Skip to content
Projects
Groups
Snippets
Help
Loading...
Help
Support
Keyboard shortcuts
?
Submit feedback
Contribute to GitLab
Sign in / Register
Toggle navigation
L
linux
Project overview
Project overview
Details
Activity
Releases
Repository
Repository
Files
Commits
Branches
Tags
Contributors
Graph
Compare
Issues
0
Issues
0
List
Boards
Labels
Milestones
Merge Requests
0
Merge Requests
0
Analytics
Analytics
Repository
Value Stream
Wiki
Wiki
Snippets
Snippets
Members
Members
Collapse sidebar
Close sidebar
Activity
Graph
Create a new issue
Commits
Issue Boards
Open sidebar
nexedi
linux
Commits
abb2ed85
Commit
abb2ed85
authored
Apr 17, 2003
by
Alan Cox
Committed by
Linus Torvalds
Apr 17, 2003
Browse files
Options
Browse Files
Download
Email Patches
Plain Diff
[PATCH] generalise PIT usage in tsc code, plus tsc sync
parent
535f2150
Changes
1
Hide whitespace changes
Inline
Side-by-side
Showing
1 changed file
with
13 additions
and
24 deletions
+13
-24
arch/i386/kernel/timers/timer_tsc.c
arch/i386/kernel/timers/timer_tsc.c
+13
-24
No files found.
arch/i386/kernel/timers/timer_tsc.c
View file @
abb2ed85
...
@@ -15,6 +15,9 @@
...
@@ -15,6 +15,9 @@
/* processor.h for distable_tsc flag */
/* processor.h for distable_tsc flag */
#include <asm/processor.h>
#include <asm/processor.h>
#include "io_ports.h"
#include "mach_timer.h"
int
tsc_disable
__initdata
=
0
;
int
tsc_disable
__initdata
=
0
;
extern
spinlock_t
i8253_lock
;
extern
spinlock_t
i8253_lock
;
...
@@ -57,6 +60,8 @@ static inline unsigned long long cycles_2_ns(unsigned long long cyc)
...
@@ -57,6 +60,8 @@ static inline unsigned long long cycles_2_ns(unsigned long long cyc)
}
}
static
int
count2
;
/* counter for mark_offset_tsc() */
/* Cached *multiplier* to convert TSC counts to microseconds.
/* Cached *multiplier* to convert TSC counts to microseconds.
* (see the equation below).
* (see the equation below).
* Equal to 2^32 * (1 / (clocks per usec) ).
* Equal to 2^32 * (1 / (clocks per usec) ).
...
@@ -114,7 +119,7 @@ static void mark_offset_tsc(void)
...
@@ -114,7 +119,7 @@ static void mark_offset_tsc(void)
{
{
int
count
;
int
count
;
int
countmp
;
int
countmp
;
static
int
count1
=
0
,
count2
=
LATCH
;
static
int
count1
=
0
;
unsigned
long
long
this_offset
,
last_offset
;
unsigned
long
long
this_offset
,
last_offset
;
write_lock
(
&
monotonic_lock
);
write_lock
(
&
monotonic_lock
);
...
@@ -136,10 +141,10 @@ static void mark_offset_tsc(void)
...
@@ -136,10 +141,10 @@ static void mark_offset_tsc(void)
rdtsc
(
last_tsc_low
,
last_tsc_high
);
rdtsc
(
last_tsc_low
,
last_tsc_high
);
spin_lock
(
&
i8253_lock
);
spin_lock
(
&
i8253_lock
);
outb_p
(
0x00
,
0x43
);
/* latch the count ASAP */
outb_p
(
0x00
,
PIT_MODE
);
/* latch the count ASAP */
count
=
inb_p
(
0x4
0
);
/* read the latched count */
count
=
inb_p
(
PIT_CH
0
);
/* read the latched count */
count
|=
inb
(
0x4
0
)
<<
8
;
count
|=
inb
(
PIT_CH
0
)
<<
8
;
spin_unlock
(
&
i8253_lock
);
spin_unlock
(
&
i8253_lock
);
if
(
pit_latch_buggy
)
{
if
(
pit_latch_buggy
)
{
...
@@ -187,26 +192,11 @@ static void delay_tsc(unsigned long loops)
...
@@ -187,26 +192,11 @@ static void delay_tsc(unsigned long loops)
* device.
* device.
*/
*/
#define CALIBRATE_LATCH (5 * LATCH)
#define CALIBRATE_TIME (5 * 1000020/HZ)
#define CALIBRATE_TIME (5 * 1000020/HZ)
unsigned
long
__init
calibrate_tsc
(
void
)
unsigned
long
__init
calibrate_tsc
(
void
)
{
{
/* Set the Gate high, disable speaker */
mach_prepare_counter
();
outb
((
inb
(
0x61
)
&
~
0x02
)
|
0x01
,
0x61
);
/*
* Now let's take care of CTC channel 2
*
* Set the Gate high, program CTC channel 2 for mode 0,
* (interrupt on terminal count mode), binary count,
* load 5 * LATCH count, (LSB and MSB) to begin countdown.
*
* Some devices need a delay here.
*/
outb
(
0xb0
,
0x43
);
/* binary, mode 0, LSB/MSB, Ch 2 */
outb_p
(
CALIBRATE_LATCH
&
0xff
,
0x42
);
/* LSB of count */
outb_p
(
CALIBRATE_LATCH
>>
8
,
0x42
);
/* MSB of count */
{
{
unsigned
long
startlow
,
starthigh
;
unsigned
long
startlow
,
starthigh
;
...
@@ -214,10 +204,7 @@ unsigned long __init calibrate_tsc(void)
...
@@ -214,10 +204,7 @@ unsigned long __init calibrate_tsc(void)
unsigned
long
count
;
unsigned
long
count
;
rdtsc
(
startlow
,
starthigh
);
rdtsc
(
startlow
,
starthigh
);
count
=
0
;
mach_countup
(
&
count
);
do
{
count
++
;
}
while
((
inb
(
0x61
)
&
0x20
)
==
0
);
rdtsc
(
endlow
,
endhigh
);
rdtsc
(
endlow
,
endhigh
);
last_tsc_low
=
endlow
;
last_tsc_low
=
endlow
;
...
@@ -340,6 +327,8 @@ static int __init init_tsc(char* override)
...
@@ -340,6 +327,8 @@ static int __init init_tsc(char* override)
cpufreq_register_notifier
(
&
time_cpufreq_notifier_block
,
CPUFREQ_TRANSITION_NOTIFIER
);
cpufreq_register_notifier
(
&
time_cpufreq_notifier_block
,
CPUFREQ_TRANSITION_NOTIFIER
);
#endif
#endif
count2
=
LATCH
;
/* initialize counter for mark_offset_tsc() */
if
(
cpu_has_tsc
)
{
if
(
cpu_has_tsc
)
{
unsigned
long
tsc_quotient
=
calibrate_tsc
();
unsigned
long
tsc_quotient
=
calibrate_tsc
();
if
(
tsc_quotient
)
{
if
(
tsc_quotient
)
{
...
...
Write
Preview
Markdown
is supported
0%
Try again
or
attach a new file
Attach a file
Cancel
You are about to add
0
people
to the discussion. Proceed with caution.
Finish editing this message first!
Cancel
Please
register
or
sign in
to comment