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diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
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+/*
+ * Common time routines among all ppc machines.
+ *
+ * Written by Cort Dougan (cort@cs.nmt.edu) to merge
+ * Paul Mackerras' version and mine for PReP and Pmac.
+ * MPC8xx/MBX changes by Dan Malek (dmalek@jlc.net).
+ * Converted for 64-bit by Mike Corrigan (mikejc@us.ibm.com)
+ *
+ * First round of bugfixes by Gabriel Paubert (paubert@iram.es)
+ * to make clock more stable (2.4.0-test5). The only thing
+ * that this code assumes is that the timebases have been synchronized
+ * by firmware on SMP and are never stopped (never do sleep
+ * on SMP then, nap and doze are OK).
+ *
+ * Speeded up do_gettimeofday by getting rid of references to
+ * xtime (which required locks for consistency). (mikejc@us.ibm.com)
+ *
+ * TODO (not necessarily in this file):
+ * - improve precision and reproducibility of timebase frequency
+ * measurement at boot time. (for iSeries, we calibrate the timebase
+ * against the Titan chip's clock.)
+ * - for astronomical applications: add a new function to get
+ * non ambiguous timestamps even around leap seconds. This needs
+ * a new timestamp format and a good name.
+ *
+ * 1997-09-10 Updated NTP code according to technical memorandum Jan '96
+ * "A Kernel Model for Precision Timekeeping" by Dave Mills
+ *
+ * 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.
+ */
+
+#include <linux/errno.h>
+#include <linux/export.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/param.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/timex.h>
+#include <linux/kernel_stat.h>
+#include <linux/time.h>
+#include <linux/init.h>
+#include <linux/profile.h>
+#include <linux/cpu.h>
+#include <linux/security.h>
+#include <linux/percpu.h>
+#include <linux/rtc.h>
+#include <linux/jiffies.h>
+#include <linux/posix-timers.h>
+#include <linux/irq.h>
+#include <linux/delay.h>
+#include <linux/irq_work.h>
+#include <asm/trace.h>
+
+#include <asm/io.h>
+#include <asm/processor.h>
+#include <asm/nvram.h>
+#include <asm/cache.h>
+#include <asm/machdep.h>
+#include <asm/uaccess.h>
+#include <asm/time.h>
+#include <asm/prom.h>
+#include <asm/irq.h>
+#include <asm/div64.h>
+#include <asm/smp.h>
+#include <asm/vdso_datapage.h>
+#include <asm/firmware.h>
+#include <asm/cputime.h>
+#ifdef CONFIG_PPC_ISERIES
+#include <asm/iseries/it_lp_queue.h>
+#include <asm/iseries/hv_call_xm.h>
+#endif
+
+/* powerpc clocksource/clockevent code */
+
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+
+static cycle_t rtc_read(struct clocksource *);
+static struct clocksource clocksource_rtc = {
+ .name = "rtc",
+ .rating = 400,
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+ .mask = CLOCKSOURCE_MASK(64),
+ .read = rtc_read,
+};
+
+static cycle_t timebase_read(struct clocksource *);
+static struct clocksource clocksource_timebase = {
+ .name = "timebase",
+ .rating = 400,
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+ .mask = CLOCKSOURCE_MASK(64),
+ .read = timebase_read,
+};
+
+#define DECREMENTER_MAX 0x7fffffff
+
+static int decrementer_set_next_event(unsigned long evt,
+ struct clock_event_device *dev);
+static void decrementer_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *dev);
+
+static struct clock_event_device decrementer_clockevent = {
+ .name = "decrementer",
+ .rating = 200,
+ .irq = 0,
+ .set_next_event = decrementer_set_next_event,
+ .set_mode = decrementer_set_mode,
+ .features = CLOCK_EVT_FEAT_ONESHOT,
+};
+
+DEFINE_PER_CPU(u64, decrementers_next_tb);
+static DEFINE_PER_CPU(struct clock_event_device, decrementers);
+
+#ifdef CONFIG_PPC_ISERIES
+static unsigned long __initdata iSeries_recal_titan;
+static signed long __initdata iSeries_recal_tb;
+
+/* Forward declaration is only needed for iSereis compiles */
+static void __init clocksource_init(void);
+#endif
+
+#define XSEC_PER_SEC (1024*1024)
+
+#ifdef CONFIG_PPC64
+#define SCALE_XSEC(xsec, max) (((xsec) * max) / XSEC_PER_SEC)
+#else
+/* compute ((xsec << 12) * max) >> 32 */
+#define SCALE_XSEC(xsec, max) mulhwu((xsec) << 12, max)
+#endif
+
+unsigned long tb_ticks_per_jiffy;
+unsigned long tb_ticks_per_usec = 100; /* sane default */
+EXPORT_SYMBOL(tb_ticks_per_usec);
+unsigned long tb_ticks_per_sec;
+EXPORT_SYMBOL(tb_ticks_per_sec); /* for cputime_t conversions */
+
+DEFINE_SPINLOCK(rtc_lock);
+EXPORT_SYMBOL_GPL(rtc_lock);
+
+static u64 tb_to_ns_scale __read_mostly;
+static unsigned tb_to_ns_shift __read_mostly;
+static u64 boot_tb __read_mostly;
+
+extern struct timezone sys_tz;
+static long timezone_offset;
+
+unsigned long ppc_proc_freq;
+EXPORT_SYMBOL_GPL(ppc_proc_freq);
+unsigned long ppc_tb_freq;
+EXPORT_SYMBOL_GPL(ppc_tb_freq);
+
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+/*
+ * Factors for converting from cputime_t (timebase ticks) to
+ * jiffies, microseconds, seconds, and clock_t (1/USER_HZ seconds).
