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941 lines
23 KiB
941 lines
23 KiB
// SPDX-License-Identifier: GPL-2.0 |
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/* |
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* Time of day based timer functions. |
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* |
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* S390 version |
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* Copyright IBM Corp. 1999, 2008 |
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* Author(s): Hartmut Penner ([email protected]), |
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* Martin Schwidefsky ([email protected]), |
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* Denis Joseph Barrow ([email protected],[email protected]) |
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* |
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* Derived from "arch/i386/kernel/time.c" |
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* Copyright (C) 1991, 1992, 1995 Linus Torvalds |
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*/ |
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|
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#define KMSG_COMPONENT "time" |
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#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt |
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|
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#include <linux/kernel_stat.h> |
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#include <linux/errno.h> |
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#include <linux/export.h> |
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#include <linux/sched.h> |
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#include <linux/sched/clock.h> |
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#include <linux/kernel.h> |
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#include <linux/param.h> |
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#include <linux/string.h> |
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#include <linux/mm.h> |
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#include <linux/interrupt.h> |
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#include <linux/cpu.h> |
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#include <linux/stop_machine.h> |
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#include <linux/time.h> |
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#include <linux/device.h> |
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#include <linux/delay.h> |
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#include <linux/init.h> |
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#include <linux/smp.h> |
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#include <linux/types.h> |
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#include <linux/profile.h> |
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#include <linux/timex.h> |
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#include <linux/notifier.h> |
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#include <linux/timekeeper_internal.h> |
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#include <linux/clockchips.h> |
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#include <linux/gfp.h> |
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#include <linux/kprobes.h> |
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#include <linux/uaccess.h> |
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#include <vdso/vsyscall.h> |
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#include <vdso/clocksource.h> |
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#include <vdso/helpers.h> |
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#include <asm/facility.h> |
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#include <asm/delay.h> |
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#include <asm/div64.h> |
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#include <asm/vdso.h> |
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#include <asm/irq.h> |
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#include <asm/irq_regs.h> |
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#include <asm/vtimer.h> |
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#include <asm/stp.h> |
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#include <asm/cio.h> |
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#include "entry.h" |
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|
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union tod_clock tod_clock_base __section(".data"); |
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EXPORT_SYMBOL_GPL(tod_clock_base); |
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u64 clock_comparator_max = -1ULL; |
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EXPORT_SYMBOL_GPL(clock_comparator_max); |
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|
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static DEFINE_PER_CPU(struct clock_event_device, comparators); |
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|
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ATOMIC_NOTIFIER_HEAD(s390_epoch_delta_notifier); |
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EXPORT_SYMBOL(s390_epoch_delta_notifier); |
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|
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unsigned char ptff_function_mask[16]; |
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|
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static unsigned long lpar_offset; |
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static unsigned long initial_leap_seconds; |
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static unsigned long tod_steering_end; |
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static long tod_steering_delta; |
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|
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/* |
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* Get time offsets with PTFF |
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*/ |
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void __init time_early_init(void) |
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{ |
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struct ptff_qto qto; |
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struct ptff_qui qui; |
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int cs; |
