[PATCH] time: x86_64: split x86_64/kernel/time.c up
Changes
7 files changed · +687 −663
| File | Status | Add | Del | Content |
|---|---|---|---|---|
| arch/x86_64/kernel/Makefile | modified | +1 | −1 | View file |
| arch/x86_64/kernel/hpet.c | added | +453 | −0 | View file |
| arch/x86_64/kernel/time.c | modified | +4 | −660 | View file |
| arch/x86_64/kernel/tsc.c | added | +212 | −0 | View file |
| include/asm-x86_64/hpet.h | modified | +6 | −0 | View file |
| include/asm-x86_64/timex.h | modified | +11 | −0 | View file |
| kernel/tsacct.c | modified | +0 | −2 | View file |
Only the first 600 diff lines are shown. Download the complete patch.
arch/x86_64/kernel/Makefile
View filediff --git a/arch/x86_64/kernel/Makefile b/arch/x86_64/kernel/Makefile
index 6465eee..bb47e86 100644
--- a/arch/x86_64/kernel/Makefile
+++ b/arch/x86_64/kernel/Makefile
@@ -8,7 +8,7 @@ obj-y := process.o signal.o entry.o traps.o irq.o \
ptrace.o time.o ioport.o ldt.o setup.o i8259.o sys_x86_64.o \
x8664_ksyms.o i387.o syscall.o vsyscall.o \
setup64.o bootflag.o e820.o reboot.o quirks.o i8237.o \
- pci-dma.o pci-nommu.o alternative.o
+ pci-dma.o pci-nommu.o alternative.o hpet.o tsc.o
obj-$(CONFIG_STACKTRACE) += stacktrace.o
obj-$(CONFIG_X86_MCE) += mce.o therm_throt.o
arch/x86_64/kernel/hpet.c
View filediff --git a/arch/x86_64/kernel/hpet.c b/arch/x86_64/kernel/hpet.c
new file mode 100644
index 0000000..08ab37c
--- /dev/null
+++ b/arch/x86_64/kernel/hpet.c
@@ -0,0 +1,453 @@
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/init.h>
+#include <linux/mc146818rtc.h>
+#include <linux/time.h>
+#include <linux/clocksource.h>
+#include <linux/ioport.h>
+#include <linux/acpi.h>
+#include <linux/hpet.h>
+#include <asm/pgtable.h>
+#include <asm/vsyscall.h>
+#include <asm/timex.h>
+#include <asm/hpet.h>
+
+int nohpet __initdata;
+
+unsigned long hpet_address;
+unsigned long hpet_period; /* fsecs / HPET clock */
+unsigned long hpet_tick; /* HPET clocks / interrupt */
+
+int hpet_use_timer; /* Use counter of hpet for time keeping,
+ * otherwise PIT
+ */
+unsigned int do_gettimeoffset_hpet(void)
+{
+ /* cap counter read to one tick to avoid inconsistencies */
+ unsigned long counter = hpet_readl(HPET_COUNTER) - vxtime.last;
+ return (min(counter,hpet_tick) * vxtime.quot) >> US_SCALE;
+}
+
+#ifdef CONFIG_HPET
+static __init int late_hpet_init(void)
+{
+ struct hpet_data hd;
+ unsigned int ntimer;
+
+ if (!hpet_address)
+ return 0;
+
+ memset(&hd, 0, sizeof(hd));
+
+ ntimer = hpet_readl(HPET_ID);
+ ntimer = (ntimer & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT;
+ ntimer++;
+
+ /*
+ * Register with driver.
+ * Timer0 and Timer1 is used by platform.
