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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/sparc64/kernel/smp.c
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!
Diffstat (limited to 'arch/sparc64/kernel/smp.c')
-rw-r--r--arch/sparc64/kernel/smp.c1244
1 files changed, 1244 insertions, 0 deletions
diff --git a/arch/sparc64/kernel/smp.c b/arch/sparc64/kernel/smp.c
new file mode 100644
index 000000000000..6dff06a44e76
--- /dev/null
+++ b/arch/sparc64/kernel/smp.c
@@ -0,0 +1,1244 @@
+/* smp.c: Sparc64 SMP support.
+ *
+ * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/pagemap.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/delay.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/fs.h>
+#include <linux/seq_file.h>
+#include <linux/cache.h>
+#include <linux/jiffies.h>
+#include <linux/profile.h>
+#include <linux/bootmem.h>
+
+#include <asm/head.h>
+#include <asm/ptrace.h>
+#include <asm/atomic.h>
+#include <asm/tlbflush.h>
+#include <asm/mmu_context.h>
+#include <asm/cpudata.h>
+
+#include <asm/irq.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/oplib.h>
+#include <asm/uaccess.h>
+#include <asm/timer.h>
+#include <asm/starfire.h>
+#include <asm/tlb.h>
+
+extern int linux_num_cpus;
+extern void calibrate_delay(void);
+
+/* Please don't make this stuff initdata!!! --DaveM */
+static unsigned char boot_cpu_id;
+
+cpumask_t cpu_online_map = CPU_MASK_NONE;
+cpumask_t phys_cpu_present_map = CPU_MASK_NONE;
+static cpumask_t smp_commenced_mask;
+static cpumask_t cpu_callout_map;
+
+void smp_info(struct seq_file *m)
+{
+ int i;
+
+ seq_printf(m, "State:\n");
+ for (i = 0; i < NR_CPUS; i++) {
+ if (cpu_online(i))
+ seq_printf(m,
+ "CPU%d:\t\tonline\n", i);
+ }
+}
+
+void smp_bogo(struct seq_file *m)
+{
+ int i;
+
+ for (i = 0; i < NR_CPUS; i++)
+ if (cpu_online(i))
+ seq_printf(m,
+ "Cpu%dBogo\t: %lu.%02lu\n"
+ "Cpu%dClkTck\t: %016lx\n",
+ i, cpu_data(i).udelay_val / (500000/HZ),
+ (cpu_data(i).udelay_val / (5000/HZ)) % 100,
+ i, cpu_data(i).clock_tick);
+}
+
+void __init smp_store_cpu_info(int id)
+{
+ int cpu_node;
+
+ /* multiplier and counter set by
+ smp_setup_percpu_timer() */
+ cpu_data(id).udelay_val = loops_per_jiffy;
+
+ cpu_find_by_mid(id, &cpu_node);
+ cpu_data(id).clock_tick = prom_getintdefault(cpu_node,
+ "clock-frequency", 0);
+
+ cpu_data(id).pgcache_size = 0;
+ cpu_data(id).pte_cache[0] = NULL;
+ cpu_data(id).pte_cache[1] = NULL;
+ cpu_data(id).pgd_cache = NULL;
+ cpu_data(id).idle_volume = 1;
+}
+
+static void smp_setup_percpu_timer(void);
+
+static volatile unsigned long callin_flag = 0;
+
+extern void inherit_locked_prom_mappings(int save_p);
+
+static inline void cpu_setup_percpu_base(unsigned long cpu_id)
+{
+ __asm__ __volatile__("mov %0, %%g5\n\t"
+ "stxa %0, [%1] %2\n\t"
+ "membar #Sync"
+ : /* no outputs */
+ : "r" (__per_cpu_offset(cpu_id)),
+ "r" (TSB_REG), "i" (ASI_IMMU));
+}
+
+void __init smp_callin(void)
+{
+ int cpuid = hard_smp_processor_id();
+
+ inherit_locked_prom_mappings(0);
+
+ __flush_tlb_all();
+
+ cpu_setup_percpu_base(cpuid);
+
+ smp_setup_percpu_timer();
+
+ local_irq_enable();
+
+ calibrate_delay();
+ smp_store_cpu_info(cpuid);
+ callin_flag = 1;
+ __asm__ __volatile__("membar #Sync\n\t"
+ "flush %%g6" : : : "memory");
+
+ /* Clear this or we will die instantly when we
+ * schedule back to this idler...
+ */
+ clear_thread_flag(TIF_NEWCHILD);
+
+ /* Attach to the address space of init_task. */
+ atomic_inc(&init_mm.mm_count);
+ current->active_mm = &init_mm;
+
+ while (!cpu_isset(cpuid, smp_commenced_mask))
+ membar("#LoadLoad");
+
+ cpu_set(cpuid, cpu_online_map);
+}
+
+void cpu_panic(void)
+{
+ printk("CPU[%d]: Returns from cpu_idle!\n", smp_processor_id());
+ panic("SMP bolixed\n");
+}
+
+static unsigned long current_tick_offset;
+
+/* This tick register synchronization scheme is taken entirely from
+ * the ia64 port, see arch/ia64/kernel/smpboot.c for details and credit.
