut224.clut));
+		for (i = 0; i < RELOC(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 (!got_display)
+			got_display = setup_disp(node);
+	}
+}
+
+
+/* Return (relocated) pointer to this much memory: moves initrd if reqd. */
+static void __init *make_room(unsigned long *mem_start, unsigned long *mem_end,
+			      unsigned long needed, unsigned long align)
+{
+	void *ret;
+
+	*mem_start = _ALIGN(*mem_start, align);
+	while ((*mem_start + needed) > *mem_end) {
+		unsigned long room, chunk;
+
+		prom_debug("Chunk exhausted, claiming more at %x...\n",
+			   RELOC(alloc_bottom));
+		room = RELOC(alloc_top) - RELOC(alloc_bottom);
+		if (room > DEVTREE_CHUNK_SIZE)
+			room = DEVTREE_CHUNK_SIZE;
+		if (room < PAGE_SIZE)
+			prom_panic("No memory for flatten_device_tree (no room)");
+		chunk = alloc_up(room, 0);
+		if (chunk == 0)
+			prom_panic("No memory for flatten_device_tree (claim failed)");
+		*mem_end = RELOC(alloc_top);
+	}
+
+	ret = (void *)*mem_start;
+	*mem_start += needed;
+
+	return ret;
+}
+
+#define dt_push_token(token, mem_start, mem_end) \
+	do { *((u32 *)make_room(mem_start, mem_end, 4, 4)) = token; } while(0)
+
+static unsigned long __init dt_find_string(char *str)
+{
+	char *s, *os;
+
+	s = os = (char *)RELOC(dt_string_start);
+	s += 4;
+	while (s <  (char *)RELOC(dt_string_end)) {
+		if (strcmp(s, str) == 0)
+			return s - os;
+		s += strlen(s) + 1;
+	}
+	return 0;
+}
+
+/*
+ * The Open Firmware 1275 specification states properties must be 31 bytes or
+ * less, however not all firmwares obey this. Make it 64 bytes to be safe.
+ */
+#define MAX_PROPERTY_NAME 64
+
+static void __init scan_dt_build_strings(phandle node,
+					 unsigned long *mem_start,
+					 unsigned long *mem_end)
+{
+	char *prev_name, *namep, *sstart;
+	unsigned long soff;
+	phandle child;
+
+	sstart =  (char *)RELOC(dt_string_start);
+
+	/* get and store all property names */
+	prev_name = RELOC("");
+	for (;;) {
+		/* 64 is max len of name including nul. */
+		namep = make_room(mem_start, mem_end, MAX_PROPERTY_NAME, 1);
+		if (call_prom("nextprop", 3, 1, node, prev_name, namep) != 1) {
+			/* No more nodes: unwind alloc */
+			*mem_start = (unsigned long)namep;
+			break;
+		}
+
+ 		/* skip "name" */
+ 		if (strcmp(namep, RELOC("name")) == 0) {
+ 			*mem_start = (unsigned long)namep;
+ 			prev_name = RELOC("name");
+ 			continue;
+ 		}
+		/* get/create string entry */
+		soff = dt_find_string(namep);
+		if (soff != 0) {
+			*mem_start = (unsigned long)namep;
+			namep = sstart + soff;
+		} else {
+			/* Trim off some if we can */
+			*mem_start = (unsigned long)namep + strlen(namep) + 1;
+			RELOC(dt_string_end) = *mem_start;
+		}
+		prev_name = namep;
+	}
+
+	/* do all our children */
+	child = call_prom("child", 1, 1, node);
+	while (child != 0) {
+		scan_dt_build_strings(child, mem_start, mem_end);
+		child = call_prom("peer", 1, 1, child);
+	}
+}
+
+static void __init scan_dt_build_struct(phandle node, unsigned long *mem_start,
+					unsigned long *mem_end)
