// SPDX-License-Identifier: GPL-2.0-only
/*
+ * ARM userspace implementations of gettimeofday() and similar.
+ *
* Copyright 2015 Mentor Graphics Corporation.
*/
-
-#include <linux/compiler.h>
-#include <linux/hrtimer.h>
#include <linux/time.h>
-#include <asm/barrier.h>
-#include <asm/bug.h>
-#include <asm/cp15.h>
-#include <asm/page.h>
-#include <asm/unistd.h>
-#include <asm/vdso_datapage.h>
-
-#ifndef CONFIG_AEABI
-#error This code depends on AEABI system call conventions
-#endif
-
-extern struct vdso_data *__get_datapage(void);
-
-static notrace u32 __vdso_read_begin(const struct vdso_data *vdata)
-{
- u32 seq;
-repeat:
- seq = READ_ONCE(vdata->seq_count);
- if (seq & 1) {
- cpu_relax();
- goto repeat;
- }
- return seq;
-}
-
-static notrace u32 vdso_read_begin(const struct vdso_data *vdata)
-{
- u32 seq;
-
- seq = __vdso_read_begin(vdata);
-
- smp_rmb(); /* Pairs with smp_wmb in vdso_write_end */
- return seq;
-}
-
-static notrace int vdso_read_retry(const struct vdso_data *vdata, u32 start)
-{
- smp_rmb(); /* Pairs with smp_wmb in vdso_write_begin */
- return vdata->seq_count != start;
-}
-
-static notrace long clock_gettime_fallback(clockid_t _clkid,
- struct timespec *_ts)
-{
- register struct timespec *ts asm("r1") = _ts;
- register clockid_t clkid asm("r0") = _clkid;
- register long ret asm ("r0");
- register long nr asm("r7") = __NR_clock_gettime;
-
- asm volatile(
- " swi #0\n"
- : "=r" (ret)
- : "r" (clkid), "r" (ts), "r" (nr)
- : "memory");
-
- return ret;
-}
-
-static notrace int do_realtime_coarse(struct timespec *ts,
- struct vdso_data *vdata)
-{
- u32 seq;
+#include <linux/types.h>
- do {
- seq = vdso_read_begin(vdata);
-
- ts->tv_sec = vdata->xtime_coarse_sec;
- ts->tv_nsec = vdata->xtime_coarse_nsec;
-
- } while (vdso_read_retry(vdata, seq));
-
- return 0;
-}
-
-static notrace int do_monotonic_coarse(struct timespec *ts,
- struct vdso_data *vdata)
+int __vdso_clock_gettime(clockid_t clock,
+ struct old_timespec32 *ts)
{
- struct timespec tomono;
- u32 seq;
-
- do {
- seq = vdso_read_begin(vdata);
-
- ts->tv_sec = vdata->xtime_coarse_sec;
- ts->tv_nsec = vdata->xtime_coarse_nsec;
-
- tomono.tv_sec = vdata->wtm_clock_sec;
- tomono.tv_nsec = vdata->wtm_clock_nsec;
-
- } while (vdso_read_retry(vdata, seq));
-
- ts->tv_sec += tomono.tv_sec;
- timespec_add_ns(ts, tomono.tv_nsec);
-
- return 0;
+ return __cvdso_clock_gettime32(clock, ts);
}
-#ifdef CONFIG_ARM_ARCH_TIMER
-
-static notrace u64 get_ns(struct vdso_data *vdata)
-{
- u64 cycle_delta;
- u64 cycle_now;
- u64 nsec;
-
- isb();
- cycle_now = read_sysreg(CNTVCT);
-
- cycle_delta = (cycle_now - vdata->cs_cycle_last) & vdata->cs_mask;
-
- nsec = (cycle_delta * vdata->cs_mult) + vdata->xtime_clock_snsec;
- nsec >>= vdata->cs_shift;
-
- return nsec;
-}
-
