arch/powerpc/kernel/setup-common.c - pub/scm/linux/kernel/git/horms/ipvs-next - Git at Google

 /*
  * Common boot and setup code for both 32-bit and 64-bit.
  * Extracted from arch/powerpc/kernel/setup_64.c.
  *
  * Copyright (C) 2001 PPC64 Team, IBM Corp
  *
  *      This program is free software; you can redistribute it and/or
  *      modify it under the terms of the GNU General Public License
  *      as published by the Free Software Foundation; either version
  *      2 of the License, or (at your option) any later version.
  */
 #include <linux/config.h>
 #include <linux/module.h>
 #include <linux/string.h>
 #include <linux/sched.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/reboot.h>
 #include <linux/delay.h>
 #include <linux/initrd.h>
 #include <linux/ide.h>
 #include <linux/seq_file.h>
 #include <linux/ioport.h>
 #include <linux/console.h>
 #include <linux/utsname.h>
 #include <linux/tty.h>
 #include <linux/root_dev.h>
 #include <linux/notifier.h>
 #include <linux/cpu.h>
 #include <linux/unistd.h>
 #include <linux/serial.h>
 #include <linux/serial_8250.h>
 #include <asm/io.h>
 #include <asm/prom.h>
 #include <asm/processor.h>
 #include <asm/vdso_datapage.h>
 #include <asm/pgtable.h>
 #include <asm/smp.h>
 #include <asm/elf.h>
 #include <asm/machdep.h>
 #include <asm/time.h>
 #include <asm/cputable.h>
 #include <asm/sections.h>
 #include <asm/btext.h>
 #include <asm/nvram.h>
 #include <asm/setup.h>
 #include <asm/system.h>
 #include <asm/rtas.h>
 #include <asm/iommu.h>
 #include <asm/serial.h>
 #include <asm/cache.h>
 #include <asm/page.h>
 #include <asm/mmu.h>
 #include <asm/lmb.h>
 #include <asm/xmon.h>

 #include "setup.h"

 #undef DEBUG

 #ifdef DEBUG
 #include <asm/udbg.h>
 #define DBG(fmt...) udbg_printf(fmt)
 #else
 #define DBG(fmt...)
 #endif

 #ifdef CONFIG_PPC_MULTIPLATFORM
 int _machine = 0;
 EXPORT_SYMBOL(_machine);
 #endif

 unsigned long klimit = (unsigned long) _end;

 /*
  * This still seems to be needed... -- paulus
  */
 struct screen_info screen_info = {
 	.orig_x = 0,
 	.orig_y = 25,
 	.orig_video_cols = 80,
 	.orig_video_lines = 25,
 	.orig_video_isVGA = 1,
 	.orig_video_points = 16
 };

 #ifdef __DO_IRQ_CANON
 /* XXX should go elsewhere eventually */
 int ppc_do_canonicalize_irqs;
 EXPORT_SYMBOL(ppc_do_canonicalize_irqs);
 #endif

 /* also used by kexec */
 void machine_shutdown(void)
 {
 	if (ppc_md.machine_shutdown)
 		ppc_md.machine_shutdown();
 }

 void machine_restart(char *cmd)
 {
 	machine_shutdown();
 	if (ppc_md.restart)
 		ppc_md.restart(cmd);
 #ifdef CONFIG_SMP
 	smp_send_stop();
 #endif
 	printk(KERN_EMERG "System Halted, OK to turn off power\n");
 	local_irq_disable();
 	while (1) ;
 }

 void machine_power_off(void)
 {
 	machine_shutdown();
 	if (ppc_md.power_off)
 		ppc_md.power_off();
 #ifdef CONFIG_SMP
 	smp_send_stop();
 #endif
 	printk(KERN_EMERG "System Halted, OK to turn off power\n");
 	local_irq_disable();
 	while (1) ;
 }
 /* Used by the G5 thermal driver */
 EXPORT_SYMBOL_GPL(machine_power_off);

 void (*pm_power_off)(void) = machine_power_off;
 EXPORT_SYMBOL_GPL(pm_power_off);

 void machine_halt(void)
 {
 	machine_shutdown();
 	if (ppc_md.halt)
 		ppc_md.halt();
 #ifdef CONFIG_SMP
 	smp_send_stop();
 #endif
 	printk(KERN_EMERG "System Halted, OK to turn off power\n");
 	local_irq_disable();
 	while (1) ;
 }


