1 files changed, 99 insertions, 0 deletions
diff --git a/libc/arch-arm/bionic/gettimeofday.c b/libc/arch-arm/bionic/gettimeofday.c
new file mode 100644
index 0000000..780d6e8
--- /dev/null
+++ b/libc/arch-arm/bionic/gettimeofday.c
@@ -0,0 +1,99 @@
+/* Copyright (c) 2012, The Linux Foundation. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *    * Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above
+ *     copyright notice, this list of conditions and the following
+ *     disclaimer in the documentation and/or other materials provided
+ *     with the distribution.
+ *   * Neither the name of The Linux Foundation nor the names of its
+ *     contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+ * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
+ * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include <string.h>
+#include <stdint.h>
+#include <sys/time.h>
+#include <machine/cpu-features.h>
+#include <machine/kernel_user_helper.h>
+
+int gettimeofday(struct timeval *tv, struct timezone *tz)
+{
+	unsigned prelock, postlock;
+
+	/*
+	 * Check if the offset in the kernel user helper page has
+	 * the flag set appropriately to show that this feature is
+	 * enabled in the kernel.  If not, default to the original
+	 * gettimeofday system call.
+	 */
+	if (__kuser_gtod_feature != __kuser_gtod_feature_flag)
+		return gettimeofday_syscall(tv, tz);
+
+	if (tv) {
+		struct gtod_t dgtod;
+		uint32_t nscount, cycleoffset;
+		uint64_t cycle_delta;
+		uint32_t tmp = 0;
+
+		do {
+			prelock = __kuser_gtod_seqnum;
+
+			dgtod.cycle_last = __kuser_gtod_cycle_last;
+			dgtod.mask = __kuser_gtod_mask;
+			dgtod.mult = __kuser_gtod_mult;
+			dgtod.shift = __kuser_gtod_shift;
+			dgtod.tv_sec = __kuser_gtod_tv_sec;
+			dgtod.tv_nsec = __kuser_gtod_tv_nsec;
+
+			cycleoffset = __kuser_gtod_offset;
+			cycleoffset += __kuser_gtod_cycle_base;
+			nscount = *(uint32_t *)cycleoffset;
+
+			postlock = __kuser_gtod_seqnum;
+		} while (prelock != postlock);
+
+		cycle_delta = (nscount - dgtod.cycle_last) & dgtod.mask;
+		dgtod.tv_nsec += (cycle_delta * dgtod.mult) >> dgtod.shift;
+		while (dgtod.tv_nsec >= NSEC_PER_SEC) {
+			dgtod.tv_sec += 1;
+			dgtod.tv_nsec -= NSEC_PER_SEC;
+		}
+
+		tv->tv_sec = dgtod.tv_sec;
+		asm("   movw   %[tmp], #0x4dd3\n\t"
+		    "   movt   %[tmp], #0x1062\n\t"
+		    "   umull  %[tmp], %[x], %[y], %[tmp]\n\t"
+		    "   lsr    %[x], %[x], #6\n\t" :
+			[x] "=r" (tv->tv_usec) :
+			[y] "r" (dgtod.tv_nsec), [tmp] "r" (tmp)
+			: );
+	}
+
+	if (tz) {
+		do {
+			prelock = __kuser_gtod_seqnum;
+			tz->tz_minuteswest = __kuser_gtod_tz_minw;
+			tz->tz_dsttime = __kuser_gtod_tz_dst;
+			postlock = __kuser_gtod_seqnum;
+		} while (prelock != postlock);
+	}
+
+	return 0;
+}