smpboot.c

linux-2.6.15.6

/*
 *  linux/arch/m32r/kernel/smpboot.c
 *    orig : i386 2.4.10
 *
 *  M32R SMP booting functions
 *
 *  Copyright (c) 2001, 2002, 2003  Hitoshi Yamamoto
 *
 *  Taken from i386 version.
 *	  (c) 1995 Alan Cox, Building #3 <[e-mail]>
 *	  (c) 1998, 1999, 2000 Ingo Molnar <[e-mail]>
 *
 *	Much of the core SMP work is based on previous work by Thomas Radke, to
 *	whom a great many thanks are extended.
 *
 *	Thanks to Intel for making available several different Pentium,
 *	Pentium Pro and Pentium-II/Xeon MP machines.
 *	Original development of Linux SMP code supported by Caldera.
 *
 *	This code is released under the GNU General Public License version 2 or
 *	later.
 *
 *	Fixes
 *		Felix Koop	:	NR_CPUS used properly
 *		Jose Renau	:	Handle single CPU case.
 *		Alan Cox	:	By repeated request
 *					8) - Total BogoMIP report.
 *		Greg Wright	:	Fix for kernel stacks panic.
 *		Erich Boleyn	:	MP v1.4 and additional changes.
 *	Matthias Sattler	:	Changes for 2.1 kernel map.
 *	Michel Lespinasse	:	Changes for 2.1 kernel map.
 *	Michael Chastain	:	Change trampoline.S to gnu as.
 *		Alan Cox	:	Dumb bug: 'B' step PPro's are fine
 *		Ingo Molnar	:	Added APIC timers, based on code
 *					from Jose Renau
 *		Ingo Molnar	:	various cleanups and rewrites
 *		Tigran Aivazian	:	fixed "0.00 in /proc/uptime on SMP" bug.
 *	Maciej W. Rozycki	:	Bits for genuine 82489DX APICs
 *		Martin J. Bligh	: 	Added support for multi-quad systems
 */

#include <linux/config.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/smp_lock.h>
#include <linux/irq.h>
#include <linux/bootmem.h>
#include <linux/delay.h>

#include <asm/io.h>
#include <asm/pgalloc.h>
#include <asm/tlbflush.h>

#define DEBUG_SMP
#ifdef DEBUG_SMP
#define Dprintk(x...) printk(x)
#else
#define Dprintk(x...)
#endif

extern cpumask_t cpu_initialized;

/*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*/
/* Data structures and variables                                             */
/*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*/

/* Processor that is doing the boot up */
static unsigned int bsp_phys_id = -1;

/* Bitmask of physically existing CPUs */
physid_mask_t phys_cpu_present_map;

/* Bitmask of currently online CPUs */
cpumask_t cpu_online_map;

cpumask_t cpu_bootout_map;
cpumask_t cpu_bootin_map;
cpumask_t cpu_callout_map;
static cpumask_t cpu_callin_map;

/* Per CPU bogomips and other parameters */
struct cpuinfo_m32r cpu_data[NR_CPUS] __cacheline_aligned;

static int cpucount;
static cpumask_t smp_commenced_mask;

extern struct {
	void * spi;
	unsigned short ss;
} stack_start;

/* which physical physical ID maps to which logical CPU number */
static volatile int physid_2_cpu[NR_CPUS];
#define physid_to_cpu(physid)	physid_2_cpu[physid]

/* which logical CPU number maps to which physical ID */
volatile int cpu_2_physid[NR_CPUS];

DEFINE_PER_CPU(int, prof_multiplier) = 1;
DEFINE_PER_CPU(int, prof_old_multiplier) = 1;
DEFINE_PER_CPU(int, prof_counter) = 1;

spinlock_t ipi_lock[NR_IPIS];

static unsigned int calibration_result;

/*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*/
/* Function Prototypes                                                       */
/*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*/

void smp_prepare_boot_cpu(void);
void smp_prepare_cpus(unsigned int);
static void smp_tune_scheduling(void);
static void init_ipi_lock(void);
static void do_boot_cpu(int);
int __cpu_up(unsigned int);
void smp_cpus_done(unsigned int);

int start_secondary(void *);
static void smp_callin(void);
static void smp_online(void);

static void show_mp_info(int);
static void smp_store_cpu_info(int);
static void show_cpu_info(int);
int setup_profiling_timer(unsigned int);
static void init_cpu_to_physid(void);
static void map_cpu_to_physid(int, int);
static void unmap_cpu_to_physid(int, int);

/*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*/
/* Boot up APs Routins : BSP                                                 */
/*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*/
void __devinit smp_prepare_boot_cpu(void)
{
	bsp_phys_id = hard_smp_processor_id();
	physid_set(bsp_phys_id, phys_cpu_present_map);
	cpu_set(0, cpu_online_map);	/* BSP's cpu_id == 0 */
	cpu_set(0, cpu_callout_map);
	cpu_set(0, cpu_callin_map);

