Re: [PATCH 12/13] Time: i386/x86-64 Clocksource Drivers
From: Ingo Molnar
Date: Sat Nov 26 2005 - 09:57:19 EST
- clean up timeofday-arch-x86-64-part2.patch
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>
arch/i386/kernel/hpet.c | 35 ++++++++++---------
drivers/clocksource/acpi_pm.c | 50 ++++++++++++++-------------
drivers/clocksource/cyclone.c | 71 ++++++++++++++++++++-------------------
drivers/clocksource/tsc-interp.c | 55 ++++++++++++++----------------
4 files changed, 110 insertions(+), 101 deletions(-)
Index: linux/arch/i386/kernel/hpet.c
===================================================================
--- linux.orig/arch/i386/kernel/hpet.c
+++ linux/arch/i386/kernel/hpet.c
@@ -1,15 +1,16 @@
#include <linux/clocksource.h>
-#include <linux/hpet.h>
#include <linux/errno.h>
+#include <linux/hpet.h>
#include <linux/init.h>
-#include <asm/io.h>
+
#include <asm/hpet.h>
+#include <asm/io.h>
-#define HPET_MASK (0xFFFFFFFF)
-#define HPET_SHIFT 22
+#define HPET_MASK 0xFFFFFFFF
+#define HPET_SHIFT 22
/* FSEC = 10^-15 NSEC = 10^-9 */
-#define FSEC_PER_NSEC 1000000
+#define FSEC_PER_NSEC 1000000
static void *hpet_ptr;
@@ -19,13 +20,13 @@ static cycle_t read_hpet(void)
}
struct clocksource clocksource_hpet = {
- .name = "hpet",
- .rating = 250,
- .read = read_hpet,
- .mask = (cycle_t)HPET_MASK,
- .mult = 0, /* set below */
- .shift = HPET_SHIFT,
- .is_continuous = 1,
+ .name = "hpet",
+ .rating = 250,
+ .read = read_hpet,
+ .mask = (cycle_t)HPET_MASK,
+ .mult = 0, /* set below */
+ .shift = HPET_SHIFT,
+ .is_continuous = 1,
};
static int __init init_hpet_clocksource(void)
@@ -37,16 +38,16 @@ static int __init init_hpet_clocksource(
if (!hpet_address)
return -ENODEV;
- /* calculate the hpet address */
+ /* calculate the hpet address: */
hpet_base =
(void __iomem*)ioremap_nocache(hpet_address, HPET_MMAP_SIZE);
hpet_ptr = hpet_base + HPET_COUNTER;
- /* calculate the frequency */
+ /* calculate the frequency: */
hpet_period = readl(hpet_base + HPET_PERIOD);
-
- /* hpet period is in femto seconds per cycle
+ /*
+ * hpet period is in femto seconds per cycle
* so we need to convert this to ns/cyc units
* aproximated by mult/2^shift
*
@@ -61,6 +62,8 @@ static int __init init_hpet_clocksource(
clocksource_hpet.mult = (u32)tmp;
register_clocksource(&clocksource_hpet);
+
return 0;
}
+
module_init(init_hpet_clocksource);
Index: linux/drivers/clocksource/acpi_pm.c
===================================================================
--- linux.orig/drivers/clocksource/acpi_pm.c
+++ linux/drivers/clocksource/acpi_pm.c
@@ -16,7 +16,6 @@
* This file is licensed under the GPL v2.
*/
-
#include <linux/clocksource.h>
#include <linux/errno.h>
#include <linux/init.h>
@@ -26,19 +25,20 @@
#define PMTMR_TICKS_PER_SEC 3579545
#if (defined(CONFIG_X86) && (!defined(CONFIG_X86_64)))
-#include "mach_timer.h"
-#define PMTMR_EXPECTED_RATE ((PMTMR_TICKS_PER_SEC*CALIBRATE_TIME_MSEC)/1000)
+# include "mach_timer.h"
+# define PMTMR_EXPECTED_RATE ((PMTMR_TICKS_PER_SEC*CALIBRATE_TIME_MSEC)/1000)
#endif
-/* The I/O port the PMTMR resides at.
+/*
+ * The I/O port the PMTMR resides at.
* The location is detected during setup_arch(),
- * in arch/i386/acpi/boot.c */
+ * in arch/i386/acpi/boot.c
+ */
extern u32 acpi_pmtmr_ioport;
extern int acpi_pmtmr_buggy;
#define ACPI_PM_MASK 0xFFFFFF /* limit it to 24 bits */
-
static inline u32 read_pmtmr(void)
{
/* mask the output to 24 bits */
@@ -47,11 +47,13 @@ static inline u32 read_pmtmr(void)
static cycle_t acpi_pm_read_verified(void)
{
- u32 v1=0,v2=0,v3=0;
- /* It has been reported that because of various broken
+ u32 v1 = 0, v2 = 0, v3 = 0;
+
+ /*
+ * It has been reported that because of various broken
* chipsets (ICH4, PIIX4 and PIIX4E) where the ACPI PM clock
* source is not latched, so you must read it multiple
- * times to insure a safe value is read.