+ */
+ hd.hd_phys_address = hpet_address;
+ hd.hd_address = (void __iomem *)fix_to_virt(FIX_HPET_BASE);
+ hd.hd_nirqs = ntimer;
+ hd.hd_flags = HPET_DATA_PLATFORM;
+ hpet_reserve_timer(&hd, 0);
+#ifdef CONFIG_HPET_EMULATE_RTC
+ hpet_reserve_timer(&hd, 1);
+#endif
+ hd.hd_irq[0] = HPET_LEGACY_8254;
+ hd.hd_irq[1] = HPET_LEGACY_RTC;
+ if (ntimer > 2) {
+ struct hpet *hpet;
+ struct hpet_timer *timer;
+ int i;
+
+ hpet = (struct hpet *) fix_to_virt(FIX_HPET_BASE);
+ timer = &hpet->hpet_timers[2];
+ for (i = 2; i < ntimer; timer++, i++)
+ hd.hd_irq[i] = (timer->hpet_config &
+ Tn_INT_ROUTE_CNF_MASK) >>
+ Tn_INT_ROUTE_CNF_SHIFT;
+
+ }
+
+ hpet_alloc(&hd);
+ return 0;
+}
+fs_initcall(late_hpet_init);
+#endif
+
+int hpet_timer_stop_set_go(unsigned long tick)
+{
+ unsigned int cfg;
+
+/*
+ * Stop the timers and reset the main counter.
+ */
+
+ cfg = hpet_readl(HPET_CFG);
+ cfg &= ~(HPET_CFG_ENABLE | HPET_CFG_LEGACY);
+ hpet_writel(cfg, HPET_CFG);
+ hpet_writel(0, HPET_COUNTER);
+ hpet_writel(0, HPET_COUNTER + 4);
+
+/*
+ * Set up timer 0, as periodic with first interrupt to happen at hpet_tick,
+ * and period also hpet_tick.
+ */
+ if (hpet_use_timer) {
+ hpet_writel(HPET_TN_ENABLE | HPET_TN_PERIODIC | HPET_TN_SETVAL |
+ HPET_TN_32BIT, HPET_T0_CFG);
+ hpet_writel(hpet_tick, HPET_T0_CMP); /* next interrupt */
+ hpet_writel(hpet_tick, HPET_T0_CMP); /* period */
+ cfg |= HPET_CFG_LEGACY;
+ }
+/*
+ * Go!
+ */
+
+ cfg |= HPET_CFG_ENABLE;
+ hpet_writel(cfg, HPET_CFG);
+
+ return 0;
+}
+
+int hpet_arch_init(void)
+{
+ unsigned int id;
+
+ if (!hpet_address)
+ return -1;
+ set_fixmap_nocache(FIX_HPET_BASE, hpet_address);
+ __set_fixmap(VSYSCALL_HPET, hpet_address, PAGE_KERNEL_VSYSCALL_NOCACHE);
+
+/*
+ * Read the period, compute tick and quotient.
+ */
+
+ id = hpet_readl(HPET_ID);
+
+ if (!(id & HPET_ID_VENDOR) || !(id & HPET_ID_NUMBER))
+ return -1;
+
+ hpet_period = hpet_readl(HPET_PERIOD);
+ if (hpet_period < 100000 || hpet_period > 100000000)
+ return -1;
+
+ hpet_tick = (FSEC_PER_TICK + hpet_period / 2) / hpet_period;
+
+ hpet_use_timer = (id & HPET_ID_LEGSUP);
+
+ return hpet_timer_stop_set_go(hpet_tick);
+}
+
+int hpet_reenable(void)
+{
+ return hpet_timer_stop_set_go(hpet_tick);
+}
+
+/*
+ * calibrate_tsc() calibrates the processor TSC in a very simple way, comparing
+ * it to the HPET timer of known frequency.
+ */
+
+#define TICK_COUNT 100000000
+#define TICK_MIN 5000
+
+/*
+ * Some platforms take periodic SMI interrupts with 5ms duration. Make sure none
+ * occurs between the reads of the hpet & TSC.