+ * These are all stored as 0.64 fixed-point binary fractions.
+ */
+u64 __cputime_jiffies_factor;
+EXPORT_SYMBOL(__cputime_jiffies_factor);
+u64 __cputime_usec_factor;
+EXPORT_SYMBOL(__cputime_usec_factor);
+u64 __cputime_sec_factor;
+EXPORT_SYMBOL(__cputime_sec_factor);
+u64 __cputime_clockt_factor;
+EXPORT_SYMBOL(__cputime_clockt_factor);
+DEFINE_PER_CPU(unsigned long, cputime_last_delta);
+DEFINE_PER_CPU(unsigned long, cputime_scaled_last_delta);
+
+cputime_t cputime_one_jiffy;
+
+void (*dtl_consumer)(struct dtl_entry *, u64);
+
+static void calc_cputime_factors(void)
+{
+ struct div_result res;
+
+ div128_by_32(HZ, 0, tb_ticks_per_sec, &res);
+ __cputime_jiffies_factor = res.result_low;
+ div128_by_32(1000000, 0, tb_ticks_per_sec, &res);
+ __cputime_usec_factor = res.result_low;
+ div128_by_32(1, 0, tb_ticks_per_sec, &res);
+ __cputime_sec_factor = res.result_low;
+ div128_by_32(USER_HZ, 0, tb_ticks_per_sec, &res);
+ __cputime_clockt_factor = res.result_low;
+}
+
+/*
+ * Read the SPURR on systems that have it, otherwise the PURR,
+ * or if that doesn't exist return the timebase value passed in.
+ */
+static u64 read_spurr(u64 tb)
+{
+ if (cpu_has_feature(CPU_FTR_SPURR))
+ return mfspr(SPRN_SPURR);
+ if (cpu_has_feature(CPU_FTR_PURR))
+ return mfspr(SPRN_PURR);
+ return tb;
+}
+
+#ifdef CONFIG_PPC_SPLPAR
+
+/*
+ * Scan the dispatch trace log and count up the stolen time.
+ * Should be called with interrupts disabled.
+ */
+static u64 scan_dispatch_log(u64 stop_tb)
+{
+ u64 i = local_paca->dtl_ridx;
+ struct dtl_entry *dtl = local_paca->dtl_curr;
+ struct dtl_entry *dtl_end = local_paca->dispatch_log_end;
+ struct lppaca *vpa = local_paca->lppaca_ptr;
+ u64 tb_delta;
+ u64 stolen = 0;
+ u64 dtb;
+
+ if (!dtl)
+ return 0;
+
+ if (i == vpa->dtl_idx)
+ return 0;
+ while (i < vpa->dtl_idx) {
+ if (dtl_consumer)
+ dtl_consumer(dtl, i);
+ dtb = dtl->timebase;
+ tb_delta = dtl->enqueue_to_dispatch_time +
+ dtl->ready_to_enqueue_time;
+ barrier();
+ if (i + N_DISPATCH_LOG < vpa->dtl_idx) {
+ /* buffer has overflowed */
+ i = vpa->dtl_idx - N_DISPATCH_LOG;
+ dtl = local_paca->dispatch_log + (i % N_DISPATCH_LOG);
+ continue;
+ }
+ if (dtb > stop_tb)
+ break;
+ stolen += tb_delta;
+ ++i;
+ ++dtl;
+ if (dtl == dtl_end)
+ dtl = local_paca->dispatch_log;
+ }
+ local_paca->dtl_ridx = i;
+ local_paca->dtl_curr = dtl;
+ return stolen;
+}
+
+/*
+ * Accumulate stolen time by scanning the dispatch trace log.
+ * Called on entry from user mode.
