path: root/arch/mn10300/kernel/smp.c

/* SMP support routines.
 *
 * Copyright (C) 2006-2008 Panasonic Corporation
 * All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 */

#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/init.h>
#include <linux/jiffies.h>
#include <linux/cpumask.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/sched.h>
#include <linux/profile.h>
#include <linux/smp.h>
#include <linux/cpu.h>
#include <asm/tlbflush.h>
#include <asm/bitops.h>
#include <asm/processor.h>
#include <asm/bug.h>
#include <asm/exceptions.h>
#include <asm/hardirq.h>
#include <asm/fpu.h>
#include <asm/mmu_context.h>
#include <asm/thread_info.h>
#include <asm/cpu-regs.h>
#include <asm/intctl-regs.h>
#include "internal.h"

#ifdef CONFIG_HOTPLUG_CPU
#include <asm/cacheflush.h>

static unsigned long sleep_mode[NR_CPUS];

static void run_sleep_cpu(unsigned int cpu);
static void run_wakeup_cpu(unsigned int cpu);
#endif /* CONFIG_HOTPLUG_CPU */

/*
 * Debug Message function
 */

#undef DEBUG_SMP
#ifdef DEBUG_SMP
#define Dprintk(fmt, ...) printk(KERN_DEBUG fmt, ##__VA_ARGS__)
#else
#define Dprintk(fmt, ...) no_printk(KERN_DEBUG fmt, ##__VA_ARGS__)
#endif

/* timeout value in msec for smp_nmi_call_function. zero is no timeout. */
#define	CALL_FUNCTION_NMI_IPI_TIMEOUT	0

/*
 * Structure and data for smp_nmi_call_function().
 */
struct nmi_call_data_struct {
	smp_call_func_t	func;
	void		*info;
	cpumask_t	started;
	cpumask_t	finished;
	int		wait;
	char		size_alignment[0]
	__attribute__ ((__aligned__(SMP_CACHE_BYTES)));
} __attribute__ ((__aligned__(SMP_CACHE_BYTES)));

static DEFINE_SPINLOCK(smp_nmi_call_lock);
static struct nmi_call_data_struct *nmi_call_data;

/*
 * Data structures and variables
 */
static cpumask_t cpu_callin_map;	/* Bitmask of callin CPUs */
static cpumask_t cpu_callout_map;	/* Bitmask of callout CPUs */
cpumask_t cpu_boot_map;			/* Bitmask of boot APs */
unsigned long start_stack[NR_CPUS - 1];

/*
 * Per CPU parameters
 */
struct mn10300_cpuinfo cpu_data[NR_CPUS] __cacheline_aligned;

static int cpucount;			/* The count of boot CPUs */
static cpumask_t smp_commenced_mask;
cpumask_t cpu_initialized __initdata = CPU_MASK_NONE;

/*
 * Function Prototypes
 */
static int do_boot_cpu(int);
static void smp_show_cpu_info(int cpu_id);
static void smp_callin(void);
static void smp_online(void);
static void smp_store_cpu_info(int);
static void smp_cpu_init(void);
static void smp_tune_scheduling(void);
static void send_IPI_mask(const cpumask_t *cpumask, int irq);
static void init_ipi(void);

/*
 * IPI Initialization interrupt definitions
 */
static void mn10300_ipi_disable(unsigned int irq);
static void mn10300_ipi_enable(unsigned int irq);
static void mn10300_ipi_chip_disable(struct irq_data *d);
static void mn10300_ipi_chip_enable(struct irq_data *d);
static void mn10300_ipi_ack(struct irq_data *d);
static void mn10300_ipi_nop(struct irq_data *d);

static struct irq_chip mn10300_ipi_type = {
	.name		= "cpu_ipi",
	.irq_disable	= mn10300_ipi_chip_disable,
	.irq_enable	= mn10300_ipi_chip_enable,
	.irq_ack	= mn10300_ipi_ack,
	.irq_eoi	= mn10300_ipi_nop
};

static irqreturn_t smp_reschedule_interrupt(int irq, void *dev_id);
static irqreturn_t smp_call_function_interrupt(int irq, void *dev_id);

static struct irqaction