Fixes for the Arduino DUE HAL (Serial Port, Graphics Display, EEPROM emulation) (#8651)

* Fixing the DUE serial port assignments: Now -1 means the SAM3x USB Device emulating a serial port, and 0 means the USB to serial adapter included as a programming port

* Improving the Fast IO port access implementation on Arduino DUE

* Implemented EEPROM emulation on Due by storing data on the internal FLASH (with wear leveling)

* Implemented a Software SPI for the ST7920 graphics display for the Arduino RAMPS for DUE, as the default one in u8glib is clocking data too fast on ARM, and the display does not understand it.

* Fixing the case where the serial port selected is the USB device

* Adding configuration for the Makerparts 3D printer (www.makerparts.net)

* Tuned MakerParts acceleration on X and Y axis so it never loses steps. Also adjusted pulses per mm to match default hw configuration

* Fine tuned Maximum acceleration for MakerParts printer

* Style cleanup

* Style cleanup (2)

* Style fixes (3)

* Fixing the DUE serial port assignments: Now -1 means the SAM3x USB Device emulating a serial port, and 0 means the USB to serial adapter included as a programming port

* Improving the Fast IO port access implementation on Arduino DUE

* Implemented EEPROM emulation on Due by storing data on the internal FLASH (with wear leveling)

* Implemented a Software SPI for the ST7920 graphics display for the Arduino RAMPS for DUE, as the default one in u8glib is clocking data too fast on ARM, and the display does not understand it.

* Fixing the case where the serial port selected is the USB device

* Adding configuration for the Makerparts 3D printer (www.makerparts.net)

* Tuned MakerParts acceleration on X and Y axis so it never loses steps. Also adjusted pulses per mm to match default hw configuration

* Fine tuned Maximum acceleration for MakerParts printer

* Style cleanup

* Style changes to u8g_dev_st7920_128_64_sw_spi.cpp

* Even more improvements to the FastIO HAL for DUE. Now WRITE() is 2 ASM instructions, if value is constant, and 5 cycles if value is not constant. Previously, it was 7..8 cycles

* After some problems and debugging, seems we need to align the interrupt vector table to 256 bytes, otherwise, the program sometimes stops working

* Moved comments out of macro, otherwise, token pasting does not properly work sometimes

* Improved Software SPI implementation on DUE: Now it honors the selected speed passed to spiInit(). This allows much faster SDCARD access, improving SDCARD menus and reducing latency

* Update u8g_dev_st7920_128_64_sw_spi.cpp

* Disabling EEPROM over FLASH emulatiion if an I2C or SPI EEPROM is present

Marlin/src/HAL/HAL_DUE/HAL_Due.h

@@ -43,13 +43,7 @@
 
 #if SERIAL_PORT == -1
   #define MYSERIAL SerialUSB
-#elif SERIAL_PORT == 0
-  #define MYSERIAL customizedSerial
-#elif SERIAL_PORT == 1
-  #define MYSERIAL customizedSerial
-#elif SERIAL_PORT == 2
-  #define MYSERIAL customizedSerial
-#elif SERIAL_PORT == 3
+#elif SERIAL_PORT >= 0 && SERIAL_PORT <= 4
   #define MYSERIAL customizedSerial
 #endif
 