+ */
+void accumulate_stolen_time(void)
+{
+ u64 sst, ust;
+
+ u8 save_soft_enabled = local_paca->soft_enabled;
+ u8 save_hard_enabled = local_paca->hard_enabled;
+
+ /* We are called early in the exception entry, before
+ * soft/hard_enabled are sync'ed to the expected state
+ * for the exception. We are hard disabled but the PACA
+ * needs to reflect that so various debug stuff doesn't
+ * complain
+ */
+ local_paca->soft_enabled = 0;
+ local_paca->hard_enabled = 0;
+
+ sst = scan_dispatch_log(local_paca->starttime_user);
+ ust = scan_dispatch_log(local_paca->starttime);
+ local_paca->system_time -= sst;
+ local_paca->user_time -= ust;
+ local_paca->stolen_time += ust + sst;
+
+ local_paca->soft_enabled = save_soft_enabled;
+ local_paca->hard_enabled = save_hard_enabled;
+}
+
+static inline u64 calculate_stolen_time(u64 stop_tb)
+{
+ u64 stolen = 0;
+
+ if (get_paca()->dtl_ridx != get_paca()->lppaca_ptr->dtl_idx) {
+ stolen = scan_dispatch_log(stop_tb);
+ get_paca()->system_time -= stolen;
+ }
+
+ stolen += get_paca()->stolen_time;
+ get_paca()->stolen_time = 0;
+ return stolen;
+}
+
+#else /* CONFIG_PPC_SPLPAR */
+static inline u64 calculate_stolen_time(u64 stop_tb)
+{
+ return 0;
+}
+
+#endif /* CONFIG_PPC_SPLPAR */
+
+/*
+ * Account time for a transition between system, hard irq
+ * or soft irq state.
+ */
+void account_system_vtime(struct task_struct *tsk)
+{
+ u64 now, nowscaled, delta, deltascaled;
+ unsigned long flags;
+ u64 stolen, udelta, sys_scaled, user_scaled;
+
+ local_irq_save(flags);
+ now = mftb();
+ nowscaled = read_spurr(now);
+ get_paca()->system_time += now - get_paca()->starttime;
+ get_paca()->starttime = now;
+ deltascaled = nowscaled - get_paca()->startspurr;
+ get_paca()->startspurr = nowscaled;
+
+ stolen = calculate_stolen_time(now);
+
+ delta = get_paca()->system_time;
+ get_paca()->system_time = 0;
+ udelta = get_paca()->user_time - get_paca()->utime_sspurr;
+ get_paca()->utime_sspurr = get_paca()->user_time;
+
+ /*
+ * Because we don't read the SPURR on every kernel entry/exit,
+ * deltascaled includes both user and system SPURR ticks.
+ * Apportion these ticks to system SPURR ticks and user
+ * SPURR ticks in the same ratio as the system time (delta)
+ * and user time (udelta) values obtained from the timebase
+ * over the same interval. The system ticks get accounted here;
+ * the user ticks get saved up in paca->user_time_scaled to be
+ * used by account_process_tick.
+ */
+ sys_scaled = delta;
+ user_scaled = udelta;
+ if (deltascaled != delta + udelta) {
+ if (udelta) {
+ sys_scaled = deltascaled * delta / (delta + udelta);
+ user_scaled = deltascaled - sys_scaled;
+ } else {
+ sys_scaled = deltascaled;
+ }
+ }
+ get_paca()->user_time_scaled += user_scaled;
+
+ if (in_interrupt() || idle_task(smp_processor_id()) != tsk) {
+ account_system_time(tsk, 0, delta, sys_scaled);
+ if (stolen)
+ account_steal_time(stolen);
+ } else {
+ account_idle_time(delta + stolen);
+ }
+ local_irq_restore(flags);
+}
+EXPORT_SYMBOL_GPL(account_system_vtime);
+
+/*
+ * Transfer the user and system times accumulated in the paca
+ * by the exception entry and exit code to the generic process
+ * user and system time records.
+ * Must be called with interrupts disabled.
+ * Assumes that account_system_vtime() has been called recently
+ * (i.e. since the last entry from usermode) so that
+ * get_paca()->user_time_scaled is up to date.
+ */
+void account_process_tick(struct task_struct *tsk, int user_tick)
+{
+ cputime_t utime, utimescaled;
+
+ utime = get_paca()->user_time;
+ utimescaled = get_paca()->user_time_scaled;
+ get_paca()->user_time = 0;
+ get_paca()->user_time_scaled = 0;
+ get_paca()->utime_sspurr = 0;
+ account_user_time(tsk, utime, utimescaled);
+}
+
+#else /* ! CONFIG_VIRT_CPU_ACCOUNTING */
+#define calc_cputime_factors()
+#endif
+
+void __delay(unsigned long loops)
+{
+ unsigned long start;
+ int diff;
+
+ if (__USE_RTC()) {
+ start = get_rtcl();
+ do {
+ /* the RTCL register wraps at 1000000000 */
+ diff = get_rtcl() - start;
+ if (diff < 0)
+ diff += 1000000000;
+ } while (diff < loops);
+ } else {
+ start = get_tbl();
+ while (get_tbl() - start < loops)
+ HMT_low();
+ HMT_medium();
+ }
+}
+EXPORT_SYMBOL(__delay);
+
+void udelay(unsigned long usecs)
+{
+ __delay(tb_ticks_per_usec * usecs);
+}
+EXPORT_SYMBOL(udelay);
+
+#ifdef CONFIG_SMP
+unsigned long profile_pc(struct pt_regs *regs)
+{
+ unsigned long pc = instruction_pointer(regs);
+
+ if (in_lock_functions(pc))
+ return regs->link;
+
+ return pc;
+}
+EXPORT_SYMBOL(profile_pc);
+#endif
+
+#ifdef CONFIG_PPC_ISERIES
+
+/*
+ * This function recalibrates the timebase based on the 49-bit time-of-day
+ * value in the Titan chip. The Titan is much more accurate than the value
+ * returned by the service processor for the timebase frequency.
