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!
diff --git a/arch/sparc/kernel/sun4m_smp.c b/arch/sparc/kernel/sun4m_smp.c
new file mode 100644
index 0000000..f113422
--- /dev/null
+++ b/arch/sparc/kernel/sun4m_smp.c
@@ -0,0 +1,451 @@
+/* sun4m_smp.c: Sparc SUN4M SMP support.
+ *
+ * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
+ */
+
+#include <asm/head.h>
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/threads.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/interrupt.h>
+#include <linux/kernel_stat.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/mm.h>
+#include <linux/swap.h>
+#include <linux/profile.h>
+#include <asm/cacheflush.h>
+#include <asm/tlbflush.h>
+
+#include <asm/ptrace.h>
+#include <asm/atomic.h>
+
+#include <asm/delay.h>
+#include <asm/irq.h>
+#include <asm/page.h>
+#include <asm/pgalloc.h>
+#include <asm/pgtable.h>
+#include <asm/oplib.h>
+#include <asm/cpudata.h>
+
+#define IRQ_RESCHEDULE		13
+#define IRQ_STOP_CPU		14
+#define IRQ_CROSS_CALL		15
+
+extern ctxd_t *srmmu_ctx_table_phys;
+
+extern void calibrate_delay(void);
+
+extern volatile int smp_processors_ready;
+extern int smp_num_cpus;
+extern volatile unsigned long cpu_callin_map[NR_CPUS];
+extern unsigned char boot_cpu_id;
+extern int smp_activated;
+extern volatile int __cpu_number_map[NR_CPUS];
+extern volatile int __cpu_logical_map[NR_CPUS];
+extern volatile unsigned long ipi_count;
+extern volatile int smp_process_available;
+extern volatile int smp_commenced;
+extern int __smp4m_processor_id(void);
+
+/*#define SMP_DEBUG*/
+
+#ifdef SMP_DEBUG
+#define SMP_PRINTK(x)	printk x
+#else
+#define SMP_PRINTK(x)
+#endif
+
+static inline unsigned long swap(volatile unsigned long *ptr, unsigned long val)
+{
+	__asm__ __volatile__("swap [%1], %0\n\t" :
+			     "=&r" (val), "=&r" (ptr) :
+			     "0" (val), "1" (ptr));
+	return val;
+}
+
+static void smp_setup_percpu_timer(void);
+extern void cpu_probe(void);
+
+void __init smp4m_callin(void)
+{
+	int cpuid = hard_smp_processor_id();
+
+	local_flush_cache_all();
+	local_flush_tlb_all();
+
+	set_irq_udt(boot_cpu_id);
+
+	/* Get our local ticker going. */
+	smp_setup_percpu_timer();
+
+	calibrate_delay();
+	smp_store_cpu_info(cpuid);
+
+	local_flush_cache_all();
+	local_flush_tlb_all();
+
+	/*
+	 * Unblock the master CPU _only_ when the scheduler state
+	 * of all secondary CPUs will be up-to-date, so after
+	 * the SMP initialization the master will be just allowed
+	 * to call the scheduler code.
+	 */
+	/* Allow master to continue. */
+	swap((unsigned long *)&cpu_callin_map[cpuid], 1);
+
+	local_flush_cache_all();
+	local_flush_tlb_all();
+	
+	cpu_probe();
+
+	/* Fix idle thread fields. */
+	__asm__ __volatile__("ld [%0], %%g6\n\t"
+			     : : "r" (&current_set[cpuid])
+			     : "memory" /* paranoid */);
+
+	/* Attach to the address space of init_task. */
+	atomic_inc(&init_mm.mm_count);
+	current->active_mm = &init_mm;
+
+	while(!smp_commenced)
+		barrier();
+
+	local_flush_cache_all();
+	local_flush_tlb_all();
+
+	local_irq_enable();
+}
+
+extern void init_IRQ(void);
+extern void cpu_panic(void);
+
+/*
+ *	Cycle through the processors asking the PROM to start each one.