+ */
+static void __init read_hpet_tsc(int *hpet, int *tsc)
+{
+ int tsc1, tsc2, hpet1;
+
+ do {
+ tsc1 = get_cycles_sync();
+ hpet1 = hpet_readl(HPET_COUNTER);
+ tsc2 = get_cycles_sync();
+ } while (tsc2 - tsc1 > TICK_MIN);
+ *hpet = hpet1;
+ *tsc = tsc2;
+}
+
+unsigned int __init hpet_calibrate_tsc(void)
+{
+ int tsc_start, hpet_start;
+ int tsc_now, hpet_now;
+ unsigned long flags;
+
+ local_irq_save(flags);
+
+ read_hpet_tsc(&hpet_start, &tsc_start);
+
+ do {
+ local_irq_disable();
+ read_hpet_tsc(&hpet_now, &tsc_now);
+ local_irq_restore(flags);
+ } while ((tsc_now - tsc_start) < TICK_COUNT &&
+ (hpet_now - hpet_start) < TICK_COUNT);
+
+ return (tsc_now - tsc_start) * 1000000000L
+ / ((hpet_now - hpet_start) * hpet_period / 1000);
+}
+
+#ifdef CONFIG_HPET_EMULATE_RTC
+/* HPET in LegacyReplacement Mode eats up RTC interrupt line. When, HPET
+ * is enabled, we support RTC interrupt functionality in software.
+ * RTC has 3 kinds of interrupts:
+ * 1) Update Interrupt - generate an interrupt, every sec, when RTC clock
+ * is updated
+ * 2) Alarm Interrupt - generate an interrupt at a specific time of day
+ * 3) Periodic Interrupt - generate periodic interrupt, with frequencies
+ * 2Hz-8192Hz (2Hz-64Hz for non-root user) (all freqs in powers of 2)
+ * (1) and (2) above are implemented using polling at a frequency of
+ * 64 Hz. The exact frequency is a tradeoff between accuracy and interrupt
+ * overhead. (DEFAULT_RTC_INT_FREQ)
+ * For (3), we use interrupts at 64Hz or user specified periodic
+ * frequency, whichever is higher.
+ */
+#include <linux/rtc.h>
+
+#define DEFAULT_RTC_INT_FREQ 64
+#define RTC_NUM_INTS 1
+
+static unsigned long UIE_on;
+static unsigned long prev_update_sec;
+
+static unsigned long AIE_on;
+static struct rtc_time alarm_time;
+
+static unsigned long PIE_on;
+static unsigned long PIE_freq = DEFAULT_RTC_INT_FREQ;
+static unsigned long PIE_count;
+
+static unsigned long hpet_rtc_int_freq; /* RTC interrupt frequency */
+static unsigned int hpet_t1_cmp; /* cached comparator register */
+
+int is_hpet_enabled(void)
+{
+ return hpet_address != 0;
+}
+
+/*
+ * Timer 1 for RTC, we do not use periodic interrupt feature,
+ * even if HPET supports periodic interrupts on Timer 1.
+ * The reason being, to set up a periodic interrupt in HPET, we need to
+ * stop the main counter. And if we do that everytime someone diables/enables
+ * RTC, we will have adverse effect on main kernel timer running on Timer 0.
+ * So, for the time being, simulate the periodic interrupt in software.
+ *
+ * hpet_rtc_timer_init() is called for the first time and during subsequent
+ * interuppts reinit happens through hpet_rtc_timer_reinit().
+ */
+int hpet_rtc_timer_init(void)
+{
+ unsigned int cfg, cnt;
+ unsigned long flags;
+
+ if (!is_hpet_enabled())
+ return 0;
+ /*
+ * Set the counter 1 and enable the interrupts.
