[deliverable/linux.git] / arch / parisc / kernel / smp.c

/*
** SMP Support
**
** Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
** Copyright (C) 1999 David Mosberger-Tang <davidm@hpl.hp.com>
** Copyright (C) 2001,2004 Grant Grundler <grundler@parisc-linux.org>
** 
** Lots of stuff stolen from arch/alpha/kernel/smp.c
** ...and then parisc stole from arch/ia64/kernel/smp.c. Thanks David! :^)
**
** Thanks to John Curry and Ullas Ponnadi. I learned alot from their work.
** -grant (1/12/2001)
**
**	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 ENTRY_SYS_CPUS	/* syscall support for iCOD-like functionality */


#include <linux/types.h>
#include <linux/spinlock.h>
#include <linux/slab.h>

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/smp.h>
#include <linux/kernel_stat.h>
#include <linux/mm.h>
#include <linux/delay.h>
#include <linux/bitops.h>

#include <asm/system.h>
#include <asm/atomic.h>
#include <asm/current.h>
#include <asm/delay.h>
#include <asm/tlbflush.h>

#include <asm/io.h>
#include <asm/irq.h>		/* for CPU_IRQ_REGION and friends */
#include <asm/mmu_context.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <asm/processor.h>
#include <asm/ptrace.h>
#include <asm/unistd.h>
#include <asm/cacheflush.h>

#define kDEBUG 0

DEFINE_SPINLOCK(smp_lock);

volatile struct task_struct *smp_init_current_idle_task;

static volatile int cpu_now_booting __read_mostly = 0;	/* track which CPU is booting */

static int parisc_max_cpus __read_mostly = 1;

/* online cpus are ones that we've managed to bring up completely
 * possible cpus are all valid cpu 
 * present cpus are all detected cpu
 *
 * On startup we bring up the "possible" cpus. Since we discover
 * CPUs later, we add them as hotplug, so the possible cpu mask is
 * empty in the beginning.
 */

cpumask_t cpu_online_map   __read_mostly = CPU_MASK_NONE;	/* Bitmap of online CPUs */
cpumask_t cpu_possible_map __read_mostly = CPU_MASK_ALL;	/* Bitmap of Present CPUs */

EXPORT_SYMBOL(cpu_online_map);
EXPORT_SYMBOL(cpu_possible_map);


struct smp_call_struct {
	void (*func) (void *info);
	void *info;
	long wait;
	atomic_t unstarted_count;
	atomic_t unfinished_count;
};
static volatile struct smp_call_struct *smp_call_function_data;

enum ipi_message_type {
	IPI_NOP=0,
	IPI_RESCHEDULE=1,
	IPI_CALL_FUNC,
	IPI_CPU_START,
	IPI_CPU_STOP,
	IPI_CPU_TEST
};


/********** SMP inter processor interrupt and communication routines */

#undef PER_CPU_IRQ_REGION
#ifdef PER_CPU_IRQ_REGION
/* XXX REVISIT Ignore for now.
**    *May* need this "hook" to register IPI handler
**    once we have perCPU ExtIntr switch tables.
*/
static void
ipi_init(int cpuid)
{

	/* If CPU is present ... */
#ifdef ENTRY_SYS_CPUS
	/* *and* running (not stopped) ... */
#error iCOD support wants state checked here.
#endif

#error verify IRQ_OFFSET(IPI_IRQ) is ipi_interrupt() in new IRQ region

	if(cpu_online(cpuid) )
	{
		switch_to_idle_task(current);
	}

	return;
}
#endif


/*
** Yoink this CPU from the runnable list... 
**
*/
static void
halt_processor(void) 
{
#ifdef ENTRY_SYS_CPUS
#error halt_processor() needs rework
/*
** o migrate I/O interrupts off this CPU.
** o leave IPI enabled - __cli() will disable IPI.
** o leave CPU in online map - just change the state
*/
	cpu_data[this_cpu].state = STATE_STOPPED;
	mark_bh(IPI_BH);
#else
	/* REVISIT : redirect I/O Interrupts to another CPU? */
	/* REVISIT : does PM *know* this CPU isn't available? */
	cpu_clear(smp_processor_id(), cpu_online_map);
	local_irq_disable();
	for (;;)
		;
#endif
}


irqreturn_t
ipi_interrupt(int irq, void *dev_id, struct pt_regs *regs) 
{
	int this_cpu = smp_processor_id();
	struct cpuinfo_parisc *p = &cpu_data[this_cpu];
	unsigned long ops;
	unsigned long flags;

	/* Count this now; we may make a call that never returns. */
	p->ipi_count++;

	mb();	/* Order interrupt and bit testing. */

	for (;;) {
		spin_lock_irqsave(&(p->lock),flags);
		ops = p->pending_ipi;
		p->pending_ipi = 0;
		spin_unlock_irqrestore(&(p->lock),flags);

		mb(); /* Order bit clearing and data access. */

		if (!ops)
		    break;

		while (ops) {
			unsigned long which = ffz(~ops);

			ops &= ~(1 << which);

			switch (which) {
			case IPI_NOP:
#if (kDEBUG>=100)
				printk(KERN_DEBUG "CPU%d IPI_NOP\n",this_cpu);
#endif /* kDEBUG */
				break;
				
			case IPI_RESCHEDULE:
#if (kDEBUG>=100)
				printk(KERN_DEBUG "CPU%d IPI_RESCHEDULE\n",this_cpu);
#endif /* kDEBUG */
				/*
				 * Reschedule callback.  Everything to be
				 * done is done by the interrupt return path.
				 */
				break;

			case IPI_CALL_FUNC:
#if (kDEBUG>=100)
				printk(KERN_DEBUG "CPU%d IPI_CALL_FUNC\n",this_cpu);
#endif /* kDEBUG */
				{
					volatile struct smp_call_struct *data;
					void (*func)(void *info);
					void *info;
					int wait;

					data = smp_call_function_data;
					func = data->func;
					info = data->info;
					wait = data->wait;

					mb();
					atomic_dec ((atomic_t *)&data->unstarted_count);

