diff --git a/arch/sparc/lib/Makefile b/arch/sparc/lib/Makefile
index 4a30bf1ca0e60fac92ec216d2f3fcd92028b1599..cc640bd791d5efd685684f27b9a6c974314dfb9c 100644
--- a/arch/sparc/lib/Makefile
+++ b/arch/sparc/lib/Makefile
@@ -4,3 +4,6 @@ CHECKFLAGS += -D__sparc__
lib-y += gptimer.o
lib-y += grtimer.o
lib-y += grtimer_longcount.o
+
+lib-$(CONFIG_ARCH_CUSTOM_BOOT_CODE) += clz_tab.o
+lib-$(CONFIG_ARCH_CUSTOM_BOOT_CODE) += divdi3.o
diff --git a/arch/sparc/lib/clz_tab.c b/arch/sparc/lib/clz_tab.c
new file mode 100644
index 0000000000000000000000000000000000000000..b6118d09f244b251956f8c53b49902cb12e97dec
--- /dev/null
+++ b/arch/sparc/lib/clz_tab.c
@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: GPL-2.0
+const unsigned char __clz_tab[] = {
+ 0, 1, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5,
+ 5, 5, 5, 5, 5, 5, 5, 5,
+ 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+ 6, 6, 6, 6, 6, 6, 6, 6,
+ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+ 7, 7, 7, 7, 7, 7, 7, 7,
+ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+ 7, 7, 7, 7, 7, 7, 7, 7,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 8, 8, 8, 8, 8, 8, 8, 8,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 8, 8, 8, 8, 8, 8, 8, 8,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 8, 8, 8, 8, 8, 8, 8, 8,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 8, 8, 8, 8, 8, 8, 8, 8,
+};
diff --git a/arch/sparc/lib/divdi3.S b/arch/sparc/lib/divdi3.S
new file mode 100644
index 0000000000000000000000000000000000000000..9614b48b6ef839fe52d8dcb463419634fe2d5770
--- /dev/null
+++ b/arch/sparc/lib/divdi3.S
@@ -0,0 +1,281 @@
+/* Copyright (C) 1989, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
+
+This file is part of GNU CC.
+
+GNU CC 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; either version 2, or (at your option)
+any later version.
+
+GNU CC 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. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU CC; see the file COPYING. If not, write to
+the Free Software Foundation, 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA. */
+
+ .text
+ .align 4
+ .globl __divdi3
+__divdi3:
+ save %sp,-104,%sp
+ cmp %i0,0
+ bge .LL40
+ mov 0,%l4
+ mov -1,%l4
+ sub %g0,%i1,%o0
+ mov %o0,%o5
+ subcc %g0,%o0,%g0
+ sub %g0,%i0,%o0
+ subx %o0,0,%o4
+ mov %o4,%i0
+ mov %o5,%i1
+.LL40:
+ cmp %i2,0
+ bge .LL84
+ mov %i3,%o4
+ xnor %g0,%l4,%l4
+ sub %g0,%i3,%o0
+ mov %o0,%o3
+ subcc %g0,%o0,%g0
+ sub %g0,%i2,%o0
+ subx %o0,0,%o2
+ mov %o2,%i2
+ mov %o3,%i3
+ mov %i3,%o4
+.LL84:
+ cmp %i2,0
+ bne .LL45
+ mov %i1,%i3
+ cmp %o4,%i0
+ bleu .LL46
+ mov %i3,%o1
+ mov 32,%g1
+ subcc %i0,%o4,%g0
+1: bcs 5f
+ addxcc %o1,%o1,%o1 ! shift n1n0 and a q-bit in lsb
+ sub %i0,%o4,%i0 ! this kills msb of n
+ addx %i0,%i0,%i0 ! so this cannot give carry
+ subcc %g1,1,%g1
+2: bne 1b
+ subcc %i0,%o4,%g0
+ bcs 3f
+ addxcc %o1,%o1,%o1 ! shift n1n0 and a q-bit in lsb
+ b 3f
+ sub %i0,%o4,%i0 ! this kills msb of n
+4: sub %i0,%o4,%i0
+5: addxcc %i0,%i0,%i0
+ bcc 2b
+ subcc %g1,1,%g1
+! Got carry from n. Subtract next step to cancel this carry.
