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smp.c
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smp.c
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/* 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 reschedule_ipi = {
.handler = smp_reschedule_interrupt,
.name = "smp reschedule IPI"
};
static struct irqaction call_function_ipi = {
.handler = smp_call_function_interrupt,
.name = "smp call function IPI"
};
#if !defined(CONFIG_GENERIC_CLOCKEVENTS) || defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST)
static irqreturn_t smp_ipi_timer_interrupt(int irq, void *dev_id);
static struct irqaction local_timer_ipi = {
.handler = smp_ipi_timer_interrupt,
.flags = IRQF_DISABLED,
.name = "smp local timer IPI"
};
#endif
/**
* init_ipi - Initialise the IPI mechanism
*/
static void init_ipi(void)
{
unsigned long flags;
u16 tmp16;
/* set up the reschedule IPI */
irq_set_chip_and_handler(RESCHEDULE_IPI, &mn10300_ipi_type,
handle_percpu_irq);
setup_irq(RESCHEDULE_IPI, &reschedule_ipi);
set_intr_level(RESCHEDULE_IPI, RESCHEDULE_GxICR_LV);
mn10300_ipi_enable(RESCHEDULE_IPI);
/* set up the call function IPI */
irq_set_chip_and_handler(CALL_FUNC_SINGLE_IPI, &mn10300_ipi_type,
handle_percpu_irq);
setup_irq(CALL_FUNC_SINGLE_IPI, &call_function_ipi);
set_intr_level(CALL_FUNC_SINGLE_IPI, CALL_FUNCTION_GxICR_LV);
mn10300_ipi_enable(CALL_FUNC_SINGLE_IPI);
/* set up the local timer IPI */
#if !defined(CONFIG_GENERIC_CLOCKEVENTS) || \
defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST)
irq_set_chip_and_handler(LOCAL_TIMER_IPI, &mn10300_ipi_type,
handle_percpu_irq);
setup_irq(LOCAL_TIMER_IPI, &local_timer_ipi);
set_intr_level(LOCAL_TIMER_IPI, LOCAL_TIMER_GxICR_LV);
mn10300_ipi_enable(LOCAL_TIMER_IPI);
#endif
#ifdef CONFIG_MN10300_CACHE_ENABLED
/* set up the cache flush IPI */
flags = arch_local_cli_save();
__set_intr_stub(NUM2EXCEP_IRQ_LEVEL(FLUSH_CACHE_GxICR_LV),
mn10300_low_ipi_handler);
GxICR(FLUSH_CACHE_IPI) = FLUSH_CACHE_GxICR_LV | GxICR_DETECT;
mn10300_ipi_enable(FLUSH_CACHE_IPI);
arch_local_irq_restore(flags);
#endif
/* set up the NMI call function IPI */
flags = arch_local_cli_save();
GxICR(CALL_FUNCTION_NMI_IPI) = GxICR_NMI | GxICR_ENABLE | GxICR_DETECT;
tmp16 = GxICR(CALL_FUNCTION_NMI_IPI);
arch_local_irq_restore(flags);
/* set up the SMP boot IPI */
flags = arch_local_cli_save();
__set_intr_stub(NUM2EXCEP_IRQ_LEVEL(SMP_BOOT_GxICR_LV),
mn10300_low_ipi_handler);
arch_local_irq_restore(flags);
}
/**
* mn10300_ipi_shutdown - Shut down handling of an IPI
* @irq: The IPI to be shut down.
*/
static void mn10300_ipi_shutdown(unsigned int irq)
{
unsigned long flags;
u16 tmp;
flags = arch_local_cli_save();
tmp = GxICR(irq);
GxICR(irq) = (tmp & GxICR_LEVEL) | GxICR_DETECT;
tmp = GxICR(irq);
arch_local_irq_restore(flags);
}
/**
* mn10300_ipi_enable - Enable an IPI
* @irq: The IPI to be enabled.
*/
static void mn10300_ipi_enable(unsigned int irq)
{
unsigned long flags;
u16 tmp;
flags = arch_local_cli_save();
tmp = GxICR(irq);
GxICR(irq) = (tmp & GxICR_LEVEL) | GxICR_ENABLE;
tmp = GxICR(irq);
arch_local_irq_restore(flags);
}
static void mn10300_ipi_chip_enable(struct irq_data *d)
{
mn10300_ipi_enable(d->irq);
}
/**
* mn10300_ipi_disable - Disable an IPI
* @irq: The IPI to be disabled.