+ *
+ * The only change I've made is to rework it so that the master
+ * initiates the synchonization instead of the slave. -DaveM
+ */
+
+#define MASTER 0
+#define SLAVE (SMP_CACHE_BYTES/sizeof(unsigned long))
+
+#define NUM_ROUNDS 64 /* magic value */
+#define NUM_ITERS 5 /* likewise */
+
+static DEFINE_SPINLOCK(itc_sync_lock);
+static unsigned long go[SLAVE + 1];
+
+#define DEBUG_TICK_SYNC 0
+
+static inline long get_delta (long *rt, long *master)
+{
+ unsigned long best_t0 = 0, best_t1 = ~0UL, best_tm = 0;
+ unsigned long tcenter, t0, t1, tm;
+ unsigned long i;
+
+ for (i = 0; i < NUM_ITERS; i++) {
+ t0 = tick_ops->get_tick();
+ go[MASTER] = 1;
+ membar("#StoreLoad");
+ while (!(tm = go[SLAVE]))
+ membar("#LoadLoad");
+ go[SLAVE] = 0;
+ membar("#StoreStore");
+ t1 = tick_ops->get_tick();
+
+ if (t1 - t0 < best_t1 - best_t0)
+ best_t0 = t0, best_t1 = t1, best_tm = tm;
+ }
+
+ *rt = best_t1 - best_t0;
+ *master = best_tm - best_t0;
+
+ /* average best_t0 and best_t1 without overflow: */
+ tcenter = (best_t0/2 + best_t1/2);
+ if (best_t0 % 2 + best_t1 % 2 == 2)
+ tcenter++;
+ return tcenter - best_tm;
+}
+
+void smp_synchronize_tick_client(void)
+{
+ long i, delta, adj, adjust_latency = 0, done = 0;
+ unsigned long flags, rt, master_time_stamp, bound;
+#if DEBUG_TICK_SYNC
+ struct {
+ long rt; /* roundtrip time */
+ long master; /* master's timestamp */
+ long diff; /* difference between midpoint and master's timestamp */
+ long lat; /* estimate of itc adjustment latency */
+ } t[NUM_ROUNDS];
+#endif
+
+ go[MASTER] = 1;
+
+ while (go[MASTER])
+ membar("#LoadLoad");
+
+ local_irq_save(flags);
+ {
+ for (i = 0; i < NUM_ROUNDS; i++) {
+ delta = get_delta(&rt, &master_time_stamp);
+ if (delta == 0) {
+ done = 1; /* let's lock on to this... */
+ bound = rt;
+ }
+
+ if (!done) {
+ if (i > 0) {
+ adjust_latency += -delta;
+ adj = -delta + adjust_latency/4;
+ } else
+ adj = -delta;
+
+ tick_ops->add_tick(adj, current_tick_offset);
+ }
+#if DEBUG_TICK_SYNC
+ t[i].rt = rt;
+ t[i].master = master_time_stamp;
+ t[i].diff = delta;
+ t[i].lat = adjust_latency/4;
+#endif
+ }
+ }
+ local_irq_restore(flags);
+
+#if DEBUG_TICK_SYNC
+ for (i = 0; i < NUM_ROUNDS; i++)
+ printk("rt=%5ld master=%5ld diff=%5ld adjlat=%5ld\n",
+ t[i].rt, t[i].master, t[i].diff, t[i].lat);
+#endif
+
+ printk(KERN_INFO "CPU %d: synchronized TICK with master CPU (last diff %ld cycles,"
+ "maxerr %lu cycles)\n", smp_processor_id(), delta, rt);
+}
+
+static void smp_start_sync_tick_client(int cpu);
+
+static void smp_synchronize_one_tick(int cpu)
+{
+ unsigned long flags, i;
+
+ go[MASTER] = 0;
+
+ smp_start_sync_tick_client(cpu);
+
+ /* wait for client to be ready */
+ while (!go[MASTER])
+ membar("#LoadLoad");
+
+ /* now let the client proceed into his loop */
+ go[MASTER] = 0;
+ membar("#StoreLoad");
+
+ spin_lock_irqsave(&itc_sync_lock, flags);
+ {
+ for (i = 0; i < NUM_ROUNDS*NUM_ITERS; i++) {
+ while (!go[MASTER])
+ membar("#LoadLoad");
+ go[MASTER] = 0;
+ membar("#StoreStore");
+ go[SLAVE] = tick_ops->get_tick();
+ membar("#StoreLoad");
+ }
+ }
+ spin_unlock_irqrestore(&itc_sync_lock, flags);
+}
+
+extern unsigned long sparc64_cpu_startup;
+
+/* The OBP cpu startup callback truncates the 3rd arg cookie to
+ * 32-bits (I think) so to be safe we have it read the pointer
+ * contained here so we work on >4GB machines. -DaveM
+ */
+static struct thread_info *cpu_new_thread = NULL;
+
+static int __devinit smp_boot_one_cpu(unsigned int cpu)
+{
+ unsigned long entry =
+ (unsigned long)(&sparc64_cpu_startup);
+ unsigned long cookie =
+ (unsigned long)(&cpu_new_thread);
+ struct task_struct *p;
+ int timeout, ret, cpu_node;
+
+ p = fork_idle(cpu);
+ callin_flag = 0;
+ cpu_new_thread = p->thread_info;
+ cpu_set(cpu, cpu_callout_map);
+
+ cpu_find_by_mid(cpu, &cpu_node);
+ prom_startcpu(cpu_node, entry, cookie);
+
+ for (timeout = 0; timeout < 5000000; timeout++) {
+ if (callin_flag)
+ break;
+ udelay(100);
+ }
+ if (callin_flag) {
+ ret = 0;
+ } else {
+ printk("Processor %d is stuck.\n", cpu);
+ cpu_clear(cpu, cpu_callout_map);
+ ret = -ENODEV;
+ }
+ cpu_new_thread = NULL;
+
+ return ret;
+}
+
+static void spitfire_xcall_helper(u64 data0, u64 data1, u64 data2, u64 pstate, unsigned long cpu)
+{
+ u64 result, target;
+ int stuck, tmp;
+
+ if (this_is_starfire) {
+ /* map to real upaid */
+ cpu = (((cpu & 0x3c) << 1) |
+ ((cpu & 0x40) >> 4) |
+ (cpu & 0x3));
+ }
+
+ target = (cpu << 14) | 0x70;
+again:
+ /* Ok, this is the real Spitfire Errata #54.