 #ifdef CONFIG_TAU
 extern u32 cpu_temp(unsigned long cpu);
 extern u32 cpu_temp_both(unsigned long cpu);
 #endif /* CONFIG_TAU */

 #ifdef CONFIG_SMP
 DEFINE_PER_CPU(unsigned int, pvr);
 #endif

 static int show_cpuinfo(struct seq_file *m, void *v)
 {
 	unsigned long cpu_id = (unsigned long)v - 1;
 	unsigned int pvr;
 	unsigned short maj;
 	unsigned short min;

 	if (cpu_id == NR_CPUS) {
 #if defined(CONFIG_SMP) && defined(CONFIG_PPC32)
 		unsigned long bogosum = 0;
 		int i;
 		for (i = 0; i < NR_CPUS; ++i)
 			if (cpu_online(i))
 				bogosum += loops_per_jiffy;
 		seq_printf(m, "total bogomips\t: %lu.%02lu\n",
 			   bogosum/(500000/HZ), bogosum/(5000/HZ) % 100);
 #endif /* CONFIG_SMP && CONFIG_PPC32 */
 		seq_printf(m, "timebase\t: %lu\n", ppc_tb_freq);

 		if (ppc_md.show_cpuinfo != NULL)
 			ppc_md.show_cpuinfo(m);

 		return 0;
 	}

 	/* We only show online cpus: disable preempt (overzealous, I
 	 * knew) to prevent cpu going down. */
 	preempt_disable();
 	if (!cpu_online(cpu_id)) {
 		preempt_enable();
 		return 0;
 	}

 #ifdef CONFIG_SMP
 	pvr = per_cpu(pvr, cpu_id);
 #else
 	pvr = mfspr(SPRN_PVR);
 #endif
 	maj = (pvr >> 8) & 0xFF;
 	min = pvr & 0xFF;

 	seq_printf(m, "processor\t: %lu\n", cpu_id);
 	seq_printf(m, "cpu\t\t: ");

 	if (cur_cpu_spec->pvr_mask)
 		seq_printf(m, "%s", cur_cpu_spec->cpu_name);
 	else
 		seq_printf(m, "unknown (%08x)", pvr);

 #ifdef CONFIG_ALTIVEC
 	if (cpu_has_feature(CPU_FTR_ALTIVEC))
 		seq_printf(m, ", altivec supported");
 #endif /* CONFIG_ALTIVEC */

 	seq_printf(m, "\n");

 #ifdef CONFIG_TAU
 	if (cur_cpu_spec->cpu_features & CPU_FTR_TAU) {
 #ifdef CONFIG_TAU_AVERAGE
 		/* more straightforward, but potentially misleading */
 		seq_printf(m,  "temperature \t: %u C (uncalibrated)\n",
 			   cpu_temp(cpu_id));
 #else
 		/* show the actual temp sensor range */
 		u32 temp;
 		temp = cpu_temp_both(cpu_id);
 		seq_printf(m, "temperature \t: %u-%u C (uncalibrated)\n",
 			   temp & 0xff, temp >> 16);
 #endif
 	}
 #endif /* CONFIG_TAU */

 	/*
 	 * Assume here that all clock rates are the same in a
 	 * smp system.  -- Cort
 	 */
 	if (ppc_proc_freq)
 		seq_printf(m, "clock\t\t: %lu.%06luMHz\n",
 			   ppc_proc_freq / 1000000, ppc_proc_freq % 1000000);

 	if (ppc_md.show_percpuinfo != NULL)
 		ppc_md.show_percpuinfo(m, cpu_id);

