Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 399 insertions, 0 deletions

diff --git a/arch/ppc/kernel/smp.c b/arch/ppc/kernel/smp.c
new file mode 100644
index 000000000000..e70b587b9e51
--- /dev/null
+++ b/arch/ppc/kernel/smp.c
@@ -0,0 +1,399 @@
+/*
+ * Smp support for ppc.
+ *
+ * Written by Cort Dougan (cort@cs.nmt.edu) borrowing a great
+ * deal of code from the sparc and intel versions.
+ *
+ * Copyright (C) 1999 Cort Dougan <cort@cs.nmt.edu>
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/interrupt.h>
+#include <linux/kernel_stat.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/cache.h>
+
+#include <asm/ptrace.h>
+#include <asm/atomic.h>
+#include <asm/irq.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/io.h>
+#include <asm/prom.h>
+#include <asm/smp.h>
+#include <asm/residual.h>
+#include <asm/time.h>
+#include <asm/thread_info.h>
+#include <asm/tlbflush.h>
+#include <asm/xmon.h>
+
+volatile int smp_commenced;
+int smp_tb_synchronized;
+struct cpuinfo_PPC cpu_data[NR_CPUS];
+struct klock_info_struct klock_info = { KLOCK_CLEAR, 0 };
+atomic_t ipi_recv;
+atomic_t ipi_sent;
+cpumask_t cpu_online_map;
+cpumask_t cpu_possible_map;
+int smp_hw_index[NR_CPUS];
+struct thread_info *secondary_ti;
+
+EXPORT_SYMBOL(cpu_online_map);
+EXPORT_SYMBOL(cpu_possible_map);
+
+/* SMP operations for this machine */
+static struct smp_ops_t *smp_ops;
+
+/* all cpu mappings are 1-1 -- Cort */
+volatile unsigned long cpu_callin_map[NR_CPUS];
+
+int start_secondary(void *);
+void smp_call_function_interrupt(void);
+static int __smp_call_function(void (*func) (void *info), void *info,
+			       int wait, int target);
+
+/* Low level assembly function used to backup CPU 0 state */
+extern void __save_cpu_setup(void);
+
+/* Since OpenPIC has only 4 IPIs, we use slightly different message numbers.
+ *
+ * Make sure this matches openpic_request_IPIs in open_pic.c, or what shows up
+ * in /proc/interrupts will be wrong!!! --Troy */
+#define PPC_MSG_CALL_FUNCTION	0
+#define PPC_MSG_RESCHEDULE	1
+#define PPC_MSG_INVALIDATE_TLB	2
+#define PPC_MSG_XMON_BREAK	3
+
+static inline void
+smp_message_pass(int target, int msg, unsigned long data, int wait)
+{
+	if (smp_ops){
+		atomic_inc(&ipi_sent);
+		smp_ops->message_pass(target,msg,data,wait);
+	}
+}
+
+/*
+ * Common functions
+ */
+void smp_message_recv(int msg, struct pt_regs *regs)
+{
+	atomic_inc(&ipi_recv);
+
+	switch( msg ) {
+	case PPC_MSG_CALL_FUNCTION:
+		smp_call_function_interrupt();
+		break;
+	case PPC_MSG_RESCHEDULE:
+		set_need_resched();
+		break;
+	case PPC_MSG_INVALIDATE_TLB:
+		_tlbia();
+		break;
+#ifdef CONFIG_XMON
+	case PPC_MSG_XMON_BREAK:
+		xmon(regs);
+		break;
+#endif /* CONFIG_XMON */
+	default:
+		printk("SMP %d: smp_message_recv(): unknown msg %d\n",
+		       smp_processor_id(), msg);
+		break;
+	}
+}
+
+/*
+ * 750's don't broadcast tlb invalidates so
+ * we have to emulate that behavior.
+ *   -- Cort
+ */
+void smp_send_tlb_invalidate(int cpu)
+{
+	if ( PVR_VER(mfspr(SPRN_PVR)) == 8 )
+		smp_message_pass(MSG_ALL_BUT_SELF, PPC_MSG_INVALIDATE_TLB, 0, 0);
+}
+
+void smp_send_reschedule(int cpu)
+{
+	/*
+	 * This is only used if `cpu' is running an idle task,
+	 * so it will reschedule itself anyway...