+ bne 4b
+ addcc %o1,%o1,%o1 ! shift n1n0 and a 0-bit in lsb
+ sub %i0,%o4,%i0
+3: xnor %o1,0,%o1
+ b .LL50
+ mov 0,%o2
+.LL46:
+ cmp %o4,0
+ bne .LL85
+ mov %i0,%o2
+ mov 1,%o0
+ mov 0,%o1
+ wr %g0, 0, %y
+ udiv %o0, %o1, %o0
+ mov %o0,%o4
+ mov %i0,%o2
+.LL85:
+ mov 0,%g3
+ mov 32,%g1
+ subcc %g3,%o4,%g0
+1: bcs 5f
+ addxcc %o2,%o2,%o2 ! shift n1n0 and a q-bit in lsb
+ sub %g3,%o4,%g3 ! this kills msb of n
+ addx %g3,%g3,%g3 ! so this cannot give carry
+ subcc %g1,1,%g1
+2: bne 1b
+ subcc %g3,%o4,%g0
+ bcs 3f
+ addxcc %o2,%o2,%o2 ! shift n1n0 and a q-bit in lsb
+ b 3f
+ sub %g3,%o4,%g3 ! this kills msb of n
+4: sub %g3,%o4,%g3
+5: addxcc %g3,%g3,%g3
+ bcc 2b
+ subcc %g1,1,%g1
+! Got carry from n. Subtract next step to cancel this carry.
+ bne 4b
+ addcc %o2,%o2,%o2 ! shift n1n0 and a 0-bit in lsb
+ sub %g3,%o4,%g3
+3: xnor %o2,0,%o2
+ mov %g3,%i0
+ mov %i3,%o1
+ mov 32,%g1
+ subcc %i0,%o4,%g0
+1: bcs 5f
+ addxcc %o1,%o1,%o1 ! shift n1n0 and a q-bit in lsb
+ sub %i0,%o4,%i0 ! this kills msb of n
+ addx %i0,%i0,%i0 ! so this cannot give carry
+ subcc %g1,1,%g1
+2: bne 1b
+ subcc %i0,%o4,%g0
+ bcs 3f
+ addxcc %o1,%o1,%o1 ! shift n1n0 and a q-bit in lsb
+ b 3f
+ sub %i0,%o4,%i0 ! this kills msb of n
+4: sub %i0,%o4,%i0
+5: addxcc %i0,%i0,%i0
+ bcc 2b
+ subcc %g1,1,%g1
+! Got carry from n. Subtract next step to cancel this carry.
+ bne 4b
+ addcc %o1,%o1,%o1 ! shift n1n0 and a 0-bit in lsb
+ sub %i0,%o4,%i0
+3: xnor %o1,0,%o1
+ b .LL86
+ mov %o1,%l1
+.LL45:
+ cmp %i2,%i0
+ bleu .LL51
+ sethi %hi(65535),%o0
+ b .LL78
+ mov 0,%o1
+.LL51:
+ or %o0,%lo(65535),%o0
+ cmp %i2,%o0
+ bgu .LL58
+ mov %i2,%o1
+ cmp %i2,256
+ addx %g0,-1,%o0
+ b .LL64
+ and %o0,8,%o2
+.LL58:
+ sethi %hi(16777215),%o0
+ or %o0,%lo(16777215),%o0
+ cmp %i2,%o0
+ bgu .LL64
+ mov 24,%o2
+ mov 16,%o2
+.LL64:
+ srl %o1,%o2,%o0
+ sethi %hi(__clz_tab),%o1
+ or %o1,%lo(__clz_tab),%o1
+ ldub [%o0+%o1],%o0
+ add %o0,%o2,%o0
+ mov 32,%o1
+ subcc %o1,%o0,%o3
+ bne,a .LL72
+ sub %o1,%o3,%o1
+ cmp %i0,%i2
+ bgu .LL74
+ cmp %i3,%o4
+ blu .LL78
+ mov 0,%o1
+.LL74:
+ b .LL78
+ mov 1,%o1
+.LL72:
+ sll %i2,%o3,%o2
+ srl %o4,%o1,%o0
+ or %o2,%o0,%i2
+ sll %o4,%o3,%o4
+ srl %i0,%o1,%o2
+ sll %i0,%o3,%o0
+ srl %i3,%o1,%o1
+ or %o0,%o1,%i0
+ sll %i3,%o3,%i3
+ mov %i0,%o1
+ mov 32,%g1
+ subcc %o2,%i2,%g0
+1: bcs 5f
+ addxcc %o1,%o1,%o1 ! shift n1n0 and a q-bit in lsb
+ sub %o2,%i2,%o2 ! this kills msb of n
+ addx %o2,%o2,%o2 ! so this cannot give carry
+ subcc %g1,1,%g1
+2: bne 1b
+ subcc %o2,%i2,%g0
+ bcs 3f
+ addxcc %o1,%o1,%o1 ! shift n1n0 and a q-bit in lsb
+ b 3f
+ sub %o2,%i2,%o2 ! this kills msb of n
+4: sub %o2,%i2,%o2
+5: addxcc %o2,%o2,%o2
+ bcc 2b
+ subcc %g1,1,%g1
+! Got carry from n. Subtract next step to cancel this carry.