+ * times to ensure a safe value is read:
*/
do {
v1 = read_pmtmr();
@@ -63,31 +65,30 @@ static cycle_t acpi_pm_read_verified(voi
return (cycle_t)v2;
}
-
static cycle_t acpi_pm_read(void)
{
return (cycle_t)read_pmtmr();
}
struct clocksource clocksource_acpi_pm = {
- .name = "acpi_pm",
- .rating = 200,
- .read = acpi_pm_read,
- .mask = (cycle_t)ACPI_PM_MASK,
- .mult = 0, /*to be caluclated*/
- .shift = 22,
- .is_continuous = 1,
+ .name = "acpi_pm",
+ .rating = 200,
+ .read = acpi_pm_read,
+ .mask = (cycle_t)ACPI_PM_MASK,
+ .mult = 0, /*to be caluclated*/
+ .shift = 22,
+ .is_continuous = 1,
};
-#if (defined(CONFIG_X86) && (!defined(CONFIG_X86_64)))
+#if defined(CONFIG_X86) && !defined(CONFIG_X86_64)
/*
* Some boards have the PMTMR running way too fast. We check
* the PMTMR rate against PIT channel 2 to catch these cases.
*/
static int __init verify_pmtmr_rate(void)
{
- u32 value1, value2;
unsigned long count, delta;
+ u32 value1, value2;
mach_prepare_counter();
value1 = read_pmtmr();
@@ -95,7 +96,7 @@ static int __init verify_pmtmr_rate(void
value2 = read_pmtmr();
delta = (value2 - value1) & ACPI_PM_MASK;
- /* Check that the PMTMR delta is within 5% of what we expect */
+ /* check that the PMTMR delta is within 5% of what we expect: */
if (delta < (PMTMR_EXPECTED_RATE * 19) / 20 ||
delta > (PMTMR_EXPECTED_RATE * 21) / 20) {
printk(KERN_INFO "PM-Timer running at invalid rate: %lu%% of normal - aborting.\n", 100UL * delta / PMTMR_EXPECTED_RATE);
@@ -105,7 +106,7 @@ static int __init verify_pmtmr_rate(void
return 0;
}
#else
-#define verify_pmtmr_rate() (0)
+# define verify_pmtmr_rate() (0)
#endif
static int __init init_acpi_pm_clocksource(void)
@@ -117,9 +118,9 @@ static int __init init_acpi_pm_clocksour
return -ENODEV;
clocksource_acpi_pm.mult = clocksource_hz2mult(PMTMR_TICKS_PER_SEC,
- clocksource_acpi_pm.shift);
+ clocksource_acpi_pm.shift);
- /* "verify" this timing source */
+ /* "verify" this timing source: */
value1 = read_pmtmr();
for (i = 0; i < 10000; i++) {
value2 = read_pmtmr();
@@ -139,13 +140,14 @@ pm_good:
if (verify_pmtmr_rate() != 0)
return -ENODEV;
- /* check to see if pmtmr is known buggy */
+ /* check to see if pmtmr is known buggy: */
if (acpi_pmtmr_buggy) {
clocksource_acpi_pm.read = acpi_pm_read_verified;
clocksource_acpi_pm.rating = 110;
}
register_clocksource(&clocksource_acpi_pm);
+
return 0;
}
Index: linux/drivers/clocksource/cyclone.c
===================================================================
--- linux.orig/drivers/clocksource/cyclone.c
+++ linux/drivers/clocksource/cyclone.c
@@ -1,19 +1,20 @@
#include <linux/clocksource.h>
-#include <linux/errno.h>
#include <linux/string.h>
+#include <linux/errno.h>
#include <linux/timex.h>
#include <linux/init.h>
-#include <asm/io.h>
#include <asm/pgtable.h>
+#include <asm/io.h>
+
#include "mach_timer.h"
-#define CYCLONE_CBAR_ADDR 0xFEB00CD0 /* base address ptr*/
-#define CYCLONE_PMCC_OFFSET 0x51A0 /* offset to control register */
-#define CYCLONE_MPCS_OFFSET 0x51A8 /* offset to select register */
-#define CYCLONE_MPMC_OFFSET 0x51D0 /* offset to count register */
-#define CYCLONE_TIMER_FREQ 99780000 /* 100Mhz, but not really */
-#define CYCLONE_TIMER_MASK (0xFFFFFFFF) /* 32 bit mask */
+#define CYCLONE_CBAR_ADDR 0xFEB00CD0 /* base address ptr */
+#define CYCLONE_PMCC_OFFSET 0x51A0 /* offset to control register */
+#define CYCLONE_MPCS_OFFSET 0x51A8 /* offset to select register */