					/* At this point, *data can't
					 * be relied upon.
					 */

					(*func)(info);

					/* Notify the sending CPU that the
					 * task is done.
					 */
					mb();
					if (wait)
						atomic_dec ((atomic_t *)&data->unfinished_count);
				}
				break;

			case IPI_CPU_START:
#if (kDEBUG>=100)
				printk(KERN_DEBUG "CPU%d IPI_CPU_START\n",this_cpu);
#endif /* kDEBUG */
#ifdef ENTRY_SYS_CPUS
				p->state = STATE_RUNNING;
#endif
				break;

			case IPI_CPU_STOP:
#if (kDEBUG>=100)
				printk(KERN_DEBUG "CPU%d IPI_CPU_STOP\n",this_cpu);
#endif /* kDEBUG */
#ifdef ENTRY_SYS_CPUS
#else
				halt_processor();
#endif
				break;

			case IPI_CPU_TEST:
#if (kDEBUG>=100)
				printk(KERN_DEBUG "CPU%d is alive!\n",this_cpu);
#endif /* kDEBUG */
				break;

			default:
				printk(KERN_CRIT "Unknown IPI num on CPU%d: %lu\n",
					this_cpu, which);
				return IRQ_NONE;
			} /* Switch */
		} /* while (ops) */
	}
	return IRQ_HANDLED;
}


static inline void
ipi_send(int cpu, enum ipi_message_type op)
{
	struct cpuinfo_parisc *p = &cpu_data[cpu];
	unsigned long flags;

	spin_lock_irqsave(&(p->lock),flags);
	p->pending_ipi |= 1 << op;
	gsc_writel(IPI_IRQ - CPU_IRQ_BASE, cpu_data[cpu].hpa);
	spin_unlock_irqrestore(&(p->lock),flags);
}


static inline void
send_IPI_single(int dest_cpu, enum ipi_message_type op)
{
	if (dest_cpu == NO_PROC_ID) {
		BUG();
		return;
	}

	ipi_send(dest_cpu, op);
}

static inline void
send_IPI_allbutself(enum ipi_message_type op)
{
	int i;
	
	for_each_online_cpu(i) {
		if (i != smp_processor_id())
			send_IPI_single(i, op);
	}
}


inline void 
smp_send_stop(void)	{ send_IPI_allbutself(IPI_CPU_STOP); }

static inline void
smp_send_start(void)	{ send_IPI_allbutself(IPI_CPU_START); }

void 
smp_send_reschedule(int cpu) { send_IPI_single(cpu, IPI_RESCHEDULE); }

void
smp_send_all_nop(void)
{
	send_IPI_allbutself(IPI_NOP);
}


/**
 * Run a function on all other CPUs.
 *  <func>	The function to run. This must be fast and non-blocking.
 *  <info>	An arbitrary pointer to pass to the function.
 *  <retry>	If true, keep retrying until ready.
 *  <wait>	If true, wait until function has completed on other CPUs.
 *  [RETURNS]   0 on success, else a negative status code.
 *
 * Does not return until remote CPUs are nearly ready to execute <func>
 * or have executed.
 */

int
smp_call_function (void (*func) (void *info), void *info, int retry, int wait)
{
	struct smp_call_struct data;
	unsigned long timeout;
	static DEFINE_SPINLOCK(lock);
	int retries = 0;

	if (num_online_cpus() < 2)
		return 0;

	/* Can deadlock when called with interrupts disabled */
	WARN_ON(irqs_disabled());

	/* can also deadlock if IPIs are disabled */
	WARN_ON((get_eiem() & (1UL<<(CPU_IRQ_MAX - IPI_IRQ))) == 0);

	
	data.func = func;
	data.info = info;
	data.wait = wait;
	atomic_set(&data.unstarted_count, num_online_cpus() - 1);
	atomic_set(&data.unfinished_count, num_online_cpus() - 1);

	if (retry) {
		spin_lock (&lock);
		while (smp_call_function_data != 0)
			barrier();
	}
	else {
		spin_lock (&lock);
		if (smp_call_function_data) {
			spin_unlock (&lock);
			return -EBUSY;
		}
	}

	smp_call_function_data = &data;
	spin_unlock (&lock);
	
	/*  Send a message to all other CPUs and wait for them to respond  */
	send_IPI_allbutself(IPI_CALL_FUNC);

 retry:
	/*  Wait for response  */
	timeout = jiffies + HZ;
	while ( (atomic_read (&data.unstarted_count) > 0) &&
		time_before (jiffies, timeout) )
		barrier ();

	if (atomic_read (&data.unstarted_count) > 0) {
		printk(KERN_CRIT "SMP CALL FUNCTION TIMED OUT! (cpu=%d), try %d\n",
		      smp_processor_id(), ++retries);
		goto retry;
	}
	/* We either got one or timed out. Release the lock */

	mb();
	smp_call_function_data = NULL;

	while (wait && atomic_read (&data.unfinished_count) > 0)
			barrier ();

	return 0;
}

EXPORT_SYMBOL(smp_call_function);

/*
 * Flush all other CPU's tlb and then mine.  Do this with on_each_cpu()
 * as we want to ensure all TLB's flushed before proceeding.
 */

void
smp_flush_tlb_all(void)
{
	on_each_cpu(flush_tlb_all_local, NULL, 1, 1);
}


void 
smp_do_timer(struct pt_regs *regs)
{
	int cpu = smp_processor_id();
	struct cpuinfo_parisc *data = &cpu_data[cpu];

        if (!--data->prof_counter) {
		data->prof_counter = data->prof_multiplier;
		update_process_times(user_mode(regs));
	}
}