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|
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/* Initialize TOD steering parameters */ |
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tod_steering_end = tod_clock_base.tod; |
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for (cs = 0; cs < CS_BASES; cs++) |
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vdso_data[cs].arch_data.tod_steering_end = tod_steering_end; |
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|
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if (!test_facility(28)) |
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return; |
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ptff(&ptff_function_mask, sizeof(ptff_function_mask), PTFF_QAF); |
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|
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/* get LPAR offset */ |
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if (ptff_query(PTFF_QTO) && ptff(&qto, sizeof(qto), PTFF_QTO) == 0) |
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lpar_offset = qto.tod_epoch_difference; |
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|
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/* get initial leap seconds */ |
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if (ptff_query(PTFF_QUI) && ptff(&qui, sizeof(qui), PTFF_QUI) == 0) |
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initial_leap_seconds = (unsigned long) |
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((long) qui.old_leap * 4096000000L); |
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} |
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|
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/* |
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* Scheduler clock - returns current time in nanosec units. |
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*/ |
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unsigned long long notrace sched_clock(void) |
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{ |
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return tod_to_ns(get_tod_clock_monotonic()); |
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} |
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NOKPROBE_SYMBOL(sched_clock); |
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|
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static void ext_to_timespec64(union tod_clock *clk, struct timespec64 *xt) |
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{ |
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unsigned long rem, sec, nsec; |
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|
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sec = clk->us; |
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rem = do_div(sec, 1000000); |
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nsec = ((clk->sus + (rem << 12)) * 125) >> 9; |
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xt->tv_sec = sec; |
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xt->tv_nsec = nsec; |
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} |
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|
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void clock_comparator_work(void) |
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{ |
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struct clock_event_device *cd; |
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|
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S390_lowcore.clock_comparator = clock_comparator_max; |
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cd = this_cpu_ptr(&comparators); |
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cd->event_handler(cd); |
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} |
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|
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static int s390_next_event(unsigned long delta, |
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struct clock_event_device *evt) |
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{ |
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S390_lowcore.clock_comparator = get_tod_clock() + delta; |
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set_clock_comparator(S390_lowcore.clock_comparator); |
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return 0; |
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} |
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|
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/* |
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* Set up lowcore and control register of the current cpu to |
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* enable TOD clock and clock comparator interrupts. |
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*/ |
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void init_cpu_timer(void) |
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{ |
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struct clock_event_device *cd; |
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int cpu; |
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S390_lowcore.clock_comparator = clock_comparator_max; |
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set_clock_comparator(S390_lowcore.clock_comparator); |
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|
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cpu = smp_processor_id(); |
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cd = &per_cpu(comparators, cpu); |
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cd->name = "comparator"; |
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cd->features = CLOCK_EVT_FEAT_ONESHOT; |
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cd->mult = 16777; |
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cd->shift = 12; |
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cd->min_delta_ns = 1; |
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cd->min_delta_ticks = 1; |
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cd->max_delta_ns = LONG_MAX; |
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cd->max_delta_ticks = ULONG_MAX; |
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cd->rating = 400; |
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cd->cpumask = cpumask_of(cpu); |
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cd->set_next_event = s390_next_event; |
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clockevents_register_device(cd); |