+#define CYCLONE_MPMC_OFFSET 0x51D0 /* offset to count register */
+#define CYCLONE_TIMER_FREQ 99780000 /* 100Mhz, but not really */
+#define CYCLONE_TIMER_MASK 0xFFFFFFFF /* 32 bit mask */
int use_cyclone = 0;
static void __iomem *cyclone_ptr;
@@ -24,77 +25,81 @@ static cycle_t read_cyclone(void)
}
struct clocksource clocksource_cyclone = {
- .name = "cyclone",
- .rating = 250,
- .read = read_cyclone,
- .mask = (cycle_t)CYCLONE_TIMER_MASK,
- .mult = 10,
- .shift = 0,
- .is_continuous = 1,
+ .name = "cyclone",
+ .rating = 250,
+ .read = read_cyclone,
+ .mask = (cycle_t)CYCLONE_TIMER_MASK,
+ .mult = 10,
+ .shift = 0,
+ .is_continuous = 1,
};
static int __init init_cyclone_clocksource(void)
{
unsigned long base; /* saved value from CBAR */
unsigned long offset;
- u32 __iomem* reg;
u32 __iomem* volatile cyclone_timer; /* Cyclone MPMC0 register */
+ u32 __iomem* reg;
int i;
- /*make sure we're on a summit box*/
- if (!use_cyclone) return -ENODEV;
+ /* make sure we're on a summit box: */
+ if (!use_cyclone)
+ return -ENODEV;
printk(KERN_INFO "Summit chipset: Starting Cyclone Counter.\n");
- /* find base address */
+ /* find base address: */
offset = CYCLONE_CBAR_ADDR;
reg = ioremap_nocache(offset, sizeof(reg));
- if(!reg){
+ if (!reg) {
printk(KERN_ERR "Summit chipset: Could not find valid CBAR register.\n");
return -ENODEV;
}
- /* even on 64bit systems, this is only 32bits */
+ /* even on 64bit systems, this is only 32bits: */
base = readl(reg);
- if(!base){
+ if (!base) {
printk(KERN_ERR "Summit chipset: Could not find valid CBAR value.\n");
return -ENODEV;
}
iounmap(reg);
- /* setup PMCC */
+ /* setup PMCC: */
offset = base + CYCLONE_PMCC_OFFSET;
reg = ioremap_nocache(offset, sizeof(reg));
- if(!reg){
+ if (!reg) {
printk(KERN_ERR "Summit chipset: Could not find valid PMCC register.\n");
return -ENODEV;
}
writel(0x00000001,reg);
iounmap(reg);
- /* setup MPCS */
+ /* setup MPCS: */
offset = base + CYCLONE_MPCS_OFFSET;
reg = ioremap_nocache(offset, sizeof(reg));
- if(!reg){
+ if (!reg) {
printk(KERN_ERR "Summit chipset: Could not find valid MPCS register.\n");
return -ENODEV;
}
writel(0x00000001,reg);
iounmap(reg);
- /* map in cyclone_timer */
+ /* map in cyclone_timer: */
offset = base + CYCLONE_MPMC_OFFSET;
cyclone_timer = ioremap_nocache(offset, sizeof(u64));
- if(!cyclone_timer){
+ if (!cyclone_timer) {
printk(KERN_ERR "Summit chipset: Could not find valid MPMC register.\n");
return -ENODEV;
}
- /*quick test to make sure its ticking*/
- for(i=0; i<3; i++){
+ /* quick test to make sure its ticking: */
+ for (i = 0; i < 3; i++){
u32 old = readl(cyclone_timer);
int stall = 100;
- while(stall--) barrier();
- if(readl(cyclone_timer) == old){
+
+ while (stall--)
+ barrier();
+
+ if (readl(cyclone_timer) == old) {
printk(KERN_ERR "Summit chipset: Counter not counting! DISABLED\n");
iounmap(cyclone_timer);
cyclone_timer = NULL;
@@ -103,7 +108,7 @@ static int __init init_cyclone_clocksour
}
cyclone_ptr = cyclone_timer;
- /* sort out mult/shift values */
+ /* sort out mult/shift values: */
clocksource_cyclone.shift = 22;
clocksource_cyclone.mult = clocksource_hz2mult(CYCLONE_TIMER_FREQ,
clocksource_cyclone.shift);
Index: linux/drivers/clocksource/tsc-interp.c
===================================================================
--- linux.orig/drivers/clocksource/tsc-interp.c
+++ linux/drivers/clocksource/tsc-interp.c
@@ -1,14 +1,15 @@
-/* TSC-Jiffies Interpolation clocksource
- Example interpolation clocksource.