/*
 * Called by secondaries to update state and initialize CPU registers.
 */
static void __init
smp_cpu_init(int cpunum)
{
	extern int init_per_cpu(int);  /* arch/parisc/kernel/processor.c */
	extern void init_IRQ(void);    /* arch/parisc/kernel/irq.c */
	extern void start_cpu_itimer(void); /* arch/parisc/kernel/time.c */

	/* Set modes and Enable floating point coprocessor */
	(void) init_per_cpu(cpunum);

	disable_sr_hashing();

	mb();

	/* Well, support 2.4 linux scheme as well. */
	if (cpu_test_and_set(cpunum, cpu_online_map))
	{
		extern void machine_halt(void); /* arch/parisc.../process.c */

		printk(KERN_CRIT "CPU#%d already initialized!\n", cpunum);
		machine_halt();
	}  

	/* Initialise the idle task for this CPU */
	atomic_inc(&init_mm.mm_count);
	current->active_mm = &init_mm;
	if(current->mm)
		BUG();
	enter_lazy_tlb(&init_mm, current);

	init_IRQ();   /* make sure no IRQ's are enabled or pending */
	start_cpu_itimer();
}


/*
 * Slaves start using C here. Indirectly called from smp_slave_stext.
 * Do what start_kernel() and main() do for boot strap processor (aka monarch)
 */
void __init smp_callin(void)
{
	int slave_id = cpu_now_booting;
#if 0
	void *istack;
#endif

	smp_cpu_init(slave_id);
	preempt_disable();

#if 0	/* NOT WORKING YET - see entry.S */
	istack = (void *)__get_free_pages(GFP_KERNEL,ISTACK_ORDER);
	if (istack == NULL) {
	    printk(KERN_CRIT "Failed to allocate interrupt stack for cpu %d\n",slave_id);
	    BUG();
	}
	mtctl(istack,31);
#endif

	flush_cache_all_local(); /* start with known state */
	flush_tlb_all_local(NULL);

	local_irq_enable();  /* Interrupts have been off until now */

	cpu_idle();      /* Wait for timer to schedule some work */

	/* NOTREACHED */
	panic("smp_callin() AAAAaaaaahhhh....\n");
}

/*
 * Bring one cpu online.
 */
int __init smp_boot_one_cpu(int cpuid)
{
	struct task_struct *idle;
	long timeout;

	/* 
	 * Create an idle task for this CPU.  Note the address wed* give 
	 * to kernel_thread is irrelevant -- it's going to start
	 * where OS_BOOT_RENDEVZ vector in SAL says to start.  But
	 * this gets all the other task-y sort of data structures set
	 * up like we wish.   We need to pull the just created idle task 
	 * off the run queue and stuff it into the init_tasks[] array.  
	 * Sheesh . . .
	 */

	idle = fork_idle(cpuid);
	if (IS_ERR(idle))
		panic("SMP: fork failed for CPU:%d", cpuid);

	task_thread_info(idle)->cpu = cpuid;

	/* Let _start know what logical CPU we're booting
	** (offset into init_tasks[],cpu_data[])
	*/
	cpu_now_booting = cpuid;

	/* 
	** boot strap code needs to know the task address since
	** it also contains the process stack.
	*/
	smp_init_current_idle_task = idle ;
	mb();

	printk("Releasing cpu %d now, hpa=%lx\n", cpuid, cpu_data[cpuid].hpa);

	/*
	** This gets PDC to release the CPU from a very tight loop.
	**
	** From the PA-RISC 2.0 Firmware Architecture Reference Specification:
	** "The MEM_RENDEZ vector specifies the location of OS_RENDEZ which 
	** is executed after receiving the rendezvous signal (an interrupt to 
	** EIR{0}). MEM_RENDEZ is valid only when it is nonzero and the 
	** contents of memory are valid."
	*/
	gsc_writel(TIMER_IRQ - CPU_IRQ_BASE, cpu_data[cpuid].hpa);
	mb();

	/* 
	 * OK, wait a bit for that CPU to finish staggering about. 
	 * Slave will set a bit when it reaches smp_cpu_init().
	 * Once the "monarch CPU" sees the bit change, it can move on.
	 */
	for (timeout = 0; timeout < 10000; timeout++) {
		if(cpu_online(cpuid)) {
			/* Which implies Slave has started up */
			cpu_now_booting = 0;
			smp_init_current_idle_task = NULL;
			goto alive ;
		}
		udelay(100);
		barrier();
	}

	put_task_struct(idle);
	idle = NULL;

	printk(KERN_CRIT "SMP: CPU:%d is stuck.\n", cpuid);
	return -1;

alive:
	/* Remember the Slave data */
#if (kDEBUG>=100)
	printk(KERN_DEBUG "SMP: CPU:%d came alive after %ld _us\n",
		cpuid, timeout * 100);
#endif /* kDEBUG */
#ifdef ENTRY_SYS_CPUS
	cpu_data[cpuid].state = STATE_RUNNING;
#endif
	return 0;
}

void __devinit smp_prepare_boot_cpu(void)
{
	int bootstrap_processor=cpu_data[0].cpuid;	/* CPU ID of BSP */

#ifdef ENTRY_SYS_CPUS
	cpu_data[0].state = STATE_RUNNING;
#endif

	/* Setup BSP mappings */
	printk("SMP: bootstrap CPU ID is %d\n",bootstrap_processor);

	cpu_set(bootstrap_processor, cpu_online_map);
	cpu_set(bootstrap_processor, cpu_present_map);
}


/*
** inventory.c:do_inventory() hasn't yet been run and thus we
** don't 'discover' the additional CPU's until later.
*/
void __init smp_prepare_cpus(unsigned int max_cpus)
{
	cpus_clear(cpu_present_map);
	cpu_set(0, cpu_present_map);

	parisc_max_cpus = max_cpus;
	if (!max_cpus)
		printk(KERN_INFO "SMP mode deactivated.\n");
}


void smp_cpus_done(unsigned int cpu_max)
{
	return;
}


int __devinit __cpu_up(unsigned int cpu)
{
	if (cpu != 0 && cpu < parisc_max_cpus)
		smp_boot_one_cpu(cpu);

	return cpu_online(cpu) ? 0 : -ENOSYS;
}


#ifdef ENTRY_SYS_CPUS
/* Code goes along with:
**    entry.s:        ENTRY_NAME(sys_cpus)   / * 215, for cpu stat * /
*/
int sys_cpus(int argc, char **argv)
{
	int i,j=0;
	extern int current_pid(int cpu);

	if( argc > 2 ) {
		printk("sys_cpus:Only one argument supported\n");
		return (-1);
	}
	if ( argc == 1 ){
	