 	/* If we are a Freescale core do a simple check so
 	 * we dont have to keep adding cases in the future */
 	if (PVR_VER(pvr) & 0x8000) {
 		maj = PVR_MAJ(pvr);
 		min = PVR_MIN(pvr);
 	} else {
 		switch (PVR_VER(pvr)) {
 			case 0x0020:	/* 403 family */
 				maj = PVR_MAJ(pvr) + 1;
 				min = PVR_MIN(pvr);
 				break;
 			case 0x1008:	/* 740P/750P ?? */
 				maj = ((pvr >> 8) & 0xFF) - 1;
 				min = pvr & 0xFF;
 				break;
 			default:
 				maj = (pvr >> 8) & 0xFF;
 				min = pvr & 0xFF;
 				break;
 		}
 	}

 	seq_printf(m, "revision\t: %hd.%hd (pvr %04x %04x)\n",
 		   maj, min, PVR_VER(pvr), PVR_REV(pvr));

 #ifdef CONFIG_PPC32
 	seq_printf(m, "bogomips\t: %lu.%02lu\n",
 		   loops_per_jiffy / (500000/HZ),
 		   (loops_per_jiffy / (5000/HZ)) % 100);
 #endif

 #ifdef CONFIG_SMP
 	seq_printf(m, "\n");
 #endif

 	preempt_enable();
 	return 0;
 }

 static void *c_start(struct seq_file *m, loff_t *pos)
 {
 	unsigned long i = *pos;

 	return i <= NR_CPUS ? (void *)(i + 1) : NULL;
 }

 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
 {
 	++*pos;
 	return c_start(m, pos);
 }

 static void c_stop(struct seq_file *m, void *v)
 {
 }

 struct seq_operations cpuinfo_op = {
 	.start =c_start,
 	.next =	c_next,
 	.stop =	c_stop,
 	.show =	show_cpuinfo,
 };

 void __init check_for_initrd(void)
 {
 #ifdef CONFIG_BLK_DEV_INITRD
 	unsigned long *prop;

 	DBG(" -> check_for_initrd()\n");

 	if (of_chosen) {
 		prop = (unsigned long *)get_property(of_chosen,
 				"linux,initrd-start", NULL);
 		if (prop != NULL) {
 			initrd_start = (unsigned long)__va(*prop);
 			prop = (unsigned long *)get_property(of_chosen,
 					"linux,initrd-end", NULL);
 			if (prop != NULL) {
 				initrd_end = (unsigned long)__va(*prop);
 				initrd_below_start_ok = 1;
 			} else
 				initrd_start = 0;
 		}
 	}

 	/* If we were passed an initrd, set the ROOT_DEV properly if the values
 	 * look sensible. If not, clear initrd reference.
 	 */
 	if (is_kernel_addr(initrd_start) && is_kernel_addr(initrd_end) &&
 	    initrd_end > initrd_start)
 		ROOT_DEV = Root_RAM0;
 	else
 		initrd_start = initrd_end = 0;

 	if (initrd_start)
 		printk("Found initrd at 0x%lx:0x%lx\n", initrd_start, initrd_end);