+ * One must read back from a UDB internal register
+ * after writes to the UDB interrupt dispatch, but
+ * before the membar Sync for that write.
+ * So we use the high UDB control register (ASI 0x7f,
+ * ADDR 0x20) for the dummy read. -DaveM
+ */
+ tmp = 0x40;
+ __asm__ __volatile__(
+ "wrpr %1, %2, %%pstate\n\t"
+ "stxa %4, [%0] %3\n\t"
+ "stxa %5, [%0+%8] %3\n\t"
+ "add %0, %8, %0\n\t"
+ "stxa %6, [%0+%8] %3\n\t"
+ "membar #Sync\n\t"
+ "stxa %%g0, [%7] %3\n\t"
+ "membar #Sync\n\t"
+ "mov 0x20, %%g1\n\t"
+ "ldxa [%%g1] 0x7f, %%g0\n\t"
+ "membar #Sync"
+ : "=r" (tmp)
+ : "r" (pstate), "i" (PSTATE_IE), "i" (ASI_INTR_W),
+ "r" (data0), "r" (data1), "r" (data2), "r" (target),
+ "r" (0x10), "0" (tmp)
+ : "g1");
+
+ /* NOTE: PSTATE_IE is still clear. */
+ stuck = 100000;
+ do {
+ __asm__ __volatile__("ldxa [%%g0] %1, %0"
+ : "=r" (result)
+ : "i" (ASI_INTR_DISPATCH_STAT));
+ if (result == 0) {
+ __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
+ : : "r" (pstate));
+ return;
+ }
+ stuck -= 1;
+ if (stuck == 0)
+ break;
+ } while (result & 0x1);
+ __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
+ : : "r" (pstate));
+ if (stuck == 0) {
+ printk("CPU[%d]: mondo stuckage result[%016lx]\n",
+ smp_processor_id(), result);
+ } else {
+ udelay(2);
+ goto again;
+ }
+}
+
+static __inline__ void spitfire_xcall_deliver(u64 data0, u64 data1, u64 data2, cpumask_t mask)
+{
+ u64 pstate;
+ int i;
+
+ __asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
+ for_each_cpu_mask(i, mask)
+ spitfire_xcall_helper(data0, data1, data2, pstate, i);
+}
+
+/* Cheetah now allows to send the whole 64-bytes of data in the interrupt
+ * packet, but we have no use for that. However we do take advantage of
+ * the new pipelining feature (ie. dispatch to multiple cpus simultaneously).
+ */
+static void cheetah_xcall_deliver(u64 data0, u64 data1, u64 data2, cpumask_t mask)
+{
+ u64 pstate, ver;
+ int nack_busy_id, is_jalapeno;
+
+ if (cpus_empty(mask))
+ return;
+
+ /* Unfortunately, someone at Sun had the brilliant idea to make the
+ * busy/nack fields hard-coded by ITID number for this Ultra-III
+ * derivative processor.
+ */
+ __asm__ ("rdpr %%ver, %0" : "=r" (ver));
+ is_jalapeno = ((ver >> 32) == 0x003e0016);
+
+ __asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
+
+retry:
+ __asm__ __volatile__("wrpr %0, %1, %%pstate\n\t"
+ : : "r" (pstate), "i" (PSTATE_IE));
+
+ /* Setup the dispatch data registers. */
+ __asm__ __volatile__("stxa %0, [%3] %6\n\t"
+ "stxa %1, [%4] %6\n\t"
+ "stxa %2, [%5] %6\n\t"
+ "membar #Sync\n\t"
+ : /* no outputs */
+ : "r" (data0), "r" (data1), "r" (data2),
+ "r" (0x40), "r" (0x50), "r" (0x60),
+ "i" (ASI_INTR_W));
+
+ nack_busy_id = 0;
+ {
+ int i;
+
+ for_each_cpu_mask(i, mask) {
+ u64 target = (i << 14) | 0x70;
+
+ if (!is_jalapeno)
+ target |= (nack_busy_id << 24);
+ __asm__ __volatile__(
+ "stxa %%g0, [%0] %1\n\t"
+ "membar #Sync\n\t"
+ : /* no outputs */
+ : "r" (target), "i" (ASI_INTR_W));
+ nack_busy_id++;
+ }
+ }
+
+ /* Now, poll for completion. */
+ {
+ u64 dispatch_stat;
+ long stuck;
+
+ stuck = 100000 * nack_busy_id;
+ do {
+ __asm__ __volatile__("ldxa [%%g0] %1, %0"
+ : "=r" (dispatch_stat)
+ : "i" (ASI_INTR_DISPATCH_STAT));
+ if (dispatch_stat == 0UL) {
+ __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
+ : : "r" (pstate));
+ return;
+ }
+ if (!--stuck)
+ break;
+ } while (dispatch_stat & 0x5555555555555555UL);
+
+ __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
+ : : "r" (pstate));
+
+ if ((dispatch_stat & ~(0x5555555555555555UL)) == 0) {
+ /* Busy bits will not clear, continue instead
+ * of freezing up on this cpu.