#ifdef DUMP_MORE_STATE
		for_each_online_cpu(i) {
			int cpus_per_line = 4;

			if (j++ % cpus_per_line)
				printk(" %3d",i);
			else
				printk("\n %3d",i);
		}
		printk("\n"); 
#else
	    	printk("\n 0\n"); 
#endif
	} else if((argc==2) && !(strcmp(argv[1],"-l"))) {
		printk("\nCPUSTATE  TASK CPUNUM CPUID HARDCPU(HPA)\n");
#ifdef DUMP_MORE_STATE
		for_each_online_cpu(i) {
			if (cpu_data[i].cpuid != NO_PROC_ID) {
				switch(cpu_data[i].state) {
					case STATE_RENDEZVOUS:
						printk("RENDEZVS ");
						break;
					case STATE_RUNNING:
						printk((current_pid(i)!=0) ? "RUNNING  " : "IDLING   ");
						break;
					case STATE_STOPPED:
						printk("STOPPED  ");
						break;
					case STATE_HALTED:
						printk("HALTED   ");
						break;
					default:
						printk("%08x?", cpu_data[i].state);
						break;
				}
				if(cpu_online(i)) {
					printk(" %4d",current_pid(i));
				}	
				printk(" %6d",cpu_number_map(i));
				printk(" %5d",i);
				printk(" 0x%lx\n",cpu_data[i].hpa);
			}	
		}
#else
		printk("\n%s  %4d      0     0 --------",
			(current->pid)?"RUNNING ": "IDLING  ",current->pid); 
#endif
	} else if ((argc==2) && !(strcmp(argv[1],"-s"))) { 
#ifdef DUMP_MORE_STATE
     		printk("\nCPUSTATE   CPUID\n");
		for_each_online_cpu(i) {
			if (cpu_data[i].cpuid != NO_PROC_ID) {
				switch(cpu_data[i].state) {
					case STATE_RENDEZVOUS:
						printk("RENDEZVS");break;
					case STATE_RUNNING:
						printk((current_pid(i)!=0) ? "RUNNING " : "IDLING");
						break;
					case STATE_STOPPED:
						printk("STOPPED ");break;
					case STATE_HALTED:
						printk("HALTED  ");break;
					default:
				}
				printk("  %5d\n",i);
			}	
		}
#else
		printk("\n%s    CPU0",(current->pid==0)?"RUNNING ":"IDLING  "); 
#endif
	} else {
		printk("sys_cpus:Unknown request\n");
		return (-1);
	}
	return 0;
}
#endif /* ENTRY_SYS_CPUS */