+ */
+ 
+extern struct linux_prom_registers smp_penguin_ctable;
+extern unsigned long trapbase_cpu1[];
+extern unsigned long trapbase_cpu2[];
+extern unsigned long trapbase_cpu3[];
+
+void __init smp4m_boot_cpus(void)
+{
+	int cpucount = 0;
+	int i, mid;
+
+	printk("Entering SMP Mode...\n");
+
+	local_irq_enable();
+	cpus_clear(cpu_present_map);
+
+	for (i = 0; !cpu_find_by_instance(i, NULL, &mid); i++)
+		cpu_set(mid, cpu_present_map);
+
+	for(i=0; i < NR_CPUS; i++) {
+		__cpu_number_map[i] = -1;
+		__cpu_logical_map[i] = -1;
+	}
+
+	__cpu_number_map[boot_cpu_id] = 0;
+	__cpu_logical_map[0] = boot_cpu_id;
+	current_thread_info()->cpu = boot_cpu_id;
+
+	smp_store_cpu_info(boot_cpu_id);
+	set_irq_udt(boot_cpu_id);
+	smp_setup_percpu_timer();
+	local_flush_cache_all();
+	if(cpu_find_by_instance(1, NULL, NULL))
+		return;  /* Not an MP box. */
+	for(i = 0; i < NR_CPUS; i++) {
+		if(i == boot_cpu_id)
+			continue;
+
+		if (cpu_isset(i, cpu_present_map)) {
+			extern unsigned long sun4m_cpu_startup;
+			unsigned long *entry = &sun4m_cpu_startup;
+			struct task_struct *p;
+			int timeout;
+
+			/* Cook up an idler for this guy. */
+			p = fork_idle(i);
+			cpucount++;
+			current_set[i] = p->thread_info;
+			/* See trampoline.S for details... */
+			entry += ((i-1) * 3);
+
+			/*
+			 * Initialize the contexts table
+			 * Since the call to prom_startcpu() trashes the structure,
+			 * we need to re-initialize it for each cpu
+			 */
+			smp_penguin_ctable.which_io = 0;
+			smp_penguin_ctable.phys_addr = (unsigned int) srmmu_ctx_table_phys;
+			smp_penguin_ctable.reg_size = 0;
+
+			/* whirrr, whirrr, whirrrrrrrrr... */
+			printk("Starting CPU %d at %p\n", i, entry);
+			local_flush_cache_all();
+			prom_startcpu(cpu_data(i).prom_node,
+				      &smp_penguin_ctable, 0, (char *)entry);
+
+			/* wheee... it's going... */
+			for(timeout = 0; timeout < 10000; timeout++) {
+				if(cpu_callin_map[i])
+					break;
+				udelay(200);
+			}
+			if(cpu_callin_map[i]) {
+				/* Another "Red Snapper". */
+				__cpu_number_map[i] = i;
+				__cpu_logical_map[i] = i;
+			} else {
+				cpucount--;
+				printk("Processor %d is stuck.\n", i);
+			}
+		}
+		if(!(cpu_callin_map[i])) {
+			cpu_clear(i, cpu_present_map);
+			__cpu_number_map[i] = -1;
+		}
+	}
+	local_flush_cache_all();
+	if(cpucount == 0) {
+		printk("Error: only one Processor found.\n");
+		cpu_present_map = cpumask_of_cpu(smp_processor_id());
+	} else {
+		unsigned long bogosum = 0;
+		for(i = 0; i < NR_CPUS; i++) {
+			if (cpu_isset(i, cpu_present_map))
+				bogosum += cpu_data(i).udelay_val;
+		}
+		printk("Total of %d Processors activated (%lu.%02lu BogoMIPS).\n",
+		       cpucount + 1,
+		       bogosum/(500000/HZ),
+		       (bogosum/(5000/HZ))%100);
+		smp_activated = 1;
+		smp_num_cpus = cpucount + 1;
+	}
+