+ */
+
+static int __init iSeries_tb_recal(void)
+{
+ unsigned long titan, tb;
+
+ /* Make sure we only run on iSeries */
+ if (!firmware_has_feature(FW_FEATURE_ISERIES))
+ return -ENODEV;
+
+ tb = get_tb();
+ titan = HvCallXm_loadTod();
+ if ( iSeries_recal_titan ) {
+ unsigned long tb_ticks = tb - iSeries_recal_tb;
+ unsigned long titan_usec = (titan - iSeries_recal_titan) >> 12;
+ unsigned long new_tb_ticks_per_sec = (tb_ticks * USEC_PER_SEC)/titan_usec;
+ unsigned long new_tb_ticks_per_jiffy =
+ DIV_ROUND_CLOSEST(new_tb_ticks_per_sec, HZ);
+ long tick_diff = new_tb_ticks_per_jiffy - tb_ticks_per_jiffy;
+ char sign = '+';
+ /* make sure tb_ticks_per_sec and tb_ticks_per_jiffy are consistent */
+ new_tb_ticks_per_sec = new_tb_ticks_per_jiffy * HZ;
+
+ if ( tick_diff < 0 ) {
+ tick_diff = -tick_diff;
+ sign = '-';
+ }
+ if ( tick_diff ) {
+ if ( tick_diff < tb_ticks_per_jiffy/25 ) {
+ printk( "Titan recalibrate: new tb_ticks_per_jiffy = %lu (%c%ld)\n",
+ new_tb_ticks_per_jiffy, sign, tick_diff );
+ tb_ticks_per_jiffy = new_tb_ticks_per_jiffy;
+ tb_ticks_per_sec = new_tb_ticks_per_sec;
+ calc_cputime_factors();
+ vdso_data->tb_ticks_per_sec = tb_ticks_per_sec;
+ setup_cputime_one_jiffy();
+ }
+ else {
+ printk( "Titan recalibrate: FAILED (difference > 4 percent)\n"
+ " new tb_ticks_per_jiffy = %lu\n"
+ " old tb_ticks_per_jiffy = %lu\n",
+ new_tb_ticks_per_jiffy, tb_ticks_per_jiffy );
+ }
+ }
+ }
+ iSeries_recal_titan = titan;
+ iSeries_recal_tb = tb;
+
+ /* Called here as now we know accurate values for the timebase */
+ clocksource_init();
+ return 0;
+}
+late_initcall(iSeries_tb_recal);
+
+/* Called from platform early init */
+void __init iSeries_time_init_early(void)
+{
+ iSeries_recal_tb = get_tb();
+ iSeries_recal_titan = HvCallXm_loadTod();
+}
+#endif /* CONFIG_PPC_ISERIES */
+
+#ifdef CONFIG_IRQ_WORK
+
+/*
+ * 64-bit uses a byte in the PACA, 32-bit uses a per-cpu variable...
+ */
+#ifdef CONFIG_PPC64
+static inline unsigned long test_irq_work_pending(void)
+{
+ unsigned long x;
+
+ asm volatile("lbz %0,%1(13)"
+ : "=r" (x)
+ : "i" (offsetof(struct paca_struct, irq_work_pending)));
+ return x;
+}
+
+static inline void set_irq_work_pending_flag(void)
+{
+ asm volatile("stb %0,%1(13)" : :
+ "r" (1),
+ "i" (offsetof(struct paca_struct, irq_work_pending)));
+}
+
+static inline void clear_irq_work_pending(void)
+{
+ asm volatile("stb %0,%1(13)" : :
+ "r" (0),
+ "i" (offsetof(struct paca_struct, irq_work_pending)));
+}
+
+#else /* 32-bit */
+
+DEFINE_PER_CPU(u8, irq_work_pending);
+
+#define set_irq_work_pending_flag() __get_cpu_var(irq_work_pending) = 1
+#define test_irq_work_pending() __get_cpu_var(irq_work_pending)
+#define clear_irq_work_pending() __get_cpu_var(irq_work_pending) = 0
+
+#endif /* 32 vs 64 bit */
+
+void arch_irq_work_raise(void)
+{
+ preempt_disable();
+ set_irq_work_pending_flag();
+ set_dec(1);
+ preempt_enable();
+}
+
+#else /* CONFIG_IRQ_WORK */
+
+#define test_irq_work_pending() 0
+#define clear_irq_work_pending()
+
+#endif /* CONFIG_IRQ_WORK */
+
+/*
+ * For iSeries shared processors, we have to let the hypervisor
+ * set the hardware decrementer. We set a virtual decrementer
+ * in the lppaca and call the hypervisor if the virtual
+ * decrementer is less than the current value in the hardware
+ * decrementer. (almost always the new decrementer value will
+ * be greater than the current hardware decementer so the hypervisor
+ * call will not be needed)
+ */
+
+/*
+ * timer_interrupt - gets called when the decrementer overflows,
+ * with interrupts disabled.