#ifdef CONFIG_PROC_FS
int __init
setup_profiling_timer(unsigned int multiplier)
{
	return -EINVAL;
}
#endif
Commit	Line	Data
1da177e4 LT	1	/*
	2	** SMP Support
	3	**
	4	** Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
	5	** Copyright (C) 1999 David Mosberger-Tang <davidm@hpl.hp.com>
	6	** Copyright (C) 2001,2004 Grant Grundler <grundler@parisc-linux.org>
	7	**
	8	** Lots of stuff stolen from arch/alpha/kernel/smp.c
	9	** ...and then parisc stole from arch/ia64/kernel/smp.c. Thanks David! :^)
	10	**
	11	** Thanks to John Curry and Ullas Ponnadi. I learned alot from their work.
	12	** -grant (1/12/2001)
	13	**
	14	** This program is free software; you can redistribute it and/or modify
	15	** it under the terms of the GNU General Public License as published by
	16	** the Free Software Foundation; either version 2 of the License, or
	17	** (at your option) any later version.
	18	*/
	19	#undef ENTRY_SYS_CPUS /* syscall support for iCOD-like functionality */
	20
1da177e4 LT	21
	22	#include <linux/types.h>
	23	#include <linux/spinlock.h>
	24	#include <linux/slab.h>
	25
	26	#include <linux/kernel.h>
	27	#include <linux/module.h>
	28	#include <linux/sched.h>
	29	#include <linux/init.h>
	30	#include <linux/interrupt.h>
	31	#include <linux/smp.h>
	32	#include <linux/kernel_stat.h>
	33	#include <linux/mm.h>
	34	#include <linux/delay.h>
	35	#include <linux/bitops.h>
	36
	37	#include <asm/system.h>
	38	#include <asm/atomic.h>
	39	#include <asm/current.h>
	40	#include <asm/delay.h>
1b2425e3	41	#include <asm/tlbflush.h>
1da177e4 LT	42
	43	#include <asm/io.h>
	44	#include <asm/irq.h> /* for CPU_IRQ_REGION and friends */
	45	#include <asm/mmu_context.h>
	46	#include <asm/page.h>
	47	#include <asm/pgtable.h>
	48	#include <asm/pgalloc.h>
	49	#include <asm/processor.h>
	50	#include <asm/ptrace.h>
	51	#include <asm/unistd.h>
	52	#include <asm/cacheflush.h>
	53
	54	#define kDEBUG 0
	55
	56	DEFINE_SPINLOCK(smp_lock);
	57
	58	volatile struct task_struct *smp_init_current_idle_task;
	59
8039de10	60	static volatile int cpu_now_booting __read_mostly = 0; /* track which CPU is booting */
1da177e4	61
8039de10	62	static int parisc_max_cpus __read_mostly = 1;
1da177e4 LT	63
	64	/* online cpus are ones that we've managed to bring up completely
	65	* possible cpus are all valid cpu
	66	* present cpus are all detected cpu
	67	*
	68	* On startup we bring up the "possible" cpus. Since we discover
	69	* CPUs later, we add them as hotplug, so the possible cpu mask is
	70	* empty in the beginning.
	71	*/
	72
8039de10 HD	73	cpumask_t cpu_online_map __read_mostly = CPU_MASK_NONE; /* Bitmap of online CPUs */
8039de10 HD	74	cpumask_t cpu_possible_map __read_mostly = CPU_MASK_ALL; /* Bitmap of Present CPUs */
1da177e4 LT	75
	76	EXPORT_SYMBOL(cpu_online_map);
	77	EXPORT_SYMBOL(cpu_possible_map);
	78
	79
	80	struct smp_call_struct {
	81	void (func) (void info);
	82	void *info;
	83	long wait;
	84	atomic_t unstarted_count;
	85	atomic_t unfinished_count;
	86	};
	87	static volatile struct smp_call_struct *smp_call_function_data;
	88
	89	enum ipi_message_type {
	90	IPI_NOP=0,
	91	IPI_RESCHEDULE=1,
	92	IPI_CALL_FUNC,
	93	IPI_CPU_START,
	94	IPI_CPU_STOP,
	95	IPI_CPU_TEST
	96	};
	97
	98
	99	/********** SMP inter processor interrupt and communication routines */
	100
	101	#undef PER_CPU_IRQ_REGION
	102	#ifdef PER_CPU_IRQ_REGION
	103	/* XXX REVISIT Ignore for now.
	104	** May need this "hook" to register IPI handler
	105	** once we have perCPU ExtIntr switch tables.
	106	*/
	107	static void
	108	ipi_init(int cpuid)
	109	{
	110
	111	/* If CPU is present ... */
	112	#ifdef ENTRY_SYS_CPUS
	113	/* and running (not stopped) ... */
	114	#error iCOD support wants state checked here.
	115	#endif
	116
	117	#error verify IRQ_OFFSET(IPI_IRQ) is ipi_interrupt() in new IRQ region
	118
	119	if(cpu_online(cpuid) )
	120	{
	121	switch_to_idle_task(current);
	122	}
	123
	124	return;
	125	}
	126	#endif
	127
	128
	129	/*
	130	** Yoink this CPU from the runnable list...
	131	**
	132	*/
	133	static void
	134	halt_processor(void)
	135	{
	136	#ifdef ENTRY_SYS_CPUS
	137	#error halt_processor() needs rework
	138	/*
139	** o migrate I/O interrupts off this CPU.
140	** o leave IPI enabled - __cli() will disable IPI.
141	** o leave CPU in online map - just change the state
142	*/
143	cpu_data[this_cpu].state = STATE_STOPPED;
144	mark_bh(IPI_BH);
145	#else
146	/* REVISIT : redirect I/O Interrupts to another CPU? */
147	/* REVISIT : does PM know this CPU isn't available? */
148	cpu_clear(smp_processor_id(), cpu_online_map);
149	local_irq_disable();
150	for (;;)
151	;
152	#endif
153	}
154
155
156	irqreturn_t
157	ipi_interrupt(int irq, void dev_id, struct pt_regs regs)
158	{
159	int this_cpu = smp_processor_id();
160	struct cpuinfo_parisc *p = &cpu_data[this_cpu];
161	unsigned long ops;
162	unsigned long flags;
163
164	/* Count this now; we may make a call that never returns. */
165	p->ipi_count++;
166
