#include <linux/device.h>
#include <linux/sysdev.h>
#include <linux/bcd.h>
+#include <linux/notifier.h>
+#include <linux/cpu.h>
#include <linux/kallsyms.h>
#include <linux/acpi.h>
#ifdef CONFIG_ACPI
#include <acpi/achware.h> /* for PM timer frequency */
+#include <acpi/acpi_bus.h>
#endif
#include <asm/8253pit.h>
#include <asm/pgtable.h>
#include <asm/sections.h>
#include <linux/cpufreq.h>
#include <linux/hpet.h>
-#ifdef CONFIG_X86_LOCAL_APIC
#include <asm/apic.h>
-#endif
#ifdef CONFIG_CPU_FREQ
static void cpufreq_delayed_get(void);
extern void i8254_timer_resume(void);
extern int using_apic_timer;
-static char *time_init_gtod(void);
+static char *timename = NULL;
DEFINE_SPINLOCK(rtc_lock);
EXPORT_SYMBOL(rtc_lock);
struct vxtime_data __vxtime __section_vxtime; /* for vsyscalls */
volatile unsigned long __jiffies __section_jiffies = INITIAL_JIFFIES;
-unsigned long __wall_jiffies __section_wall_jiffies = INITIAL_JIFFIES;
struct timespec __xtime __section_xtime;
struct timezone __sys_tz __section_sys_tz;
void do_gettimeofday(struct timeval *tv)
{
- unsigned long seq, t;
+ unsigned long seq;
unsigned int sec, usec;
do {
be found. Note when you fix it here you need to do the same
in arch/x86_64/kernel/vsyscall.c and export all needed
variables in vmlinux.lds. -AK */
-
- t = (jiffies - wall_jiffies) * USEC_PER_TICK +
- do_gettimeoffset();
- usec += t;
+ usec += do_gettimeoffset();
} while (read_seqretry(&xtime_lock, seq));
write_seqlock_irq(&xtime_lock);
- nsec -= do_gettimeoffset() * NSEC_PER_USEC +
- (jiffies - wall_jiffies) * NSEC_PER_TICK;
+ nsec -= do_gettimeoffset() * NSEC_PER_USEC;
wtm_sec = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec);
wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec);
{
unsigned long pc = instruction_pointer(regs);
- /* Assume the lock function has either no stack frame or only a single
- word. This checks if the address on the stack looks like a kernel
- text address.
- There is a small window for false hits, but in that case the tick
- is just accounted to the spinlock function.
- Better would be to write these functions in assembler again
- and check exactly. */
+ /* Assume the lock function has either no stack frame or a copy
+ of eflags from PUSHF
+ Eflags always has bits 22 and up cleared unlike kernel addresses. */
if (!user_mode(regs) && in_lock_functions(pc)) {
- char *v = *(char **)regs->rsp;
- if ((v >= _stext && v <= _etext) ||
- (v >= _sinittext && v <= _einittext) ||
- (v >= (char *)MODULES_VADDR && v <= (char *)MODULES_END))
- return (unsigned long)v;
- return ((unsigned long *)regs->rsp)[1];
+ unsigned long *sp = (unsigned long *)regs->rsp;
+ if (sp[0] >> 22)
+ return sp[0];
+ if (sp[1] >> 22)
+ return sp[1];
}
return pc;
}
* 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);
unsigned long long monotonic_clock(void)
{
unsigned long seq;
base = monotonic_base;
} while (read_seqretry(&xtime_lock, seq));
this_offset = get_cycles_sync();
- /* FIXME: 1000 or 1000000? */
- offset = (this_offset - last_offset)*1000 / cpu_khz;
+ offset = cycles_2_ns(this_offset - last_offset);
}
return base + offset;
}
EXPORT_SYMBOL(monotonic_clock);
-static noinline void handle_lost_ticks(int lost, struct pt_regs *regs)
+static noinline void handle_lost_ticks(int lost)
{
static long lost_count;
static int warned;
if (report_lost_ticks) {