+	 *
+	 * This isn't the case anymore since the other CPU could be
+	 * sleeping and won't reschedule until the next interrupt (such
+	 * as the timer).
+	 *  -- Cort
+	 */
+	/* This is only used if `cpu' is running an idle task,
+	   so it will reschedule itself anyway... */
+	smp_message_pass(cpu, PPC_MSG_RESCHEDULE, 0, 0);
+}
+
+#ifdef CONFIG_XMON
+void smp_send_xmon_break(int cpu)
+{
+	smp_message_pass(cpu, PPC_MSG_XMON_BREAK, 0, 0);
+}
+#endif /* CONFIG_XMON */
+
+static void stop_this_cpu(void *dummy)
+{
+	local_irq_disable();
+	while (1)
+		;
+}
+
+void smp_send_stop(void)
+{
+	smp_call_function(stop_this_cpu, NULL, 1, 0);
+}
+
+/*
+ * Structure and data for smp_call_function(). This is designed to minimise
+ * static memory requirements. It also looks cleaner.
+ * Stolen from the i386 version.
+ */
+static DEFINE_SPINLOCK(call_lock);
+
+static struct call_data_struct {
+	void (*func) (void *info);
+	void *info;
+	atomic_t started;
+	atomic_t finished;
+	int wait;
+} *call_data;
+
+/*
+ * this function sends a 'generic call function' IPI to all other CPUs
+ * in the system.
+ */
+
+int smp_call_function(void (*func) (void *info), void *info, int nonatomic,
+		      int wait)
+/*
+ * [SUMMARY] 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.
+ * <nonatomic> currently unused.
+ * <wait> If true, wait (atomically) 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 are or have executed.
+ *
+ * You must not call this function with disabled interrupts or from a
+ * hardware interrupt handler or from a bottom half handler.
+ */
+{
+	/* FIXME: get cpu lock with hotplug cpus, or change this to
+           bitmask. --RR */
+	if (num_online_cpus() <= 1)
+		return 0;
+	/* Can deadlock when called with interrupts disabled */
+	WARN_ON(irqs_disabled());
+	return __smp_call_function(func, info, wait, MSG_ALL_BUT_SELF);
+}
+
+static int __smp_call_function(void (*func) (void *info), void *info,
+			       int wait, int target)
+{
+	struct call_data_struct data;
+	int ret = -1;
+	int timeout;
+	int ncpus = 1;
+
+	if (target == MSG_ALL_BUT_SELF)
+		ncpus = num_online_cpus() - 1;
+	else if (target == MSG_ALL)
+		ncpus = num_online_cpus();
+
+	data.func = func;
+	data.info = info;
+	atomic_set(&data.started, 0);
+	data.wait = wait;
+	if (wait)
+		atomic_set(&data.finished, 0);
+
+	spin_lock(&call_lock);
+	call_data = &data;
+	/* Send a message to all other CPUs and wait for them to respond */
+	smp_message_pass(target, PPC_MSG_CALL_FUNCTION, 0, 0);
+
+	/* Wait for response */
+	timeout = 1000000;
+	while (atomic_read(&data.started) != ncpus) {
+		if (--timeout == 0) {
+			printk("smp_call_function on cpu %d: other cpus not responding (%d)\n",
+			       smp_processor_id(), atomic_read(&data.started));
+			goto out;
+		}
+		barrier();
+		udelay(1);
+	}
+
+	if (wait) {
+		timeout = 1000000;
+		while (atomic_read(&data.finished) != ncpus) {
+			if (--timeout == 0) {
+				printk("smp_call_function on cpu %d: other cpus not finishing (%d/%d)\n",
+				       smp_processor_id(), atomic_read(&data.finished), atomic_read(&data.started));
+				goto out;
+			}
+			barrier();
+			udelay(1);
+		}
+	}
+	ret = 0;
+
+ out:
+	spin_unlock(&call_lock);
+	return ret;
+}
+
+void smp_call_function_interrupt(void)
+{
