[ion] add millis() and micros() using systick on device

ion/include/ion.h

@@ -27,6 +27,8 @@ namespace Ion {
 
 void msleep(long ms);
 void usleep(long us);
+extern "C" long millis();
+extern "C" long micros();
 
 const char * serialNumber();
 const char * softwareVersion();

ion/src/blackbox/ion.cpp

@@ -3,3 +3,17 @@
 
 void Ion::msleep(long ms) {
 }
+
+#include <chrono>
+
+static auto start = std::chrono::high_resolution_clock::now();
+
+long Ion::millis() {
+  auto elapsed = std::chrono::high_resolution_clock::now() - start;
+  return std::chrono::duration_cast<std::chrono::milliseconds>(elapsed).count();
+}
+
+long Ion::micros() {
+  auto elapsed = std::chrono::high_resolution_clock::now() - start;
+  return std::chrono::duration_cast<std::chrono::microseconds>(elapsed).count();
+}

ion/src/device/boot/isr.c

@@ -28,7 +28,7 @@ ISR InitialisationVector[INITIALISATION_VECTOR_SIZE]
   0, // DebugMonitor service routine,
   0, // Reserved
   0, // PendSV service routine,
-  0, // SysTick service routine
+  sysTick, // SysTick service routine
   0, // WWDG service routine
   0, // PVD service routine
   0, // TampStamp service routine

ion/src/device/boot/rt0.cpp

@@ -92,3 +92,9 @@ void start() {
 
   abort();
 }
+
+volatile long millis_elapsed = 0;
+
+void __attribute__((interrupt)) sysTick() {
+  millis_elapsed++;
+}

ion/src/device/boot/rt0.h

@@ -4,4 +4,6 @@
 void start();
 void abort();
 
+void sysTick();
+
 #endif

ion/src/device/device.cpp

@@ -39,6 +39,22 @@ void Ion::usleep(long us) {
   }
 }
 
+extern volatile long millis_elapsed;
+
+long Ion::millis() {
+  return millis_elapsed;
+}
+
+long Ion::micros() {
+    uint32_t c1 = CM4.STCVR()->getCURRENT();
+    uint32_t ms1 = millis_elapsed;
+    uint32_t c2 = CM4.STCVR()->getCURRENT();
+    uint32_t ms2 = millis_elapsed;
+    uint32_t load = CM4.STRVR()->getRELOAD();
+
+    return ((c1 > c2) ? ms1 : ms2) * 1000 + ((load - c2) * 1000) / (load + 1);
+}
+
 uint32_t Ion::crc32(const uint32_t * data, size_t length) {
   bool initialCRCEngineState = RCC.AHB1ENR()->getCRCEN();
   RCC.AHB1ENR()->setCRCEN(true);
@@ -184,9 +200,17 @@ void initPeripherals() {
 #endif
   Console::Device::init();
   SWD::Device::init();
+
+  CM4.STRVR()->setRELOAD(11999);
+  CM4.STCVR()->setCURRENT(0);
+  CM4.STCSR()->setCLKSOURCE(CM4::STCSR::CLKSOURCE::AHB_DIV8);
+  CM4.STCSR()->setTICKINT(true);
+  CM4.STCSR()->setENABLE(true);
 }
 
 void shutdownPeripherals(bool keepLEDAwake) {
+  CM4.STCSR()->setENABLE(false);
+
   SWD::Device::shutdown();
   Console::Device::shutdown();
 #if USE_SD_CARD

ion/src/device/device.h

@@ -19,6 +19,8 @@ void shutdownPeripherals(bool keepLEDAwake = false);
 void initClocks();
 void shutdownClocks(bool keepLEDAwake = false);
 
+void sysTick();
+
 /* The serial number is 96 bits long. That's equal to 16 digits in base 64. We
  * expose a convenient "copySerialNumber" routine which can be called without
  * using a static variable (and therefore without a .bss section). This is used

ion/src/device/regs/cm4.h

@@ -40,14 +40,39 @@ public:
     REGS_BOOL_FIELD(SLEEPDEEP, 2);
   };
 