+ bne 4b
+ addcc %o1,%o1,%o1 ! shift n1n0 and a 0-bit in lsb
+ sub %o2,%i2,%o2
+3: xnor %o1,0,%o1
+ mov %o2,%i0
+ wr %g0,%o1,%y ! SPARC has 0-3 delay insn after a wr
+ sra %o4,31,%g2 ! Do not move this insn
+ and %o1,%g2,%g2 ! Do not move this insn
+ andcc %g0,0,%g1 ! Do not move this insn
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,%o4,%g1
+ mulscc %g1,0,%g1
+ add %g1,%g2,%o0
+ rd %y,%o2
+ cmp %o0,%i0
+ bgu,a .LL78
+ add %o1,-1,%o1
+ bne,a .LL50
+ mov 0,%o2
+ cmp %o2,%i3
+ bleu .LL50
+ mov 0,%o2
+ add %o1,-1,%o1
+.LL78:
+ mov 0,%o2
+.LL50:
+ mov %o1,%l1
+.LL86:
+ mov %o2,%l0
+ mov %l0,%i0
+ mov %l1,%i1
+ cmp %l4,0
+ be .LL81
+ sub %g0,%i1,%o0
+ mov %o0,%l3
+ subcc %g0,%o0,%g0
+ sub %g0,%i0,%o0
+ subx %o0,0,%l2
+ mov %l2,%i0
+ mov %l3,%i1
+.LL81:
+ ret
+ restore
diff --git a/include/kernel/time.h b/include/kernel/time.h
index 3e59149e7655b45f22d5ef094795e387c88dd07c..cb74b543269990e5e319d5c2b2be2b2e23ef5eab 100644
--- a/include/kernel/time.h
+++ b/include/kernel/time.h
@@ -25,22 +25,30 @@
#include <kernel/clocksource.h>
-#if 0
-struct timespec {
- uint32_t tv_sec; /* seconds */
- uint32_t tv_nsec; /* nanoseconds */
-};
-#endif
/* we use the compiler-defined struct timespec at this time, but we can
* at least verify the size of the types to see if we are compatible
*/
-compile_time_assert((member_size(struct timespec, tv_sec) == sizeof(uint32_t)),
+compile_time_assert((member_size(struct timespec, tv_sec) == sizeof(int32_t)),
TIMESPEC_SEC_SIZE_MISMATCH);
-compile_time_assert((member_size(struct timespec, tv_nsec) == sizeof(uint32_t)),
+compile_time_assert((member_size(struct timespec, tv_nsec) == sizeof(int32_t)),
TIMESPEC_NSEC_SIZE_MISMATCH);
+#define MSEC_PER_SEC 1000L
+#define USEC_PER_MSEC 1000L
+#define NSEC_PER_USEC 1000L
+#define NSEC_PER_MSEC 1000000L
+#define USEC_PER_SEC 1000000L
+#define NSEC_PER_SEC 1000000000L
+
+#define KTIME_MAX (~(1LL << 63))
+#define KTIME_SEC_MAX (KTIME_MAX / NSEC_PER_SEC)
+
+/* ktime is nanoseconds since boot */
+typedef int64_t ktime;
+
+
struct timekeeper {
struct clocksource *clock;
uint32_t readout_ns; /* readout time overhead in ns */
@@ -48,6 +56,34 @@ struct timekeeper {
+
+ktime ktime_get(void);
+ktime ktime_set(const unsigned long sec, const unsigned long nsec);
+ktime timespec_to_ktime(struct timespec ts);
+
+ktime ktime_add(const ktime t1, const ktime t2);
+ktime ktime_sub(const ktime later, const ktime earlier);
+ktime ktime_add_ns(const ktime t, const uint64_t nsec);
+ktime ktime_sub_ns(const ktime t, const uint64_t nsec);
+ktime ktime_add_us(const ktime t, const uint64_t usec);
+ktime ktime_add_ms(const ktime t, const uint64_t msec);
+ktime ktime_sub_us(const ktime t, const uint64_t usec);
+ktime ktime_sub_ms(const ktime t, const uint64_t msec);
+int ktime_compare(const ktime t1, const ktime t2);
+bool ktime_after(const ktime t1, const ktime t2);
+bool ktime_before(const ktime t1, const ktime t2);
+int64_t ktime_delta(const ktime later, const ktime earlier);
+int64_t ktime_us_delta(const ktime later, const ktime earlier);
