summaryrefslogtreecommitdiffstats
path: root/drivers/sn/ioc4.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/sn/ioc4.c')
-rw-r--r--drivers/sn/ioc4.c36
1 files changed, 17 insertions, 19 deletions
diff --git a/drivers/sn/ioc4.c b/drivers/sn/ioc4.c
index 8562821e6498..83d2e90c581c 100644
--- a/drivers/sn/ioc4.c
+++ b/drivers/sn/ioc4.c
@@ -3,7 +3,7 @@
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
- * Copyright (C) 2005 Silicon Graphics, Inc. All Rights Reserved.
+ * Copyright (C) 2005-2006 Silicon Graphics, Inc. All Rights Reserved.
*/
/* This file contains the master driver module for use by SGI IOC4 subdrivers.
@@ -29,9 +29,9 @@
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/ioc4.h>
-#include <linux/mmtimer.h>
-#include <linux/rtc.h>
+#include <linux/ktime.h>
#include <linux/mutex.h>
+#include <linux/time.h>
#include <asm/sn/addrs.h>
#include <asm/sn/clksupport.h>
#include <asm/sn/shub_mmr.h>
@@ -43,7 +43,7 @@
/* Tweakable values */
/* PCI bus speed detection/calibration */
-#define IOC4_CALIBRATE_COUNT 63 /* Calibration cycle period */
+#define IOC4_CALIBRATE_COUNT 63 /* Calibration cycle period */
#define IOC4_CALIBRATE_CYCLES 256 /* Average over this many cycles */
#define IOC4_CALIBRATE_DISCARD 2 /* Discard first few cycles */
#define IOC4_CALIBRATE_LOW_MHZ 25 /* Lower bound on bus speed sanity */
@@ -143,11 +143,11 @@ ioc4_unregister_submodule(struct ioc4_submodule *is)
static void
ioc4_clock_calibrate(struct ioc4_driver_data *idd)
{
- extern unsigned long sn_rtc_cycles_per_second;
union ioc4_int_out int_out;
union ioc4_gpcr gpcr;
unsigned int state, last_state = 1;
- uint64_t start = 0, end, period;
+ struct timespec start_ts, end_ts;
+ uint64_t start, end, period;
unsigned int count = 0;
/* Enable output */
@@ -175,30 +175,28 @@ ioc4_clock_calibrate(struct ioc4_driver_data *idd)
if (!last_state && state) {
count++;
if (count == IOC4_CALIBRATE_END) {
- end = rtc_time();
+ ktime_get_ts(&end_ts);
break;
} else if (count == IOC4_CALIBRATE_DISCARD)
- start = rtc_time();
+ ktime_get_ts(&start_ts);
}
last_state = state;
} while (1);
/* Calculation rearranged to preserve intermediate precision.
* Logically:
- * 1. "end - start" gives us number of RTC cycles over all the
- * square wave cycles measured.
- * 2. Divide by number of square wave cycles to get number of
- * RTC cycles per square wave cycle.
+ * 1. "end - start" gives us the measurement period over all
+ * the square wave cycles.
+ * 2. Divide by number of square wave cycles to get the period
+ * of a square wave cycle.
* 3. Divide by 2*(int_out.fields.count+1), which is the formula
* by which the IOC4 generates the square wave, to get the
- * number of RTC cycles per IOC4 INT_OUT count.
- * 4. Divide by sn_rtc_cycles_per_second to get seconds per
- * count.
- * 5. Multiply by 1E9 to get nanoseconds per count.
+ * period of an IOC4 INT_OUT count.
*/
- period = ((end - start) * 1000000000) /
- (IOC4_CALIBRATE_CYCLES * 2 * (IOC4_CALIBRATE_COUNT + 1)
- * sn_rtc_cycles_per_second);
+ end = end_ts.tv_sec * NSEC_PER_SEC + end_ts.tv_nsec;
+ start = start_ts.tv_sec * NSEC_PER_SEC + start_ts.tv_nsec;
+ period = (end - start) /
+ (IOC4_CALIBRATE_CYCLES * 2 * (IOC4_CALIBRATE_COUNT + 1));
/* Bounds check the result. */
if (period > IOC4_CALIBRATE_LOW_LIMIT ||