+ */
+ if (PIE_on && (PIE_freq > DEFAULT_RTC_INT_FREQ))
+ hpet_rtc_int_freq = PIE_freq;
+ else
+ hpet_rtc_int_freq = DEFAULT_RTC_INT_FREQ;
+
+ local_irq_save(flags);
+
+ cnt = hpet_readl(HPET_COUNTER);
+ cnt += ((hpet_tick*HZ)/hpet_rtc_int_freq);
+ hpet_writel(cnt, HPET_T1_CMP);
+ hpet_t1_cmp = cnt;
+
+ cfg = hpet_readl(HPET_T1_CFG);
+ cfg &= ~HPET_TN_PERIODIC;
+ cfg |= HPET_TN_ENABLE | HPET_TN_32BIT;
+ hpet_writel(cfg, HPET_T1_CFG);
+
+ local_irq_restore(flags);
+
+ return 1;
+}
+
+static void hpet_rtc_timer_reinit(void)
+{
+ unsigned int cfg, cnt, ticks_per_int, lost_ints;
+
+ if (unlikely(!(PIE_on | AIE_on | UIE_on))) {
+ cfg = hpet_readl(HPET_T1_CFG);
+ cfg &= ~HPET_TN_ENABLE;
+ hpet_writel(cfg, HPET_T1_CFG);
+ return;
+ }
+
+ if (PIE_on && (PIE_freq > DEFAULT_RTC_INT_FREQ))
+ hpet_rtc_int_freq = PIE_freq;
+ else
+ hpet_rtc_int_freq = DEFAULT_RTC_INT_FREQ;
+
+ /* It is more accurate to use the comparator value than current count.*/
+ ticks_per_int = hpet_tick * HZ / hpet_rtc_int_freq;
+ hpet_t1_cmp += ticks_per_int;
+ hpet_writel(hpet_t1_cmp, HPET_T1_CMP);
+
+ /*
+ * If the interrupt handler was delayed too long, the write above tries
+ * to schedule the next interrupt in the past and the hardware would
+ * not interrupt until the counter had wrapped around.
+ * So we have to check that the comparator wasn't set to a past time.
+ */
+ cnt = hpet_readl(HPET_COUNTER);
+ if (unlikely((int)(cnt - hpet_t1_cmp) > 0)) {
+ lost_ints = (cnt - hpet_t1_cmp) / ticks_per_int + 1;
+ /* Make sure that, even with the time needed to execute
+ * this code, the next scheduled interrupt has been moved
+ * back to the future: */
+ lost_ints++;
+
+ hpet_t1_cmp += lost_ints * ticks_per_int;
+ hpet_writel(hpet_t1_cmp, HPET_T1_CMP);
+
+ if (PIE_on)
+ PIE_count += lost_ints;
+
+ if (printk_ratelimit())
+ printk(KERN_WARNING "rtc: lost some interrupts at %ldHz.\n",
+ hpet_rtc_int_freq);
+ }
+}
+
+/*
+ * The functions below are called from rtc driver.
+ * Return 0 if HPET is not being used.
+ * Otherwise do the necessary changes and return 1.
+ */
+int hpet_mask_rtc_irq_bit(unsigned long bit_mask)
+{
+ if (!is_hpet_enabled())
+ return 0;
+
+ if (bit_mask & RTC_UIE)
+ UIE_on = 0;
+ if (bit_mask & RTC_PIE)
+ PIE_on = 0;
+ if (bit_mask & RTC_AIE)
+ AIE_on = 0;
+
+ return 1;
+}
+
+int hpet_set_rtc_irq_bit(unsigned long bit_mask)
+{
+ int timer_init_reqd = 0;
+
+ if (!is_hpet_enabled())
+ return 0;
+
+ if (!(PIE_on | AIE_on | UIE_on))
+ timer_init_reqd = 1;
+
+ if (bit_mask & RTC_UIE) {
+ UIE_on = 1;
+ }
+ if (bit_mask & RTC_PIE) {
+ PIE_on = 1;
+ PIE_count = 0;
+ }
+ if (bit_mask & RTC_AIE) {
+ AIE_on = 1;
+ }
+
+ if (timer_init_reqd)
+ hpet_rtc_timer_init();
+
+ return 1;
+}
+
+int hpet_set_alarm_time(unsigned char hrs, unsigned char min, unsigned char sec)
+{
+ if (!is_hpet_enabled())
+ return 0;
+
+ alarm_time.tm_hour = hrs;
+ alarm_time.tm_min = min;
+ alarm_time.tm_sec = sec;
+
+ return 1;
+}
+
+int hpet_set_periodic_freq(unsigned long freq)
+{
+ if (!is_hpet_enabled())
+ return 0;
+
+ PIE_freq = freq;
+ PIE_count = 0;
+
+ return 1;
+}
+
+int hpet_rtc_dropped_irq(void)
+{
+ if (!is_hpet_enabled())