+int64_t ktime_ms_delta(const ktime later, const ktime earlier);
+int64_t ktime_to_us(const ktime t);
+int64_t ktime_to_ms(const ktime t);
+ktime us_to_ktime(const int64_t usec);
+ktime ms_to_ktime(const int64_t msec);
+
+
+struct timespec timespec_add(struct timespec t1, struct timespec t2);
+struct timespec ns_to_timespec(const int64_t nsec);
+struct timespec timespec_add_ns(struct timespec ts, int64_t nsec);
struct timespec get_uptime(void);
struct timespec get_ktime(void);
diff --git a/kernel/time.c b/kernel/time.c
index dd297b1565f26bca4177cf12a0b18456e2da0413..386472494501ba9fbff5a69030cbde60ec4de5ca 100644
--- a/kernel/time.c
+++ b/kernel/time.c
@@ -77,6 +77,15 @@ EXPORT_SYMBOL(get_ktime);
+
+
+
+
+
+
+
+
+
/**
* @brief returns the number of seconds elapsed between time1 and time0
*
@@ -105,6 +114,9 @@ EXPORT_SYMBOL(difftime);
* @param ts2 a struct timespec
*
* @returns the time delta in nanoseconds, represented as double
+ *
+ * XXX we really need a 64 bit ktime_t or overflows are very likely here
+ * TODO need software implementation of 64 bit add/sub/mult
*/
double difftime_ns(const struct timespec time1, const struct timespec time0)
@@ -138,6 +150,278 @@ static void time_init_overhead_calibrate(void)
tk.readout_ns);
}
+/**
+ * @brief normalise a struct timespec so 0 <= tv_nsec < NSEC_PER_SEC
+ */
+
+struct timespec timespec_normalise(struct timespec t)
+{
+ while (t.tv_nsec >= NSEC_PER_SEC) {
+ t.tv_sec++;
+ t.tv_nsec -= NSEC_PER_SEC;
+ }
+
+ while (t.tv_nsec < 0) {
+ t.tv_sec--;
+ t.tv_nsec += NSEC_PER_SEC;
+ }
+
+ return t;
+}
+
+
+/**
+ * @brief add two struct timespec
+ */
+
+struct timespec timespec_add(struct timespec t1, struct timespec t2)
+{
+ t1.tv_sec += t2.tv_sec;
+ t1.tv_nsec += t2.tv_nsec;
+
+ return timespec_normalise(t1);
+}
+EXPORT_SYMBOL(timespec_add);
+
+/**
+ * @brief convert nanoseconds to a struct timespec
+ *
+ * @warn this is guaranteed to produce incorrect results for
+ * nsec >= 2^31 * 10^9 if sizeof(tv_sec) == 4
+ */
+
+struct timespec ns_to_timespec(const int64_t nsec)
+{
+ struct timespec ts = {0};
+
+
+ if (!nsec)
+ return ts;
+
+
+ BUG_ON(nsec > (~(1LL << 31) * NSEC_PER_SEC));
+
+ ts.tv_sec = (typeof(ts.tv_sec)) (nsec / (int64_t) NSEC_PER_SEC);
+
+ ts.tv_nsec = (typeof(ts.tv_nsec)) (nsec - (int64_t) (ts.tv_sec
+ * NSEC_PER_SEC));
+
+ return timespec_normalise(ts);
+}
+EXPORT_SYMBOL(ns_to_timespec);
+
+
+/**
+ * @brief add nanoseconds to a timespec
+ *
+ * @warn this is guaranteed to produce incorrect results for
+ * nsec >= 2^32 * 10^9 if sizeof(tv_sec) == 4
+ */
+
+struct timespec timespec_add_ns(struct timespec ts, int64_t nsec)
+{
+
+ if (!nsec)
+ return ts;
+
+ return timespec_add(ts, ns_to_timespec(nsec));
+}
+EXPORT_SYMBOL(timespec_add_ns);
+
+
+/**
+ * @brief set a ktime from a seconds and nanoseconds
+ * @param sec seconds
+ * @@param nsec nanoseconds
+ *
+ * @returns the ktime representation of the input values
+ *
+ * @note this allows to set ktime to be at most 10^9 * 2 * 2^32 =
+ * 4294967300294967296 ns ~ 136 years which is probably enough :)
+ */