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|
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/* Enable clock comparator timer interrupt. */ |
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__ctl_set_bit(0,11); |
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|
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/* Always allow the timing alert external interrupt. */ |
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__ctl_set_bit(0, 4); |
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} |
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static void clock_comparator_interrupt(struct ext_code ext_code, |
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unsigned int param32, |
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unsigned long param64) |
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{ |
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inc_irq_stat(IRQEXT_CLK); |
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if (S390_lowcore.clock_comparator == clock_comparator_max) |
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set_clock_comparator(S390_lowcore.clock_comparator); |
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} |
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static void stp_timing_alert(struct stp_irq_parm *); |
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|
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static void timing_alert_interrupt(struct ext_code ext_code, |
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unsigned int param32, unsigned long param64) |
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{ |
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inc_irq_stat(IRQEXT_TLA); |
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if (param32 & 0x00038000) |
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stp_timing_alert((struct stp_irq_parm *) ¶m32); |
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} |
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|
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static void stp_reset(void); |
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void read_persistent_clock64(struct timespec64 *ts) |
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{ |
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union tod_clock clk; |
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u64 delta; |
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delta = initial_leap_seconds + TOD_UNIX_EPOCH; |
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store_tod_clock_ext(&clk); |
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clk.eitod -= delta; |
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ext_to_timespec64(&clk, ts); |
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} |
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|
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void __init read_persistent_wall_and_boot_offset(struct timespec64 *wall_time, |
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struct timespec64 *boot_offset) |
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{ |
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struct timespec64 boot_time; |
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union tod_clock clk; |
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u64 delta; |
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delta = initial_leap_seconds + TOD_UNIX_EPOCH; |
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clk = tod_clock_base; |
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clk.eitod -= delta; |
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ext_to_timespec64(&clk, &boot_time); |
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read_persistent_clock64(wall_time); |
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*boot_offset = timespec64_sub(*wall_time, boot_time); |
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} |
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static u64 read_tod_clock(struct clocksource *cs) |
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{ |
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unsigned long now, adj; |
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preempt_disable(); /* protect from changes to steering parameters */ |
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now = get_tod_clock(); |
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adj = tod_steering_end - now; |
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if (unlikely((s64) adj > 0)) |
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/* |
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* manually steer by 1 cycle every 2^16 cycles. This |
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* corresponds to shifting the tod delta by 15. 1s is |
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* therefore steered in ~9h. The adjust will decrease |
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* over time, until it finally reaches 0. |
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*/ |
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now += (tod_steering_delta < 0) ? (adj >> 15) : -(adj >> 15); |
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preempt_enable(); |
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return now; |
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} |
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static struct clocksource clocksource_tod = { |
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.name = "tod", |
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.rating = 400, |
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.read = read_tod_clock, |
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.mask = CLOCKSOURCE_MASK(64), |
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.mult = 1000, |
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.shift = 12, |
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.flags = CLOCK_SOURCE_IS_CONTINUOUS, |
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.vdso_clock_mode = VDSO_CLOCKMODE_TOD, |
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}; |
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struct clocksource * __init clocksource_default_clock(void) |
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{ |
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return &clocksource_tod; |
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} |
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/* |