167	mb(); /* Order interrupt and bit testing. */
168
169	for (;;) {
170	spin_lock_irqsave(&(p->lock),flags);
171	ops = p->pending_ipi;
172	p->pending_ipi = 0;
173	spin_unlock_irqrestore(&(p->lock),flags);
174
175	mb(); /* Order bit clearing and data access. */
176
177	if (!ops)
178	break;
179
180	while (ops) {
181	unsigned long which = ffz(~ops);
182
d911aed8 JB	183	ops &= ~(1 << which);
d911aed8 JB	184
1da177e4	185	switch (which) {
d911aed8 JB	186	case IPI_NOP:
	187	#if (kDEBUG>=100)
	188	printk(KERN_DEBUG "CPU%d IPI_NOP\n",this_cpu);
	189	#endif /* kDEBUG */
	190	break;
	191
1da177e4 LT	192	case IPI_RESCHEDULE:
	193	#if (kDEBUG>=100)
	194	printk(KERN_DEBUG "CPU%d IPI_RESCHEDULE\n",this_cpu);
	195	#endif /* kDEBUG */
1da177e4 LT	196	/*
	197	* Reschedule callback. Everything to be
	198	* done is done by the interrupt return path.
	199	*/
	200	break;
	201
	202	case IPI_CALL_FUNC:
	203	#if (kDEBUG>=100)
	204	printk(KERN_DEBUG "CPU%d IPI_CALL_FUNC\n",this_cpu);
	205	#endif /* kDEBUG */
1da177e4 LT	206	{
	207	volatile struct smp_call_struct *data;
	208	void (func)(void info);
	209	void *info;
	210	int wait;
	211
	212	data = smp_call_function_data;
	213	func = data->func;
	214	info = data->info;
	215	wait = data->wait;
	216
	217	mb();
	218	atomic_dec ((atomic_t *)&data->unstarted_count);
	219
	220	/* At this point, *data can't
	221	* be relied upon.
	222	*/
	223
	224	(*func)(info);
	225
	226	/* Notify the sending CPU that the
	227	* task is done.
	228	*/
	229	mb();
	230	if (wait)
	231	atomic_dec ((atomic_t *)&data->unfinished_count);
	232	}
	233	break;
	234
	235	case IPI_CPU_START:
	236	#if (kDEBUG>=100)
	237	printk(KERN_DEBUG "CPU%d IPI_CPU_START\n",this_cpu);
	238	#endif /* kDEBUG */
1da177e4 LT	239	#ifdef ENTRY_SYS_CPUS
	240	p->state = STATE_RUNNING;
	241	#endif
	242	break;
	243
	244	case IPI_CPU_STOP:
	245	#if (kDEBUG>=100)
	246	printk(KERN_DEBUG "CPU%d IPI_CPU_STOP\n",this_cpu);
	247	#endif /* kDEBUG */
1da177e4 LT	248	#ifdef ENTRY_SYS_CPUS
	249	#else
	250	halt_processor();
	251	#endif
	252	break;
	253
	254	case IPI_CPU_TEST:
	255	#if (kDEBUG>=100)
	256	printk(KERN_DEBUG "CPU%d is alive!\n",this_cpu);
	257	#endif /* kDEBUG */
1da177e4 LT	258	break;
	259
	260	default:
	261	printk(KERN_CRIT "Unknown IPI num on CPU%d: %lu\n",
	262	this_cpu, which);
1da177e4 LT	263	return IRQ_NONE;
	264	} /* Switch */
	265	} /* while (ops) */
	266	}
	267	return IRQ_HANDLED;
	268	}
	269
	270
	271	static inline void
	272	ipi_send(int cpu, enum ipi_message_type op)
	273	{
	274	struct cpuinfo_parisc *p = &cpu_data[cpu];
	275	unsigned long flags;
	276
	277	spin_lock_irqsave(&(p->lock),flags);
	278	p->pending_ipi \|= 1 << op;
	279	gsc_writel(IPI_IRQ - CPU_IRQ_BASE, cpu_data[cpu].hpa);
	280	spin_unlock_irqrestore(&(p->lock),flags);
	281	}
	282
	283
	284	static inline void
	285	send_IPI_single(int dest_cpu, enum ipi_message_type op)
	286	{
	287	if (dest_cpu == NO_PROC_ID) {
	288	BUG();
	289	return;
	290	}
	291
	292	ipi_send(dest_cpu, op);
	293	}
	294
	295	static inline void
	296	send_IPI_allbutself(enum ipi_message_type op)
	297	{
	298	int i;
	299
394e3902 AM	300	for_each_online_cpu(i) {
394e3902 AM	301	if (i != smp_processor_id())
1da177e4 LT	302	send_IPI_single(i, op);
	303	}
	304	}
	305
	306
	307	inline void
	308	smp_send_stop(void) { send_IPI_allbutself(IPI_CPU_STOP); }
	309
	310	static inline void
	311	smp_send_start(void) { send_IPI_allbutself(IPI_CPU_START); }
	312
	313	void
	314	smp_send_reschedule(int cpu) { send_IPI_single(cpu, IPI_RESCHEDULE); }
	315
d911aed8 JB	316	void
	317	smp_send_all_nop(void)
	318	{
	319	send_IPI_allbutself(IPI_NOP);
	320	}
	321
1da177e4 LT	322
	323	/**
	324	* Run a function on all other CPUs.
	325	* <func> The function to run. This must be fast and non-blocking.
	326	* <info> An arbitrary pointer to pass to the function.
	327	* <retry> If true, keep retrying until ready.
	328	* <wait> If true, wait until function has completed on other CPUs.
	329	* [RETURNS] 0 on success, else a negative status code.
	330	*
	331	* Does not return until remote CPUs are nearly ready to execute <func>
	332	* or have executed.
	333	*/
	334
	335	int
	336	smp_call_function (void (func) (void info), void *info, int retry, int wait)
	337	{
	338	struct smp_call_struct data;
	339	unsigned long timeout;
	340	static DEFINE_SPINLOCK(lock);
	341	int retries = 0;
	342
	343	if (num_online_cpus() < 2)
	344	return 0;
	345
	346	/* Can deadlock when called with interrupts disabled */
	347	WARN_ON(irqs_disabled());
9a8b4584 JB	348
	349	/* can also deadlock if IPIs are disabled */
	350	WARN_ON((get_eiem() & (1UL<<(CPU_IRQ_MAX - IPI_IRQ))) == 0);
	351
1da177e4 LT	352
	353	data.func = func;
	354	data.info = info;
	355	data.wait = wait;
	356	atomic_set(&data.unstarted_count, num_online_cpus() - 1);
	357	atomic_set(&data.unfinished_count, num_online_cpus() - 1);
	358
	359	if (retry) {
	360	spin_lock (&lock);
	361	while (smp_call_function_data != 0)
	362	barrier();
	363	}