+ */
+ printk("CPU[%d]: mondo stuckage result[%016lx]\n",
+ smp_processor_id(), dispatch_stat);
+ } else {
+ int i, this_busy_nack = 0;
+
+ /* Delay some random time with interrupts enabled
+ * to prevent deadlock.
+ */
+ udelay(2 * nack_busy_id);
+
+ /* Clear out the mask bits for cpus which did not
+ * NACK us.
+ */
+ for_each_cpu_mask(i, mask) {
+ u64 check_mask;
+
+ if (is_jalapeno)
+ check_mask = (0x2UL << (2*i));
+ else
+ check_mask = (0x2UL <<
+ this_busy_nack);
+ if ((dispatch_stat & check_mask) == 0)
+ cpu_clear(i, mask);
+ this_busy_nack += 2;
+ }
+
+ goto retry;
+ }
+ }
+}
+
+/* Send cross call to all processors mentioned in MASK
+ * except self.
+ */
+static void smp_cross_call_masked(unsigned long *func, u32 ctx, u64 data1, u64 data2, cpumask_t mask)
+{
+ u64 data0 = (((u64)ctx)<<32 | (((u64)func) & 0xffffffff));
+ int this_cpu = get_cpu();
+
+ cpus_and(mask, mask, cpu_online_map);
+ cpu_clear(this_cpu, mask);
+
+ if (tlb_type == spitfire)
+ spitfire_xcall_deliver(data0, data1, data2, mask);
+ else
+ cheetah_xcall_deliver(data0, data1, data2, mask);
+ /* NOTE: Caller runs local copy on master. */
+
+ put_cpu();
+}
+
+extern unsigned long xcall_sync_tick;
+
+static void smp_start_sync_tick_client(int cpu)
+{
+ cpumask_t mask = cpumask_of_cpu(cpu);
+
+ smp_cross_call_masked(&xcall_sync_tick,
+ 0, 0, 0, mask);
+}
+
+/* Send cross call to all processors except self. */
+#define smp_cross_call(func, ctx, data1, data2) \
+ smp_cross_call_masked(func, ctx, data1, data2, cpu_online_map)
+
+struct call_data_struct {
+ void (*func) (void *info);
+ void *info;
+ atomic_t finished;
+ int wait;
+};
+
+static DEFINE_SPINLOCK(call_lock);
+static struct call_data_struct *call_data;
+
+extern unsigned long xcall_call_function;
+
+/*
+ * You must not call this function with disabled interrupts or from a
+ * hardware interrupt handler or from a bottom half handler.
+ */
+int smp_call_function(void (*func)(void *info), void *info,
+ int nonatomic, int wait)
+{
+ struct call_data_struct data;
+ int cpus = num_online_cpus() - 1;
+ long timeout;
+
+ if (!cpus)
+ return 0;
+
+ /* Can deadlock when called with interrupts disabled */
+ WARN_ON(irqs_disabled());
+
+ data.func = func;
+ data.info = info;
+ atomic_set(&data.finished, 0);
+ data.wait = wait;
+
+ spin_lock(&call_lock);
+
+ call_data = &data;
+
+ smp_cross_call(&xcall_call_function, 0, 0, 0);
+
+ /*
+ * Wait for other cpus to complete function or at
+ * least snap the call data.