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* Initialize the TOD clock and the CPU timer of |
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* the boot cpu. |
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*/ |
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void __init time_init(void) |
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{ |
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/* Reset time synchronization interfaces. */ |
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stp_reset(); |
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|
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/* request the clock comparator external interrupt */ |
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if (register_external_irq(EXT_IRQ_CLK_COMP, clock_comparator_interrupt)) |
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panic("Couldn't request external interrupt 0x1004"); |
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|
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/* request the timing alert external interrupt */ |
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if (register_external_irq(EXT_IRQ_TIMING_ALERT, timing_alert_interrupt)) |
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panic("Couldn't request external interrupt 0x1406"); |
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if (__clocksource_register(&clocksource_tod) != 0) |
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panic("Could not register TOD clock source"); |
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/* Enable TOD clock interrupts on the boot cpu. */ |
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init_cpu_timer(); |
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|
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/* Enable cpu timer interrupts on the boot cpu. */ |
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vtime_init(); |
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} |
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static DEFINE_PER_CPU(atomic_t, clock_sync_word); |
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static DEFINE_MUTEX(stp_mutex); |
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static unsigned long clock_sync_flags; |
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#define CLOCK_SYNC_HAS_STP 0 |
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#define CLOCK_SYNC_STP 1 |
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#define CLOCK_SYNC_STPINFO_VALID 2 |
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|
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/* |
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* The get_clock function for the physical clock. It will get the current |
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* TOD clock, subtract the LPAR offset and write the result to *clock. |
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* The function returns 0 if the clock is in sync with the external time |
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* source. If the clock mode is local it will return -EOPNOTSUPP and |
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* -EAGAIN if the clock is not in sync with the external reference. |
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*/ |
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int get_phys_clock(unsigned long *clock) |
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{ |
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atomic_t *sw_ptr; |
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unsigned int sw0, sw1; |
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sw_ptr = &get_cpu_var(clock_sync_word); |
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sw0 = atomic_read(sw_ptr); |
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*clock = get_tod_clock() - lpar_offset; |
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sw1 = atomic_read(sw_ptr); |
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put_cpu_var(clock_sync_word); |
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if (sw0 == sw1 && (sw0 & 0x80000000U)) |
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/* Success: time is in sync. */ |
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return 0; |
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if (!test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags)) |
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return -EOPNOTSUPP; |
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if (!test_bit(CLOCK_SYNC_STP, &clock_sync_flags)) |
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return -EACCES; |
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return -EAGAIN; |
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} |
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EXPORT_SYMBOL(get_phys_clock); |
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|
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/* |
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* Make get_phys_clock() return -EAGAIN. |
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*/ |
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static void disable_sync_clock(void *dummy) |
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{ |
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atomic_t *sw_ptr = this_cpu_ptr(&clock_sync_word); |
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/* |
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* Clear the in-sync bit 2^31. All get_phys_clock calls will |
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* fail until the sync bit is turned back on. In addition |
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* increase the "sequence" counter to avoid the race of an |
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* stp event and the complete recovery against get_phys_clock. |
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*/ |
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atomic_andnot(0x80000000, sw_ptr); |
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atomic_inc(sw_ptr); |
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} |
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/* |
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* Make get_phys_clock() return 0 again. |
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* Needs to be called from a context disabled for preemption. |
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*/ |
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static void enable_sync_clock(void) |