 	DBG(" <- check_for_initrd()\n");
 #endif /* CONFIG_BLK_DEV_INITRD */
 }

 #ifdef CONFIG_SMP

 /**
  * setup_cpu_maps - initialize the following cpu maps:
  *                  cpu_possible_map
  *                  cpu_present_map
  *                  cpu_sibling_map
  *
  * Having the possible map set up early allows us to restrict allocations
  * of things like irqstacks to num_possible_cpus() rather than NR_CPUS.
  *
  * We do not initialize the online map here; cpus set their own bits in
  * cpu_online_map as they come up.
  *
  * This function is valid only for Open Firmware systems.  finish_device_tree
  * must be called before using this.
  *
  * While we're here, we may as well set the "physical" cpu ids in the paca.
  */
 void __init smp_setup_cpu_maps(void)
 {
 	struct device_node *dn = NULL;
 	int cpu = 0;
 	int swap_cpuid = 0;

 	while ((dn = of_find_node_by_type(dn, "cpu")) && cpu < NR_CPUS) {
 		int *intserv;
 		int j, len = sizeof(u32), nthreads = 1;

 		intserv = (int *)get_property(dn, "ibm,ppc-interrupt-server#s",
 					      &len);
 		if (intserv)
 			nthreads = len / sizeof(int);
 		else {
 			intserv = (int *) get_property(dn, "reg", NULL);
 			if (!intserv)
 				intserv = &cpu;	/* assume logical == phys */
 		}

 		for (j = 0; j < nthreads && cpu < NR_CPUS; j++) {
 			cpu_set(cpu, cpu_present_map);
 			set_hard_smp_processor_id(cpu, intserv[j]);

 			if (intserv[j] == boot_cpuid_phys)
 				swap_cpuid = cpu;
 			cpu_set(cpu, cpu_possible_map);
 			cpu++;
 		}
 	}

 	/* Swap CPU id 0 with boot_cpuid_phys, so we can always assume that
 	 * boot cpu is logical 0.
 	 */
 	if (boot_cpuid_phys != get_hard_smp_processor_id(0)) {
 		u32 tmp;
 		tmp = get_hard_smp_processor_id(0);
 		set_hard_smp_processor_id(0, boot_cpuid_phys);
 		set_hard_smp_processor_id(swap_cpuid, tmp);
 	}

 #ifdef CONFIG_PPC64
 	/*
 	 * On pSeries LPAR, we need to know how many cpus
 	 * could possibly be added to this partition.
 	 */
 	if (_machine == PLATFORM_PSERIES_LPAR &&
 	    (dn = of_find_node_by_path("/rtas"))) {
 		int num_addr_cell, num_size_cell, maxcpus;
 		unsigned int *ireg;

 		num_addr_cell = prom_n_addr_cells(dn);
 		num_size_cell = prom_n_size_cells(dn);

 		ireg = (unsigned int *)
 			get_property(dn, "ibm,lrdr-capacity", NULL);

 		if (!ireg)
 			goto out;

 		maxcpus = ireg[num_addr_cell + num_size_cell];

 		/* Double maxcpus for processors which have SMT capability */
 		if (cpu_has_feature(CPU_FTR_SMT))
 			maxcpus *= 2;

 		if (maxcpus > NR_CPUS) {
 			printk(KERN_WARNING
 			       "Partition configured for %d cpus, "
 			       "operating system maximum is %d.\n",
 			       maxcpus, NR_CPUS);
 			maxcpus = NR_CPUS;
 		} else
 			printk(KERN_INFO "Partition configured for %d cpus.\n",
 			       maxcpus);

 		for (cpu = 0; cpu < maxcpus; cpu++)
 			cpu_set(cpu, cpu_possible_map);
 	out:
 		of_node_put(dn);
 	}

 	/*
 	 * Do the sibling map; assume only two threads per processor.
 	 */
 	for_each_cpu(cpu) {
 		cpu_set(cpu, cpu_sibling_map[cpu]);
 		if (cpu_has_feature(CPU_FTR_SMT))
 			cpu_set(cpu ^ 0x1, cpu_sibling_map[cpu]);
 	}

 	vdso_data->processorCount = num_present_cpus();
 #endif /* CONFIG_PPC64 */
 }
 #endif /* CONFIG_SMP */