printk(KERN_WARNING "time.c: Lost %d timer tick(s)! ", lost);
- print_symbol("rip %s)\n", regs->rip);
+ print_symbol("rip %s)\n", get_irq_regs()->rip);
}
if (lost_count == 1000 && !warned) {
printk(KERN_WARNING "warning: many lost ticks.\n"
KERN_WARNING "Your time source seems to be instable or "
"some driver is hogging interupts\n");
- print_symbol("rip %s\n", regs->rip);
+ print_symbol("rip %s\n", get_irq_regs()->rip);
if (vxtime.mode == VXTIME_TSC && vxtime.hpet_address) {
printk(KERN_WARNING "Falling back to HPET\n");
if (hpet_use_timer)
#endif
}
-void main_timer_handler(struct pt_regs *regs)
+void main_timer_handler(void)
{
static unsigned long rtc_update = 0;
unsigned long tsc;
offset %= USEC_PER_TICK;
}
- /* FIXME: 1000 or 1000000? */
- monotonic_base += (tsc - vxtime.last_tsc) * 1000000 / cpu_khz;
+ monotonic_base += cycles_2_ns(tsc - vxtime.last_tsc);
vxtime.last_tsc = tsc - vxtime.quot * delay / vxtime.tsc_quot;
(((long) offset << US_SCALE) / vxtime.tsc_quot) - 1;
}
- if (lost > 0) {
- handle_lost_ticks(lost, regs);
- jiffies += lost;
- }
+ if (lost > 0)
+ handle_lost_ticks(lost);
+ else
+ lost = 0;
/*
* Do the timer stuff.
*/
- do_timer(regs);
+ do_timer(lost + 1);
#ifndef CONFIG_SMP
- update_process_times(user_mode(regs));
+ update_process_times(user_mode(get_irq_regs()));
#endif
/*
* have to call the local interrupt handler.
*/
-#ifndef CONFIG_X86_LOCAL_APIC
- profile_tick(CPU_PROFILING, regs);
-#else
if (!using_apic_timer)
- smp_local_timer_interrupt(regs);
-#endif
+ smp_local_timer_interrupt();
/*
* If we have an externally synchronized Linux clock, then update CMOS clock
write_sequnlock(&xtime_lock);
}
-static irqreturn_t timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+static irqreturn_t timer_interrupt(int irq, void *dev_id)
{
if (apic_runs_main_timer > 1)
return IRQ_HANDLED;
- main_timer_handler(regs);
-#ifdef CONFIG_X86_LOCAL_APIC
+ main_timer_handler();
if (using_apic_timer)
smp_send_timer_broadcast_ipi();
-#endif
return IRQ_HANDLED;
}
void __init time_init(void)
{
- char *timename;
- char *gtod;
-
if (nohpet)
vxtime.hpet_address = 0;
}
vxtime.mode = VXTIME_TSC;
- gtod = time_init_gtod();
-
- printk(KERN_INFO "time.c: Using %ld.%06ld MHz WALL %s GTOD %s timer.\n",
- vxtime_hz / 1000000, vxtime_hz % 1000000, timename, gtod);
- printk(KERN_INFO "time.c: Detected %d.%03d MHz processor.\n",
- cpu_khz / 1000, cpu_khz % 1000);
vxtime.quot = (USEC_PER_SEC << US_SCALE) / vxtime_hz;
vxtime.tsc_quot = (USEC_PER_MSEC << US_SCALE) / cpu_khz;
vxtime.last_tsc = get_cycles_sync();
+ set_cyc2ns_scale(cpu_khz);
setup_irq(0, &irq0);
- set_cyc2ns_scale(cpu_khz);
+#ifndef CONFIG_SMP
+ time_init_gtod();
+#endif
}
/*
#ifdef CONFIG_SMP
if (apic_is_clustered_box())
return 1;
- /* Intel systems are normally all synchronized. Exceptions
- are handled in the check above. */
- if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
- return 0;
#endif
+ /* Most intel systems have synchronized TSCs except for
+ multi node systems */
+ if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) {
+#ifdef CONFIG_ACPI
+ /* But TSC doesn't tick in C3 so don't use it there */
+ if (acpi_fadt.length > 0 && acpi_fadt.plvl3_lat < 1000)
+ return 1;
+#endif
+ return 0;
+ }
+
/* Assume multi socket systems are not synchronized */
return num_present_cpus() > 1;
}
/*
* Decide what mode gettimeofday should use.
