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Diffstat (limited to 'arch/arm64/include/asm/vdso/gettimeofday.h')
-rw-r--r--arch/arm64/include/asm/vdso/gettimeofday.h103
1 files changed, 103 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/vdso/gettimeofday.h b/arch/arm64/include/asm/vdso/gettimeofday.h
new file mode 100644
index 000000000000..b08f476b72b4
--- /dev/null
+++ b/arch/arm64/include/asm/vdso/gettimeofday.h
@@ -0,0 +1,103 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2018 ARM Limited
+ */
+#ifndef __ASM_VDSO_GETTIMEOFDAY_H
+#define __ASM_VDSO_GETTIMEOFDAY_H
+
+#ifndef __ASSEMBLY__
+
+#include <asm/unistd.h>
+#include <uapi/linux/time.h>
+
+#define __VDSO_USE_SYSCALL ULLONG_MAX
+
+#define VDSO_HAS_CLOCK_GETRES 1
+
+static __always_inline
+int gettimeofday_fallback(struct __kernel_old_timeval *_tv,
+ struct timezone *_tz)
+{
+ register struct timezone *tz asm("x1") = _tz;
+ register struct __kernel_old_timeval *tv asm("x0") = _tv;
+ register long ret asm ("x0");
+ register long nr asm("x8") = __NR_gettimeofday;
+
+ asm volatile(
+ " svc #0\n"
+ : "=r" (ret)
+ : "r" (tv), "r" (tz), "r" (nr)
+ : "memory");
+
+ return ret;
+}
+
+static __always_inline
+long clock_gettime_fallback(clockid_t _clkid, struct __kernel_timespec *_ts)
+{
+ register struct __kernel_timespec *ts asm("x1") = _ts;
+ register clockid_t clkid asm("x0") = _clkid;
+ register long ret asm ("x0");
+ register long nr asm("x8") = __NR_clock_gettime;
+
+ asm volatile(
+ " svc #0\n"
+ : "=r" (ret)
+ : "r" (clkid), "r" (ts), "r" (nr)
+ : "memory");
+
+ return ret;
+}
+
+static __always_inline
+int clock_getres_fallback(clockid_t _clkid, struct __kernel_timespec *_ts)
+{
+ register struct __kernel_timespec *ts asm("x1") = _ts;
+ register clockid_t clkid asm("x0") = _clkid;
+ register long ret asm ("x0");
+ register long nr asm("x8") = __NR_clock_getres;
+
+ asm volatile(
+ " svc #0\n"
+ : "=r" (ret)
+ : "r" (clkid), "r" (ts), "r" (nr)
+ : "memory");
+
+ return ret;
+}
+
+static __always_inline u64 __arch_get_hw_counter(s32 clock_mode)
+{
+ u64 res;
+
+ /*
+ * clock_mode == 0 implies that vDSO are enabled otherwise
+ * fallback on syscall.
+ */
+ if (clock_mode)
+ return __VDSO_USE_SYSCALL;
+
+ /*
+ * This isb() is required to prevent that the counter value
+ * is speculated.
+ */
+ isb();
+ asm volatile("mrs %0, cntvct_el0" : "=r" (res) :: "memory");
+ /*
+ * This isb() is required to prevent that the seq lock is
+ * speculated.#
+ */
+ isb();
+
+ return res;
+}
+
+static __always_inline
+const struct vdso_data *__arch_get_vdso_data(void)
+{
+ return _vdso_data;
+}
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* __ASM_VDSO_GETTIMEOFDAY_H */