+{
+	phandle child;
+	char *namep, *prev_name, *sstart, *p, *ep, *lp, *path;
+	unsigned long soff;
+	unsigned char *valp;
+	static char pname[MAX_PROPERTY_NAME];
+	int l;
+
+	dt_push_token(OF_DT_BEGIN_NODE, mem_start, mem_end);
+
+	/* get the node's full name */
+	namep = (char *)*mem_start;
+	l = call_prom("package-to-path", 3, 1, node,
+		      namep, *mem_end - *mem_start);
+	if (l >= 0) {
+		/* Didn't fit?  Get more room. */
+		if ((l+1) > (*mem_end - *mem_start)) {
+			namep = make_room(mem_start, mem_end, l+1, 1);
+			call_prom("package-to-path", 3, 1, node, namep, l);
+		}
+		namep[l] = '\0';
+
+		/* Fixup an Apple bug where they have bogus \0 chars in the
+		 * middle of the path in some properties
+		 */
+		for (p = namep, ep = namep + l; p < ep; p++)
+			if (*p == '\0') {
+				memmove(p, p+1, ep - p);
+				ep--; l--; p--;
+			}
+
+		/* now try to extract the unit name in that mess */
+		for (p = namep, lp = NULL; *p; p++)
+			if (*p == '/')
+				lp = p + 1;
+		if (lp != NULL)
+			memmove(namep, lp, strlen(lp) + 1);
+		*mem_start = _ALIGN(((unsigned long) namep) +
+				    strlen(namep) + 1, 4);
+	}
+
+	/* get it again for debugging */
+	path = RELOC(prom_scratch);
+	memset(path, 0, PROM_SCRATCH_SIZE);
+	call_prom("package-to-path", 3, 1, node, path, PROM_SCRATCH_SIZE-1);
+
+	/* get and store all properties */
+	prev_name = RELOC("");
+	sstart = (char *)RELOC(dt_string_start);
+	for (;;) {
+		if (call_prom("nextprop", 3, 1, node, prev_name,
+			      RELOC(pname)) != 1)
+			break;
+
+ 		/* skip "name" */
+ 		if (strcmp(RELOC(pname), RELOC("name")) == 0) {
+ 			prev_name = RELOC("name");
+ 			continue;
+ 		}
+
+		/* find string offset */
+		soff = dt_find_string(RELOC(pname));
+		if (soff == 0) {
+			prom_printf("WARNING: Can't find string index for"
+				    " <%s>, node %s\n", RELOC(pname), path);
+			break;
+		}
+		prev_name = sstart + soff;
+
+		/* get length */
+		l = call_prom("getproplen", 2, 1, node, RELOC(pname));
+
+		/* sanity checks */
+		if (l == PROM_ERROR)
+			continue;
+		if (l > MAX_PROPERTY_LENGTH) {
+			prom_printf("WARNING: ignoring large property ");
+			/* It seems OF doesn't null-terminate the path :-( */
+			prom_printf("[%s] ", path);
+			prom_printf("%s length 0x%x\n", RELOC(pname), l);
+			continue;
+		}
+
+		/* push property head */
+		dt_push_token(OF_DT_PROP, mem_start, mem_end);
+		dt_push_token(l, mem_start, mem_end);
+		dt_push_token(soff, mem_start, mem_end);
+
+		/* push property content */
+		valp = make_room(mem_start, mem_end, l, 4);
+		call_prom("getprop", 4, 1, node, RELOC(pname), valp, l);
+		*mem_start = _ALIGN(*mem_start, 4);
+	}
+
+	/* Add a "linux,phandle" property. */
+	soff = dt_find_string(RELOC("linux,phandle"));
+	if (soff == 0)
+		prom_printf("WARNING: Can't find string index for"
+			    " <linux-phandle> node %s\n", path);
+	else {
+		dt_push_token(OF_DT_PROP, mem_start, mem_end);
+		dt_push_token(4, mem_start, mem_end);
+		dt_push_token(soff, mem_start, mem_end);