+ */
+void timer_interrupt(struct pt_regs * regs)
+{
+ struct pt_regs *old_regs;
+ u64 *next_tb = &__get_cpu_var(decrementers_next_tb);
+ struct clock_event_device *evt = &__get_cpu_var(decrementers);
+
+ /* Ensure a positive value is written to the decrementer, or else
+ * some CPUs will continue to take decrementer exceptions.
+ */
+ set_dec(DECREMENTER_MAX);
+
+ /* Some implementations of hotplug will get timer interrupts while
+ * offline, just ignore these
+ */
+ if (!cpu_online(smp_processor_id()))
+ return;
+
+ trace_timer_interrupt_entry(regs);
+
+ __get_cpu_var(irq_stat).timer_irqs++;
+
+#if defined(CONFIG_PPC32) && defined(CONFIG_PMAC)
+ if (atomic_read(&ppc_n_lost_interrupts) != 0)
+ do_IRQ(regs);
+#endif
+
+ old_regs = set_irq_regs(regs);
+ irq_enter();
+
+ if (test_irq_work_pending()) {
+ clear_irq_work_pending();
+ irq_work_run();
+ }
+
+#ifdef CONFIG_PPC_ISERIES
+ if (firmware_has_feature(FW_FEATURE_ISERIES))
+ get_lppaca()->int_dword.fields.decr_int = 0;
+#endif
+
+ *next_tb = ~(u64)0;
+ if (evt->event_handler)
+ evt->event_handler(evt);
+
+#ifdef CONFIG_PPC_ISERIES
+ if (firmware_has_feature(FW_FEATURE_ISERIES) && hvlpevent_is_pending())
+ process_hvlpevents();
+#endif
+
+#ifdef CONFIG_PPC64
+ /* collect purr register values often, for accurate calculations */
+ if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
+ struct cpu_usage *cu = &__get_cpu_var(cpu_usage_array);
+ cu->current_tb = mfspr(SPRN_PURR);
+ }
+#endif
+
+ irq_exit();
+ set_irq_regs(old_regs);
+
+ trace_timer_interrupt_exit(regs);
+}
+
+#ifdef CONFIG_SUSPEND
+static void generic_suspend_disable_irqs(void)
+{
+ /* Disable the decrementer, so that it doesn't interfere
+ * with suspending.
+ */
+
+ set_dec(DECREMENTER_MAX);
+ local_irq_disable();
+ set_dec(DECREMENTER_MAX);
+}
+
+static void generic_suspend_enable_irqs(void)
+{
+ local_irq_enable();
+}
+
+/* Overrides the weak version in kernel/power/main.c */
+void arch_suspend_disable_irqs(void)
+{
+ if (ppc_md.suspend_disable_irqs)
+ ppc_md.suspend_disable_irqs();
+ generic_suspend_disable_irqs();
+}
+
+/* Overrides the weak version in kernel/power/main.c */
+void arch_suspend_enable_irqs(void)
+{
+ generic_suspend_enable_irqs();
+ if (ppc_md.suspend_enable_irqs)
+ ppc_md.suspend_enable_irqs();
+}
+#endif
+
+/*
+ * Scheduler clock - returns current time in nanosec units.
+ *
+ * Note: mulhdu(a, b) (multiply high double unsigned) returns
+ * the high 64 bits of a * b, i.e. (a * b) >> 64, where a and b
+ * are 64-bit unsigned numbers.