+ */
+ timeout = 1000000;
+ while (atomic_read(&data.finished) != cpus) {
+ if (--timeout <= 0)
+ goto out_timeout;
+ barrier();
+ udelay(1);
+ }
+
+ spin_unlock(&call_lock);
+
+ return 0;
+
+out_timeout:
+ spin_unlock(&call_lock);
+ printk("XCALL: Remote cpus not responding, ncpus=%ld finished=%ld\n",
+ (long) num_online_cpus() - 1L,
+ (long) atomic_read(&data.finished));
+ return 0;
+}
+
+void smp_call_function_client(int irq, struct pt_regs *regs)
+{
+ void (*func) (void *info) = call_data->func;
+ void *info = call_data->info;
+
+ clear_softint(1 << irq);
+ if (call_data->wait) {
+ /* let initiator proceed only after completion */
+ func(info);
+ atomic_inc(&call_data->finished);
+ } else {
+ /* let initiator proceed after getting data */
+ atomic_inc(&call_data->finished);
+ func(info);
+ }
+}
+
+extern unsigned long xcall_flush_tlb_mm;
+extern unsigned long xcall_flush_tlb_pending;
+extern unsigned long xcall_flush_tlb_kernel_range;
+extern unsigned long xcall_flush_tlb_all_spitfire;
+extern unsigned long xcall_flush_tlb_all_cheetah;
+extern unsigned long xcall_report_regs;
+extern unsigned long xcall_receive_signal;
+
+#ifdef DCACHE_ALIASING_POSSIBLE
+extern unsigned long xcall_flush_dcache_page_cheetah;
+#endif
+extern unsigned long xcall_flush_dcache_page_spitfire;
+
+#ifdef CONFIG_DEBUG_DCFLUSH
+extern atomic_t dcpage_flushes;
+extern atomic_t dcpage_flushes_xcall;
+#endif
+
+static __inline__ void __local_flush_dcache_page(struct page *page)
+{
+#ifdef DCACHE_ALIASING_POSSIBLE
+ __flush_dcache_page(page_address(page),
+ ((tlb_type == spitfire) &&
+ page_mapping(page) != NULL));
+#else
+ if (page_mapping(page) != NULL &&
+ tlb_type == spitfire)
+ __flush_icache_page(__pa(page_address(page)));
+#endif
+}
+
+void smp_flush_dcache_page_impl(struct page *page, int cpu)
+{
+ cpumask_t mask = cpumask_of_cpu(cpu);
+ int this_cpu = get_cpu();
+
+#ifdef CONFIG_DEBUG_DCFLUSH
+ atomic_inc(&dcpage_flushes);
+#endif
+ if (cpu == this_cpu) {
+ __local_flush_dcache_page(page);
+ } else if (cpu_online(cpu)) {
+ void *pg_addr = page_address(page);
+ u64 data0;
+
+ if (tlb_type == spitfire) {
+ data0 =
+ ((u64)&xcall_flush_dcache_page_spitfire);
+ if (page_mapping(page) != NULL)
+ data0 |= ((u64)1 << 32);
+ spitfire_xcall_deliver(data0,
+ __pa(pg_addr),
+ (u64) pg_addr,
+ mask);
+ } else {
+#ifdef DCACHE_ALIASING_POSSIBLE
+ data0 =
+ ((u64)&xcall_flush_dcache_page_cheetah);
+ cheetah_xcall_deliver(data0,
+ __pa(pg_addr),
+ 0, mask);
+#endif
+ }
+#ifdef CONFIG_DEBUG_DCFLUSH
+ atomic_inc(&dcpage_flushes_xcall);
+#endif
+ }
+
+ put_cpu();
+}
+
+void flush_dcache_page_all(struct mm_struct *mm, struct page *page)
+{
+ void *pg_addr = page_address(page);
+ cpumask_t mask = cpu_online_map;
+ u64 data0;
+ int this_cpu = get_cpu();
+
+ cpu_clear(this_cpu, mask);
+
+#ifdef CONFIG_DEBUG_DCFLUSH
+ atomic_inc(&dcpage_flushes);
+#endif
+ if (cpus_empty(mask))
+ goto flush_self;
+ if (tlb_type == spitfire) {
+ data0 = ((u64)&xcall_flush_dcache_page_spitfire);
+ if (page_mapping(page) != NULL)
+ data0 |= ((u64)1 << 32);
+ spitfire_xcall_deliver(data0,
+ __pa(pg_addr),
+ (u64) pg_addr,
+ mask);
+ } else {
+#ifdef DCACHE_ALIASING_POSSIBLE
+ data0 = ((u64)&xcall_flush_dcache_page_cheetah);
+ cheetah_xcall_deliver(data0,
+ __pa(pg_addr),
+ 0, mask);
+#endif
+ }
+#ifdef CONFIG_DEBUG_DCFLUSH
+ atomic_inc(&dcpage_flushes_xcall);
+#endif
+ flush_self:
+ __local_flush_dcache_page(page);
+
+ put_cpu();
+}
+
+void smp_receive_signal(int cpu)
+{
+ cpumask_t mask = cpumask_of_cpu(cpu);
+
+ if (cpu_online(cpu)) {
+ u64 data0 = (((u64)&xcall_receive_signal) & 0xffffffff);
+
+ if (tlb_type == spitfire)
+ spitfire_xcall_deliver(data0, 0, 0, mask);
+ else
+ cheetah_xcall_deliver(data0, 0, 0, mask);
+ }
+}
+
+void smp_receive_signal_client(int irq, struct pt_regs *regs)
+{
+ /* Just return, rtrap takes care of the rest. */
+ clear_softint(1 << irq);
+}
+
+void smp_report_regs(void)
+{
+ smp_cross_call(&xcall_report_regs, 0, 0, 0);
+}
+
+void smp_flush_tlb_all(void)
+{
+ if (tlb_type == spitfire)
+ smp_cross_call(&xcall_flush_tlb_all_spitfire, 0, 0, 0);
+ else
+ smp_cross_call(&xcall_flush_tlb_all_cheetah, 0, 0, 0);
+ __flush_tlb_all();
+}
+
+/* We know that the window frames of the user have been flushed
+ * to the stack before we get here because all callers of us
+ * are flush_tlb_*() routines, and these run after flush_cache_*()
+ * which performs the flushw.
+ *
+ * The SMP TLB coherency scheme we use works as follows:
+ *
+ * 1) mm->cpu_vm_mask is a bit mask of which cpus an address
+ * space has (potentially) executed on, this is the heuristic
+ * we use to avoid doing cross calls.