+	/* Free unneeded trap tables */
+	if (!cpu_isset(i, cpu_present_map)) {
+		ClearPageReserved(virt_to_page(trapbase_cpu1));
+		set_page_count(virt_to_page(trapbase_cpu1), 1);
+		free_page((unsigned long)trapbase_cpu1);
+		totalram_pages++;
+		num_physpages++;
+	}
+	if (!cpu_isset(2, cpu_present_map)) {
+		ClearPageReserved(virt_to_page(trapbase_cpu2));
+		set_page_count(virt_to_page(trapbase_cpu2), 1);
+		free_page((unsigned long)trapbase_cpu2);
+		totalram_pages++;
+		num_physpages++;
+	}
+	if (!cpu_isset(3, cpu_present_map)) {
+		ClearPageReserved(virt_to_page(trapbase_cpu3));
+		set_page_count(virt_to_page(trapbase_cpu3), 1);
+		free_page((unsigned long)trapbase_cpu3);
+		totalram_pages++;
+		num_physpages++;
+	}
+
+	/* Ok, they are spinning and ready to go. */
+	smp_processors_ready = 1;
+}
+
+/* At each hardware IRQ, we get this called to forward IRQ reception
+ * to the next processor.  The caller must disable the IRQ level being
+ * serviced globally so that there are no double interrupts received.
+ *
+ * XXX See sparc64 irq.c.
+ */
+void smp4m_irq_rotate(int cpu)
+{
+}
+
+/* Cross calls, in order to work efficiently and atomically do all
+ * the message passing work themselves, only stopcpu and reschedule
+ * messages come through here.
+ */
+void smp4m_message_pass(int target, int msg, unsigned long data, int wait)
+{
+	static unsigned long smp_cpu_in_msg[NR_CPUS];
+	cpumask_t mask;
+	int me = smp_processor_id();
+	int irq, i;
+
+	if(msg == MSG_RESCHEDULE) {
+		irq = IRQ_RESCHEDULE;
+
+		if(smp_cpu_in_msg[me])
+			return;
+	} else if(msg == MSG_STOP_CPU) {
+		irq = IRQ_STOP_CPU;
+	} else {
+		goto barf;
+	}
+
+	smp_cpu_in_msg[me]++;
+	if(target == MSG_ALL_BUT_SELF || target == MSG_ALL) {
+		mask = cpu_present_map;
+		if(target == MSG_ALL_BUT_SELF)
+			cpu_clear(me, mask);
+		for(i = 0; i < 4; i++) {
+			if (cpu_isset(i, mask))
+				set_cpu_int(i, irq);
+		}
+	} else {
+		set_cpu_int(target, irq);
+	}
+	smp_cpu_in_msg[me]--;
+
+	return;
+barf:
+	printk("Yeeee, trying to send SMP msg(%d) on cpu %d\n", msg, me);
+	panic("Bogon SMP message pass.");
+}
+
+static struct smp_funcall {
+	smpfunc_t func;
+	unsigned long arg1;
+	unsigned long arg2;
+	unsigned long arg3;
+	unsigned long arg4;
+	unsigned long arg5;
+	unsigned long processors_in[NR_CPUS];  /* Set when ipi entered. */
+	unsigned long processors_out[NR_CPUS]; /* Set when ipi exited. */
+} ccall_info;
+
+static DEFINE_SPINLOCK(cross_call_lock);
+
+/* Cross calls must be serialized, at least currently. */
+void smp4m_cross_call(smpfunc_t func, unsigned long arg1, unsigned long arg2,
+		    unsigned long arg3, unsigned long arg4, unsigned long arg5)
+{
+	if(smp_processors_ready) {
+		register int ncpus = smp_num_cpus;
+		unsigned long flags;
+
+		spin_lock_irqsave(&cross_call_lock, flags);
+