*/
-__init static char *time_init_gtod(void)
+void time_init_gtod(void)
{
char *timetype;
if (unsynchronized_tsc())
notsc = 1;
+
+ if (cpu_has(&boot_cpu_data, X86_FEATURE_RDTSCP))
+ vgetcpu_mode = VGETCPU_RDTSCP;
+ else
+ vgetcpu_mode = VGETCPU_LSL;
+
if (vxtime.hpet_address && notsc) {
timetype = hpet_use_timer ? "HPET" : "PIT/HPET";
if (hpet_use_timer)
timetype = hpet_use_timer ? "HPET/TSC" : "PIT/TSC";
vxtime.mode = VXTIME_TSC;
}
- return timetype;
+
+ printk(KERN_INFO "time.c: Using %ld.%06ld MHz WALL %s GTOD %s timer.\n",
+ vxtime_hz / 1000000, vxtime_hz % 1000000, timename, timetype);
+ printk(KERN_INFO "time.c: Detected %d.%03d MHz processor.\n",
+ cpu_khz / 1000, cpu_khz % 1000);
+ vxtime.quot = (USEC_PER_SEC << US_SCALE) / vxtime_hz;
+ vxtime.tsc_quot = (USEC_PER_MSEC << US_SCALE) / cpu_khz;
+ vxtime.last_tsc = get_cycles_sync();
+
+ set_cyc2ns_scale(cpu_khz);
}
__setup("report_lost_ticks", time_setup);
unsigned long flags;
unsigned long sec;
unsigned long ctime = get_cmos_time();
- unsigned long sleep_length = (ctime - sleep_start) * HZ;
+ long sleep_length = (ctime - sleep_start) * HZ;
+ if (sleep_length < 0) {
+ printk(KERN_WARNING "Time skew detected in timer resume!\n");
+ /* The time after the resume must not be earlier than the time
+ * before the suspend or some nasty things will happen
+ */
+ sleep_length = 0;
+ ctime = sleep_start;
+ }
if (vxtime.hpet_address)
hpet_reenable();
else
vxtime.last_tsc = get_cycles_sync();
write_sequnlock_irqrestore(&xtime_lock,flags);
jiffies += sleep_length;
- wall_jiffies += sleep_length;
monotonic_base += sleep_length * (NSEC_PER_SEC/HZ);
touch_softlockup_watchdog();
return 0;
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;
- local_irq_restore(flags);
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;
+ unsigned int cfg, cnt, ticks_per_int, lost_ints;
if (unlikely(!(PIE_on | AIE_on | UIE_on))) {
cfg = hpet_readl(HPET_T1_CFG);
hpet_rtc_int_freq = DEFAULT_RTC_INT_FREQ;
/* It is more accurate to use the comparator value than current count.*/
- cnt = hpet_t1_cmp;
- cnt += hpet_tick*HZ/hpet_rtc_int_freq;
- hpet_writel(cnt, HPET_T1_CMP);
- hpet_t1_cmp = cnt;
+ 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;
+
+ printk(KERN_WARNING "rtc: lost some interrupts at %ldHz.\n",
+ hpet_rtc_int_freq);
+ }
}
/*
}
if (call_rtc_interrupt) {
rtc_int_flag |= (RTC_IRQF | (RTC_NUM_INTS << 8));
- rtc_interrupt(rtc_int_flag, dev_id, regs);
+ rtc_interrupt(rtc_int_flag, dev_id);
}
return IRQ_HANDLED;
}
projects / linux-drm-fsl-dcu.git / blobdiff