	/*
	 * Initialize the logical to physical CPU number mapping
	 */
	init_cpu_to_physid();
	map_cpu_to_physid(0, bsp_phys_id);
	current_thread_info()->cpu = 0;
}

/*==========================================================================*
 * Name:         smp_prepare_cpus (old smp_boot_cpus)
 *
 * Description:  This routine boot up APs.
 *
 * Born on Date: 2002.02.05
 *
 * Arguments:    NONE
 *
 * Returns:      void (cannot fail)
 *
 * Modification log:
 * Date       Who Description
 * ---------- --- --------------------------------------------------------
 * 2003-06-24 hy  modify for linux-2.5.69
 *
 *==========================================================================*/
void __init smp_prepare_cpus(unsigned int max_cpus)
{
	int phys_id;
	unsigned long nr_cpu;

	nr_cpu = inl(M32R_FPGA_NUM_OF_CPUS_PORTL);
	if (nr_cpu > NR_CPUS) {
		printk(KERN_INFO "NUM_OF_CPUS reg. value [%ld] > NR_CPU [%d]",
			nr_cpu, NR_CPUS);
		goto smp_done;
	}
	for (phys_id = 0 ; phys_id < nr_cpu ; phys_id++)
		physid_set(phys_id, phys_cpu_present_map);

	show_mp_info(nr_cpu);

	init_ipi_lock();

	/*
	 * Setup boot CPU information
	 */
	smp_store_cpu_info(0); /* Final full version of the data */
	smp_tune_scheduling();

	/*
	 * If SMP should be disabled, then really disable it!
	 */
	if (!max_cpus) {
		printk(KERN_INFO "SMP mode deactivated by commandline.\n");
		goto smp_done;
	}

	/*
	 * Now scan the CPU present map and fire up the other CPUs.
	 */
	Dprintk("CPU present map : %lx\n", physids_coerce(phys_cpu_present_map));

	for (phys_id = 0 ; phys_id < NR_CPUS ; phys_id++) {
		/*
		 * Don't even attempt to start the boot CPU!
		 */
		if (phys_id == bsp_phys_id)
			continue;

		if (!physid_isset(phys_id, phys_cpu_present_map))
			continue;

		if ((max_cpus >= 0) && (max_cpus <= cpucount + 1))
			continue;

		do_boot_cpu(phys_id);

		/*
		 * Make sure we unmap all failed CPUs
		 */
		if (physid_to_cpu(phys_id) == -1) {
			physid_clear(phys_id, phys_cpu_present_map);
			printk("phys CPU#%d not responding - " \
				"cannot use it.\n", phys_id);
		}
	}

smp_done:
	Dprintk("Boot done.\n");
}

static void __init smp_tune_scheduling(void)
{
	/* Nothing to do. */
}

/*
 * init_ipi_lock : Initialize IPI locks.
 */
static void __init init_ipi_lock(void)
{
	int ipi;

	for (ipi = 0 ; ipi < NR_IPIS ; ipi++)
		spin_lock_init(&ipi_lock[ipi]);
}

/*==========================================================================*
 * Name:         do_boot_cpu
 *
 * Description:  This routine boot up one AP.
 *
 * Born on Date: 2002.02.05
 *
 * Arguments:    phys_id - Target CPU physical ID
 *
 * Returns:      void (cannot fail)
 *
 * Modification log:
 * Date       Who Description
 * ---------- --- --------------------------------------------------------
 * 2003-06-24 hy  modify for linux-2.5.69
 *
 *==========================================================================*/
static void __init do_boot_cpu(int phys_id)
{
	struct task_struct *idle;
	unsigned long send_status, boot_status;
	int timeout, cpu_id;

	cpu_id = ++cpucount;

	/*
	 * We can't use kernel_thread since we must avoid to
	 * reschedule the child.
	 */
	idle = fork_idle(cpu_id);
	if (IS_ERR(idle))
		panic("failed fork for CPU#%d.", cpu_id);

	idle->thread.lr = (unsigned long)start_secondary;

	map_cpu_to_physid(cpu_id, phys_id);

	/* So we see what's up   */
	printk("Booting processor %d/%d\n", phys_id, cpu_id);
	stack_start.spi = (void *)idle->thread.sp;
	idle->thread_info->cpu = cpu_id;

	/*
	 * Send Startup IPI
	 *   1.IPI received by CPU#(phys_id).
	 *   2.CPU#(phys_id) enter startup_AP (arch/m32r/kernel/head.S)
	 *   3.CPU#(phys_id) enter start_secondary()
	 */
	send_status = 0;
	boot_status = 0;

	cpu_set(phys_id, cpu_bootout_map);

	/* Send Startup IPI */
	send_IPI_mask_phys(cpumask_of_cpu(phys_id), CPU_BOOT_IPI, 0);

	Dprintk("Waiting for send to finish...\n");
	timeout = 0;

	/* Wait 100[ms] */
	do {
		Dprintk("+");
		udelay(1000);
		send_status = !cpu_isset(phys_id, cpu_bootin_map);
	} while (send_status && (timeout++ < 100));

	Dprintk("After Startup.\n");

	if (!send_status) {