 #ifdef CONFIG_XMON
 static int __init early_xmon(char *p)
 {
 	/* ensure xmon is enabled */
 	if (p) {
 		if (strncmp(p, "on", 2) == 0)
 			xmon_init(1);
 		if (strncmp(p, "off", 3) == 0)
 			xmon_init(0);
 		if (strncmp(p, "early", 5) != 0)
 			return 0;
 	}
 	xmon_init(1);
 	debugger(NULL);

 	return 0;
 }
 early_param("xmon", early_xmon);
 #endif
	/*
	* Common boot and setup code for both 32-bit and 64-bit.
	* Extracted from arch/powerpc/kernel/setup_64.c.
	*
	* Copyright (C) 2001 PPC64 Team, IBM Corp
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License
	* as published by the Free Software Foundation; either version
	* 2 of the License, or (at your option) any later version.
	*/
	#include <linux/config.h>
	#include <linux/module.h>
	#include <linux/string.h>
	#include <linux/sched.h>
	#include <linux/init.h>
	#include <linux/kernel.h>
	#include <linux/reboot.h>
	#include <linux/delay.h>
	#include <linux/initrd.h>
	#include <linux/ide.h>
	#include <linux/seq_file.h>
	#include <linux/ioport.h>
	#include <linux/console.h>
	#include <linux/utsname.h>
	#include <linux/tty.h>
	#include <linux/root_dev.h>
	#include <linux/notifier.h>
	#include <linux/cpu.h>
	#include <linux/unistd.h>
	#include <linux/serial.h>
	#include <linux/serial_8250.h>
	#include <asm/io.h>
	#include <asm/prom.h>
	#include <asm/processor.h>
	#include <asm/vdso_datapage.h>
	#include <asm/pgtable.h>
	#include <asm/smp.h>
	#include <asm/elf.h>
	#include <asm/machdep.h>
	#include <asm/time.h>
	#include <asm/cputable.h>
	#include <asm/sections.h>
	#include <asm/btext.h>
	#include <asm/nvram.h>
	#include <asm/setup.h>
	#include <asm/system.h>
	#include <asm/rtas.h>
	#include <asm/iommu.h>
	#include <asm/serial.h>
	#include <asm/cache.h>
	#include <asm/page.h>
	#include <asm/mmu.h>
	#include <asm/lmb.h>
	#include <asm/xmon.h>

	#include "setup.h"

	#undef DEBUG

	#ifdef DEBUG
	#include <asm/udbg.h>
	#define DBG(fmt...) udbg_printf(fmt)
	#else
	#define DBG(fmt...)
	#endif

	#ifdef CONFIG_PPC_MULTIPLATFORM
	int _machine = 0;
	EXPORT_SYMBOL(_machine);
	#endif

	unsigned long klimit = (unsigned long) _end;

	/*
	* This still seems to be needed... -- paulus
	*/
	struct screen_info screen_info = {
	.orig_x = 0,
	.orig_y = 25,
	.orig_video_cols = 80,
	.orig_video_lines = 25,
	.orig_video_isVGA = 1,
	.orig_video_points = 16
	};

	#ifdef __DO_IRQ_CANON
	/* XXX should go elsewhere eventually */
	int ppc_do_canonicalize_irqs;
	EXPORT_SYMBOL(ppc_do_canonicalize_irqs);
	#endif

	/* also used by kexec */
	void machine_shutdown(void)
	{
	if (ppc_md.machine_shutdown)
	ppc_md.machine_shutdown();
	}

	void machine_restart(char *cmd)
	{
	machine_shutdown();
	if (ppc_md.restart)
	ppc_md.restart(cmd);
	#ifdef CONFIG_SMP
	smp_send_stop();
	#endif
	printk(KERN_EMERG "System Halted, OK to turn off power\n");
	local_irq_disable();
	while (1) ;
	}