+ */
+unsigned long long sched_clock(void)
+{
+ if (__USE_RTC())
+ return get_rtc();
+ return mulhdu(get_tb() - boot_tb, tb_to_ns_scale) << tb_to_ns_shift;
+}
+
+static int __init get_freq(char *name, int cells, unsigned long *val)
+{
+ struct device_node *cpu;
+ const unsigned int *fp;
+ int found = 0;
+
+ /* The cpu node should have timebase and clock frequency properties */
+ cpu = of_find_node_by_type(NULL, "cpu");
+
+ if (cpu) {
+ fp = of_get_property(cpu, name, NULL);
+ if (fp) {
+ found = 1;
+ *val = of_read_ulong(fp, cells);
+ }
+
+ of_node_put(cpu);
+ }
+
+ return found;
+}
+
+/* should become __cpuinit when secondary_cpu_time_init also is */
+void start_cpu_decrementer(void)
+{
+#if defined(CONFIG_BOOKE) || defined(CONFIG_40x)
+ /* Clear any pending timer interrupts */
+ mtspr(SPRN_TSR, TSR_ENW | TSR_WIS | TSR_DIS | TSR_FIS);
+
+ /* Enable decrementer interrupt */
+ mtspr(SPRN_TCR, TCR_DIE);
+#endif /* defined(CONFIG_BOOKE) || defined(CONFIG_40x) */
+}
+
+void __init generic_calibrate_decr(void)
+{
+ ppc_tb_freq = DEFAULT_TB_FREQ; /* hardcoded default */
+
+ if (!get_freq("ibm,extended-timebase-frequency", 2, &ppc_tb_freq) &&
+ !get_freq("timebase-frequency", 1, &ppc_tb_freq)) {
+
+ printk(KERN_ERR "WARNING: Estimating decrementer frequency "
+ "(not found)\n");
+ }
+
+ ppc_proc_freq = DEFAULT_PROC_FREQ; /* hardcoded default */
+
+ if (!get_freq("ibm,extended-clock-frequency", 2, &ppc_proc_freq) &&
+ !get_freq("clock-frequency", 1, &ppc_proc_freq)) {
+
+ printk(KERN_ERR "WARNING: Estimating processor frequency "
+ "(not found)\n");
+ }
+}
+
+int update_persistent_clock(struct timespec now)
+{
+ struct rtc_time tm;
+
+ if (!ppc_md.set_rtc_time)
+ return 0;
+
+ to_tm(now.tv_sec + 1 + timezone_offset, &tm);
+ tm.tm_year -= 1900;
+ tm.tm_mon -= 1;
+
+ return ppc_md.set_rtc_time(&tm);
+}
+
+static void __read_persistent_clock(struct timespec *ts)
+{
+ struct rtc_time tm;
+ static int first = 1;
+
+ ts->tv_nsec = 0;
+ /* XXX this is a litle fragile but will work okay in the short term */
+ if (first) {
+ first = 0;
+ if (ppc_md.time_init)
+ timezone_offset = ppc_md.time_init();
+
+ /* get_boot_time() isn't guaranteed to be safe to call late */
+ if (ppc_md.get_boot_time) {
+ ts->tv_sec = ppc_md.get_boot_time() - timezone_offset;
+ return;
+ }
+ }
+ if (!ppc_md.get_rtc_time) {
+ ts->tv_sec = 0;
+ return;
+ }
+ ppc_md.get_rtc_time(&tm);
+
+ ts->tv_sec = mktime(tm.tm_year+1900, tm.tm_mon+1, tm.tm_mday,
+ tm.tm_hour, tm.tm_min, tm.tm_sec);
+}
+
+void read_persistent_clock(struct timespec *ts)
+{
+ __read_persistent_clock(ts);
+
+ /* Sanitize it in case real time clock is set below EPOCH */
+ if (ts->tv_sec < 0) {
+ ts->tv_sec = 0;
+ ts->tv_nsec = 0;
+ }
+
+}
+
+/* clocksource code */
+static cycle_t rtc_read(struct clocksource *cs)
+{
+ return (cycle_t)get_rtc();
+}
+
+static cycle_t timebase_read(struct clocksource *cs)
+{
+ return (cycle_t)get_tb();
+}
+
+void update_vsyscall(struct timespec *wall_time, struct timespec *wtm,
+ struct clocksource *clock, u32 mult)
+{
+ u64 new_tb_to_xs, new_stamp_xsec;
+ u32 frac_sec;
+
+ if (clock != &clocksource_timebase)
+ return;
+
+ /* Make userspace gettimeofday spin until we're done. */
+ ++vdso_data->tb_update_count;
+ smp_mb();
+
+ /* 19342813113834067 ~= 2^(20+64) / 1e9 */
+ new_tb_to_xs = (u64) mult * (19342813113834067ULL >> clock->shift);
+ new_stamp_xsec = (u64) wall_time->tv_nsec * XSEC_PER_SEC;
+ do_div(new_stamp_xsec, 1000000000);
+ new_stamp_xsec += (u64) wall_time->tv_sec * XSEC_PER_SEC;
+
+ BUG_ON(wall_time->tv_nsec >= NSEC_PER_SEC);
+ /* this is tv_nsec / 1e9 as a 0.32 fraction */
+ frac_sec = ((u64) wall_time->tv_nsec * 18446744073ULL) >> 32;
+
+ /*
+ * tb_update_count is used to allow the userspace gettimeofday code
+ * to assure itself that it sees a consistent view of the tb_to_xs and
+ * stamp_xsec variables. It reads the tb_update_count, then reads
+ * tb_to_xs and stamp_xsec and then reads tb_update_count again. If
+ * the two values of tb_update_count match and are even then the
+ * tb_to_xs and stamp_xsec values are consistent. If not, then it
+ * loops back and reads them again until this criteria is met.
+ * We expect the caller to have done the first increment of
+ * vdso_data->tb_update_count already.