+		/* Init function glue. */
+		ccall_info.func = func;
+		ccall_info.arg1 = arg1;
+		ccall_info.arg2 = arg2;
+		ccall_info.arg3 = arg3;
+		ccall_info.arg4 = arg4;
+		ccall_info.arg5 = arg5;
+
+		/* Init receive/complete mapping, plus fire the IPI's off. */
+		{
+			cpumask_t mask = cpu_present_map;
+			register int i;
+
+			cpu_clear(smp_processor_id(), mask);
+			for(i = 0; i < ncpus; i++) {
+				if (cpu_isset(i, mask)) {
+					ccall_info.processors_in[i] = 0;
+					ccall_info.processors_out[i] = 0;
+					set_cpu_int(i, IRQ_CROSS_CALL);
+				} else {
+					ccall_info.processors_in[i] = 1;
+					ccall_info.processors_out[i] = 1;
+				}
+			}
+		}
+
+		{
+			register int i;
+
+			i = 0;
+			do {
+				while(!ccall_info.processors_in[i])
+					barrier();
+			} while(++i < ncpus);
+
+			i = 0;
+			do {
+				while(!ccall_info.processors_out[i])
+					barrier();
+			} while(++i < ncpus);
+		}
+
+		spin_unlock_irqrestore(&cross_call_lock, flags);
+	}
+}
+
+/* Running cross calls. */
+void smp4m_cross_call_irq(void)
+{
+	int i = smp_processor_id();
+
+	ccall_info.processors_in[i] = 1;
+	ccall_info.func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3,
+			ccall_info.arg4, ccall_info.arg5);
+	ccall_info.processors_out[i] = 1;
+}
+
+void smp4m_percpu_timer_interrupt(struct pt_regs *regs)
+{
+	int cpu = smp_processor_id();
+
+	clear_profile_irq(cpu);
+
+	profile_tick(CPU_PROFILING, regs);
+
+	if(!--prof_counter(cpu)) {
+		int user = user_mode(regs);
+
+		irq_enter();
+		update_process_times(user);
+		irq_exit();
+
+		prof_counter(cpu) = prof_multiplier(cpu);
+	}
+}
+
+extern unsigned int lvl14_resolution;
+
+static void __init smp_setup_percpu_timer(void)
+{
+	int cpu = smp_processor_id();
+
+	prof_counter(cpu) = prof_multiplier(cpu) = 1;
+	load_profile_irq(cpu, lvl14_resolution);
+
+	if(cpu == boot_cpu_id)
+		enable_pil_irq(14);
+}
+
+void __init smp4m_blackbox_id(unsigned *addr)
+{
+	int rd = *addr & 0x3e000000;
+	int rs1 = rd >> 11;
+	
+	addr[0] = 0x81580000 | rd;		/* rd %tbr, reg */
+	addr[1] = 0x8130200c | rd | rs1;    	/* srl reg, 0xc, reg */
+	addr[2] = 0x80082003 | rd | rs1;	/* and reg, 3, reg */
+}
+
+void __init smp4m_blackbox_current(unsigned *addr)
+{
+	int rd = *addr & 0x3e000000;
+	int rs1 = rd >> 11;
+	
+	addr[0] = 0x81580000 | rd;		/* rd %tbr, reg */
+	addr[2] = 0x8130200a | rd | rs1;    	/* srl reg, 0xa, reg */
+	addr[4] = 0x8008200c | rd | rs1;	/* and reg, 3, reg */
+}
+
+void __init sun4m_init_smp(void)
+{
+	BTFIXUPSET_BLACKBOX(hard_smp_processor_id, smp4m_blackbox_id);
+	BTFIXUPSET_BLACKBOX(load_current, smp4m_blackbox_current);
+	BTFIXUPSET_CALL(smp_cross_call, smp4m_cross_call, BTFIXUPCALL_NORM);
+	BTFIXUPSET_CALL(smp_message_pass, smp4m_message_pass, BTFIXUPCALL_NORM);
+	BTFIXUPSET_CALL(__hard_smp_processor_id, __smp4m_processor_id, BTFIXUPCALL_NORM);
+}