	void machine_power_off(void)
	{
	machine_shutdown();
	if (ppc_md.power_off)
	ppc_md.power_off();
	#ifdef CONFIG_SMP
	smp_send_stop();
	#endif
	printk(KERN_EMERG "System Halted, OK to turn off power\n");
	local_irq_disable();
	while (1) ;
	}
	/* Used by the G5 thermal driver */
	EXPORT_SYMBOL_GPL(machine_power_off);

	void (*pm_power_off)(void) = machine_power_off;
	EXPORT_SYMBOL_GPL(pm_power_off);

	void machine_halt(void)
	{
	machine_shutdown();
	if (ppc_md.halt)
	ppc_md.halt();
	#ifdef CONFIG_SMP
	smp_send_stop();
	#endif
	printk(KERN_EMERG "System Halted, OK to turn off power\n");
	local_irq_disable();
	while (1) ;
	}


	#ifdef CONFIG_TAU
	extern u32 cpu_temp(unsigned long cpu);
	extern u32 cpu_temp_both(unsigned long cpu);
	#endif /* CONFIG_TAU */

	#ifdef CONFIG_SMP
	DEFINE_PER_CPU(unsigned int, pvr);
	#endif

	static int show_cpuinfo(struct seq_file m, void v)
	{
	unsigned long cpu_id = (unsigned long)v - 1;
	unsigned int pvr;
	unsigned short maj;
	unsigned short min;

	if (cpu_id == NR_CPUS) {
	#if defined(CONFIG_SMP) && defined(CONFIG_PPC32)
	unsigned long bogosum = 0;
	int i;
	for (i = 0; i < NR_CPUS; ++i)
	if (cpu_online(i))
	bogosum += loops_per_jiffy;
	seq_printf(m, "total bogomips\t: %lu.%02lu\n",
	bogosum/(500000/HZ), bogosum/(5000/HZ) % 100);
	#endif /* CONFIG_SMP && CONFIG_PPC32 */
	seq_printf(m, "timebase\t: %lu\n", ppc_tb_freq);

	if (ppc_md.show_cpuinfo != NULL)
	ppc_md.show_cpuinfo(m);

	return 0;
	}

	/* We only show online cpus: disable preempt (overzealous, I
	* knew) to prevent cpu going down. */
	preempt_disable();
	if (!cpu_online(cpu_id)) {
	preempt_enable();
	return 0;
	}

	#ifdef CONFIG_SMP
	pvr = per_cpu(pvr, cpu_id);
	#else
	pvr = mfspr(SPRN_PVR);
	#endif
	maj = (pvr >> 8) & 0xFF;
	min = pvr & 0xFF;

	seq_printf(m, "processor\t: %lu\n", cpu_id);
	seq_printf(m, "cpu\t\t: ");

	if (cur_cpu_spec->pvr_mask)
	seq_printf(m, "%s", cur_cpu_spec->cpu_name);
	else
	seq_printf(m, "unknown (%08x)", pvr);

	#ifdef CONFIG_ALTIVEC
	if (cpu_has_feature(CPU_FTR_ALTIVEC))
	seq_printf(m, ", altivec supported");
	#endif /* CONFIG_ALTIVEC */

	seq_printf(m, "\n");

	#ifdef CONFIG_TAU
	if (cur_cpu_spec->cpu_features & CPU_FTR_TAU) {
	#ifdef CONFIG_TAU_AVERAGE
	/* more straightforward, but potentially misleading */
	seq_printf(m, "temperature \t: %u C (uncalibrated)\n",
	cpu_temp(cpu_id));
	#else
	/* show the actual temp sensor range */
	u32 temp;
	temp = cpu_temp_both(cpu_id);
	seq_printf(m, "temperature \t: %u-%u C (uncalibrated)\n",
	temp & 0xff, temp >> 16);
	#endif
	}
	#endif /* CONFIG_TAU */