+ *
+ * Also, for flushing from kswapd and also for clones, we
+ * use cpu_vm_mask as the list of cpus to make run the TLB.
+ *
+ * 2) TLB context numbers are shared globally across all processors
+ * in the system, this allows us to play several games to avoid
+ * cross calls.
+ *
+ * One invariant is that when a cpu switches to a process, and
+ * that processes tsk->active_mm->cpu_vm_mask does not have the
+ * current cpu's bit set, that tlb context is flushed locally.
+ *
+ * If the address space is non-shared (ie. mm->count == 1) we avoid
+ * cross calls when we want to flush the currently running process's
+ * tlb state. This is done by clearing all cpu bits except the current
+ * processor's in current->active_mm->cpu_vm_mask and performing the
+ * flush locally only. This will force any subsequent cpus which run
+ * this task to flush the context from the local tlb if the process
+ * migrates to another cpu (again).
+ *
+ * 3) For shared address spaces (threads) and swapping we bite the
+ * bullet for most cases and perform the cross call (but only to
+ * the cpus listed in cpu_vm_mask).
+ *
+ * The performance gain from "optimizing" away the cross call for threads is
+ * questionable (in theory the big win for threads is the massive sharing of
+ * address space state across processors).
+ */
+void smp_flush_tlb_mm(struct mm_struct *mm)
+{
+ /*
+ * This code is called from two places, dup_mmap and exit_mmap. In the
+ * former case, we really need a flush. In the later case, the callers
+ * are single threaded exec_mmap (really need a flush), multithreaded
+ * exec_mmap case (do not need to flush, since the caller gets a new
+ * context via activate_mm), and all other callers of mmput() whence
+ * the flush can be optimized since the associated threads are dead and
+ * the mm is being torn down (__exit_mm and other mmput callers) or the
+ * owning thread is dissociating itself from the mm. The
+ * (atomic_read(&mm->mm_users) == 0) check ensures real work is done
+ * for single thread exec and dup_mmap cases. An alternate check might
+ * have been (current->mm != mm).
+ * Kanoj Sarcar
+ */
+ if (atomic_read(&mm->mm_users) == 0)
+ return;
+
+ {
+ u32 ctx = CTX_HWBITS(mm->context);
+ int cpu = get_cpu();
+
+ if (atomic_read(&mm->mm_users) == 1) {
+ mm->cpu_vm_mask = cpumask_of_cpu(cpu);
+ goto local_flush_and_out;
+ }
+
+ smp_cross_call_masked(&xcall_flush_tlb_mm,
+ ctx, 0, 0,
+ mm->cpu_vm_mask);
+
+ local_flush_and_out:
+ __flush_tlb_mm(ctx, SECONDARY_CONTEXT);
+
+ put_cpu();
+ }
+}
+
+void smp_flush_tlb_pending(struct mm_struct *mm, unsigned long nr, unsigned long *vaddrs)
+{
+ u32 ctx = CTX_HWBITS(mm->context);
+ int cpu = get_cpu();
+
+ if (mm == current->active_mm && atomic_read(&mm->mm_users) == 1) {
+ mm->cpu_vm_mask = cpumask_of_cpu(cpu);
+ goto local_flush_and_out;
+ } else {
+ /* This optimization is not valid. Normally
+ * we will be holding the page_table_lock, but
+ * there is an exception which is copy_page_range()
+ * when forking. The lock is held during the individual
+ * page table updates in the parent, but not at the
+ * top level, which is where we are invoked.
+ */
+ if (0) {
+ cpumask_t this_cpu_mask = cpumask_of_cpu(cpu);
+
+ /* By virtue of running under the mm->page_table_lock,
+ * and mmu_context.h:switch_mm doing the same, the
+ * following operation is safe.
+ */
+ if (cpus_equal(mm->cpu_vm_mask, this_cpu_mask))
+ goto local_flush_and_out;
+ }
+ }
+
+ smp_cross_call_masked(&xcall_flush_tlb_pending,
+ ctx, nr, (unsigned long) vaddrs,
+ mm->cpu_vm_mask);
+
+local_flush_and_out:
+ __flush_tlb_pending(ctx, nr, vaddrs);
+
+ put_cpu();
+}
+
+void smp_flush_tlb_kernel_range(unsigned long start, unsigned long end)
+{
+ start &= PAGE_MASK;
+ end = PAGE_ALIGN(end);
+ if (start != end) {
+ smp_cross_call(&xcall_flush_tlb_kernel_range,
+ 0, start, end);
+
+ __flush_tlb_kernel_range(start, end);
+ }
+}
+
+/* CPU capture. */
+/* #define CAPTURE_DEBUG */
+extern unsigned long xcall_capture;
+
+static atomic_t smp_capture_depth = ATOMIC_INIT(0);
+static atomic_t smp_capture_registry = ATOMIC_INIT(0);
+static unsigned long penguins_are_doing_time;
+
+void smp_capture(void)
+{
+ int result = atomic_add_ret(1, &smp_capture_depth);
+
+ if (result == 1) {
+ int ncpus = num_online_cpus();
+
+#ifdef CAPTURE_DEBUG
+ printk("CPU[%d]: Sending penguins to jail...",
+ smp_processor_id());
+#endif
+ penguins_are_doing_time = 1;
+ membar("#StoreStore | #LoadStore");
+ atomic_inc(&smp_capture_registry);
+ smp_cross_call(&xcall_capture, 0, 0, 0);
+ while (atomic_read(&smp_capture_registry) != ncpus)
+ membar("#LoadLoad");
+#ifdef CAPTURE_DEBUG
+ printk("done\n");
+#endif
+ }
+}
+
+void smp_release(void)
+{
+ if (atomic_dec_and_test(&smp_capture_depth)) {
+#ifdef CAPTURE_DEBUG
+ printk("CPU[%d]: Giving pardon to "
+ "imprisoned penguins\n",
+ smp_processor_id());
+#endif
+ penguins_are_doing_time = 0;
+ membar("#StoreStore | #StoreLoad");
+ atomic_dec(&smp_capture_registry);
+ }
+}
+
+/* Imprisoned penguins run with %pil == 15, but PSTATE_IE set, so they
+ * can service tlb flush xcalls...
