git subrepo clone --branch=develop https://github.com/m4xw/emummc emummc

subrepo:
  subdir:   "emummc"
  merged:   "a9d569594"
upstream:
  origin:   "https://github.com/m4xw/emummc"
  branch:   "develop"
  commit:   "a9d569594"
git-subrepo:
  version:  "0.4.1"
  origin:   "???"
  commit:   "???"

emummc/source/nx/counter.h

@@ -0,0 +1,46 @@
+/**
+ * @file counter.h
+ * @brief AArch64 system counter-timer.
+ * @author fincs
+ * @copyright libnx Authors
+ */
+#pragma once
+#include "../utils/types.h"
+
+/**
+ * @brief Gets the current system tick.
+ * @return The current system tick.
+ */
+static inline u64 armGetSystemTick(void) {
+    u64 ret;
+    __asm__ __volatile__ ("mrs %x[data], cntpct_el0" : [data] "=r" (ret));
+    return ret;
+}
+
+/**
+ * @brief Gets the system counter-timer frequency
+ * @return The system counter-timer frequency, in Hz.
+ */
+static inline u64 armGetSystemTickFreq(void) {
+    u64 ret;
+    __asm__ ("mrs %x[data], cntfrq_el0" : [data] "=r" (ret));
+    return ret;
+}
+
+/**
+ * @brief Converts from nanoseconds to CPU ticks unit.
+ * @param ns Time in nanoseconds.
+ * @return Time in CPU ticks.
+ */
+static inline u64 armNsToTicks(u64 ns) {
+    return (ns * 12) / 625;
+}
+
+/**
+ * @brief Converts from CPU ticks unit to nanoseconds.
+ * @param tick Time in ticks.
+ * @return Time in nanoseconds.
+ */
+static inline u64 armTicksToNs(u64 tick) {
+    return (tick * 625) / 12;
+}