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Diffstat (limited to 'arch/mips/kernel/sync-r4k.c')
-rw-r--r--arch/mips/kernel/sync-r4k.c62
1 files changed, 17 insertions, 45 deletions
diff --git a/arch/mips/kernel/sync-r4k.c b/arch/mips/kernel/sync-r4k.c
index 05dd170a83f..2242bdd4370 100644
--- a/arch/mips/kernel/sync-r4k.c
+++ b/arch/mips/kernel/sync-r4k.c
@@ -6,45 +6,32 @@
* not have done anything significant (but they may have had interrupts
* enabled briefly - prom_smp_finish() should not be responsible for enabling
* interrupts...)
- *
- * FIXME: broken for SMTC
*/
#include <linux/kernel.h>
-#include <linux/init.h>
#include <linux/irqflags.h>
#include <linux/cpumask.h>
#include <asm/r4k-timer.h>
-#include <asm/atomic.h>
+#include <linux/atomic.h>
#include <asm/barrier.h>
#include <asm/mipsregs.h>
-static atomic_t __cpuinitdata count_start_flag = ATOMIC_INIT(0);
-static atomic_t __cpuinitdata count_count_start = ATOMIC_INIT(0);
-static atomic_t __cpuinitdata count_count_stop = ATOMIC_INIT(0);
-static atomic_t __cpuinitdata count_reference = ATOMIC_INIT(0);
+static atomic_t count_start_flag = ATOMIC_INIT(0);
+static atomic_t count_count_start = ATOMIC_INIT(0);
+static atomic_t count_count_stop = ATOMIC_INIT(0);
+static atomic_t count_reference = ATOMIC_INIT(0);
-#define COUNTON 100
+#define COUNTON 100
#define NR_LOOPS 5
-void __cpuinit synchronise_count_master(void)
+void synchronise_count_master(int cpu)
{
int i;
unsigned long flags;
unsigned int initcount;
- int nslaves;
-
-#ifdef CONFIG_MIPS_MT_SMTC
- /*
- * SMTC needs to synchronise per VPE, not per CPU
- * ignore for now
- */
- return;
-#endif
- printk(KERN_INFO "Synchronize counters across %u CPUs: ",
- num_online_cpus());
+ printk(KERN_INFO "Synchronize counters for CPU %u: ", cpu);
local_irq_save(flags);
@@ -52,7 +39,7 @@ void __cpuinit synchronise_count_master(void)
* Notify the slaves that it's time to start
*/
atomic_set(&count_reference, read_c0_count());
- atomic_set(&count_start_flag, 1);
+ atomic_set(&count_start_flag, cpu);
smp_wmb();
/* Count will be initialised to current timer for all CPU's */
@@ -69,10 +56,9 @@ void __cpuinit synchronise_count_master(void)
* two CPUs.
*/
- nslaves = num_online_cpus()-1;
for (i = 0; i < NR_LOOPS; i++) {
- /* slaves loop on '!= ncpus' */
- while (atomic_read(&count_count_start) != nslaves)
+ /* slaves loop on '!= 2' */
+ while (atomic_read(&count_count_start) != 1)
mb();
atomic_set(&count_count_stop, 0);
smp_wmb();
@@ -89,7 +75,7 @@ void __cpuinit synchronise_count_master(void)
/*
* Wait for all slaves to leave the synchronization point:
*/
- while (atomic_read(&count_count_stop) != nslaves)
+ while (atomic_read(&count_count_stop) != 1)
mb();
atomic_set(&count_count_start, 0);
smp_wmb();
@@ -97,6 +83,7 @@ void __cpuinit synchronise_count_master(void)
}
/* Arrange for an interrupt in a short while */
write_c0_compare(read_c0_count() + COUNTON);
+ atomic_set(&count_start_flag, 0);
local_irq_restore(flags);
@@ -108,38 +95,25 @@ void __cpuinit synchronise_count_master(void)
printk("done.\n");
}
-void __cpuinit synchronise_count_slave(void)
+void synchronise_count_slave(int cpu)
{
int i;
- unsigned long flags;
unsigned int initcount;
- int ncpus;
-
-#ifdef CONFIG_MIPS_MT_SMTC
- /*
- * SMTC needs to synchronise per VPE, not per CPU
- * ignore for now
- */
- return;
-#endif
-
- local_irq_save(flags);
/*
* Not every cpu is online at the time this gets called,
* so we first wait for the master to say everyone is ready
*/
- while (!atomic_read(&count_start_flag))
+ while (atomic_read(&count_start_flag) != cpu)
mb();
/* Count will be initialised to next expire for all CPU's */
initcount = atomic_read(&count_reference);
- ncpus = num_online_cpus();
for (i = 0; i < NR_LOOPS; i++) {
atomic_inc(&count_count_start);
- while (atomic_read(&count_count_start) != ncpus)
+ while (atomic_read(&count_count_start) != 2)
mb();
/*
@@ -149,12 +123,10 @@ void __cpuinit synchronise_count_slave(void)
write_c0_count(initcount);
atomic_inc(&count_count_stop);
- while (atomic_read(&count_count_stop) != ncpus)
+ while (atomic_read(&count_count_stop) != 2)
mb();
}
/* Arrange for an interrupt in a short while */
write_c0_compare(read_c0_count() + COUNTON);
-
- local_irq_restore(flags);
}
#undef NR_LOOPS