+		valp = make_room(mem_start, mem_end, 4, 4);
+		*(u32 *)valp = node;
+	}
+
+	/* do all our children */
+	child = call_prom("child", 1, 1, node);
+	while (child != 0) {
+		scan_dt_build_struct(child, mem_start, mem_end);
+		child = call_prom("peer", 1, 1, child);
+	}
+
+	dt_push_token(OF_DT_END_NODE, mem_start, mem_end);
+}
+
+static void __init flatten_device_tree(void)
+{
+	phandle root;
+	unsigned long mem_start, mem_end, room;
+	struct boot_param_header *hdr;
+	struct prom_t *_prom = &RELOC(prom);
+	char *namep;
+	u64 *rsvmap;
+
+	/*
+	 * Check how much room we have between alloc top & bottom (+/- a
+	 * few pages), crop to 4Mb, as this is our "chuck" size
+	 */
+	room = RELOC(alloc_top) - RELOC(alloc_bottom) - 0x4000;
+	if (room > DEVTREE_CHUNK_SIZE)
+		room = DEVTREE_CHUNK_SIZE;
+	prom_debug("starting device tree allocs at %x\n", RELOC(alloc_bottom));
+
+	/* Now try to claim that */
+	mem_start = (unsigned long)alloc_up(room, PAGE_SIZE);
+	if (mem_start == 0)
+		prom_panic("Can't allocate initial device-tree chunk\n");
+	mem_end = RELOC(alloc_top);
+
+	/* Get root of tree */
+	root = call_prom("peer", 1, 1, (phandle)0);
+	if (root == (phandle)0)
+		prom_panic ("couldn't get device tree root\n");
+
+	/* Build header and make room for mem rsv map */ 
+	mem_start = _ALIGN(mem_start, 4);
+	hdr = make_room(&mem_start, &mem_end,
+			sizeof(struct boot_param_header), 4);
+	RELOC(dt_header_start) = (unsigned long)hdr;
+	rsvmap = make_room(&mem_start, &mem_end, sizeof(mem_reserve_map), 8);
+
+	/* Start of strings */
+	mem_start = PAGE_ALIGN(mem_start);
+	RELOC(dt_string_start) = mem_start;
+	mem_start += 4; /* hole */
+
+	/* Add "linux,phandle" in there, we'll need it */
+	namep = make_room(&mem_start, &mem_end, 16, 1);
+	strcpy(namep, RELOC("linux,phandle"));
+	mem_start = (unsigned long)namep + strlen(namep) + 1;
+
+	/* Build string array */
+	prom_printf("Building dt strings...\n"); 
+	scan_dt_build_strings(root, &mem_start, &mem_end);
+	RELOC(dt_string_end) = mem_start;
+
+	/* Build structure */
+	mem_start = PAGE_ALIGN(mem_start);
+	RELOC(dt_struct_start) = mem_start;
+	prom_printf("Building dt structure...\n"); 
+	scan_dt_build_struct(root, &mem_start, &mem_end);
+	dt_push_token(OF_DT_END, &mem_start, &mem_end);
+	RELOC(dt_struct_end) = PAGE_ALIGN(mem_start);
+
+	/* Finish header */
+	hdr->boot_cpuid_phys = _prom->cpu;
+	hdr->magic = OF_DT_HEADER;
+	hdr->totalsize = RELOC(dt_struct_end) - RELOC(dt_header_start);
+	hdr->off_dt_struct = RELOC(dt_struct_start) - RELOC(dt_header_start);
+	hdr->off_dt_strings = RELOC(dt_string_start) - RELOC(dt_header_start);
+	hdr->dt_strings_size = RELOC(dt_string_end) - RELOC(dt_string_start);
+	hdr->off_mem_rsvmap = ((unsigned long)rsvmap) - RELOC(dt_header_start);
+	hdr->version = OF_DT_VERSION;
+	/* Version 16 is not backward compatible */
+	hdr->last_comp_version = 0x10;
+
+	/* Reserve the whole thing and copy the reserve map in, we
+	 * also bump mem_reserve_cnt to cause further reservations to
+	 * fail since it's too late.