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{ |
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atomic_t *sw_ptr = this_cpu_ptr(&clock_sync_word); |
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atomic_or(0x80000000, sw_ptr); |
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} |
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/* |
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* Function to check if the clock is in sync. |
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*/ |
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static inline int check_sync_clock(void) |
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{ |
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atomic_t *sw_ptr; |
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int rc; |
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sw_ptr = &get_cpu_var(clock_sync_word); |
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rc = (atomic_read(sw_ptr) & 0x80000000U) != 0; |
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put_cpu_var(clock_sync_word); |
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return rc; |
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} |
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/* |
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* Apply clock delta to the global data structures. |
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* This is called once on the CPU that performed the clock sync. |
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*/ |
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static void clock_sync_global(unsigned long delta) |
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{ |
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unsigned long now, adj; |
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struct ptff_qto qto; |
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int cs; |
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|
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/* Fixup the monotonic sched clock. */ |
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tod_clock_base.eitod += delta; |
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/* Adjust TOD steering parameters. */ |
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now = get_tod_clock(); |
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adj = tod_steering_end - now; |
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if (unlikely((s64) adj >= 0)) |
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/* Calculate how much of the old adjustment is left. */ |
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tod_steering_delta = (tod_steering_delta < 0) ? |
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-(adj >> 15) : (adj >> 15); |
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tod_steering_delta += delta; |
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if ((abs(tod_steering_delta) >> 48) != 0) |
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panic("TOD clock sync offset %li is too large to drift\n", |
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tod_steering_delta); |
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tod_steering_end = now + (abs(tod_steering_delta) << 15); |
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for (cs = 0; cs < CS_BASES; cs++) { |
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vdso_data[cs].arch_data.tod_steering_end = tod_steering_end; |
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vdso_data[cs].arch_data.tod_steering_delta = tod_steering_delta; |
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} |
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|
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/* Update LPAR offset. */ |
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if (ptff_query(PTFF_QTO) && ptff(&qto, sizeof(qto), PTFF_QTO) == 0) |
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lpar_offset = qto.tod_epoch_difference; |
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/* Call the TOD clock change notifier. */ |
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atomic_notifier_call_chain(&s390_epoch_delta_notifier, 0, &delta); |
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} |
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|
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/* |
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* Apply clock delta to the per-CPU data structures of this CPU. |
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* This is called for each online CPU after the call to clock_sync_global. |
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*/ |
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static void clock_sync_local(unsigned long delta) |
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{ |
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/* Add the delta to the clock comparator. */ |
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if (S390_lowcore.clock_comparator != clock_comparator_max) { |
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S390_lowcore.clock_comparator += delta; |
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set_clock_comparator(S390_lowcore.clock_comparator); |
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} |
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/* Adjust the last_update_clock time-stamp. */ |
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S390_lowcore.last_update_clock += delta; |
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} |
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|
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/* Single threaded workqueue used for stp sync events */ |
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static struct workqueue_struct *time_sync_wq; |
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|
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static void __init time_init_wq(void) |
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{ |
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if (time_sync_wq) |
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return; |
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time_sync_wq = create_singlethread_workqueue("timesync"); |
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} |
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|
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struct clock_sync_data { |
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atomic_t cpus; |