+ */
+extern void prom_world(int);
+extern void save_alternate_globals(unsigned long *);
+extern void restore_alternate_globals(unsigned long *);
+void smp_penguin_jailcell(int irq, struct pt_regs *regs)
+{
+ unsigned long global_save[24];
+
+ clear_softint(1 << irq);
+
+ preempt_disable();
+
+ __asm__ __volatile__("flushw");
+ save_alternate_globals(global_save);
+ prom_world(1);
+ atomic_inc(&smp_capture_registry);
+ membar("#StoreLoad | #StoreStore");
+ while (penguins_are_doing_time)
+ membar("#LoadLoad");
+ restore_alternate_globals(global_save);
+ atomic_dec(&smp_capture_registry);
+ prom_world(0);
+
+ preempt_enable();
+}
+
+extern unsigned long xcall_promstop;
+
+void smp_promstop_others(void)
+{
+ smp_cross_call(&xcall_promstop, 0, 0, 0);
+}
+
+#define prof_multiplier(__cpu) cpu_data(__cpu).multiplier
+#define prof_counter(__cpu) cpu_data(__cpu).counter
+
+void smp_percpu_timer_interrupt(struct pt_regs *regs)
+{
+ unsigned long compare, tick, pstate;
+ int cpu = smp_processor_id();
+ int user = user_mode(regs);
+
+ /*
+ * Check for level 14 softint.
+ */
+ {
+ unsigned long tick_mask = tick_ops->softint_mask;
+
+ if (!(get_softint() & tick_mask)) {
+ extern void handler_irq(int, struct pt_regs *);
+
+ handler_irq(14, regs);
+ return;
+ }
+ clear_softint(tick_mask);
+ }
+
+ do {
+ profile_tick(CPU_PROFILING, regs);
+ if (!--prof_counter(cpu)) {
+ irq_enter();
+
+ if (cpu == boot_cpu_id) {
+ kstat_this_cpu.irqs[0]++;
+ timer_tick_interrupt(regs);
+ }
+
+ update_process_times(user);
+
+ irq_exit();
+
+ prof_counter(cpu) = prof_multiplier(cpu);
+ }
+
+ /* Guarantee that the following sequences execute
+ * uninterrupted.
+ */
+ __asm__ __volatile__("rdpr %%pstate, %0\n\t"
+ "wrpr %0, %1, %%pstate"
+ : "=r" (pstate)
+ : "i" (PSTATE_IE));
+
+ compare = tick_ops->add_compare(current_tick_offset);
+ tick = tick_ops->get_tick();
+
+ /* Restore PSTATE_IE. */
+ __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
+ : /* no outputs */
+ : "r" (pstate));
+ } while (time_after_eq(tick, compare));
+}
+
+static void __init smp_setup_percpu_timer(void)
+{
+ int cpu = smp_processor_id();
+ unsigned long pstate;
+
+ prof_counter(cpu) = prof_multiplier(cpu) = 1;
+
+ /* Guarantee that the following sequences execute
+ * uninterrupted.