-static notrace int do_realtime(struct timespec *ts, struct vdso_data *vdata)
+int __vdso_gettimeofday(struct __kernel_old_timeval *tv,
+ struct timezone *tz)
{
- u64 nsecs;
- u32 seq;
-
- do {
- seq = vdso_read_begin(vdata);
-
- if (!vdata->tk_is_cntvct)
- return -1;
-
- ts->tv_sec = vdata->xtime_clock_sec;
- nsecs = get_ns(vdata);
-
- } while (vdso_read_retry(vdata, seq));
-
- ts->tv_nsec = 0;
- timespec_add_ns(ts, nsecs);
-
- return 0;
-}
-
-static notrace int do_monotonic(struct timespec *ts, struct vdso_data *vdata)
-{
- struct timespec tomono;
- u64 nsecs;
- u32 seq;
-
- do {
- seq = vdso_read_begin(vdata);
-
- if (!vdata->tk_is_cntvct)
- return -1;
-
- ts->tv_sec = vdata->xtime_clock_sec;
- nsecs = get_ns(vdata);
-
- tomono.tv_sec = vdata->wtm_clock_sec;
- tomono.tv_nsec = vdata->wtm_clock_nsec;
-
- } while (vdso_read_retry(vdata, seq));
-
- ts->tv_sec += tomono.tv_sec;
- ts->tv_nsec = 0;
- timespec_add_ns(ts, nsecs + tomono.tv_nsec);
-
- return 0;
-}
-
-#else /* CONFIG_ARM_ARCH_TIMER */
-
-static notrace int do_realtime(struct timespec *ts, struct vdso_data *vdata)
-{
- return -1;
-}
-
-static notrace int do_monotonic(struct timespec *ts, struct vdso_data *vdata)
-{
- return -1;
-}
-
-#endif /* CONFIG_ARM_ARCH_TIMER */
-
-notrace int __vdso_clock_gettime(clockid_t clkid, struct timespec *ts)
-{
- struct vdso_data *vdata;
- int ret = -1;
-
- vdata = __get_datapage();
-
- switch (clkid) {
- case CLOCK_REALTIME_COARSE:
- ret = do_realtime_coarse(ts, vdata);
- break;
- case CLOCK_MONOTONIC_COARSE:
- ret = do_monotonic_coarse(ts, vdata);
- break;
- case CLOCK_REALTIME:
- ret = do_realtime(ts, vdata);
- break;
- case CLOCK_MONOTONIC:
- ret = do_monotonic(ts, vdata);
- break;
- default:
- break;
- }
-
- if (ret)
- ret = clock_gettime_fallback(clkid, ts);
-
- return ret;
-}
-
-static notrace long gettimeofday_fallback(struct timeval *_tv,
- struct timezone *_tz)
-{
- register struct timezone *tz asm("r1") = _tz;
- register struct timeval *tv asm("r0") = _tv;
- register long ret asm ("r0");
- register long nr asm("r7") = __NR_gettimeofday;
-
- asm volatile(
- " swi #0\n"
- : "=r" (ret)
- : "r" (tv), "r" (tz), "r" (nr)
- : "memory");
-
- return ret;
-}
-
-notrace int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz)
-{
- struct timespec ts;
- struct vdso_data *vdata;
- int ret;
-
- vdata = __get_datapage();
-
- ret = do_realtime(&ts, vdata);
- if (ret)
- return gettimeofday_fallback(tv, tz);
-
- if (tv) {
- tv->tv_sec = ts.tv_sec;
- tv->tv_usec = ts.tv_nsec / 1000;
- }
- if (tz) {
- tz->tz_minuteswest = vdata->tz_minuteswest;
- tz->tz_dsttime = vdata->tz_dsttime;
- }
-
- return ret;
+ return __cvdso_gettimeofday(tv, tz);
}
/* Avoid unresolved references emitted by GCC */
git.samba.org / sfrench / cifs-2.6.git / blobdiff