*/
static void mn10300_ipi_disable(unsigned int irq)
{
unsigned long flags;
u16 tmp;
flags = arch_local_cli_save();
tmp = GxICR(irq);
GxICR(irq) = tmp & GxICR_LEVEL;
tmp = GxICR(irq);
arch_local_irq_restore(flags);
}
static void mn10300_ipi_chip_disable(struct irq_data *d)
{
mn10300_ipi_disable(d->irq);
}
/**
* mn10300_ipi_ack - Acknowledge an IPI interrupt in the PIC
* @irq: The IPI to be acknowledged.
*
* Clear the interrupt detection flag for the IPI on the appropriate interrupt
* channel in the PIC.
*/
static void mn10300_ipi_ack(struct irq_data *d)
{
unsigned int irq = d->irq;
unsigned long flags;
u16 tmp;
flags = arch_local_cli_save();
GxICR_u8(irq) = GxICR_DETECT;
tmp = GxICR(irq);
arch_local_irq_restore(flags);
}
/**
* mn10300_ipi_nop - Dummy IPI action
* @irq: The IPI to be acted upon.
*/
static void mn10300_ipi_nop(struct irq_data *d)
{
}
/**
* send_IPI_mask - Send IPIs to all CPUs in list
* @cpumask: The list of CPUs to target.
* @irq: The IPI request to be sent.
*
* Send the specified IPI to all the CPUs in the list, not waiting for them to
* finish before returning. The caller is responsible for synchronisation if
* that is needed.
*/
static void send_IPI_mask(const cpumask_t *cpumask, int irq)
{
int i;
u16 tmp;
for (i = 0; i < NR_CPUS; i++) {
if (cpumask_test_cpu(i, cpumask)) {
/* send IPI */
tmp = CROSS_GxICR(irq, i);
CROSS_GxICR(irq, i) =
tmp | GxICR_REQUEST | GxICR_DETECT;
tmp = CROSS_GxICR(irq, i); /* flush write buffer */
}
}
}
/**
* send_IPI_self - Send an IPI to this CPU.
* @irq: The IPI request to be sent.
*
* Send the specified IPI to the current CPU.
*/
void send_IPI_self(int irq)
{
send_IPI_mask(cpumask_of(smp_processor_id()), irq);
}
/**
* send_IPI_allbutself - Send IPIs to all the other CPUs.
* @irq: The IPI request to be sent.
*
* Send the specified IPI to all CPUs in the system barring the current one,
* not waiting for them to finish before returning. The caller is responsible
* for synchronisation if that is needed.
*/
void send_IPI_allbutself(int irq)
{
cpumask_t cpumask;
cpumask_copy(&cpumask, cpu_online_mask);
cpumask_clear_cpu(smp_processor_id(), &cpumask);
send_IPI_mask(&cpumask, irq);
}
void arch_send_call_function_ipi_mask(const struct cpumask *mask)
{
BUG();
/*send_IPI_mask(mask, CALL_FUNCTION_IPI);*/
}
void arch_send_call_function_single_ipi(int cpu)
{
send_IPI_mask(cpumask_of(cpu), CALL_FUNC_SINGLE_IPI);
}
/**
* smp_send_reschedule - Send reschedule IPI to a CPU
* @cpu: The CPU to target.
*/
void smp_send_reschedule(int cpu)
{
send_IPI_mask(cpumask_of(cpu), RESCHEDULE_IPI);
}
/**
* smp_nmi_call_function - Send a call function NMI IPI to all CPUs
* @func: The function to ask to be run.
* @info: The context data to pass to that function.
* @wait: If true, wait (atomically) until function is run on all CPUs.
*
* Send a non-maskable request to all CPUs in the system, requesting them to
* run the specified function with the given context data, and, potentially, to
* wait for completion of that function on all CPUs.
*
* Returns 0 if successful, -ETIMEDOUT if we were asked to wait, but hit the
* timeout.