+  class STCSR : public Register32 {
+  public:
+    enum class CLKSOURCE : uint8_t {
+      AHB_DIV8 = 0,
+      AHB = 1
+    };
+    REGS_BOOL_FIELD(COUNTFLAG, 16);
+    REGS_TYPE_FIELD(CLKSOURCE, 2, 2);
+    REGS_BOOL_FIELD(TICKINT, 1);
+    REGS_BOOL_FIELD(ENABLE, 0);
+  };
+
+  class STRVR : public Register32 {
+  public:
+    REGS_FIELD(RELOAD, uint32_t, 23, 0);
+  };
+
+  class STCVR : public Register32 {
+  public:
+    REGS_FIELD(CURRENT, uint32_t, 23, 0);
+  };
+
   constexpr CM4() {};
-  REGS_REGISTER_AT(VTOR, 0x08);
-  REGS_REGISTER_AT(AIRCR, 0x0C);
-  REGS_REGISTER_AT(SCR, 0x10);
-  REGS_REGISTER_AT(CPACR, 0x88);
+  REGS_REGISTER_AT(STCSR, 0x10);
+  REGS_REGISTER_AT(STRVR, 0x14);
+  REGS_REGISTER_AT(STCVR, 0x18);
+  REGS_REGISTER_AT(VTOR, 0xD08);
+  REGS_REGISTER_AT(AIRCR, 0xD0C);
+  REGS_REGISTER_AT(SCR, 0xD10);
+  REGS_REGISTER_AT(CPACR, 0xD88);
 private:
   constexpr uint32_t Base() const {
-    return 0xE000ED00;
+    return 0xE000E000;
   }
 };
 

ion/src/device/regs/register.h

@@ -50,7 +50,7 @@ typedef Register<uint32_t> Register32;
 typedef Register<uint64_t> Register64;
 
 #define REGS_FIELD_R(name,type,high,low) type get##name() volatile { return (type)getBitRange(high,low); };
-#define REGS_FIELD_W(name,type,high,low) void set##name(type v) volatile { static_assert(sizeof(type) <= 2, "Invalid size"); setBitRange(high, low, static_cast<uint16_t>(v)); };
+#define REGS_FIELD_W(name,type,high,low) void set##name(type v) volatile { static_assert(sizeof(type) <= 4, "Invalid size"); setBitRange(high, low, static_cast<uint32_t>(v)); };
 #define REGS_FIELD(name,type,high,low) REGS_FIELD_R(name,type,high,low); REGS_FIELD_W(name,type,high,low);
 #define REGS_TYPE_FIELD(name,high,low) REGS_FIELD(name,name,high,low)
 #define REGS_BOOL_FIELD(name,bit) REGS_FIELD(name,bool,bit,bit)

ion/src/device/usb/calculator.cpp

@@ -9,6 +9,7 @@ namespace USB {
 namespace Device {
 
 void Calculator::PollAndReset(bool exitWithKeyboard) {
+  CM4.STCSR()->setTICKINT(false);
   char serialNumber[Ion::Device::SerialNumberLength+1];
   Ion::Device::copySerialNumber(serialNumber);
   Calculator c(serialNumber);
@@ -37,6 +38,7 @@ void Calculator::PollAndReset(bool exitWithKeyboard) {
      * will enter the newly flashed firmware. */
     Ion::Device::jumpReset();
   }
+  CM4.STCSR()->setTICKINT(true);
 }
 
 Descriptor * Calculator::descriptor(uint8_t type, uint8_t index) {

ion/src/emscripten/main.cpp

@@ -2,6 +2,9 @@
 #include "display.h"
 #include "events_keyboard.h"
 #include "../../../apps/global_preferences.h"
+extern "C" {
+#include <SDL/SDL.h>
+}
 
 extern "C" {
 const char * IonSoftwareVersion();
@@ -21,3 +24,7 @@ int main(int argc, char * argv[]) {
 
 void Ion::msleep(long ms) {
 }
+
+long Ion::millis() {
+  return SDL_GetTicks();
+}

ion/src/simulator/init.cpp

@@ -116,3 +116,19 @@ void Ion::msleep(long ms) {
     }
   }
 }
+
+static auto start = std::chrono::high_resolution_clock::now();
+
+long Ion::millis() {
+  sDisplay->redraw();
+  Fl::wait(0);
+  auto elapsed = std::chrono::high_resolution_clock::now() - start;
+  return std::chrono::duration_cast<std::chrono::milliseconds>(elapsed).count();
+}
+
+long Ion::micros() {
+  sDisplay->redraw();
+  Fl::wait(0);
+  auto elapsed = std::chrono::high_resolution_clock::now() - start;
+  return std::chrono::duration_cast<std::chrono::microseconds>(elapsed).count();
+}