+ */
+ __asm__ __volatile__("rdpr %%pstate, %0\n\t"
+ "wrpr %0, %1, %%pstate"
+ : "=r" (pstate)
+ : "i" (PSTATE_IE));
+
+ tick_ops->init_tick(current_tick_offset);
+
+ /* Restore PSTATE_IE. */
+ __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
+ : /* no outputs */
+ : "r" (pstate));
+}
+
+void __init smp_tick_init(void)
+{
+ boot_cpu_id = hard_smp_processor_id();
+ current_tick_offset = timer_tick_offset;
+
+ cpu_set(boot_cpu_id, cpu_online_map);
+ prof_counter(boot_cpu_id) = prof_multiplier(boot_cpu_id) = 1;
+}
+
+/* /proc/profile writes can call this, don't __init it please. */
+static DEFINE_SPINLOCK(prof_setup_lock);
+
+int setup_profiling_timer(unsigned int multiplier)
+{
+ unsigned long flags;
+ int i;
+
+ if ((!multiplier) || (timer_tick_offset / multiplier) < 1000)
+ return -EINVAL;
+
+ spin_lock_irqsave(&prof_setup_lock, flags);
+ for (i = 0; i < NR_CPUS; i++)
+ prof_multiplier(i) = multiplier;
+ current_tick_offset = (timer_tick_offset / multiplier);
+ spin_unlock_irqrestore(&prof_setup_lock, flags);
+
+ return 0;
+}
+
+void __init smp_prepare_cpus(unsigned int max_cpus)
+{
+ int instance, mid;
+
+ instance = 0;
+ while (!cpu_find_by_instance(instance, NULL, &mid)) {
+ if (mid < max_cpus)
+ cpu_set(mid, phys_cpu_present_map);
+ instance++;
+ }
+
+ if (num_possible_cpus() > max_cpus) {
+ instance = 0;
+ while (!cpu_find_by_instance(instance, NULL, &mid)) {
+ if (mid != boot_cpu_id) {
+ cpu_clear(mid, phys_cpu_present_map);
+ if (num_possible_cpus() <= max_cpus)
+ break;
+ }
+ instance++;
+ }
+ }
+
+ smp_store_cpu_info(boot_cpu_id);
+}
+
+void __devinit smp_prepare_boot_cpu(void)
+{
+ if (hard_smp_processor_id() >= NR_CPUS) {
+ prom_printf("Serious problem, boot cpu id >= NR_CPUS\n");
+ prom_halt();
+ }
+
+ current_thread_info()->cpu = hard_smp_processor_id();
+
+ cpu_set(smp_processor_id(), cpu_online_map);
+ cpu_set(smp_processor_id(), phys_cpu_present_map);
+}
+
+int __devinit __cpu_up(unsigned int cpu)
+{
+ int ret = smp_boot_one_cpu(cpu);
+
+ if (!ret) {
+ cpu_set(cpu, smp_commenced_mask);
+ while (!cpu_isset(cpu, cpu_online_map))
+ mb();
+ if (!cpu_isset(cpu, cpu_online_map)) {
+ ret = -ENODEV;
+ } else {
+ smp_synchronize_one_tick(cpu);
+ }
+ }
+ return ret;
+}
+
+void __init smp_cpus_done(unsigned int max_cpus)
+{
+ unsigned long bogosum = 0;
+ int i;
+
+ for (i = 0; i < NR_CPUS; i++) {
+ if (cpu_online(i))
+ bogosum += cpu_data(i).udelay_val;
+ }
+ printk("Total of %ld processors activated "
+ "(%lu.%02lu BogoMIPS).\n",
+ (long) num_online_cpus(),
+ bogosum/(500000/HZ),
+ (bogosum/(5000/HZ))%100);
+}
+
+/* This needn't do anything as we do not sleep the cpu
+ * inside of the idler task, so an interrupt is not needed
+ * to get a clean fast response.
+ *
+ * XXX Reverify this assumption... -DaveM
+ *
+ * Addendum: We do want it to do something for the signal
+ * delivery case, we detect that by just seeing
+ * if we are trying to send this to an idler or not.
+ */
+void smp_send_reschedule(int cpu)
+{
+ if (cpu_data(cpu).idle_volume == 0)
+ smp_receive_signal(cpu);
+}
+
+/* This is a nop because we capture all other cpus
+ * anyways when making the PROM active.
+ */
+void smp_send_stop(void)
+{
+}
+
+unsigned long __per_cpu_base;
+unsigned long __per_cpu_shift;
+
+EXPORT_SYMBOL(__per_cpu_base);
+EXPORT_SYMBOL(__per_cpu_shift);
+
+void __init setup_per_cpu_areas(void)
+{
+ unsigned long goal, size, i;
+ char *ptr;
+ /* Created by linker magic */
+ extern char __per_cpu_start[], __per_cpu_end[];
+
+ /* Copy section for each CPU (we discard the original) */
+ goal = ALIGN(__per_cpu_end - __per_cpu_start, PAGE_SIZE);
+
+#ifdef CONFIG_MODULES
+ if (goal < PERCPU_ENOUGH_ROOM)
+ goal = PERCPU_ENOUGH_ROOM;
+#endif
+ __per_cpu_shift = 0;
+ for (size = 1UL; size < goal; size <<= 1UL)
+ __per_cpu_shift++;
+
+ /* Make sure the resulting __per_cpu_base value
+ * will fit in the 43-bit sign extended IMMU
+ * TSB register.
+ */
+ ptr = __alloc_bootmem(size * NR_CPUS, PAGE_SIZE,
+ (unsigned long) __per_cpu_start);
+
+ __per_cpu_base = ptr - __per_cpu_start;
+
+ if ((__per_cpu_shift < PAGE_SHIFT) ||
+ (__per_cpu_base & ~PAGE_MASK) ||
+ (__per_cpu_base != (((long) __per_cpu_base << 20) >> 20))) {
+ prom_printf("PER_CPU: Invalid layout, "
+ "ptr[%p] shift[%lx] base[%lx]\n",
+ ptr, __per_cpu_shift, __per_cpu_base);
+ prom_halt();
+ }
+
+ for (i = 0; i < NR_CPUS; i++, ptr += size)
+ memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);
+
+ /* Finally, load in the boot cpu's base value.
+ * We abuse the IMMU TSB register for trap handler
+ * entry and exit loading of %g5. That is why it
+ * has to be page aligned.
+ */
+ cpu_setup_percpu_base(hard_smp_processor_id());
+}