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Diffstat (limited to 'arch/mips/kernel/time.c')
-rw-r--r--arch/mips/kernel/time.c28
1 files changed, 18 insertions, 10 deletions
diff --git a/arch/mips/kernel/time.c b/arch/mips/kernel/time.c
index fb749740551..8d0170969e2 100644
--- a/arch/mips/kernel/time.c
+++ b/arch/mips/kernel/time.c
@@ -5,8 +5,8 @@
*
* Common time service routines for MIPS machines.
*
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*/
@@ -21,11 +21,11 @@
#include <linux/timex.h>
#include <linux/smp.h>
#include <linux/spinlock.h>
-#include <linux/module.h>
+#include <linux/export.h>
#include <asm/cpu-features.h>
+#include <asm/cpu-type.h>
#include <asm/div64.h>
-#include <asm/smtc_ipi.h>
#include <asm/time.h>
/*
@@ -62,8 +62,8 @@ EXPORT_SYMBOL(perf_irq);
* time_init() - it does the following things.
*
* 1) plat_time_init() -
- * a) (optional) set up RTC routines,
- * b) (optional) calibrate and set the mips_hpt_frequency
+ * a) (optional) set up RTC routines,
+ * b) (optional) calibrate and set the mips_hpt_frequency
* (only needed if you intended to use cpu counter as timer interrupt
* source)
* 2) calculate a couple of cached variables for later usage
@@ -75,7 +75,7 @@ unsigned int mips_hpt_frequency;
* This function exists in order to cause an error due to a duplicate
* definition if platform code should have its own implementation. The hook
* to use instead is plat_time_init. plat_time_init does not receive the
- * irqaction pointer argument anymore. This is because any function which
+ * irqaction pointer argument anymore. This is because any function which
* initializes an interrupt timer now takes care of its own request_irq rsp.
* setup_irq calls and each clock_event_device should use its own
* struct irqrequest.
@@ -93,7 +93,7 @@ static __init int cpu_has_mfc0_count_bug(void)
case CPU_R4000MC:
/*
* V3.0 is documented as suffering from the mfc0 from count bug.
- * Afaik this is the last version of the R4000. Later versions
+ * Afaik this is the last version of the R4000. Later versions
* were marketed as R4400.
*/
return 1;
@@ -102,7 +102,7 @@ static __init int cpu_has_mfc0_count_bug(void)
case CPU_R4400SC:
case CPU_R4400MC:
/*
- * The published errata for the R4400 upto 3.0 say the CPU
+ * The published errata for the R4400 up to 3.0 say the CPU
* has the mfc0 from count bug.
*/
if ((current_cpu_data.processor_id & 0xff) <= 0x30)
@@ -121,6 +121,14 @@ void __init time_init(void)
{
plat_time_init();
- if (!mips_clockevent_init() || !cpu_has_mfc0_count_bug())
+ /*
+ * The use of the R4k timer as a clock event takes precedence;
+ * if reading the Count register might interfere with the timer
+ * interrupt, then we don't use the timer as a clock source.
+ * We may still use the timer as a clock source though if the
+ * timer interrupt isn't reliable; the interference doesn't
+ * matter then, because we don't use the interrupt.
+ */
+ if (mips_clockevent_init() != 0 || !cpu_has_mfc0_count_bug())
init_mips_clocksource();
}