+ */
+ vdso_data->tb_orig_stamp = clock->cycle_last;
+ vdso_data->stamp_xsec = new_stamp_xsec;
+ vdso_data->tb_to_xs = new_tb_to_xs;
+ vdso_data->wtom_clock_sec = wtm->tv_sec;
+ vdso_data->wtom_clock_nsec = wtm->tv_nsec;
+ vdso_data->stamp_xtime = *wall_time;
+ vdso_data->stamp_sec_fraction = frac_sec;
+ smp_wmb();
+ ++(vdso_data->tb_update_count);
+}
+
+void update_vsyscall_tz(void)
+{
+ /* Make userspace gettimeofday spin until we're done. */
+ ++vdso_data->tb_update_count;
+ smp_mb();
+ vdso_data->tz_minuteswest = sys_tz.tz_minuteswest;
+ vdso_data->tz_dsttime = sys_tz.tz_dsttime;
+ smp_mb();
+ ++vdso_data->tb_update_count;
+}
+
+static void __init clocksource_init(void)
+{
+ struct clocksource *clock;
+
+ if (__USE_RTC())
+ clock = &clocksource_rtc;
+ else
+ clock = &clocksource_timebase;
+
+ if (clocksource_register_hz(clock, tb_ticks_per_sec)) {
+ printk(KERN_ERR "clocksource: %s is already registered\n",
+ clock->name);
+ return;
+ }
+
+ printk(KERN_INFO "clocksource: %s mult[%x] shift[%d] registered\n",
+ clock->name, clock->mult, clock->shift);
+}
+
+static int decrementer_set_next_event(unsigned long evt,
+ struct clock_event_device *dev)
+{
+ __get_cpu_var(decrementers_next_tb) = get_tb_or_rtc() + evt;
+ set_dec(evt);
+ return 0;
+}
+
+static void decrementer_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *dev)
+{
+ if (mode != CLOCK_EVT_MODE_ONESHOT)
+ decrementer_set_next_event(DECREMENTER_MAX, dev);
+}
+
+static void register_decrementer_clockevent(int cpu)
+{
+ struct clock_event_device *dec = &per_cpu(decrementers, cpu);
+
+ *dec = decrementer_clockevent;
+ dec->cpumask = cpumask_of(cpu);
+
+ printk_once(KERN_DEBUG "clockevent: %s mult[%x] shift[%d] cpu[%d]\n",
+ dec->name, dec->mult, dec->shift, cpu);
+
+ clockevents_register_device(dec);
+}
+
+static void __init init_decrementer_clockevent(void)
+{
+ int cpu = smp_processor_id();
+
+ clockevents_calc_mult_shift(&decrementer_clockevent, ppc_tb_freq, 4);
+
+ decrementer_clockevent.max_delta_ns =
+ clockevent_delta2ns(DECREMENTER_MAX, &decrementer_clockevent);
+ decrementer_clockevent.min_delta_ns =
+ clockevent_delta2ns(2, &decrementer_clockevent);
+
+ register_decrementer_clockevent(cpu);
+}
+
+void secondary_cpu_time_init(void)
+{
+ /* Start the decrementer on CPUs that have manual control
+ * such as BookE
+ */
+ start_cpu_decrementer();
+
+ /* FIME: Should make unrelatred change to move snapshot_timebase
+ * call here ! */
+ register_decrementer_clockevent(smp_processor_id());
+}
+
+/* This function is only called on the boot processor */
+void __init time_init(void)
+{
+ struct div_result res;
+ u64 scale;
+ unsigned shift;
+
+ if (__USE_RTC()) {
+ /* 601 processor: dec counts down by 128 every 128ns */
+ ppc_tb_freq = 1000000000;
+ } else {
+ /* Normal PowerPC with timebase register */
+ ppc_md.calibrate_decr();
+ printk(KERN_DEBUG "time_init: decrementer frequency = %lu.%.6lu MHz\n",
+ ppc_tb_freq / 1000000, ppc_tb_freq % 1000000);
+ printk(KERN_DEBUG "time_init: processor frequency = %lu.%.6lu MHz\n",
+ ppc_proc_freq / 1000000, ppc_proc_freq % 1000000);
+ }
+
+ tb_ticks_per_jiffy = ppc_tb_freq / HZ;
+ tb_ticks_per_sec = ppc_tb_freq;
+ tb_ticks_per_usec = ppc_tb_freq / 1000000;
+ calc_cputime_factors();
+ setup_cputime_one_jiffy();
+
+ /*
+ * Compute scale factor for sched_clock.
+ * The calibrate_decr() function has set tb_ticks_per_sec,
+ * which is the timebase frequency.
+ * We compute 1e9 * 2^64 / tb_ticks_per_sec and interpret
+ * the 128-bit result as a 64.64 fixed-point number.
+ * We then shift that number right until it is less than 1.0,
+ * giving us the scale factor and shift count to use in
+ * sched_clock().
