1 files changed, 117 insertions, 0 deletions
diff --git a/Marlin/src/HAL/LINUX/hardware/Timer.cpp b/Marlin/src/HAL/LINUX/hardware/Timer.cpp
new file mode 100644
index 0000000..9f0d6a8
--- /dev/null
+++ b/Marlin/src/HAL/LINUX/hardware/Timer.cpp
@@ -0,0 +1,117 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * 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, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * 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.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#ifdef __PLAT_LINUX__
+
+#include "Timer.h"
+#include <stdio.h>
+
+Timer::Timer() {
+  active = false;
+  compare = 0;
+  frequency = 0;
+  overruns = 0;
+  timerid = 0;
+  cbfn = nullptr;
+  period = 0;
+  start_time = 0;
+  avg_error = 0;
+}
+
+Timer::~Timer() {
+  timer_delete(timerid);
+}
+
+void Timer::init(uint32_t sig_id, uint32_t sim_freq, callback_fn* fn) {
+  struct sigaction sa;
+  struct sigevent sev;
+
+  frequency = sim_freq;
+  cbfn = fn;
+
+  sa.sa_flags = SA_SIGINFO;
+  sa.sa_sigaction = Timer::handler;
+  sigemptyset(&sa.sa_mask);
+  if (sigaction(SIGRTMIN, &sa, nullptr) == -1) {
+    return; // todo: handle error
+  }
+
+  sigemptyset(&mask);
+  sigaddset(&mask, SIGRTMIN);
+
+  disable();
+
+  sev.sigev_notify = SIGEV_SIGNAL;
+  sev.sigev_signo = SIGRTMIN;
+  sev.sigev_value.sival_ptr = (void*)this;
+  if (timer_create(CLOCK_REALTIME, &sev, &timerid) == -1) {
+    return; // todo: handle error
+  }
+}
+
+void Timer::start(uint32_t frequency) {
+  setCompare(this->frequency / frequency);
+  //printf("timer(%ld) started\n", getID());
+}
+
+void Timer::enable() {
+  if (sigprocmask(SIG_UNBLOCK, &mask, nullptr) == -1) {
+    return; // todo: handle error
+  }
+  active = true;
+  //printf("timer(%ld) enabled\n", getID());
+}
+
+void Timer::disable() {
+  if (sigprocmask(SIG_SETMASK, &mask, nullptr) == -1) {
+    return; // todo: handle error
+  }
+  active = false;
+}
+
+void Timer::setCompare(uint32_t compare) {
+  uint32_t nsec_offset = 0;
+  if (active) {
+    nsec_offset = Clock::nanos() - this->start_time; // calculate how long the timer would have been running for
+    nsec_offset = nsec_offset < 1000 ? nsec_offset : 0; // constrain, this shouldn't be needed but apparently Marlin enables interrupts on the stepper timer before initialising it, todo: investigate ?bug?
+  }
+  this->compare = compare;
+  uint64_t ns = Clock::ticksToNanos(compare, frequency) - nsec_offset;
+  struct itimerspec its;
+  its.it_value.tv_sec = ns / 1000000000;
+  its.it_value.tv_nsec = ns % 1000000000;
+  its.it_interval.tv_sec = its.it_value.tv_sec;
+  its.it_interval.tv_nsec = its.it_value.tv_nsec;
+
+  if (timer_settime(timerid, 0, &its, nullptr) == -1) {
+    printf("timer(%ld) failed, compare: %d(%ld)\n", getID(), compare, its.it_value.tv_nsec);
+    return; // todo: handle error
+  }
+  //printf("timer(%ld) started, compare: %d(%d)\n", getID(), compare, its.it_value.tv_nsec);
+  this->period = its.it_value.tv_nsec;
+  this->start_time = Clock::nanos();
+}
+
+uint32_t Timer::getCount() {
+  return Clock::nanosToTicks(Clock::nanos() - this->start_time, frequency);
+}
+
+#endif // __PLAT_LINUX__