+	 */
+	reserve_mem(RELOC(dt_header_start), hdr->totalsize);
+	memcpy(rsvmap, RELOC(mem_reserve_map), sizeof(mem_reserve_map));
+
+#ifdef DEBUG_PROM
+	{
+		int i;
+		prom_printf("reserved memory map:\n");
+		for (i = 0; i < RELOC(mem_reserve_cnt); i++)
+			prom_printf("  %x - %x\n",
+				    RELOC(mem_reserve_map)[i].base,
+				    RELOC(mem_reserve_map)[i].size);
+	}
+#endif
+	RELOC(mem_reserve_cnt) = MEM_RESERVE_MAP_SIZE;
+
+	prom_printf("Device tree strings 0x%x -> 0x%x\n",
+		    RELOC(dt_string_start), RELOC(dt_string_end)); 
+	prom_printf("Device tree struct  0x%x -> 0x%x\n",
+		    RELOC(dt_struct_start), RELOC(dt_struct_end));
+
+}
+
+
+static void __init fixup_device_tree(void)
+{
+#if defined(CONFIG_PPC64) && defined(CONFIG_PPC_PMAC)
+	phandle u3, i2c, mpic;
+	u32 u3_rev;
+	u32 interrupts[2];
+	u32 parent;
+
+	/* Some G5s have a missing interrupt definition, fix it up here */
+	u3 = call_prom("finddevice", 1, 1, ADDR("/u3@0,f8000000"));
+	if (!PHANDLE_VALID(u3))
+		return;
+	i2c = call_prom("finddevice", 1, 1, ADDR("/u3@0,f8000000/i2c@f8001000"));
+	if (!PHANDLE_VALID(i2c))
+		return;
+	mpic = call_prom("finddevice", 1, 1, ADDR("/u3@0,f8000000/mpic@f8040000"));
+	if (!PHANDLE_VALID(mpic))
+		return;
+
+	/* check if proper rev of u3 */
+	if (prom_getprop(u3, "device-rev", &u3_rev, sizeof(u3_rev))
+	    == PROM_ERROR)
+		return;
+	if (u3_rev != 0x35 && u3_rev != 0x37)
+		return;
+	/* does it need fixup ? */
+	if (prom_getproplen(i2c, "interrupts") > 0)
+		return;
+
+	prom_printf("fixing up bogus interrupts for u3 i2c...\n");
+
+	/* interrupt on this revision of u3 is number 0 and level */
+	interrupts[0] = 0;
+	interrupts[1] = 1;
+	prom_setprop(i2c, "interrupts", &interrupts, sizeof(interrupts));
+	parent = (u32)mpic;
+	prom_setprop(i2c, "interrupt-parent", &parent, sizeof(parent));
+#endif
+}
+
+
+static void __init prom_find_boot_cpu(void)
+{
+       	struct prom_t *_prom = &RELOC(prom);
+	u32 getprop_rval;
+	ihandle prom_cpu;
+	phandle cpu_pkg;
+
+	if (prom_getprop(_prom->chosen, "cpu", &prom_cpu, sizeof(prom_cpu)) <= 0)
+		prom_panic("cannot find boot cpu");
+
+	cpu_pkg = call_prom("instance-to-package", 1, 1, prom_cpu);
+
+	prom_getprop(cpu_pkg, "reg", &getprop_rval, sizeof(getprop_rval));
+	_prom->cpu = getprop_rval;
+
+	prom_debug("Booting CPU hw index = 0x%x\n", _prom->cpu);
+}
+
+static void __init prom_check_initrd(unsigned long r3, unsigned long r4)
+{
+#ifdef CONFIG_BLK_DEV_INITRD
+       	struct prom_t *_prom = &RELOC(prom);
+
+	if (r3 && r4 && r4 != 0xdeadbeef) {
+		unsigned long val;
+
+		RELOC(prom_initrd_start) = (r3 >= KERNELBASE) ? __pa(r3) : r3;
+		RELOC(prom_initrd_end) = RELOC(prom_initrd_start) + r4;
+
+		val = RELOC(prom_initrd_start);
+		prom_setprop(_prom->chosen, "linux,initrd-start", &val,
+			     sizeof(val));
+		val = RELOC(prom_initrd_end);
+		prom_setprop(_prom->chosen, "linux,initrd-end", &val,
+			     sizeof(val));
+
+		reserve_mem(RELOC(prom_initrd_start),
+			    RELOC(prom_initrd_end) - RELOC(prom_initrd_start));
+
+		prom_debug("initrd_start=0x%x\n", RELOC(prom_initrd_start));
+		prom_debug("initrd_end=0x%x\n", RELOC(prom_initrd_end));
+	}
+#endif /* CONFIG_BLK_DEV_INITRD */
+}
+
+/*
+ * 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(unsigned long r3, unsigned long r4,
+			       unsigned long pp,
+			       unsigned long r6, unsigned long r7)
+{	
+       	struct prom_t *_prom;
+	extern char _stext[];
+	unsigned long hdr;
+	u32 getprop_rval;
+
+#ifdef CONFIG_PPC32
+	unsigned long offset = reloc_offset();
+	reloc_got2(offset);
+#endif
+
+	_prom = &RELOC(prom);
+
+	/*
+	 * First zero the BSS
