+++ /dev/null
-/*
- * Copyright 2012 Tilera Corporation. All Rights Reserved.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation, version 2.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
- * NON INFRINGEMENT. See the GNU General Public License for
- * more details.
- */
-
-#define VDSO_BUILD /* avoid some shift warnings for -m32 in <asm/page.h> */
-#include <linux/time.h>
-#include <asm/timex.h>
-#include <asm/unistd.h>
-#include <asm/vdso.h>
-
-#if CHIP_HAS_SPLIT_CYCLE()
-static inline cycles_t get_cycles_inline(void)
-{
- unsigned int high = __insn_mfspr(SPR_CYCLE_HIGH);
- unsigned int low = __insn_mfspr(SPR_CYCLE_LOW);
- unsigned int high2 = __insn_mfspr(SPR_CYCLE_HIGH);
-
- while (unlikely(high != high2)) {
- low = __insn_mfspr(SPR_CYCLE_LOW);
- high = high2;
- high2 = __insn_mfspr(SPR_CYCLE_HIGH);
- }
-
- return (((cycles_t)high) << 32) | low;
-}
-#define get_cycles get_cycles_inline
-#endif
-
-struct syscall_return_value {
- long value;
- long error;
-};
-
-/*
- * Find out the vDSO data page address in the process address space.
- */
-inline unsigned long get_datapage(void)
-{
- unsigned long ret;
-
- /* vdso data page located in the 2nd vDSO page. */
- asm volatile ("lnk %0" : "=r"(ret));
- ret &= ~(PAGE_SIZE - 1);
- ret += PAGE_SIZE;
-
- return ret;
-}
-
-static inline u64 vgetsns(struct vdso_data *vdso)
-{
- return ((get_cycles() - vdso->cycle_last) & vdso->mask) * vdso->mult;
-}
-
-static inline int do_realtime(struct vdso_data *vdso, struct timespec *ts)
-{
- unsigned count;
- u64 ns;
-
- do {
- count = raw_read_seqcount_begin(&vdso->tb_seq);
- ts->tv_sec = vdso->wall_time_sec;
- ns = vdso->wall_time_snsec;
- ns += vgetsns(vdso);
- ns >>= vdso->shift;
- } while (unlikely(read_seqcount_retry(&vdso->tb_seq, count)));
-
- ts->tv_sec += __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns);
- ts->tv_nsec = ns;
-
- return 0;
-}
-
-static inline int do_monotonic(struct vdso_data *vdso, struct timespec *ts)
-{
- unsigned count;
- u64 ns;
-
- do {
- count = raw_read_seqcount_begin(&vdso->tb_seq);
- ts->tv_sec = vdso->monotonic_time_sec;
- ns = vdso->monotonic_time_snsec;
- ns += vgetsns(vdso);
- ns >>= vdso->shift;
- } while (unlikely(read_seqcount_retry(&vdso->tb_seq, count)));
-
- ts->tv_sec += __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns);
- ts->tv_nsec = ns;
-
- return 0;
-}
-
-static inline int do_realtime_coarse(struct vdso_data *vdso,
- struct timespec *ts)
-{
- unsigned count;
-
- do {
- count = raw_read_seqcount_begin(&vdso->tb_seq);
- ts->tv_sec = vdso->wall_time_coarse_sec;
- ts->tv_nsec = vdso->wall_time_coarse_nsec;
- } while (unlikely(read_seqcount_retry(&vdso->tb_seq, count)));
-
- return 0;
-}
-
-static inline int do_monotonic_coarse(struct vdso_data *vdso,
- struct timespec *ts)
-{
- unsigned count;
-
- do {
- count = raw_read_seqcount_begin(&vdso->tb_seq);
- ts->tv_sec = vdso->monotonic_time_coarse_sec;
- ts->tv_nsec = vdso->monotonic_time_coarse_nsec;
- } while (unlikely(read_seqcount_retry(&vdso->tb_seq, count)));
-
- return 0;
-}
-
-struct syscall_return_value __vdso_gettimeofday(struct timeval *tv,
- struct timezone *tz)
-{
- struct syscall_return_value ret = { 0, 0 };
- unsigned count;
- struct vdso_data *vdso = (struct vdso_data *)get_datapage();
-
- /* The use of the timezone is obsolete, normally tz is NULL. */
- if (unlikely(tz != NULL)) {
- do {
- count = raw_read_seqcount_begin(&vdso->tz_seq);
- tz->tz_minuteswest = vdso->tz_minuteswest;
- tz->tz_dsttime = vdso->tz_dsttime;
- } while (unlikely(read_seqcount_retry(&vdso->tz_seq, count)));
- }
-
- if (unlikely(tv == NULL))
- return ret;
-
- do_realtime(vdso, (struct timespec *)tv);
- tv->tv_usec /= 1000;
-
- return ret;
-}
-
-int gettimeofday(struct timeval *tv, struct timezone *tz)
- __attribute__((weak, alias("__vdso_gettimeofday")));
-
-static struct syscall_return_value vdso_fallback_gettime(long clock,
- struct timespec *ts)
-{
- struct syscall_return_value ret;
- __asm__ __volatile__ (
- "swint1"
- : "=R00" (ret.value), "=R01" (ret.error)
- : "R10" (__NR_clock_gettime), "R00" (clock), "R01" (ts)
- : "r2", "r3", "r4", "r5", "r6", "r7",
- "r8", "r9", "r11", "r12", "r13", "r14", "r15",
- "r16", "r17", "r18", "r19", "r20", "r21", "r22", "r23",
- "r24", "r25", "r26", "r27", "r28", "r29", "memory");
- return ret;
-}
-
-struct syscall_return_value __vdso_clock_gettime(clockid_t clock,
- struct timespec *ts)
-{
- struct vdso_data *vdso = (struct vdso_data *)get_datapage();
- struct syscall_return_value ret = { 0, 0 };
-
- switch (clock) {
- case CLOCK_REALTIME:
- do_realtime(vdso, ts);
- return ret;
- case CLOCK_MONOTONIC:
- do_monotonic(vdso, ts);
- return ret;
- case CLOCK_REALTIME_COARSE:
- do_realtime_coarse(vdso, ts);
- return ret;
- case CLOCK_MONOTONIC_COARSE:
- do_monotonic_coarse(vdso, ts);
- return ret;
- default:
- return vdso_fallback_gettime(clock, ts);
- }
-}
-
-int clock_gettime(clockid_t clock, struct timespec *ts)
- __attribute__((weak, alias("__vdso_clock_gettime")));
git.samba.org / sfrench / cifs-2.6.git / blobdiff