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![Sven Schnelle](/assets/img/avatar_default.png)
clock_delta is declared as unsigned long in various places. However, the clock sync delta can be negative. This would add a huge positive offset in clock_sync_global where clock_delta is added to clk.eitod which is a 72 bit integer. Declare it as signed long to fix this. Cc: stable@vger.kernel.org Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
939 lines
23 KiB
C
939 lines
23 KiB
C
// 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 (hp@de.ibm.com),
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* Martin Schwidefsky (schwidefsky@de.ibm.com),
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* Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com)
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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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#define KMSG_COMPONENT "time"
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#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
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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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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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static DEFINE_PER_CPU(struct clock_event_device, comparators);
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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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unsigned char ptff_function_mask[16];
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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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* 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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/* 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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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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/* 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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/* 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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* 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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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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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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void clock_comparator_work(void)
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{
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struct clock_event_device *cd;
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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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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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* 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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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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/* Enable clock comparator timer interrupt. */
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__ctl_set_bit(0,11);
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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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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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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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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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/* 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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/* 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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/* 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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* 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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* 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(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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/* 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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/* 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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* 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(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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/* Single threaded workqueue used for stp sync events */
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static struct workqueue_struct *time_sync_wq;
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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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struct clock_sync_data {
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atomic_t cpus;
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int in_sync;
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long clock_delta;
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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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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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* 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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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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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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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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* 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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*/
|
|
static void stp_timing_alert(struct stp_irq_parm *intparm)
|
|
{
|
|
if (intparm->tsc || intparm->lac || intparm->tcpc)
|
|
queue_work(time_sync_wq, &stp_work);
|
|
}
|
|
|
|
/*
|
|
* STP sync check machine check. This is called when the timing state
|
|
* changes from the synchronized state to the unsynchronized state.
|
|
* After a STP sync check the clock is not in sync. The machine check
|
|
* is broadcasted to all cpus at the same time.
|
|
*/
|
|
int stp_sync_check(void)
|
|
{
|
|
disable_sync_clock(NULL);
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* STP island condition machine check. This is called when an attached
|
|
* server attempts to communicate over an STP link and the servers
|
|
* have matching CTN ids and have a valid stratum-1 configuration
|
|
* but the configurations do not match.
|
|
*/
|
|
int stp_island_check(void)
|
|
{
|
|
disable_sync_clock(NULL);
|
|
return 1;
|
|
}
|
|
|
|
void stp_queue_work(void)
|
|
{
|
|
queue_work(time_sync_wq, &stp_work);
|
|
}
|
|
|
|
static int __store_stpinfo(void)
|
|
{
|
|
int rc = chsc_sstpi(stp_page, &stp_info, sizeof(struct stp_sstpi));
|
|
|
|
if (rc)
|
|
clear_bit(CLOCK_SYNC_STPINFO_VALID, &clock_sync_flags);
|
|
else
|
|
set_bit(CLOCK_SYNC_STPINFO_VALID, &clock_sync_flags);
|
|
return rc;
|
|
}
|
|
|
|
static int stpinfo_valid(void)
|
|
{
|
|
return stp_online && test_bit(CLOCK_SYNC_STPINFO_VALID, &clock_sync_flags);
|
|
}
|
|
|
|
static int stp_sync_clock(void *data)
|
|
{
|
|
struct clock_sync_data *sync = data;
|
|
long clock_delta, flags;
|
|
static int first;
|
|
int rc;
|
|
|
|
enable_sync_clock();
|
|
if (xchg(&first, 1) == 0) {
|
|
/* Wait until all other cpus entered the sync function. */
|
|
while (atomic_read(&sync->cpus) != 0)
|
|
cpu_relax();
|
|
rc = 0;
|
|
if (stp_info.todoff || stp_info.tmd != 2) {
|
|
flags = vdso_update_begin();
|
|
rc = chsc_sstpc(stp_page, STP_OP_SYNC, 0,
|
|
&clock_delta);
|
|
if (rc == 0) {
|
|
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);
|