*/
int smp_nmi_call_function(smp_call_func_t func, void *info, int wait)
{
struct nmi_call_data_struct data;
unsigned long flags;
unsigned int cnt;
int cpus, ret = 0;
cpus = num_online_cpus() - 1;
if (cpus < 1)
return 0;
data.func = func;
data.info = info;
cpumask_copy(&data.started, cpu_online_mask);
cpumask_clear_cpu(smp_processor_id(), &data.started);
data.wait = wait;
if (wait)
data.finished = data.started;
spin_lock_irqsave(&smp_nmi_call_lock, flags);
nmi_call_data = &data;
smp_mb();
/* Send a message to all other CPUs and wait for them to respond */
send_IPI_allbutself(CALL_FUNCTION_NMI_IPI);
/* Wait for response */
if (CALL_FUNCTION_NMI_IPI_TIMEOUT > 0) {
for (cnt = 0;
cnt < CALL_FUNCTION_NMI_IPI_TIMEOUT &&
!cpumask_empty(&data.started);
cnt++)
mdelay(1);
if (wait && cnt < CALL_FUNCTION_NMI_IPI_TIMEOUT) {
for (cnt = 0;
cnt < CALL_FUNCTION_NMI_IPI_TIMEOUT &&
!cpumask_empty(&data.finished);
cnt++)
mdelay(1);
}
if (cnt >= CALL_FUNCTION_NMI_IPI_TIMEOUT)
ret = -ETIMEDOUT;
} else {
/* If timeout value is zero, wait until cpumask has been
* cleared */
while (!cpumask_empty(&data.started))
barrier();
if (wait)
while (!cpumask_empty(&data.finished))
barrier();
}
spin_unlock_irqrestore(&smp_nmi_call_lock, flags);
return ret;
}
/**
* smp_jump_to_debugger - Make other CPUs enter the debugger by sending an IPI
*
* Send a non-maskable request to all other CPUs in the system, instructing
* them to jump into the debugger. The caller is responsible for checking that
* the other CPUs responded to the instruction.
*
* The caller should make sure that this CPU's debugger IPI is disabled.
*/
void smp_jump_to_debugger(void)
{
if (num_online_cpus() > 1)
/* Send a message to all other CPUs */
send_IPI_allbutself(DEBUGGER_NMI_IPI);
}
/**
* stop_this_cpu - Callback to stop a CPU.
* @unused: Callback context (ignored).
*/
void stop_this_cpu(void *unused)
{
static volatile int stopflag;
unsigned long flags;
#ifdef CONFIG_GDBSTUB
/* In case of single stepping smp_send_stop by other CPU,
* clear procindebug to avoid deadlock.
*/
atomic_set(&procindebug[smp_processor_id()], 0);
#endif /* CONFIG_GDBSTUB */
flags = arch_local_cli_save();
set_cpu_online(smp_processor_id(), false);
while (!stopflag)
cpu_relax();
set_cpu_online(smp_processor_id(), true);
arch_local_irq_restore(flags);
}
/**
* smp_send_stop - Send a stop request to all CPUs.
*/
void smp_send_stop(void)
{
smp_nmi_call_function(stop_this_cpu, NULL, 0);
}
/**
* smp_reschedule_interrupt - Reschedule IPI handler
* @irq: The interrupt number.
* @dev_id: The device ID.
*
* Returns IRQ_HANDLED to indicate we handled the interrupt successfully.
*/
static irqreturn_t smp_reschedule_interrupt(int irq, void *dev_id)
{
scheduler_ipi();
return IRQ_HANDLED;
}
/**
* smp_call_function_interrupt - Call function IPI handler
* @irq: The interrupt number.
* @dev_id: The device ID.
*
* Returns IRQ_HANDLED to indicate we handled the interrupt successfully.
*/
static irqreturn_t smp_call_function_interrupt(int irq, void *dev_id)
{
/* generic_smp_call_function_interrupt(); */
generic_smp_call_function_single_interrupt();
return IRQ_HANDLED;
}
/**
* smp_nmi_call_function_interrupt - Non-maskable call function IPI handler
*/
void smp_nmi_call_function_interrupt(void)
{
smp_call_func_t func = nmi_call_data->func;
void *info = nmi_call_data->info;
int wait = nmi_call_data->wait;
/* Notify the initiating CPU that I've grabbed the data and am about to
* execute the function
*/
smp_mb();
cpumask_clear_cpu(smp_processor_id(), &nmi_call_data->started);
(*func)(info);
if (wait) {
smp_mb();
cpumask_clear_cpu(smp_processor_id(),
&nmi_call_data->finished);
}
}
#if !defined(CONFIG_GENERIC_CLOCKEVENTS) || \
defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST)
/**
* smp_ipi_timer_interrupt - Local timer IPI handler
* @irq: The interrupt number.
* @dev_id: The device ID.
