[IA64] Convert to generic timekeeping/clocksource
This is a merge of Peter Keilty's initial patch (which was
revived by Bob Picco) for this with Hidetoshi Seto's fixes
and scaling improvements.
Acked-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
diff --git a/drivers/char/hpet.c b/drivers/char/hpet.c
index 0be700f..ba0e74a 100644
--- a/drivers/char/hpet.c
+++ b/drivers/char/hpet.c
@@ -29,6 +29,7 @@
#include <linux/bcd.h>
#include <linux/seq_file.h>
#include <linux/bitops.h>
+#include <linux/clocksource.h>
#include <asm/current.h>
#include <asm/uaccess.h>
@@ -51,8 +52,34 @@
#define HPET_RANGE_SIZE 1024 /* from HPET spec */
+#if BITS_PER_LONG == 64
+#define write_counter(V, MC) writeq(V, MC)
+#define read_counter(MC) readq(MC)
+#else
+#define write_counter(V, MC) writel(V, MC)
+#define read_counter(MC) readl(MC)
+#endif
+
static u32 hpet_nhpet, hpet_max_freq = HPET_USER_FREQ;
+static void __iomem *hpet_mctr;
+
+static cycle_t read_hpet(void)
+{
+ return (cycle_t)read_counter((void __iomem *)hpet_mctr);
+}
+
+static struct clocksource clocksource_hpet = {
+ .name = "hpet",
+ .rating = 250,
+ .read = read_hpet,
+ .mask = 0xffffffffffffffff,
+ .mult = 0, /*to be caluclated*/
+ .shift = 10,
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+static struct clocksource *hpet_clocksource;
+
/* A lock for concurrent access by app and isr hpet activity. */
static DEFINE_SPINLOCK(hpet_lock);
/* A lock for concurrent intermodule access to hpet and isr hpet activity. */
@@ -79,7 +106,7 @@
struct hpets *hp_next;
struct hpet __iomem *hp_hpet;
unsigned long hp_hpet_phys;
- struct time_interpolator *hp_interpolator;
+ struct clocksource *hp_clocksource;
unsigned long long hp_tick_freq;
unsigned long hp_delta;
unsigned int hp_ntimer;
@@ -94,13 +121,6 @@
#define HPET_PERIODIC 0x0004
#define HPET_SHARED_IRQ 0x0008
-#if BITS_PER_LONG == 64
-#define write_counter(V, MC) writeq(V, MC)
-#define read_counter(MC) readq(MC)
-#else
-#define write_counter(V, MC) writel(V, MC)
-#define read_counter(MC) readl(MC)
-#endif
#ifndef readq
static inline unsigned long long readq(void __iomem *addr)
@@ -737,27 +757,6 @@
static struct ctl_table_header *sysctl_header;
-static void hpet_register_interpolator(struct hpets *hpetp)
-{
-#ifdef CONFIG_TIME_INTERPOLATION
- struct time_interpolator *ti;
-
- ti = kzalloc(sizeof(*ti), GFP_KERNEL);
- if (!ti)
- return;
-
- ti->source = TIME_SOURCE_MMIO64;
- ti->shift = 10;
- ti->addr = &hpetp->hp_hpet->hpet_mc;
- ti->frequency = hpetp->hp_tick_freq;
- ti->drift = HPET_DRIFT;
- ti->mask = -1;
-
- hpetp->hp_interpolator = ti;
- register_time_interpolator(ti);
-#endif
-}
-
/*
* Adjustment for when arming the timer with
* initial conditions. That is, main counter
@@ -909,7 +908,16 @@
}
hpetp->hp_delta = hpet_calibrate(hpetp);
- hpet_register_interpolator(hpetp);
+
+ if (!hpet_clocksource) {
+ hpet_mctr = (void __iomem *)&hpetp->hp_hpet->hpet_mc;
+ CLKSRC_FSYS_MMIO_SET(clocksource_hpet.fsys_mmio, hpet_mctr);
+ clocksource_hpet.mult = clocksource_hz2mult(hpetp->hp_tick_freq,
+ clocksource_hpet.shift);
+ clocksource_register(&clocksource_hpet);
+ hpetp->hp_clocksource = &clocksource_hpet;
+ hpet_clocksource = &clocksource_hpet;
+ }
return 0;
}
@@ -995,7 +1003,7 @@
static int hpet_acpi_remove(struct acpi_device *device, int type)
{
- /* XXX need to unregister interpolator, dealloc mem, etc */
+ /* XXX need to unregister clocksource, dealloc mem, etc */
return -EINVAL;
}