+	void (*func) (void *info) = call_data->func;
+	void *info = call_data->info;
+	int wait = call_data->wait;
+
+	/*
+	 * Notify initiating CPU that I've grabbed the data and am
+	 * about to execute the function
+	 */
+	atomic_inc(&call_data->started);
+	/*
+	 * At this point the info structure may be out of scope unless wait==1
+	 */
+	(*func)(info);
+	if (wait)
+		atomic_inc(&call_data->finished);
+}
+
+static void __devinit smp_store_cpu_info(int id)
+{
+        struct cpuinfo_PPC *c = &cpu_data[id];
+
+	/* assume bogomips are same for everything */
+        c->loops_per_jiffy = loops_per_jiffy;
+        c->pvr = mfspr(SPRN_PVR);
+}
+
+void __init smp_prepare_cpus(unsigned int max_cpus)
+{
+	int num_cpus, i;
+
+	/* Fixup boot cpu */
+        smp_store_cpu_info(smp_processor_id());
+	cpu_callin_map[smp_processor_id()] = 1;
+
+	smp_ops = ppc_md.smp_ops;
+	if (smp_ops == NULL) {
+		printk("SMP not supported on this machine.\n");
+		return;
+	}
+
+	/* Probe platform for CPUs: always linear. */
+	num_cpus = smp_ops->probe();
+	for (i = 0; i < num_cpus; ++i)
+		cpu_set(i, cpu_possible_map);
+
+	/* Backup CPU 0 state */
+	__save_cpu_setup();
+
+	if (smp_ops->space_timers)
+		smp_ops->space_timers(num_cpus);
+}
+
+void __devinit smp_prepare_boot_cpu(void)
+{
+	cpu_set(smp_processor_id(), cpu_online_map);
+	cpu_set(smp_processor_id(), cpu_possible_map);
+}
+
+int __init setup_profiling_timer(unsigned int multiplier)
+{
+	return 0;
+}
+
+/* Processor coming up starts here */
+int __devinit start_secondary(void *unused)
+{
+	int cpu;
+
+	atomic_inc(&init_mm.mm_count);
+	current->active_mm = &init_mm;
+
+	cpu = smp_processor_id();
+        smp_store_cpu_info(cpu);
+	set_dec(tb_ticks_per_jiffy);
+	cpu_callin_map[cpu] = 1;
+
+	printk("CPU %i done callin...\n", cpu);
+	smp_ops->setup_cpu(cpu);
+	printk("CPU %i done setup...\n", cpu);
+	local_irq_enable();
+	smp_ops->take_timebase();
+	printk("CPU %i done timebase take...\n", cpu);
+
+	cpu_idle();
+	return 0;
+}
+
+int __cpu_up(unsigned int cpu)
+{
+	struct task_struct *p;
+	char buf[32];
+	int c;
+
+	/* create a process for the processor */
+	/* only regs.msr is actually used, and 0 is OK for it */
+	p = fork_idle(cpu);
+	if (IS_ERR(p))
+		panic("failed fork for CPU %u: %li", cpu, PTR_ERR(p));
+	secondary_ti = p->thread_info;
+	p->thread_info->cpu = cpu;
+
+	/*
+	 * There was a cache flush loop here to flush the cache
+	 * to memory for the first 8MB of RAM.  The cache flush
+	 * has been pushed into the kick_cpu function for those
+	 * platforms that need it.
+	 */
+
+	/* wake up cpu */
+	smp_ops->kick_cpu(cpu);
+	
+	/*
+	 * wait to see if the cpu made a callin (is actually up).
+	 * use this value that I found through experimentation.
+	 * -- Cort
+	 */
+	for (c = 1000; c && !cpu_callin_map[cpu]; c--)
+		udelay(100);
+
+	if (!cpu_callin_map[cpu]) {
+		sprintf(buf, "didn't find cpu %u", cpu);
+		if (ppc_md.progress) ppc_md.progress(buf, 0x360+cpu);
+		printk("Processor %u is stuck.\n", cpu);
+		return -ENOENT;
+	}
+
+	sprintf(buf, "found cpu %u", cpu);
+	if (ppc_md.progress) ppc_md.progress(buf, 0x350+cpu);
+	printk("Processor %d found.\n", cpu);
+
+	smp_ops->give_timebase();
+	cpu_set(cpu, cpu_online_map);
+	return 0;
+}
+
+void smp_cpus_done(unsigned int max_cpus)
+{
+	smp_ops->setup_cpu(0);
+}