	/*
	* Assume here that all clock rates are the same in a
	* smp system. -- Cort
	*/
	if (ppc_proc_freq)
	seq_printf(m, "clock\t\t: %lu.%06luMHz\n",
	ppc_proc_freq / 1000000, ppc_proc_freq % 1000000);

	if (ppc_md.show_percpuinfo != NULL)
	ppc_md.show_percpuinfo(m, cpu_id);

	/* If we are a Freescale core do a simple check so
	* we dont have to keep adding cases in the future */
	if (PVR_VER(pvr) & 0x8000) {
	maj = PVR_MAJ(pvr);
	min = PVR_MIN(pvr);
	} else {
	switch (PVR_VER(pvr)) {
	case 0x0020: /* 403 family */
	maj = PVR_MAJ(pvr) + 1;
	min = PVR_MIN(pvr);
	break;
	case 0x1008: /* 740P/750P ?? */
	maj = ((pvr >> 8) & 0xFF) - 1;
	min = pvr & 0xFF;
	break;
	default:
	maj = (pvr >> 8) & 0xFF;
	min = pvr & 0xFF;
	break;
	}
	}

	seq_printf(m, "revision\t: %hd.%hd (pvr %04x %04x)\n",
	maj, min, PVR_VER(pvr), PVR_REV(pvr));

	#ifdef CONFIG_PPC32
	seq_printf(m, "bogomips\t: %lu.%02lu\n",
	loops_per_jiffy / (500000/HZ),
	(loops_per_jiffy / (5000/HZ)) % 100);
	#endif

	#ifdef CONFIG_SMP
	seq_printf(m, "\n");
	#endif

	preempt_enable();
	return 0;
	}

	static void c_start(struct seq_file m, loff_t *pos)
	{
	unsigned long i = *pos;

	return i <= NR_CPUS ? (void *)(i + 1) : NULL;
	}

	static void c_next(struct seq_file m, void v, loff_t pos)
	{
	++*pos;
	return c_start(m, pos);
	}

	static void c_stop(struct seq_file m, void v)
	{
	}

	struct seq_operations cpuinfo_op = {
	.start =c_start,
	.next = c_next,
	.stop = c_stop,
	.show = show_cpuinfo,
	};

	void __init check_for_initrd(void)
	{
	#ifdef CONFIG_BLK_DEV_INITRD
	unsigned long *prop;

	DBG(" -> check_for_initrd()\n");

	if (of_chosen) {
	prop = (unsigned long *)get_property(of_chosen,
	"linux,initrd-start", NULL);
	if (prop != NULL) {
	initrd_start = (unsigned long)__va(*prop);
	prop = (unsigned long *)get_property(of_chosen,
	"linux,initrd-end", NULL);
	if (prop != NULL) {
	initrd_end = (unsigned long)__va(*prop);
	initrd_below_start_ok = 1;
	} else
	initrd_start = 0;
	}
	}

	/* If we were passed an initrd, set the ROOT_DEV properly if the values
	* look sensible. If not, clear initrd reference.
	*/
	if (is_kernel_addr(initrd_start) && is_kernel_addr(initrd_end) &&
	initrd_end > initrd_start)
	ROOT_DEV = Root_RAM0;
	else
	initrd_start = initrd_end = 0;

	if (initrd_start)
	printk("Found initrd at 0x%lx:0x%lx\n", initrd_start, initrd_end);

	DBG(" <- check_for_initrd()\n");
	#endif /* CONFIG_BLK_DEV_INITRD */
	}

	#ifdef CONFIG_SMP

	/**
	* setup_cpu_maps - initialize the following cpu maps:
	* cpu_possible_map
	* cpu_present_map
	* cpu_sibling_map
	*
	* Having the possible map set up early allows us to restrict allocations
	* of things like irqstacks to num_possible_cpus() rather than NR_CPUS.
	*
	* We do not initialize the online map here; cpus set their own bits in
	* cpu_online_map as they come up.
	*
	* This function is valid only for Open Firmware systems. finish_device_tree
	* must be called before using this.
	*
	* While we're here, we may as well set the "physical" cpu ids in the paca.
	*/
	void __init smp_setup_cpu_maps(void)
	{
	struct device_node *dn = NULL;
	int cpu = 0;
	int swap_cpuid = 0;