*
* Returns IRQ_HANDLED to indicate we handled the interrupt successfully.
*/
static irqreturn_t smp_ipi_timer_interrupt(int irq, void *dev_id)
{
return local_timer_interrupt();
}
#endif
void __init smp_init_cpus(void)
{
int i;
for (i = 0; i < NR_CPUS; i++) {
set_cpu_possible(i, true);
set_cpu_present(i, true);
}
}
/**
* smp_cpu_init - Initialise AP in start_secondary.
*
* For this Application Processor, set up init_mm, initialise FPU and set
* interrupt level 0-6 setting.
*/
static void __init smp_cpu_init(void)
{
unsigned long flags;
int cpu_id = smp_processor_id();
u16 tmp16;
if (test_and_set_bit(cpu_id, &cpu_initialized)) {
printk(KERN_WARNING "CPU#%d already initialized!\n", cpu_id);
for (;;)
local_irq_enable();
}
printk(KERN_INFO "Initializing CPU#%d\n", cpu_id);
atomic_inc(&init_mm.mm_count);
current->active_mm = &init_mm;
BUG_ON(current->mm);
enter_lazy_tlb(&init_mm, current);
/* Force FPU initialization */
clear_using_fpu(current);
GxICR(CALL_FUNC_SINGLE_IPI) = CALL_FUNCTION_GxICR_LV | GxICR_DETECT;
mn10300_ipi_enable(CALL_FUNC_SINGLE_IPI);
GxICR(LOCAL_TIMER_IPI) = LOCAL_TIMER_GxICR_LV | GxICR_DETECT;
mn10300_ipi_enable(LOCAL_TIMER_IPI);
GxICR(RESCHEDULE_IPI) = RESCHEDULE_GxICR_LV | GxICR_DETECT;
mn10300_ipi_enable(RESCHEDULE_IPI);
#ifdef CONFIG_MN10300_CACHE_ENABLED
GxICR(FLUSH_CACHE_IPI) = FLUSH_CACHE_GxICR_LV | GxICR_DETECT;
mn10300_ipi_enable(FLUSH_CACHE_IPI);
#endif
mn10300_ipi_shutdown(SMP_BOOT_IRQ);
/* Set up the non-maskable call function IPI */
flags = arch_local_cli_save();
GxICR(CALL_FUNCTION_NMI_IPI) = GxICR_NMI | GxICR_ENABLE | GxICR_DETECT;
tmp16 = GxICR(CALL_FUNCTION_NMI_IPI);
arch_local_irq_restore(flags);
}
/**
* smp_prepare_cpu_init - Initialise CPU in startup_secondary
*
* Set interrupt level 0-6 setting and init ICR of the kernel debugger.
*/
void smp_prepare_cpu_init(void)
{
int loop;
/* Set the interrupt vector registers */
IVAR0 = EXCEP_IRQ_LEVEL0;
IVAR1 = EXCEP_IRQ_LEVEL1;
IVAR2 = EXCEP_IRQ_LEVEL2;
IVAR3 = EXCEP_IRQ_LEVEL3;
IVAR4 = EXCEP_IRQ_LEVEL4;
IVAR5 = EXCEP_IRQ_LEVEL5;
IVAR6 = EXCEP_IRQ_LEVEL6;
/* Disable all interrupts and set to priority 6 (lowest) */
for (loop = 0; loop < GxICR_NUM_IRQS; loop++)
GxICR(loop) = GxICR_LEVEL_6 | GxICR_DETECT;
#ifdef CONFIG_KERNEL_DEBUGGER
/* initialise the kernel debugger interrupt */
do {
unsigned long flags;
u16 tmp16;
flags = arch_local_cli_save();
GxICR(DEBUGGER_NMI_IPI) = GxICR_NMI | GxICR_ENABLE | GxICR_DETECT;
tmp16 = GxICR(DEBUGGER_NMI_IPI);
arch_local_irq_restore(flags);
} while (0);
#endif
}
/**
* start_secondary - Activate a secondary CPU (AP)
* @unused: Thread parameter (ignored).
*/
int __init start_secondary(void *unused)
{
smp_cpu_init();
smp_callin();
while (!cpumask_test_cpu(smp_processor_id(), &smp_commenced_mask))
cpu_relax();
local_flush_tlb();
preempt_disable();
smp_online();
#ifdef CONFIG_GENERIC_CLOCKEVENTS
init_clockevents();
#endif
cpu_idle();
return 0;
}
/**
* smp_prepare_cpus - Boot up secondary CPUs (APs)
* @max_cpus: Maximum number of CPUs to boot.
