/* keep track of when we need to update the rtc */
time_t last_rtc_update;
#ifdef CONFIG_PPC_ISERIES
-unsigned long iSeries_recal_titan = 0;
-unsigned long iSeries_recal_tb = 0;
-static unsigned long first_settimeofday = 1;
+static unsigned long __initdata iSeries_recal_titan;
+static signed long __initdata iSeries_recal_tb;
#endif
/* The decrementer counts down by 128 every 128ns on a 601. */
DEFINE_SPINLOCK(rtc_lock);
EXPORT_SYMBOL_GPL(rtc_lock);
-u64 tb_to_ns_scale;
-unsigned tb_to_ns_shift;
+static u64 tb_to_ns_scale __read_mostly;
+static unsigned tb_to_ns_shift __read_mostly;
+static unsigned long boot_tb __read_mostly;
struct gettimeofday_struct do_gtod;
static long timezone_offset;
unsigned long ppc_proc_freq;
+EXPORT_SYMBOL(ppc_proc_freq);
unsigned long ppc_tb_freq;
static u64 tb_last_jiffy __cacheline_aligned_in_smp;
run_posix_cpu_timers(current);
}
-#ifdef CONFIG_PPC_SPLPAR
/*
* Stuff for accounting stolen time.
*/
int initialized; /* thread is running */
u64 tb; /* last TB value read */
u64 purr; /* last PURR value read */
- spinlock_t lock;
};
+/*
+ * Each entry in the cpu_purr_data array is manipulated only by its
+ * "owner" cpu -- usually in the timer interrupt but also occasionally
+ * in process context for cpu online. As long as cpus do not touch
+ * each others' cpu_purr_data, disabling local interrupts is
+ * sufficient to serialize accesses.
+ */
static DEFINE_PER_CPU(struct cpu_purr_data, cpu_purr_data);
static void snapshot_tb_and_purr(void *data)
{
+ unsigned long flags;
struct cpu_purr_data *p = &__get_cpu_var(cpu_purr_data);
+ local_irq_save(flags);
p->tb = mftb();
p->purr = mfspr(SPRN_PURR);
wmb();
p->initialized = 1;
+ local_irq_restore(flags);
}
/*
*/
void snapshot_timebases(void)
{
- int cpu;
-
if (!cpu_has_feature(CPU_FTR_PURR))
return;
- for_each_possible_cpu(cpu)
- spin_lock_init(&per_cpu(cpu_purr_data, cpu).lock);
on_each_cpu(snapshot_tb_and_purr, NULL, 0, 1);
}
+/*
+ * Must be called with interrupts disabled.
+ */
void calculate_steal_time(void)
{
u64 tb, purr;
pme = &per_cpu(cpu_purr_data, smp_processor_id());
if (!pme->initialized)
return; /* this can happen in early boot */
- spin_lock(&pme->lock);
tb = mftb();
purr = mfspr(SPRN_PURR);
stolen = (tb - pme->tb) - (purr - pme->purr);
account_steal_time(current, stolen);
pme->tb = tb;
pme->purr = purr;
- spin_unlock(&pme->lock);
}
+#ifdef CONFIG_PPC_SPLPAR
/*
* Must be called before the cpu is added to the online map when
* a cpu is being brought up at runtime.
if (!cpu_has_feature(CPU_FTR_PURR))
return;
+ local_irq_save(flags);
pme = &per_cpu(cpu_purr_data, smp_processor_id());
- spin_lock_irqsave(&pme->lock, flags);
pme->tb = mftb();
pme->purr = mfspr(SPRN_PURR);
pme->initialized = 1;
- spin_unlock_irqrestore(&pme->lock, flags);
+ local_irq_restore(flags);
}
#endif /* CONFIG_PPC_SPLPAR */
* returned by the service processor for the timebase frequency.
*/
-static void iSeries_tb_recal(void)
+static int __init iSeries_tb_recal(void)
{
struct div_result divres;
unsigned long titan, tb;
+
+ /* Make sure we only run on iSeries */
+ if (!firmware_has_feature(FW_FEATURE_ISERIES))
+ return -ENODEV;
+
tb = get_tb();
titan = HvCallXm_loadTod();
if ( iSeries_recal_titan ) {
}
iSeries_recal_titan = titan;
iSeries_recal_tb = tb;
+
+ return 0;
}
-#endif
+late_initcall(iSeries_tb_recal);
+
+/* Called from platform early init */
+void __init iSeries_time_init_early(void)
+{
+ iSeries_recal_tb = get_tb();
+ iSeries_recal_titan = HvCallXm_loadTod();
+}
+#endif /* CONFIG_PPC_ISERIES */
/*
* For iSeries shared processors, we have to let the hypervisor
void __init smp_space_timers(unsigned int max_cpus)
{
int i;
- unsigned long half = tb_ticks_per_jiffy / 2;
- unsigned long offset = tb_ticks_per_jiffy / max_cpus;
u64 previous_tb = per_cpu(last_jiffy, boot_cpuid);
/* make sure tb > per_cpu(last_jiffy, cpu) for all cpus always */
previous_tb -= tb_ticks_per_jiffy;
- /*
- * The stolen time calculation for POWER5 shared-processor LPAR
- * systems works better if the two threads' timebase interrupts
- * are staggered by half a jiffy with respect to each other.
- */
+
for_each_possible_cpu(i) {
if (i == boot_cpuid)
continue;
- if (i == (boot_cpuid ^ 1))
- per_cpu(last_jiffy, i) =
- per_cpu(last_jiffy, boot_cpuid) - half;
- else if (i & 1)
- per_cpu(last_jiffy, i) =
- per_cpu(last_jiffy, i ^ 1) + half;
- else {
- previous_tb += offset;
- per_cpu(last_jiffy, i) = previous_tb;
- }
+ per_cpu(last_jiffy, i) = previous_tb;
}
}
#endif
{
if (__USE_RTC())
return get_rtc();
- return mulhdu(get_tb(), tb_to_ns_scale) << tb_to_ns_shift;
+ return mulhdu(get_tb() - boot_tb, tb_to_ns_scale) << tb_to_ns_shift;
}
int do_settimeofday(struct timespec *tv)
* to the RTC again, or write to the RTC but then they don't call
* settimeofday to perform this operation.
*/
-#ifdef CONFIG_PPC_ISERIES
- if (firmware_has_feature(FW_FEATURE_ISERIES) && first_settimeofday) {
- iSeries_tb_recal();
- first_settimeofday = 0;
- }
-#endif
/* Make userspace gettimeofday spin until we're done. */
++vdso_data->tb_update_count;
cpu = of_find_node_by_type(NULL, "cpu");
if (cpu) {
- fp = get_property(cpu, name, NULL);
+ fp = of_get_property(cpu, name, NULL);
if (fp) {
found = 1;
*val = of_read_ulong(fp, cells);
}
tb_to_ns_scale = scale;
tb_to_ns_shift = shift;
+ /* Save the current timebase to pretty up CONFIG_PRINTK_TIME */
+ boot_tb = get_tb();
tm = get_boot_time();
projects / mirror_ubuntu-zesty-kernel.git / blobdiff