	364	else {
	365	spin_lock (&lock);
	366	if (smp_call_function_data) {
	367	spin_unlock (&lock);
	368	return -EBUSY;
	369	}
	370	}
	371
	372	smp_call_function_data = &data;
	373	spin_unlock (&lock);
	374
	375	/* Send a message to all other CPUs and wait for them to respond */
	376	send_IPI_allbutself(IPI_CALL_FUNC);
	377
	378	retry:
	379	/* Wait for response */
	380	timeout = jiffies + HZ;
	381	while ( (atomic_read (&data.unstarted_count) > 0) &&
	382	time_before (jiffies, timeout) )
	383	barrier ();
	384
	385	if (atomic_read (&data.unstarted_count) > 0) {
	386	printk(KERN_CRIT "SMP CALL FUNCTION TIMED OUT! (cpu=%d), try %d\n",
	387	smp_processor_id(), ++retries);
	388	goto retry;
	389	}
	390	/* We either got one or timed out. Release the lock */
	391
	392	mb();
	393	smp_call_function_data = NULL;
	394
	395	while (wait && atomic_read (&data.unfinished_count) > 0)
	396	barrier ();
	397
	398	return 0;
	399	}
	400
	401	EXPORT_SYMBOL(smp_call_function);
	402
	403	/*
	404	* Flush all other CPU's tlb and then mine. Do this with on_each_cpu()
	405	* as we want to ensure all TLB's flushed before proceeding.
	406	*/
	407
1da177e4 LT	408	void
	409	smp_flush_tlb_all(void)
	410	{
1b2425e3	411	on_each_cpu(flush_tlb_all_local, NULL, 1, 1);
1da177e4 LT	412	}
	413
	414
	415	void
	416	smp_do_timer(struct pt_regs *regs)
	417	{
	418	int cpu = smp_processor_id();
	419	struct cpuinfo_parisc *data = &cpu_data[cpu];
	420
	421	if (!--data->prof_counter) {
	422	data->prof_counter = data->prof_multiplier;
	423	update_process_times(user_mode(regs));
	424	}
	425	}
	426
	427	/*
	428	* Called by secondaries to update state and initialize CPU registers.
	429	*/
	430	static void __init
	431	smp_cpu_init(int cpunum)
	432	{
56f335c8	433	extern int init_per_cpu(int); /* arch/parisc/kernel/processor.c */
1da177e4	434	extern void init_IRQ(void); /* arch/parisc/kernel/irq.c */
56f335c8	435	extern void start_cpu_itimer(void); /* arch/parisc/kernel/time.c */
1da177e4 LT	436
	437	/* Set modes and Enable floating point coprocessor */
	438	(void) init_per_cpu(cpunum);
	439
	440	disable_sr_hashing();
	441
	442	mb();
	443
	444	/* Well, support 2.4 linux scheme as well. */
	445	if (cpu_test_and_set(cpunum, cpu_online_map))
	446	{
	447	extern void machine_halt(void); /* arch/parisc.../process.c */
	448
	449	printk(KERN_CRIT "CPU#%d already initialized!\n", cpunum);
	450	machine_halt();
	451	}
	452
	453	/* Initialise the idle task for this CPU */
	454	atomic_inc(&init_mm.mm_count);
	455	current->active_mm = &init_mm;
	456	if(current->mm)
	457	BUG();
	458	enter_lazy_tlb(&init_mm, current);
	459
	460	init_IRQ(); /* make sure no IRQ's are enabled or pending */
56f335c8	461	start_cpu_itimer();
1da177e4 LT	462	}
	463
	464
	465	/*
	466	* Slaves start using C here. Indirectly called from smp_slave_stext.
	467	* Do what start_kernel() and main() do for boot strap processor (aka monarch)
	468	*/
	469	void __init smp_callin(void)
	470	{
	471	int slave_id = cpu_now_booting;
	472	#if 0
	473	void *istack;
	474	#endif
	475
	476	smp_cpu_init(slave_id);
5bfb5d69	477	preempt_disable();
1da177e4 LT	478
	479	#if 0 /* NOT WORKING YET - see entry.S */
	480	istack = (void *)__get_free_pages(GFP_KERNEL,ISTACK_ORDER);
	481	if (istack == NULL) {
	482	printk(KERN_CRIT "Failed to allocate interrupt stack for cpu %d\n",slave_id);
	483	BUG();
	484	}
	485	mtctl(istack,31);
	486	#endif
	487
	488	flush_cache_all_local(); /* start with known state */
1b2425e3	489	flush_tlb_all_local(NULL);
1da177e4 LT	490
	491	local_irq_enable(); /* Interrupts have been off until now */
	492
	493	cpu_idle(); /* Wait for timer to schedule some work */
	494
	495	/* NOTREACHED */
	496	panic("smp_callin() AAAAaaaaahhhh....\n");
	497	}
	498
	499	/*
	500	* Bring one cpu online.
	501	*/
	502	int __init smp_boot_one_cpu(int cpuid)
	503	{
	504	struct task_struct *idle;
	505	long timeout;
	506
	507	/*
	508	* Create an idle task for this CPU. Note the address wed* give
	509	* to kernel_thread is irrelevant -- it's going to start
	510	* where OS_BOOT_RENDEVZ vector in SAL says to start. But
	511	* this gets all the other task-y sort of data structures set
	512	* up like we wish. We need to pull the just created idle task
	513	* off the run queue and stuff it into the init_tasks[] array.
	514	* Sheesh . . .
	515	*/
	516
	517	idle = fork_idle(cpuid);
	518	if (IS_ERR(idle))
	519	panic("SMP: fork failed for CPU:%d", cpuid);
	520
40f1f0de	521	task_thread_info(idle)->cpu = cpuid;
1da177e4 LT	522
	523	/* Let _start know what logical CPU we're booting
	524	** (offset into init_tasks[],cpu_data[])
	525	*/
	526	cpu_now_booting = cpuid;
	527
	528	/*
	529	** boot strap code needs to know the task address since
	530	** it also contains the process stack.
	531	*/
	532	smp_init_current_idle_task = idle ;
	533	mb();
	534
	535	printk("Releasing cpu %d now, hpa=%lx\n", cpuid, cpu_data[cpuid].hpa);
	536
	537	/*
	538	** This gets PDC to release the CPU from a very tight loop.