*
* Call do_boot_cpu, and boot up APs.
*/
void __init smp_prepare_cpus(unsigned int max_cpus)
{
int phy_id;
/* Setup boot CPU information */
smp_store_cpu_info(0);
smp_tune_scheduling();
init_ipi();
/* If SMP should be disabled, then finish */
if (max_cpus == 0) {
printk(KERN_INFO "SMP mode deactivated.\n");
goto smp_done;
}
/* Boot secondary CPUs (for which phy_id > 0) */
for (phy_id = 0; phy_id < NR_CPUS; phy_id++) {
/* Don't boot primary CPU */
if (max_cpus <= cpucount + 1)
continue;
if (phy_id != 0)
do_boot_cpu(phy_id);
set_cpu_possible(phy_id, true);
smp_show_cpu_info(phy_id);
}
smp_done:
Dprintk("Boot done.\n");
}
/**
* smp_store_cpu_info - Save a CPU's information
* @cpu: The CPU to save for.
*
* Save boot_cpu_data and jiffy for the specified CPU.
*/
static void __init smp_store_cpu_info(int cpu)
{
struct mn10300_cpuinfo *ci = &cpu_data[cpu];
*ci = boot_cpu_data;
ci->loops_per_jiffy = loops_per_jiffy;
ci->type = CPUREV;
}
/**
* smp_tune_scheduling - Set time slice value
*
* Nothing to do here.
*/
static void __init smp_tune_scheduling(void)
{
}
/**
* do_boot_cpu: Boot up one CPU
* @phy_id: Physical ID of CPU to boot.
*
* Send an IPI to a secondary CPU to boot it. Returns 0 on success, 1
* otherwise.
*/
static int __init do_boot_cpu(int phy_id)
{
struct task_struct *idle;
unsigned long send_status, callin_status;
int timeout, cpu_id;
send_status = GxICR_REQUEST;
callin_status = 0;
timeout = 0;
cpu_id = phy_id;
cpucount++;
/* Create idle thread for this CPU */
idle = fork_idle(cpu_id);
if (IS_ERR(idle))
panic("Failed fork for CPU#%d.", cpu_id);
idle->thread.pc = (unsigned long)start_secondary;
printk(KERN_NOTICE "Booting CPU#%d\n", cpu_id);
start_stack[cpu_id - 1] = idle->thread.sp;
task_thread_info(idle)->cpu = cpu_id;
/* Send boot IPI to AP */
send_IPI_mask(cpumask_of(phy_id), SMP_BOOT_IRQ);
Dprintk("Waiting for send to finish...\n");
/* Wait for AP's IPI receive in 100[ms] */
do {
udelay(1000);
send_status =
CROSS_GxICR(SMP_BOOT_IRQ, phy_id) & GxICR_REQUEST;
} while (send_status == GxICR_REQUEST && timeout++ < 100);
Dprintk("Waiting for cpu_callin_map.\n");
if (send_status == 0) {
/* Allow AP to start initializing */
cpumask_set_cpu(cpu_id, &cpu_callout_map);
/* Wait for setting cpu_callin_map */
timeout = 0;
do {
udelay(1000);
callin_status = cpumask_test_cpu(cpu_id,
&cpu_callin_map);
} while (callin_status == 0 && timeout++ < 5000);
if (callin_status == 0)
Dprintk("Not responding.\n");
} else {
printk(KERN_WARNING "IPI not delivered.\n");
}
if (send_status == GxICR_REQUEST || callin_status == 0) {
cpumask_clear_cpu(cpu_id, &cpu_callout_map);
cpumask_clear_cpu(cpu_id, &cpu_callin_map);
cpumask_clear_cpu(cpu_id, &cpu_initialized);
cpucount--;
return 1;
}
return 0;
}
/**
* smp_show_cpu_info - Show SMP CPU information
* @cpu: The CPU of interest.