-TODO:
- o per-cpu TSC offsets
-*/
+/*
+ * TSC-Jiffies Interpolation clocksource
+ * Example interpolation clocksource.
+ * TODO:
+ * o per-cpu TSC offsets
+ */
#include <linux/clocksource.h>
+#include <linux/jiffies.h>
+#include <linux/threads.h>
#include <linux/timer.h>
#include <linux/timex.h>
#include <linux/init.h>
-#include <linux/jiffies.h>
-#include <linux/threads.h>
#include <linux/smp.h>
static unsigned long current_tsc_khz = 0;
@@ -20,27 +21,27 @@ struct timer_list tsc_interp_timer;
static unsigned long mult, shift;
-#define NSEC_PER_JIFFY ((((unsigned long long)NSEC_PER_SEC)<<8)/ACTHZ)
-#define SHIFT_VAL 22
+#define NSEC_PER_JIFFY ((((unsigned long long)NSEC_PER_SEC)<<8)/ACTHZ)
+#define SHIFT_VAL 22
static cycle_t read_tsc_interp(void);
static void tsc_interp_update_callback(void);
static struct clocksource clocksource_tsc_interp = {
- .name = "tsc-interp",
- .rating = 150,
- .type = CLOCKSOURCE_FUNCTION,
- .read_fnct = read_tsc_interp,
- .mask = (cycle_t)((1ULL<<32)-1),
- .mult = 1<<SHIFT_VAL,
- .shift = SHIFT_VAL,
- .update_callback = tsc_interp_update_callback,
+ .name = "tsc-interp",
+ .rating = 150,
+ .type = CLOCKSOURCE_FUNCTION,
+ .read_fnct = read_tsc_interp,
+ .mask = (cycle_t)((1ULL<<32)-1),
+ .mult = 1<<SHIFT_VAL,
+ .shift = SHIFT_VAL,
+ .update_callback = tsc_interp_update_callback,
};
static void tsc_interp_sync(unsigned long unused)
{
- cycle_t tsc_now;
unsigned long jiffies_now;
+ cycle_t tsc_now;
do {
jiffies_now = jiffies;
@@ -55,13 +56,10 @@ static void tsc_interp_sync(unsigned lon
mod_timer(&tsc_interp_timer, jiffies+1);
}
-
static cycle_t read_tsc_interp(void)
{
- cycle_t ret;
- cycle_t now, then;
- unsigned long jiffs_now, jiffs_then;
- unsigned long seq;
+ unsigned long seq, jiffs_now, jiffs_then;
+ cycle_t ret, now, then;
do {
seq = read_seqbegin(&tsc_interp_lock);
@@ -75,7 +73,8 @@ static cycle_t read_tsc_interp(void)
rdtscll(now);
ret = (cycle_t)jiffs_then * NSEC_PER_JIFFY;
if (jiffs_then == jiffs_now)
- ret += min((cycle_t)NSEC_PER_JIFFY,(cycle_t)((now - then)*mult)>> shift);
+ ret += min((cycle_t)NSEC_PER_JIFFY,
+ (cycle_t)((now - then)*mult) >> shift);
else
ret += (cycle_t)(jiffs_now - jiffs_then)*NSEC_PER_JIFFY;
@@ -84,14 +83,13 @@ static cycle_t read_tsc_interp(void)
static void tsc_interp_update_callback(void)
{
- /* only update if tsc_khz has changed */
- if (current_tsc_khz != tsc_khz){
+ /* only update if tsc_khz has changed: */
+ if (current_tsc_khz != tsc_khz) {
current_tsc_khz = tsc_khz;
mult = clocksource_khz2mult(current_tsc_khz, shift);
}
}
-
static int __init init_tsc_interp_clocksource(void)
{
/* TSC initialization is done in arch/i386/kernel/tsc.c */
@@ -99,7 +97,7 @@ static int __init init_tsc_interp_clocks
current_tsc_khz = tsc_khz;
shift = SHIFT_VAL;
mult = clocksource_khz2mult(current_tsc_khz, shift);
- /* setup periodic soft-timer */
+ /* setup periodic soft-timer: */
init_timer(&tsc_interp_timer);
tsc_interp_timer.function = tsc_interp_sync;
tsc_interp_timer.expires = jiffies;
@@ -109,4 +107,5 @@ static int __init init_tsc_interp_clocks
}
return 0;
}
+
module_init(init_tsc_interp_clocksource);
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/