+inline ktime ktime_set(const unsigned long sec, const unsigned long nsec)
+{
+ return (ktime) sec * NSEC_PER_SEC + (ktime) nsec;
+}
+
+
+inline struct timespec ktime_to_timespec(ktime t)
+{
+ return ns_to_timespec(t);
+}
+
+/**
+ * @brief converts a struct timespec to ktime_t
+ */
+
+inline ktime timespec_to_ktime(struct timespec ts)
+{
+ return ktime_set(ts.tv_sec, ts.tv_nsec);
+}
+
+
+/**
+ * @brief compare ktimes
+ *
+ * @returns < 0 if t1 < t2
+ * 0 if t1 == t2
+ * > 0 if t1 > t2
+ */
+
+int ktime_compare(const ktime t1, const ktime t2)
+{
+ if (t1 < t2)
+ return -1;
+
+ if (t1 > t2)
+ return 1;
+
+ return 0;
+}
+
+
+/**
+ * @param see if a ktime t1 is after t2
+ * Return: true if t1 was after t2, false otherwise
+ */
+
+inline bool ktime_after(const ktime t1, const ktime t2)
+{
+ return ktime_compare(t1, t2) > 0;
+}
+
+
+/**
+ * @param see if a ktime t1 is before t2
+ * Return: true if t1 was before t2, false otherwise
+ */
+
+inline bool ktime_before(const ktime t1, const ktime t2)
+{
+ return ktime_compare(t1, t2) < 0;
+}
+
+
+inline ktime ktime_add(const ktime t1, const ktime t2)
+{
+ return t1 + t2;
+}
+
+
+inline ktime ktime_sub(const ktime later, const ktime earlier)
+{
+ return later - earlier;
+}
+
+
+
+inline ktime ktime_add_ns(const ktime t, const uint64_t nsec)
+{
+ return t + nsec;
+}
+
+
+inline ktime ktime_sub_ns(const ktime t, const uint64_t nsec)
+{
+ return t - nsec;
+}
+
+
+inline ktime ktime_add_us(const ktime t, const uint64_t usec)
+{
+ return ktime_add_ns(t, usec * NSEC_PER_USEC);
+}
+
+
+inline ktime ktime_add_ms(const ktime t, const uint64_t msec)
+{
+ return ktime_add_ns(t, msec * NSEC_PER_MSEC);
+}
+
+
+inline ktime ktime_sub_us(const ktime t, const uint64_t usec)
+{
+ return ktime_sub_ns(t, usec * NSEC_PER_USEC);
+}
+
+
+inline ktime ktime_sub_ms(const ktime t, const uint64_t msec)
+{
+ return ktime_sub_ns(t, msec * NSEC_PER_MSEC);
+}
+
+inline int64_t ktime_delta(const ktime later, const ktime earlier)
+{
+ return ktime_sub(later, earlier);
+}
+
+inline int64_t ktime_us_delta(const ktime later, const ktime earlier)
+{
+ return ktime_to_us(ktime_sub(later, earlier));
+}
+
+
+inline int64_t ktime_ms_delta(const ktime later, const ktime earlier)
+{
+ return ktime_to_ms(ktime_sub(later, earlier));
+}
+
+
+inline int64_t ktime_to_us(const ktime t)
+{
+ return t / (int64_t) NSEC_PER_USEC;
+}
+
+
+inline int64_t ktime_to_ms(const ktime t)
+{
+ return t / (int64_t) NSEC_PER_MSEC;
+}
+
+inline ktime us_to_ktime(const int64_t usec)
+{
+ return (ktime) (usec * (int64_t) NSEC_PER_USEC);
+}
+
+inline ktime ms_to_ktime(const int64_t msec)
+{
+ return (ktime) (msec * (int64_t) NSEC_PER_MSEC);
+}
+
+
+
+/**
+ * @brief get current kernel time (== uptime)
+ *
+ * @note if no uptime clock was configured, the result will be 0
+ */
+
+ktime ktime_get(void)
+{
+ ktime ns;
+
+ uint32_t sec;
+ uint32_t nsec;
+
+
+
+ if (!tk.clock)
+ return 0;
+
+ tk.clock->read(&sec, &nsec);
+
+ ns = (ktime) sec * NSEC_PER_SEC + (ktime) nsec;
+
+
+ return ns;
+}
+EXPORT_SYMBOL(ktime_get);
+
+
+
+
+
+
/**
* @brief initialise the timing system