*/
static void __init smp_show_cpu_info(int cpu)
{
struct mn10300_cpuinfo *ci = &cpu_data[cpu];
printk(KERN_INFO
"CPU#%d : ioclk speed: %lu.%02luMHz : bogomips : %lu.%02lu\n",
cpu,
MN10300_IOCLK / 1000000,
(MN10300_IOCLK / 10000) % 100,
ci->loops_per_jiffy / (500000 / HZ),
(ci->loops_per_jiffy / (5000 / HZ)) % 100);
}
/**
* smp_callin - Set cpu_callin_map of the current CPU ID
*/
static void __init smp_callin(void)
{
unsigned long timeout;
int cpu;
cpu = smp_processor_id();
timeout = jiffies + (2 * HZ);
if (cpumask_test_cpu(cpu, &cpu_callin_map)) {
printk(KERN_ERR "CPU#%d already present.\n", cpu);
BUG();
}
Dprintk("CPU#%d waiting for CALLOUT\n", cpu);
/* Wait for AP startup 2s total */
while (time_before(jiffies, timeout)) {
if (cpumask_test_cpu(cpu, &cpu_callout_map))
break;
cpu_relax();
}
if (!time_before(jiffies, timeout)) {
printk(KERN_ERR
"BUG: CPU#%d started up but did not get a callout!\n",
cpu);
BUG();
}
#ifdef CONFIG_CALIBRATE_DELAY
calibrate_delay(); /* Get our bogomips */
#endif
/* Save our processor parameters */
smp_store_cpu_info(cpu);
/* Allow the boot processor to continue */
cpumask_set_cpu(cpu, &cpu_callin_map);
}
/**
* smp_online - Set cpu_online_mask
*/
static void __init smp_online(void)
{
int cpu;
cpu = smp_processor_id();
notify_cpu_starting(cpu);
set_cpu_online(cpu, true);
local_irq_enable();
}
/**
* smp_cpus_done -
* @max_cpus: Maximum CPU count.
*
* Do nothing.
*/
void __init smp_cpus_done(unsigned int max_cpus)
{
}
/*
* smp_prepare_boot_cpu - Set up stuff for the boot processor.
*
* Set up the cpu_online_mask, cpu_callout_map and cpu_callin_map of the boot
* processor (CPU 0).
*/
void __devinit smp_prepare_boot_cpu(void)
{
cpumask_set_cpu(0, &cpu_callout_map);
cpumask_set_cpu(0, &cpu_callin_map);
current_thread_info()->cpu = 0;
}
/*
* initialize_secondary - Initialise a secondary CPU (Application Processor).
*
* Set SP register and jump to thread's PC address.
*/
void initialize_secondary(void)
{
asm volatile (
"mov %0,sp \n"
"jmp (%1) \n"
:
: "a"(current->thread.sp), "a"(current->thread.pc));
}
/**
* __cpu_up - Set smp_commenced_mask for the nominated CPU
* @cpu: The target CPU.
*/
int __devinit __cpu_up(unsigned int cpu, struct task_struct *tidle)
{
int timeout;
#ifdef CONFIG_HOTPLUG_CPU
if (num_online_cpus() == 1)
disable_hlt();
if (sleep_mode[cpu])
run_wakeup_cpu(cpu);
#endif /* CONFIG_HOTPLUG_CPU */
cpumask_set_cpu(cpu, &smp_commenced_mask);
/* Wait 5s total for a response */
for (timeout = 0 ; timeout < 5000 ; timeout++) {
if (cpu_online(cpu))
break;
udelay(1000);
}
BUG_ON(!cpu_online(cpu));
return 0;
}
/**
* setup_profiling_timer - Set up the profiling timer
* @multiplier - The frequency multiplier to use
*
* The frequency of the profiling timer can be changed by writing a multiplier
* value into /proc/profile.
*/
int setup_profiling_timer(unsigned int multiplier)
{
return -EINVAL;
}
/*
* CPU hotplug routines
*/
#ifdef CONFIG_HOTPLUG_CPU
static DEFINE_PER_CPU(struct cpu, cpu_devices);
static int __init topology_init(void)
{
int cpu, ret;
for_each_cpu(cpu) {
ret = register_cpu(&per_cpu(cpu_devices, cpu), cpu, NULL);
if (ret)
printk(KERN_WARNING
"topology_init: register_cpu %d failed (%d)\n",
cpu, ret);
}
return 0;
}
subsys_initcall(topology_init);
int __cpu_disable(void)
{
int cpu = smp_processor_id();
if (cpu == 0)
return -EBUSY;
migrate_irqs();
cpumask_clear_cpu(cpu, &mm_cpumask(current->active_mm));
return 0;
}
void __cpu_die(unsigned int cpu)
{
run_sleep_cpu(cpu);
if (num_online_cpus() == 1)
enable_hlt();