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int in_sync; |
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unsigned long clock_delta; |
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}; |
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|
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/* |
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* Server Time Protocol (STP) code. |
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*/ |
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static bool stp_online; |
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static struct stp_sstpi stp_info; |
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static void *stp_page; |
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static void stp_work_fn(struct work_struct *work); |
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static DECLARE_WORK(stp_work, stp_work_fn); |
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static struct timer_list stp_timer; |
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|
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static int __init early_parse_stp(char *p) |
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{ |
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return kstrtobool(p, &stp_online); |
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} |
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early_param("stp", early_parse_stp); |
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|
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/* |
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* Reset STP attachment. |
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*/ |
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static void __init stp_reset(void) |
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{ |
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int rc; |
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|
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stp_page = (void *) get_zeroed_page(GFP_ATOMIC); |
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rc = chsc_sstpc(stp_page, STP_OP_CTRL, 0x0000, NULL); |
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if (rc == 0) |
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set_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags); |
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else if (stp_online) { |
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pr_warn("The real or virtual hardware system does not provide an STP interface\n"); |
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free_page((unsigned long) stp_page); |
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stp_page = NULL; |
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stp_online = false; |
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} |
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} |
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|
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static void stp_timeout(struct timer_list *unused) |
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{ |
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queue_work(time_sync_wq, &stp_work); |
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} |
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|
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static int __init stp_init(void) |
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{ |
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if (!test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags)) |
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return 0; |
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timer_setup(&stp_timer, stp_timeout, 0); |
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time_init_wq(); |
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if (!stp_online) |
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return 0; |
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queue_work(time_sync_wq, &stp_work); |
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return 0; |
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} |
|
|
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arch_initcall(stp_init); |
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|
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/* |
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* STP timing alert. There are three causes: |
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* 1) timing status change |
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* 2) link availability change |
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* 3) time control parameter change |
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* In all three cases we are only interested in the clock source state. |
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* If a STP clock source is now available use it. |
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*/ |
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static void stp_timing_alert(struct stp_irq_parm *intparm) |
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{ |
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if (intparm->tsc || intparm->lac || intparm->tcpc) |
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queue_work(time_sync_wq, &stp_work); |
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} |
|
|
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/* |
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* STP sync check machine check. This is called when the timing state |
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* changes from the synchronized state to the unsynchronized state. |
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* After a STP sync check the clock is not in sync. The machine check |
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* is broadcasted to all cpus at the same time. |
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*/ |
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int stp_sync_check(void) |
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{ |
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disable_sync_clock(NULL); |
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return 1; |
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} |
|
|
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/* |
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* STP island condition machine check. This is called when an attached |
