1 files changed, 723 insertions, 0 deletions

diff --git a/arch/parisc/kernel/smp.c b/arch/parisc/kernel/smp.c
new file mode 100644
index 000000000000..bcc7e83f5142
--- /dev/null
+++ b/arch/parisc/kernel/smp.c
@@ -0,0 +1,723 @@
+/*
+** 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/autoconf.h>
+
+#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/pgalloc.h>        /* for flush_tlb_all() proto/macro */
+
+#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 = 0;        /* track which CPU is booting */
+
+static int parisc_max_cpus = 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 = CPU_MASK_NONE;       /* Bitmap of online CPUs */
+cpumask_t cpu_possible_map = 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);
+
+                        switch (which) {
+                        case IPI_RESCHEDULE:
+#if (kDEBUG>=100)
+                                printk(KERN_DEBUG "CPU%d IPI_RESCHEDULE\n",this_cpu);
+#endif /* kDEBUG */
+                                ops &= ~(1 << IPI_RESCHEDULE);
+                                /*
+                                 * 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 */
+                                ops &= ~(1 << IPI_CALL_FUNC);
+                                {
+                                        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 */
+                                ops &= ~(1 << IPI_CPU_START);
+#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 */
+                                ops &= ~(1 << IPI_CPU_STOP);
+#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 */
+                                ops &= ~(1 << IPI_CPU_TEST);
+                                break;
+
+                        default:
+                                printk(KERN_CRIT "Unknown IPI num on CPU%d: %lu\n",
+                                        this_cpu, which);
+                                ops &= ~(1 << 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 (i = 0; i < NR_CPUS; i++) {
+                if (cpu_online(i) && 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); }
+
+
+/**
+ * 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());
+        
+        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.
+ */
+
+extern void flush_tlb_all_local(void);
+
+void
+smp_flush_tlb_all(void)
+{
+        on_each_cpu((void (*)(void *))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/setup.c */
+        extern void init_IRQ(void);    /* arch/parisc/kernel/irq.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 */
+}
+
+
+/*
+ * 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);
+
+#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();
+
+        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);
+
+        idle->thread_info->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(i=0; i<NR_CPUS; i++) {
+                        int cpus_per_line = 4;
+                        if(cpu_online(i)) {
+                                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(i=0;i<NR_CPUS;i++) {
+                        if (!cpu_online(i))
+                                continue;
+                        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 (i=0;i<NR_CPUS;i++) {
+                        if (!cpu_online(i))
+                                continue;
+                        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