diff options
Diffstat (limited to 'arch/arm/vdso/vgettimeofday.c')
-rw-r--r-- | arch/arm/vdso/vgettimeofday.c | 255 |
1 files changed, 15 insertions, 240 deletions
diff --git a/arch/arm/vdso/vgettimeofday.c b/arch/arm/vdso/vgettimeofday.c index d1fdbb12760a..1976c6f325a4 100644 --- a/arch/arm/vdso/vgettimeofday.c +++ b/arch/arm/vdso/vgettimeofday.c @@ -1,259 +1,34 @@ // 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; -} +#include <linux/types.h> -static notrace int vdso_read_retry(const struct vdso_data *vdata, u32 start) +int __vdso_clock_gettime(clockid_t clock, + struct old_timespec32 *ts) { - smp_rmb(); /* Pairs with smp_wmb in vdso_write_begin */ - return vdata->seq_count != start; + return __cvdso_clock_gettime32(clock, ts); } -static notrace long clock_gettime_fallback(clockid_t _clkid, - struct timespec *_ts) +int __vdso_clock_gettime64(clockid_t clock, + struct __kernel_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; + return __cvdso_clock_gettime(clock, ts); } -static notrace int do_realtime_coarse(struct timespec *ts, - struct vdso_data *vdata) +int __vdso_gettimeofday(struct __kernel_old_timeval *tv, + struct timezone *tz) { - u32 seq; - - 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; + return __cvdso_gettimeofday(tv, tz); } -static notrace int do_monotonic_coarse(struct timespec *ts, - struct vdso_data *vdata) +int __vdso_clock_getres(clockid_t clock_id, + struct old_timespec32 *res) { - 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; -} - -#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) -{ - 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_clock_getres_time32(clock_id, res); } /* Avoid unresolved references emitted by GCC */ |