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* server attempts to communicate over an STP link and the servers |
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* have matching CTN ids and have a valid stratum-1 configuration |
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* but the configurations do not match. |
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*/ |
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int stp_island_check(void) |
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{ |
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disable_sync_clock(NULL); |
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return 1; |
|
} |
|
|
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void stp_queue_work(void) |
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{ |
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queue_work(time_sync_wq, &stp_work); |
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} |
|
|
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static int __store_stpinfo(void) |
|
{ |
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int rc = chsc_sstpi(stp_page, &stp_info, sizeof(struct stp_sstpi)); |
|
|
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if (rc) |
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clear_bit(CLOCK_SYNC_STPINFO_VALID, &clock_sync_flags); |
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else |
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set_bit(CLOCK_SYNC_STPINFO_VALID, &clock_sync_flags); |
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return rc; |
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} |
|
|
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static int stpinfo_valid(void) |
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{ |
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return stp_online && test_bit(CLOCK_SYNC_STPINFO_VALID, &clock_sync_flags); |
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} |
|
|
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static int stp_sync_clock(void *data) |
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{ |
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struct clock_sync_data *sync = data; |
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u64 clock_delta, flags; |
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static int first; |
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int rc; |
|
|
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enable_sync_clock(); |
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if (xchg(&first, 1) == 0) { |
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/* Wait until all other cpus entered the sync function. */ |
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while (atomic_read(&sync->cpus) != 0) |
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cpu_relax(); |
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rc = 0; |
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if (stp_info.todoff[0] || stp_info.todoff[1] || |
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stp_info.todoff[2] || stp_info.todoff[3] || |
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stp_info.tmd != 2) { |
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flags = vdso_update_begin(); |
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rc = chsc_sstpc(stp_page, STP_OP_SYNC, 0, |
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&clock_delta); |
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if (rc == 0) { |
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sync->clock_delta = clock_delta; |
|
clock_sync_global(clock_delta); |
|
rc = __store_stpinfo(); |
|
if (rc == 0 && stp_info.tmd != 2) |
|
rc = -EAGAIN; |
|
} |
|
vdso_update_end(flags); |
|
} |
|
sync->in_sync = rc ? -EAGAIN : 1; |
|
xchg(&first, 0); |
|
} else { |
|
/* Slave */ |
|
atomic_dec(&sync->cpus); |
|
/* Wait for in_sync to be set. */ |
|
while (READ_ONCE(sync->in_sync) == 0) |
|
__udelay(1); |
|
} |
|
if (sync->in_sync != 1) |
|
/* Didn't work. Clear per-cpu in sync bit again. */ |
|
disable_sync_clock(NULL); |
|
/* Apply clock delta to per-CPU fields of this CPU. */ |
|
clock_sync_local(sync->clock_delta); |
|
|
|
return 0; |
|
} |
|
|
|
static int stp_clear_leap(void) |
|
{ |
|
struct __kernel_timex txc; |
|
int ret; |
|
|
|
memset(&txc, 0, sizeof(txc)); |
|
|
|
ret = do_adjtimex(&txc); |
|
if (ret < 0) |
|
return ret; |
|
|
|
txc.modes = ADJ_STATUS; |
|
txc.status &= ~(STA_INS|STA_DEL); |
|
return do_adjtimex(&txc); |
|
} |
|
|
|
static void stp_check_leap(void) |
|
{ |
|
struct stp_stzi stzi; |
|
struct stp_lsoib *lsoib = &stzi.lsoib; |
|
struct __kernel_timex txc; |
|
int64_t timediff; |
|
int leapdiff, ret; |
|
|
|
if (!stp_info.lu || !check_sync_clock()) { |
|
/* |
|
* Either a scheduled leap second was removed by the operator, |
|
* or STP is out of sync. In both cases, clear the leap second |
|
* kernel flags. |
|
*/ |
|
if (stp_clear_leap() < 0) |
|
pr_err("failed to clear leap second flags\n"); |
|
return; |
|
} |
|
|
|
if (chsc_stzi(stp_page, &stzi, sizeof(stzi))) { |
|
pr_err("stzi failed\n"); |
|
return; |
|
} |
|
|
|
timediff = tod_to_ns(lsoib->nlsout - get_tod_clock()) / NSEC_PER_SEC; |
|
leapdiff = lsoib->nlso - lsoib->also; |
|
|
|
if (leapdiff != 1 && leapdiff != -1) { |
|
pr_err("Cannot schedule %d leap seconds\n", leapdiff); |
|
return; |
|
} |
|
|
|
if (timediff < 0) { |
|
if (stp_clear_leap() < 0) |
|
pr_err("failed to clear leap second flags\n"); |
|
} else if (timediff < 7200) { |
|
memset(&txc, 0, sizeof(txc)); |
|
ret = do_adjtimex(&txc); |
|
if (ret < 0) |
|
return; |
|
|
|
txc.modes = ADJ_STATUS; |
|
if (leapdiff > 0) |
|
txc.status |= STA_INS; |
|
else |
|
txc.status |= STA_DEL; |
|
ret = do_adjtimex(&txc); |
|
if (ret < 0) |
|
pr_err("failed to set leap second flags\n"); |
|
/* arm Timer to clear leap second flags */ |
|
mod_timer(&stp_timer, jiffies + msecs_to_jiffies(14400 * MSEC_PER_SEC)); |
|
} else { |
|
/* The day the leap second is scheduled for hasn't been reached. Retry |
|
* in one hour. |
|
*/ |
|
mod_timer(&stp_timer, jiffies + msecs_to_jiffies(3600 * MSEC_PER_SEC)); |
|
} |
|
} |
|
|
|
/* |
|
* STP work. Check for the STP state and take over the clock |
|
* synchronization if the STP clock source is usable. |
|
*/ |
|
static void stp_work_fn(struct work_struct *work) |
|
{ |
|
struct clock_sync_data stp_sync; |
|
int rc; |
|
|
|
/* prevent multiple execution. */ |
|
mutex_lock(&stp_mutex); |
|
|
|
if (!stp_online) { |
|
chsc_sstpc(stp_page, STP_OP_CTRL, 0x0000, NULL); |
|