+ return 0;
+
+ return 1;
+}
+
+irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+ struct rtc_time curr_time;
+ unsigned long rtc_int_flag = 0;
+ int call_rtc_interrupt = 0;
+
+ hpet_rtc_timer_reinit();
+
+ if (UIE_on | AIE_on) {
+ rtc_get_rtc_time(&curr_time);
+ }
+ if (UIE_on) {
+ if (curr_time.tm_sec != prev_update_sec) {
+ /* Set update int info, call real rtc int routine */
+ call_rtc_interrupt = 1;
+ rtc_int_flag = RTC_UF;
+ prev_update_sec = curr_time.tm_sec;
+ }
+ }
+ if (PIE_on) {
+ PIE_count++;
+ if (PIE_count >= hpet_rtc_int_freq/PIE_freq) {
+ /* Set periodic int info, call real rtc int routine */
+ call_rtc_interrupt = 1;
+ rtc_int_flag |= RTC_PF;
+ PIE_count = 0;
+ }
+ }
+ if (AIE_on) {
+ if ((curr_time.tm_sec == alarm_time.tm_sec) &&
+ (curr_time.tm_min == alarm_time.tm_min) &&
+ (curr_time.tm_hour == alarm_time.tm_hour)) {
+ /* Set alarm int info, call real rtc int routine */
+ call_rtc_interrupt = 1;
+ rtc_int_flag |= RTC_AF;
+ }
+ }
+ if (call_rtc_interrupt) {
+ rtc_int_flag |= (RTC_IRQF | (RTC_NUM_INTS << 8));
+ rtc_interrupt(rtc_int_flag, dev_id);
+ }
+ return IRQ_HANDLED;
+}
+#endif
+
+static int __init nohpet_setup(char *s)
+{
+ nohpet = 1;
+ return 1;
+}
+
+__setup("nohpet", nohpet_setup);
+
arch/x86_64/kernel/time.c
View filediff --git a/arch/x86_64/kernel/time.c b/arch/x86_64/kernel/time.c
index 76857ad..216fc9d 100644
--- a/arch/x86_64/kernel/time.c
+++ b/arch/x86_64/kernel/time.c
@@ -42,9 +42,10 @@
#include <linux/cpufreq.h>
#include <linux/hpet.h>
#include <asm/apic.h>
+#include <asm/hpet.h>
#ifdef CONFIG_CPU_FREQ
-static void cpufreq_delayed_get(void);
+extern void cpufreq_delayed_get(void);
#endif
extern void i8254_timer_resume(void);
extern int using_apic_timer;
@@ -55,22 +56,6 @@ DEFINE_SPINLOCK(rtc_lock);
EXPORT_SYMBOL(rtc_lock);
DEFINE_SPINLOCK(i8253_lock);
-int nohpet __initdata = 0;
-static int notsc __initdata = 0;
-
-#define USEC_PER_TICK (USEC_PER_SEC / HZ)
-#define NSEC_PER_TICK (NSEC_PER_SEC / HZ)
-#define FSEC_PER_TICK (FSEC_PER_SEC / HZ)
-
-#define NS_SCALE 10 /* 2^10, carefully chosen */
-#define US_SCALE 32 /* 2^32, arbitralrily chosen */
-
-unsigned int cpu_khz; /* TSC clocks / usec, not used here */
-EXPORT_SYMBOL(cpu_khz);
-unsigned long hpet_address;
-static unsigned long hpet_period; /* fsecs / HPET clock */
-unsigned long hpet_tick; /* HPET clocks / interrupt */
-int hpet_use_timer; /* Use counter of hpet for time keeping, otherwise PIT */
unsigned long vxtime_hz = PIT_TICK_RATE;
int report_lost_ticks; /* command line option */
unsigned long long monotonic_base;
@@ -81,34 +66,6 @@ volatile unsigned long __jiffies __section_jiffies = INITIAL_JIFFIES;
struct timespec __xtime __section_xtime;
struct timezone __sys_tz __section_sys_tz;
-/*
- * do_gettimeoffset() returns microseconds since last timer interrupt was
- * triggered by hardware. A memory read of HPET is slower than a register read
- * of TSC, but much more reliable. It's also synchronized to the timer
- * interrupt. Note that do_gettimeoffset() may return more than hpet_tick, if a
- * timer interrupt has happened already, but vxtime.trigger wasn't updated yet.