	while ((dn = of_find_node_by_type(dn, "cpu")) && cpu < NR_CPUS) {
	int *intserv;
	int j, len = sizeof(u32), nthreads = 1;

	intserv = (int *)get_property(dn, "ibm,ppc-interrupt-server#s",
	&len);
	if (intserv)
	nthreads = len / sizeof(int);
	else {
	intserv = (int *) get_property(dn, "reg", NULL);
	if (!intserv)
	intserv = &cpu; /* assume logical == phys */
	}

	for (j = 0; j < nthreads && cpu < NR_CPUS; j++) {
	cpu_set(cpu, cpu_present_map);
	set_hard_smp_processor_id(cpu, intserv[j]);

	if (intserv[j] == boot_cpuid_phys)
	swap_cpuid = cpu;
	cpu_set(cpu, cpu_possible_map);
	cpu++;
	}
	}

	/* Swap CPU id 0 with boot_cpuid_phys, so we can always assume that
	* boot cpu is logical 0.
	*/
	if (boot_cpuid_phys != get_hard_smp_processor_id(0)) {
	u32 tmp;
	tmp = get_hard_smp_processor_id(0);
	set_hard_smp_processor_id(0, boot_cpuid_phys);
	set_hard_smp_processor_id(swap_cpuid, tmp);
	}

	#ifdef CONFIG_PPC64
	/*
	* On pSeries LPAR, we need to know how many cpus
	* could possibly be added to this partition.
	*/
	if (_machine == PLATFORM_PSERIES_LPAR &&
	(dn = of_find_node_by_path("/rtas"))) {
	int num_addr_cell, num_size_cell, maxcpus;
	unsigned int *ireg;

	num_addr_cell = prom_n_addr_cells(dn);
	num_size_cell = prom_n_size_cells(dn);

	ireg = (unsigned int *)
	get_property(dn, "ibm,lrdr-capacity", NULL);

	if (!ireg)
	goto out;

	maxcpus = ireg[num_addr_cell + num_size_cell];

	/* Double maxcpus for processors which have SMT capability */
	if (cpu_has_feature(CPU_FTR_SMT))
	maxcpus *= 2;

	if (maxcpus > NR_CPUS) {
	printk(KERN_WARNING
	"Partition configured for %d cpus, "
	"operating system maximum is %d.\n",
	maxcpus, NR_CPUS);
	maxcpus = NR_CPUS;
	} else
	printk(KERN_INFO "Partition configured for %d cpus.\n",
	maxcpus);

	for (cpu = 0; cpu < maxcpus; cpu++)
	cpu_set(cpu, cpu_possible_map);
	out:
	of_node_put(dn);
	}

	/*
	* Do the sibling map; assume only two threads per processor.
	*/
	for_each_cpu(cpu) {
	cpu_set(cpu, cpu_sibling_map[cpu]);
	if (cpu_has_feature(CPU_FTR_SMT))
	cpu_set(cpu ^ 0x1, cpu_sibling_map[cpu]);
	}

	vdso_data->processorCount = num_present_cpus();
	#endif /* CONFIG_PPC64 */
	}
	#endif /* CONFIG_SMP */

	#ifdef CONFIG_XMON
	static int __init early_xmon(char *p)
	{
	/* ensure xmon is enabled */
	if (p) {
	if (strncmp(p, "on", 2) == 0)
	xmon_init(1);
	if (strncmp(p, "off", 3) == 0)
	xmon_init(0);
	if (strncmp(p, "early", 5) != 0)
	return 0;
	}
	xmon_init(1);
	debugger(NULL);

	return 0;
	}
	early_param("xmon", early_xmon);
	#endif