del_timer_sync(&stp_timer); |
|
goto out_unlock; |
|
} |
|
|
|
rc = chsc_sstpc(stp_page, STP_OP_CTRL, 0xf0e0, NULL); |
|
if (rc) |
|
goto out_unlock; |
|
|
|
rc = __store_stpinfo(); |
|
if (rc || stp_info.c == 0) |
|
goto out_unlock; |
|
|
|
/* Skip synchronization if the clock is already in sync. */ |
|
if (!check_sync_clock()) { |
|
memset(&stp_sync, 0, sizeof(stp_sync)); |
|
cpus_read_lock(); |
|
atomic_set(&stp_sync.cpus, num_online_cpus() - 1); |
|
stop_machine_cpuslocked(stp_sync_clock, &stp_sync, cpu_online_mask); |
|
cpus_read_unlock(); |
|
} |
|
|
|
if (!check_sync_clock()) |
|
/* |
|
* There is a usable clock but the synchonization failed. |
|
* Retry after a second. |
|
*/ |
|
mod_timer(&stp_timer, jiffies + msecs_to_jiffies(MSEC_PER_SEC)); |
|
else if (stp_info.lu) |
|
stp_check_leap(); |
|
|
|
out_unlock: |
|
mutex_unlock(&stp_mutex); |
|
} |
|
|
|
/* |
|
* STP subsys sysfs interface functions |
|
*/ |
|
static struct bus_type stp_subsys = { |
|
.name = "stp", |
|
.dev_name = "stp", |
|
}; |
|
|
|
static ssize_t ctn_id_show(struct device *dev, |
|
struct device_attribute *attr, |
|
char *buf) |
|
{ |
|
ssize_t ret = -ENODATA; |
|
|
|
mutex_lock(&stp_mutex); |
|
if (stpinfo_valid()) |
|
ret = sprintf(buf, "%016lx\n", |
|
*(unsigned long *) stp_info.ctnid); |
|
mutex_unlock(&stp_mutex); |
|
return ret; |
|
} |
|
|
|
static DEVICE_ATTR_RO(ctn_id); |
|
|
|
static ssize_t ctn_type_show(struct device *dev, |
|
struct device_attribute *attr, |
|
char *buf) |
|
{ |
|
ssize_t ret = -ENODATA; |
|
|
|
mutex_lock(&stp_mutex); |
|
if (stpinfo_valid()) |
|
ret = sprintf(buf, "%i\n", stp_info.ctn); |
|
mutex_unlock(&stp_mutex); |
|
return ret; |
|
} |
|
|
|
static DEVICE_ATTR_RO(ctn_type); |
|
|
|
static ssize_t dst_offset_show(struct device *dev, |
|
struct device_attribute *attr, |
|
char *buf) |
|
{ |
|
ssize_t ret = -ENODATA; |
|
|
|
mutex_lock(&stp_mutex); |
|
if (stpinfo_valid() && (stp_info.vbits & 0x2000)) |
|
ret = sprintf(buf, "%i\n", (int)(s16) stp_info.dsto); |
|
mutex_unlock(&stp_mutex); |
|
return ret; |
|
} |
|
|
|
static DEVICE_ATTR_RO(dst_offset); |
|
|
|
static ssize_t leap_seconds_show(struct device *dev, |
|
struct device_attribute *attr, |
|
char *buf) |
|
{ |
|
ssize_t ret = -ENODATA; |
|
|
|
mutex_lock(&stp_mutex); |
|
if (stpinfo_valid() && (stp_info.vbits & 0x8000)) |
|
ret = sprintf(buf, "%i\n", (int)(s16) stp_info.leaps); |
|
mutex_unlock(&stp_mutex); |
|
return ret; |
|
} |
|
|
|
static DEVICE_ATTR_RO(leap_seconds); |
|
|
|
static ssize_t leap_seconds_scheduled_show(struct device *dev, |
|
struct device_attribute *attr, |
|
char *buf) |
|
{ |
|
struct stp_stzi stzi; |
|
ssize_t ret; |
|
|
|
mutex_lock(&stp_mutex); |
|
if (!stpinfo_valid() || !(stp_info.vbits & 0x8000) || !stp_info.lu) { |
|
mutex_unlock(&stp_mutex); |
|
return -ENODATA; |
|
} |
|
|
|
ret = chsc_stzi(stp_page, &stzi, sizeof(stzi)); |
|
mutex_unlock(&stp_mutex); |
|
if (ret < 0) |
|
return ret; |
|
|
|
if (!stzi.lsoib.p) |
|
return sprintf(buf, "0,0\n"); |
|
|
|
return sprintf(buf, "%lu,%d\n", |
|
tod_to_ns(stzi.lsoib.nlsout - TOD_UNIX_EPOCH) / NSEC_PER_SEC, |
|
stzi.lsoib.nlso - stzi.lsoib.also); |
|
} |
|
|
|
static DEVICE_ATTR_RO(leap_seconds_scheduled); |
|
|
|
static ssize_t stratum_show(struct device *dev, |
|
struct device_attribute *attr, |
|
char *buf) |
|
{ |
|
ssize_t ret = -ENODATA; |
|
|
|
mutex_lock(&stp_mutex); |
|
if (stpinfo_valid()) |
|
ret = sprintf(buf, "%i\n", (int)(s16) stp_info.stratum); |
|
mutex_unlock(&stp_mutex); |
|
return ret; |
|
} |
|
|
|
static DEVICE_ATTR_RO(stratum); |
|
|
|
static ssize_t time_offset_show(struct device *dev, |
|
struct device_attribute *attr, |
|
char *buf) |
|
{ |
|
ssize_t ret = -ENODATA; |
|
|
|
mutex_lock(&stp_mutex); |
|
if (stpinfo_valid() && (stp_info.vbits & 0x0800)) |
|
ret = sprintf(buf, "%i\n", (int) stp_info.tto); |
|
mutex_unlock(&stp_mutex); |
|
return ret; |
|
} |
|
|
|
static DEVICE_ATTR_RO(time_offset); |
|
|
|
static ssize_t time_zone_offset_show(struct device *dev, |
|
struct device_attribute *attr, |
|
char *buf) |
|
{ |
|
ssize_t ret = -ENODATA; |
|
|
|
mutex_lock(&stp_mutex); |
|
if (stpinfo_valid() && (stp_info.vbits & 0x4000)) |
|
ret = sprintf(buf, "%i\n", (int)(s16) stp_info.tzo); |
|
mutex_unlock(&stp_mutex); |
|
return ret; |
|
} |
|
|
|
static DEVICE_ATTR_RO(time_zone_offset); |
|
|
|
static ssize_t timing_mode_show(struct device *dev, |
|
struct device_attribute *attr, |
|
char *buf) |
|
{ |
|
ssize_t ret = -ENODATA; |
|
|
|
mutex_lock(&stp_mutex); |
|
if (stpinfo_valid()) |
|
ret = sprintf(buf, "%i\n", stp_info.tmd); |
|
mutex_unlock(&stp_mutex); |
|
return ret; |
|
} |
|
|
|
static DEVICE_ATTR_RO(timing_mode); |
|
|
|
static ssize_t timing_state_show(struct device *dev, |
|
struct device_attribute *attr, |
|
char *buf) |
|
{ |
|
ssize_t ret = -ENODATA; |
|
|
|
mutex_lock(&stp_mutex); |
|
if (stpinfo_valid()) |
|
ret = sprintf(buf, "%i\n", stp_info.tst); |
|
mutex_unlock(&stp_mutex); |
|
return ret; |
|
} |
|
|
|
static DEVICE_ATTR_RO(timing_state); |
|
|
|
static ssize_t online_show(struct device *dev, |
|
struct device_attribute *attr, |
|
char *buf) |
|
{ |
|
return sprintf(buf, "%i\n", stp_online); |
|
} |
|
|
|
static ssize_t online_store(struct device *dev, |
|
struct device_attribute *attr, |
|
const char *buf, size_t count) |
|
{ |
|
unsigned int value; |
|
|
|
value = simple_strtoul(buf, NULL, 0); |
|
if (value != 0 && value != 1) |
|
return -EINVAL; |
|
if (!test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags)) |
|
return -EOPNOTSUPP; |
|
mutex_lock(&stp_mutex); |
|
stp_online = value; |
|
if (stp_online) |
|
set_bit(CLOCK_SYNC_STP, &clock_sync_flags); |
|
else |
|
clear_bit(CLOCK_SYNC_STP, &clock_sync_flags); |
|
queue_work(time_sync_wq, &stp_work); |
|
mutex_unlock(&stp_mutex); |
|
return count; |
|
} |
|
|
|
/* |
|
* Can't use DEVICE_ATTR because the attribute should be named |
|
* stp/online but dev_attr_online already exists in this file .. |
|
*/ |
|
static DEVICE_ATTR_RW(online); |
|
|
|
static struct attribute *stp_dev_attrs[] = { |
|
&dev_attr_ctn_id.attr, |
|
&dev_attr_ctn_type.attr, |
|
&dev_attr_dst_offset.attr, |
|
&dev_attr_leap_seconds.attr, |
|
&dev_attr_online.attr, |
|
&dev_attr_leap_seconds_scheduled.attr, |
|
&dev_attr_stratum.attr, |
|
&dev_attr_time_offset.attr, |
|
&dev_attr_time_zone_offset.attr, |
|
&dev_attr_timing_mode.attr, |
|
&dev_attr_timing_state.attr, |
|
NULL |
|
}; |
|
ATTRIBUTE_GROUPS(stp_dev); |
|
|
|
static int __init stp_init_sysfs(void) |
|
{ |
|
return subsys_system_register(&stp_subsys, stp_dev_groups); |
|
} |
|
|
|
device_initcall(stp_init_sysfs);
|
|
|