	539	**
	540	** From the PA-RISC 2.0 Firmware Architecture Reference Specification:
	541	** "The MEM_RENDEZ vector specifies the location of OS_RENDEZ which
	542	** is executed after receiving the rendezvous signal (an interrupt to
	543	** EIR{0}). MEM_RENDEZ is valid only when it is nonzero and the
	544	** contents of memory are valid."
	545	*/
	546	gsc_writel(TIMER_IRQ - CPU_IRQ_BASE, cpu_data[cpuid].hpa);
	547	mb();
	548
	549	/*
	550	* OK, wait a bit for that CPU to finish staggering about.
	551	* Slave will set a bit when it reaches smp_cpu_init().
	552	* Once the "monarch CPU" sees the bit change, it can move on.
	553	*/
	554	for (timeout = 0; timeout < 10000; timeout++) {
	555	if(cpu_online(cpuid)) {
	556	/* Which implies Slave has started up */
	557	cpu_now_booting = 0;
	558	smp_init_current_idle_task = NULL;
	559	goto alive ;
	560	}
	561	udelay(100);
	562	barrier();
	563	}
	564
	565	put_task_struct(idle);
	566	idle = NULL;
	567
	568	printk(KERN_CRIT "SMP: CPU:%d is stuck.\n", cpuid);
	569	return -1;
	570
	571	alive:
	572	/* Remember the Slave data */
	573	#if (kDEBUG>=100)
	574	printk(KERN_DEBUG "SMP: CPU:%d came alive after %ld _us\n",
	575	cpuid, timeout * 100);
	576	#endif /* kDEBUG */
	577	#ifdef ENTRY_SYS_CPUS
	578	cpu_data[cpuid].state = STATE_RUNNING;
	579	#endif
	580	return 0;
	581	}
	582
	583	void __devinit smp_prepare_boot_cpu(void)
	584	{
	585	int bootstrap_processor=cpu_data[0].cpuid; /* CPU ID of BSP */
586
587	#ifdef ENTRY_SYS_CPUS
588	cpu_data[0].state = STATE_RUNNING;
589	#endif
590
591	/* Setup BSP mappings */
592	printk("SMP: bootstrap CPU ID is %d\n",bootstrap_processor);
593
594	cpu_set(bootstrap_processor, cpu_online_map);
595	cpu_set(bootstrap_processor, cpu_present_map);
596	}
597
598
599
600	/*
601	** inventory.c:do_inventory() hasn't yet been run and thus we
602	** don't 'discover' the additional CPU's until later.
603	*/
604	void __init smp_prepare_cpus(unsigned int max_cpus)
605	{
606	cpus_clear(cpu_present_map);
607	cpu_set(0, cpu_present_map);
608
609	parisc_max_cpus = max_cpus;
610	if (!max_cpus)
611	printk(KERN_INFO "SMP mode deactivated.\n");
612	}
613
614
615	void smp_cpus_done(unsigned int cpu_max)
616	{
617	return;
618	}
619
620
621	int __devinit __cpu_up(unsigned int cpu)
622	{
623	if (cpu != 0 && cpu < parisc_max_cpus)
624	smp_boot_one_cpu(cpu);
625
626	return cpu_online(cpu) ? 0 : -ENOSYS;
627	}
628
629
630
631	#ifdef ENTRY_SYS_CPUS
632	/* Code goes along with:
633	** entry.s: ENTRY_NAME(sys_cpus) / * 215, for cpu stat * /
634	*/
635	int sys_cpus(int argc, char **argv)
636	{
637	int i,j=0;
638	extern int current_pid(int cpu);
639
640	if( argc > 2 ) {
641	printk("sys_cpus:Only one argument supported\n");
642	return (-1);
643	}
644	if ( argc == 1 ){
645
646	#ifdef DUMP_MORE_STATE
394e3902	647	for_each_online_cpu(i) {
1da177e4	648	int cpus_per_line = 4;
394e3902 AM	649
	650	if (j++ % cpus_per_line)
	651	printk(" %3d",i);
	652	else
	653	printk("\n %3d",i);
1da177e4 LT	654	}
	655	printk("\n");
	656	#else
	657	printk("\n 0\n");
	658	#endif
	659	} else if((argc==2) && !(strcmp(argv[1],"-l"))) {
	660	printk("\nCPUSTATE TASK CPUNUM CPUID HARDCPU(HPA)\n");
	661	#ifdef DUMP_MORE_STATE
394e3902	662	for_each_online_cpu(i) {
1da177e4 LT	663	if (cpu_data[i].cpuid != NO_PROC_ID) {
	664	switch(cpu_data[i].state) {
	665	case STATE_RENDEZVOUS:
	666	printk("RENDEZVS ");
	667	break;
	668	case STATE_RUNNING:
	669	printk((current_pid(i)!=0) ? "RUNNING " : "IDLING ");
	670	break;
	671	case STATE_STOPPED:
	672	printk("STOPPED ");
	673	break;
	674	case STATE_HALTED:
	675	printk("HALTED ");
	676	break;
	677	default:
	678	printk("%08x?", cpu_data[i].state);
	679	break;
	680	}
	681	if(cpu_online(i)) {
	682	printk(" %4d",current_pid(i));
	683	}
	684	printk(" %6d",cpu_number_map(i));
	685	printk(" %5d",i);
	686	printk(" 0x%lx\n",cpu_data[i].hpa);
	687	}
	688	}
	689	#else
	690	printk("\n%s %4d 0 0 --------",
	691	(current->pid)?"RUNNING ": "IDLING ",current->pid);
	692	#endif
	693	} else if ((argc==2) && !(strcmp(argv[1],"-s"))) {
	694	#ifdef DUMP_MORE_STATE
	695	printk("\nCPUSTATE CPUID\n");
394e3902	696	for_each_online_cpu(i) {
1da177e4 LT	697	if (cpu_data[i].cpuid != NO_PROC_ID) {
	698	switch(cpu_data[i].state) {
	699	case STATE_RENDEZVOUS:
	700	printk("RENDEZVS");break;
	701	case STATE_RUNNING:
	702	printk((current_pid(i)!=0) ? "RUNNING " : "IDLING");
	703	break;
	704	case STATE_STOPPED:
	705	printk("STOPPED ");break;
	706	case STATE_HALTED:
	707	printk("HALTED ");break;
	708	default:
	709	}
	710	printk(" %5d\n",i);
	711	}
	712	}
	713	#else
	714	printk("\n%s CPU0",(current->pid==0)?"RUNNING ":"IDLING ");
	715	#endif
	716	} else {
	717	printk("sys_cpus:Unknown request\n");
	718	return (-1);
	719	}
	720	return 0;
	721	}
	722	#endif /* ENTRY_SYS_CPUS */
	723
	724	#ifdef CONFIG_PROC_FS
	725	int __init
	726	setup_profiling_timer(unsigned int multiplier)
	727	{
	728	return -EINVAL;
	729	}
	730	#endif