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-rw-r--r--arch/ppc64/kernel/time.c63
1 files changed, 63 insertions, 0 deletions
diff --git a/arch/ppc64/kernel/time.c b/arch/ppc64/kernel/time.c
index 33364a7d2cd..2348a75e050 100644
--- a/arch/ppc64/kernel/time.c
+++ b/arch/ppc64/kernel/time.c
@@ -107,6 +107,9 @@ void ppc_adjtimex(void);
static unsigned adjusting_time = 0;
+unsigned long ppc_proc_freq;
+unsigned long ppc_tb_freq;
+
static __inline__ void timer_check_rtc(void)
{
/*
@@ -472,6 +475,66 @@ int do_settimeofday(struct timespec *tv)
EXPORT_SYMBOL(do_settimeofday);
+#if defined(CONFIG_PPC_PSERIES) || defined(CONFIG_PPC_MAPLE) || defined(CONFIG_PPC_BPA)
+void __init generic_calibrate_decr(void)
+{
+ struct device_node *cpu;
+ struct div_result divres;
+ unsigned int *fp;
+ int node_found;
+
+ /*
+ * The cpu node should have a timebase-frequency property
+ * to tell us the rate at which the decrementer counts.
+ */
+ cpu = of_find_node_by_type(NULL, "cpu");
+
+ ppc_tb_freq = DEFAULT_TB_FREQ; /* hardcoded default */
+ node_found = 0;
+ if (cpu != 0) {
+ fp = (unsigned int *)get_property(cpu, "timebase-frequency",
+ NULL);
+ if (fp != 0) {
+ node_found = 1;
+ ppc_tb_freq = *fp;
+ }
+ }
+ if (!node_found)
+ printk(KERN_ERR "WARNING: Estimating decrementer frequency "
+ "(not found)\n");
+
+ ppc_proc_freq = DEFAULT_PROC_FREQ;
+ node_found = 0;
+ if (cpu != 0) {
+ fp = (unsigned int *)get_property(cpu, "clock-frequency",
+ NULL);
+ if (fp != 0) {
+ node_found = 1;
+ ppc_proc_freq = *fp;
+ }
+ }
+ if (!node_found)
+ printk(KERN_ERR "WARNING: Estimating processor frequency "
+ "(not found)\n");
+
+ of_node_put(cpu);
+
+ printk(KERN_INFO "time_init: decrementer frequency = %lu.%.6lu MHz\n",
+ ppc_tb_freq/1000000, ppc_tb_freq%1000000);
+ printk(KERN_INFO "time_init: processor frequency = %lu.%.6lu MHz\n",
+ ppc_proc_freq/1000000, ppc_proc_freq%1000000);
+
+ tb_ticks_per_jiffy = ppc_tb_freq / HZ;
+ tb_ticks_per_sec = tb_ticks_per_jiffy * HZ;
+ tb_ticks_per_usec = ppc_tb_freq / 1000000;
+ tb_to_us = mulhwu_scale_factor(ppc_tb_freq, 1000000);
+ div128_by_32(1024*1024, 0, tb_ticks_per_sec, &divres);
+ tb_to_xs = divres.result_low;
+
+ setup_default_decr();
+}
+#endif
+
void __init time_init(void)
{
/* This function is only called on the boot processor */