+	 */
+	memset(&RELOC(__bss_start), 0, __bss_stop - __bss_start);
+
+	/*
+	 * Init interface to Open Firmware, get some node references,
+	 * like /chosen
+	 */
+	prom_init_client_services(pp);
+
+	/*
+	 * Init prom stdout device
+	 */
+	prom_init_stdout();
+
+	/*
+	 * Check for an initrd
+	 */
+	prom_check_initrd(r3, r4);
+
+	/*
+	 * Get default machine type. At this point, we do not differentiate
+	 * between pSeries SMP and pSeries LPAR
+	 */
+	RELOC(of_platform) = prom_find_machine_type();
+	getprop_rval = RELOC(of_platform);
+	prom_setprop(_prom->chosen, "linux,platform",
+		     &getprop_rval, sizeof(getprop_rval));
+
+#ifdef CONFIG_PPC_PSERIES
+	/*
+	 * On pSeries, inform the firmware about our capabilities
+	 */
+	if (RELOC(of_platform) & PLATFORM_PSERIES)
+		prom_send_capabilities();
+#endif
+
+#if defined(CONFIG_PPC_PSERIES) || defined(CONFIG_PPC_BPA)
+	/*
+	 * On pSeries and BPA, copy the CPU hold code
+	 */
+       	if (RELOC(of_platform) & (PLATFORM_PSERIES | PLATFORM_BPA))
+       		copy_and_flush(0, KERNELBASE - offset, 0x100, 0);
+#endif
+
+	/*
+	 * Do early parsing of command line
+	 */
+	early_cmdline_parse();
+
+	/*
+	 * Initialize memory management within prom_init
+	 */
+	prom_init_mem();
+
+	/*
+	 * Determine which cpu is actually running right _now_
+	 */
+	prom_find_boot_cpu();
+
+	/* 
+	 * Initialize display devices
+	 */
+	prom_check_displays();
+
+#ifdef CONFIG_PPC64
+	/*
+	 * Initialize IOMMU (TCE tables) on pSeries. Do that before anything else
+	 * that uses the allocator, we need to make sure we get the top of memory
+	 * available for us here...
+	 */
+	if (RELOC(of_platform) == PLATFORM_PSERIES)
+		prom_initialize_tce_table();
+#endif
+
+	/*
+	 * On non-powermacs, try to instantiate RTAS and puts all CPUs
+	 * in spin-loops. PowerMacs don't have a working RTAS and use
+	 * a different way to spin CPUs
+	 */
+	if (RELOC(of_platform) != PLATFORM_POWERMAC) {
+		prom_instantiate_rtas();
+		prom_hold_cpus();
+	}
+
+	/*
+	 * Fill in some infos for use by the kernel later on
+	 */
+	if (RELOC(prom_memory_limit))
+		prom_setprop(_prom->chosen, "linux,memory-limit",
+			     &RELOC(prom_memory_limit),
+			     sizeof(prom_memory_limit));
+#ifdef CONFIG_PPC64
+	if (RELOC(ppc64_iommu_off))
+		prom_setprop(_prom->chosen, "linux,iommu-off", NULL, 0);
+
+	if (RELOC(iommu_force_on))
+		prom_setprop(_prom->chosen, "linux,iommu-force-on", NULL, 0);
+
+	if (RELOC(prom_tce_alloc_start)) {
+		prom_setprop(_prom->chosen, "linux,tce-alloc-start",
+			     &RELOC(prom_tce_alloc_start),
+			     sizeof(prom_tce_alloc_start));
+		prom_setprop(_prom->chosen, "linux,tce-alloc-end",
+			     &RELOC(prom_tce_alloc_end),
+			     sizeof(prom_tce_alloc_end));
+	}
+#endif
+
+	/*
+	 * Fixup any known bugs in the device-tree
+	 */
+	fixup_device_tree();
+
+	/*
+	 * Now finally create the flattened device-tree
+	 */
+	prom_printf("copying OF device tree ...\n");
+	flatten_device_tree();
+
+	/* in case stdin is USB and still active on IBM machines... */
+	prom_close_stdin();
+
+	/*
+	 * Call OF "quiesce" method to shut down pending DMA's from
+	 * devices etc...
+	 */
+	prom_printf("Calling quiesce ...\n");
+	call_prom("quiesce", 0, 0);
+
+	/*
+	 * And finally, call the kernel passing it the flattened device
+	 * tree and NULL as r5, thus triggering the new entry point which
+	 * is common to us and kexec
+	 */
+	hdr = RELOC(dt_header_start);
+	prom_printf("returning from prom_init\n");
+	prom_debug("->dt_header_start=0x%x\n", hdr);
+
+#ifdef CONFIG_PPC32
+	reloc_got2(-offset);
+#endif
+
+	__start(hdr, 0, 0);
+
+	return 0;
+}