- * This is not a problem, because jiffies hasn't updated either. They are bound
- * together by xtime_lock.
- */
-
-static inline unsigned int do_gettimeoffset_tsc(void)
-{
- unsigned long t;
- unsigned long x;
- t = get_cycles_sync();
- if (t < vxtime.last_tsc)
- t = vxtime.last_tsc; /* hack */
- x = ((t - vxtime.last_tsc) * vxtime.tsc_quot) >> US_SCALE;
- return x;
-}
-
-static inline unsigned int do_gettimeoffset_hpet(void)
-{
- /* cap counter read to one tick to avoid inconsistencies */
- unsigned long counter = hpet_readl(HPET_COUNTER) - vxtime.last;
- return (min(counter,hpet_tick) * vxtime.quot) >> US_SCALE;
-}
-
unsigned int (*do_gettimeoffset)(void) = do_gettimeoffset_tsc;
/*
@@ -272,7 +229,7 @@ static void set_rtc_mmss(unsigned long nowtime)
* Note: This function is required to return accurate
* time even in the absence of multiple timer ticks.
*/
-static inline unsigned long long cycles_2_ns(unsigned long long cyc);
+extern unsigned long long cycles_2_ns(unsigned long long cyc);
unsigned long long monotonic_clock(void)
{
unsigned long seq;
@@ -462,40 +419,6 @@ static irqreturn_t timer_interrupt(int irq, void *dev_id)
return IRQ_HANDLED;
}
-static unsigned int cyc2ns_scale __read_mostly;
-
-static inline void set_cyc2ns_scale(unsigned long cpu_khz)
-{
- cyc2ns_scale = (NSEC_PER_MSEC << NS_SCALE) / cpu_khz;
-}
-
-static inline unsigned long long cycles_2_ns(unsigned long long cyc)
-{
- return (cyc * cyc2ns_scale) >> NS_SCALE;
-}
-
-unsigned long long sched_clock(void)
-{
- unsigned long a = 0;
-
-#if 0
- /* Don't do a HPET read here. Using TSC always is much faster
- and HPET may not be mapped yet when the scheduler first runs.
- Disadvantage is a small drift between CPUs in some configurations,
- but that should be tolerable. */
- if (__vxtime.mode == VXTIME_HPET)
- return (hpet_readl(HPET_COUNTER) * vxtime.quot) >> US_SCALE;
-#endif
-
- /* Could do CPU core sync here. Opteron can execute rdtsc speculatively,
- which means it is not completely exact and may not be monotonous between
- CPUs. But the errors should be too small to matter for scheduling
- purposes. */
-
- rdtscll(a);
- return cycles_2_ns(a);
-}
-
static unsigned long get_cmos_time(void)
{
unsigned int year, mon, day, hour, min, sec;
@@ -547,164 +470,6 @@ static unsigned long get_cmos_time(void)
return mktime(year, mon, day, hour, min, sec);
}
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arch/x86_64/kernel/tsc.c
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include/asm-x86_64/hpet.h
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include/asm-x86_64/timex.h
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kernel/tsacct.c
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