+ */
+ div128_by_32(1000000000, 0, tb_ticks_per_sec, &res);
+ scale = res.result_low;
+ for (shift = 0; res.result_high != 0; ++shift) {
+ scale = (scale >> 1) | (res.result_high << 63);
+ res.result_high >>= 1;
+ }
+ tb_to_ns_scale = scale;
+ tb_to_ns_shift = shift;
+ /* Save the current timebase to pretty up CONFIG_PRINTK_TIME */
+ boot_tb = get_tb_or_rtc();
+
+ /* If platform provided a timezone (pmac), we correct the time */
+ if (timezone_offset) {
+ sys_tz.tz_minuteswest = -timezone_offset / 60;
+ sys_tz.tz_dsttime = 0;
+ }
+
+ vdso_data->tb_update_count = 0;
+ vdso_data->tb_ticks_per_sec = tb_ticks_per_sec;
+
+ /* Start the decrementer on CPUs that have manual control
+ * such as BookE
+ */
+ start_cpu_decrementer();
+
+ /* Register the clocksource, if we're not running on iSeries */
+ if (!firmware_has_feature(FW_FEATURE_ISERIES))
+ clocksource_init();
+
+ init_decrementer_clockevent();
+}
+
+
+#define FEBRUARY 2
+#define STARTOFTIME 1970
+#define SECDAY 86400L
+#define SECYR (SECDAY * 365)
+#define leapyear(year) ((year) % 4 == 0 && \
+ ((year) % 100 != 0 || (year) % 400 == 0))
+#define days_in_year(a) (leapyear(a) ? 366 : 365)
+#define days_in_month(a) (month_days[(a) - 1])
+
+static int month_days[12] = {
+ 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
+};
+
+/*
+ * This only works for the Gregorian calendar - i.e. after 1752 (in the UK)
+ */
+void GregorianDay(struct rtc_time * tm)
+{
+ int leapsToDate;
+ int lastYear;
+ int day;
+ int MonthOffset[] = { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 };
+
+ lastYear = tm->tm_year - 1;
+
+ /*
+ * Number of leap corrections to apply up to end of last year
+ */
+ leapsToDate = lastYear / 4 - lastYear / 100 + lastYear / 400;
+
+ /*
+ * This year is a leap year if it is divisible by 4 except when it is
+ * divisible by 100 unless it is divisible by 400
+ *
+ * e.g. 1904 was a leap year, 1900 was not, 1996 is, and 2000 was
+ */
+ day = tm->tm_mon > 2 && leapyear(tm->tm_year);
+
+ day += lastYear*365 + leapsToDate + MonthOffset[tm->tm_mon-1] +
+ tm->tm_mday;
+
+ tm->tm_wday = day % 7;
+}
+
+void to_tm(int tim, struct rtc_time * tm)
+{
+ register int i;
+ register long hms, day;
+
+ day = tim / SECDAY;
+ hms = tim % SECDAY;
+
+ /* Hours, minutes, seconds are easy */
+ tm->tm_hour = hms / 3600;
+ tm->tm_min = (hms % 3600) / 60;
+ tm->tm_sec = (hms % 3600) % 60;
+
+ /* Number of years in days */
+ for (i = STARTOFTIME; day >= days_in_year(i); i++)
+ day -= days_in_year(i);
+ tm->tm_year = i;
+
+ /* Number of months in days left */
+ if (leapyear(tm->tm_year))
+ days_in_month(FEBRUARY) = 29;
+ for (i = 1; day >= days_in_month(i); i++)
+ day -= days_in_month(i);
+ days_in_month(FEBRUARY) = 28;
+ tm->tm_mon = i;
+
+ /* Days are what is left over (+1) from all that. */
+ tm->tm_mday = day + 1;
+
+ /*
+ * Determine the day of week
+ */
+ GregorianDay(tm);
+}
+
+/*
+ * Divide a 128-bit dividend by a 32-bit divisor, leaving a 128 bit
+ * result.
+ */
+void div128_by_32(u64 dividend_high, u64 dividend_low,
+ unsigned divisor, struct div_result *dr)
+{
+ unsigned long a, b, c, d;
+ unsigned long w, x, y, z;
+ u64 ra, rb, rc;
+
+ a = dividend_high >> 32;
+ b = dividend_high & 0xffffffff;
+ c = dividend_low >> 32;
+ d = dividend_low & 0xffffffff;
+
+ w = a / divisor;
+ ra = ((u64)(a - (w * divisor)) << 32) + b;
+
+ rb = ((u64) do_div(ra, divisor) << 32) + c;
+ x = ra;
+
+ rc = ((u64) do_div(rb, divisor) << 32) + d;
+ y = rb;
+
+ do_div(rc, divisor);
+ z = rc;
+
+ dr->result_high = ((u64)w << 32) + x;
+ dr->result_low = ((u64)y << 32) + z;
+
+}
+
+/* We don't need to calibrate delay, we use the CPU timebase for that */
+void calibrate_delay(void)
+{
+ /* Some generic code (such as spinlock debug) use loops_per_jiffy
+ * as the number of __delay(1) in a jiffy, so make it so
+ */
+ loops_per_jiffy = tb_ticks_per_jiffy;
+}
+
+static int __init rtc_init(void)
+{
+ struct platform_device *pdev;
+
+ if (!ppc_md.get_rtc_time)
+ return -ENODEV;
+
+ pdev = platform_device_register_simple("rtc-generic", -1, NULL, 0);
+ if (IS_ERR(pdev))
+ return PTR_ERR(pdev);
+
+ return 0;
+}
+
+module_init(rtc_init);