Marlin/src/HAL/HAL_DUE/HAL_spi_Due.cpp

@@ -52,30 +52,123 @@
   // --------------------------------------------------------------------------
   // software SPI
   // --------------------------------------------------------------------------
+
+  /* ---------------- Delay Cycles routine -------------- */
+
+  /* https://blueprints.launchpad.net/gcc-arm-embedded/+spec/delay-cycles */
+
+  #define nop() __asm__ __volatile__("nop;\n\t":::)
+
+  FORCE_INLINE static void __delay_4cycles(uint32_t cy) { // +1 cycle
+    #if ARCH_PIPELINE_RELOAD_CYCLES<2
+      #define EXTRA_NOP_CYCLES "nop"
+    #else
+      #define EXTRA_NOP_CYCLES ""
+    #endif
+
+    __asm__ __volatile__(
+      ".syntax unified" "\n\t" // is to prevent CM0,CM1 non-unified syntax
+
+      "loop%=:" "\n\t"
+      " subs %[cnt],#1" "\n\t"
+      EXTRA_NOP_CYCLES "\n\t"
+      " bne loop%=" "\n\t"
+      : [cnt]"+r"(cy) // output: +r means input+output
+      : // input:
+      : "cc" // clobbers:
+    );
+  }
+
+  FORCE_INLINE static void DELAY_CYCLES(uint32_t x) {
+
+    if (__builtin_constant_p(x)) {
+
+      #define MAXNOPS 4
+
+      if (x <= (MAXNOPS)) {
+        switch(x) { case 4: nop(); case 3: nop(); case 2: nop(); case 1: nop(); }
+      }
+      else { // because of +1 cycle inside delay_4cycles
+        const uint32_t rem = (x - 1) % (MAXNOPS);
+        switch(rem) { case 3: nop(); case 2: nop(); case 1: nop(); }
+        if ((x = (x - 1) / (MAXNOPS)))
+          __delay_4cycles(x); // if need more then 4 nop loop is more optimal
+      }
+    }
+    else
+      __delay_4cycles(x / 4);
+  }
+
+  /* ---------------- Delay in nanoseconds and in microseconds */
+
+  #define DELAY_NS(x) DELAY_CYCLES( (x) * (F_CPU/1000000) / 1000)
+
+  typedef uint8_t (*pfnSpiTransfer) (uint8_t b);
+
   // bitbanging transfer
-  // run at ~100KHz (necessary for init)
-  static uint8_t spiTransfer(uint8_t b) { // using Mode 0
-    for (int bits = 0; bits < 8; bits++) {
-      if (b & 0x80) {
-        WRITE(MOSI_PIN, HIGH);
-      }
-      else {
-        WRITE(MOSI_PIN, LOW);
-      }
-      b <<= 1;
+  #define SWSPI_BIT_XFER(n) \
+      WRITE(MOSI_PIN, bout & (1 << n)); \
+      WRITE(SCK_PIN, HIGH); /* Sampling point */\
+      /* (implicit by overhead) DELAY_NS(63); 5.3 cycles @ 84mhz */ \
+      bin |= (READ(MISO_PIN) != 0) << n; \
+      WRITE(SCK_PIN, LOW); /* Toggling point*/ \
+      /* (implicit by overhead) DELAY_NS(63); 5.3 cycles @ 84mhz */
+
+  // run at ~8 .. ~10Mhz
+  static uint8_t spiTransfer0(uint8_t bout) { // using Mode 0
+    volatile uint8_t bin = 0; /* volatile to disable deferred processing */
+    SWSPI_BIT_XFER(7);
+    SWSPI_BIT_XFER(6);
+    SWSPI_BIT_XFER(5);
+    SWSPI_BIT_XFER(4);
+    SWSPI_BIT_XFER(3);
+    SWSPI_BIT_XFER(2);
+    SWSPI_BIT_XFER(1);
+    SWSPI_BIT_XFER(0);
+    return bin;
+  }
+
+  // run at ~4Mhz
+  static uint8_t spiTransfer1(uint8_t b) { // using Mode 0
+    int bits = 8;
+    do {
+      WRITE(MOSI_PIN, b & 0x80);
+      b <<= 1; // little setup time
 
       WRITE(SCK_PIN, HIGH);
-      delayMicroseconds(5U);
+      DELAY_NS(125); // 10 cycles @ 84mhz
+
+      b |= (READ(MISO_PIN) != 0);
 
-      if (READ(MISO_PIN)) {
-        b |= 1;
-      }
       WRITE(SCK_PIN, LOW);
-      delayMicroseconds(5U);
-    }
+      DELAY_NS(125); // 10 cycles @ 84mhz
+    } while (--bits);
     return b;
   }
 
+  // all the others
+  static uint32_t spiDelayCyclesX4 = (F_CPU/1000000); // 4uS => 125khz
+
+  static uint8_t spiTransferX(uint8_t b) { // using Mode 0
+    int bits = 8;
+    do {
+      WRITE(MOSI_PIN, b & 0x80);
+      b <<= 1; // little setup time
+
+      WRITE(SCK_PIN, HIGH);
+      __delay_4cycles(spiDelayCyclesX4);
+
+      b |= (READ(MISO_PIN) != 0);
+
+      WRITE(SCK_PIN, LOW);
+      __delay_4cycles(spiDelayCyclesX4);
+    } while (--bits);
+    return b;
+  }
+
+  // Use the generic one
+  static pfnSpiTransfer spiTransfer = spiTransferX;
+
   void spiBegin() {
     SET_OUTPUT(SS_PIN);
     WRITE(SS_PIN, HIGH);
@@ -84,8 +177,30 @@
     SET_OUTPUT(MOSI_PIN);
   }
 
+  /**
+   * spiRate should be
+   *  0 :  8 - 10 MHz
+   *  1 :  4 - 5 MHz
+   *  2 :  2 - 2.5 MHz
+   *  3 :  1 - 1.25 MHz
+   *  4 :  500 - 625 kHz
+   *  5 :  250 - 312 kHz
+   *  6 :  125 - 156 kHz
+   */
   void spiInit(uint8_t spiRate) {
-    UNUSED(spiRate);
+    switch (spiRate) {
+      case 0:
+        spiTransfer = spiTransfer0;
+        break;
+      case 1:
+        spiTransfer = spiTransfer1;
+        break;
+      default:
+        spiDelayCyclesX4 = (F_CPU/1000000) >> (6 - spiRate);
+        spiTransfer = spiTransferX;
+        break;
+    }
+
     WRITE(SS_PIN, HIGH);
     WRITE(MOSI_PIN, HIGH);
     WRITE(SCK_PIN, LOW);
@@ -137,6 +252,9 @@
     UNUSED(response);
     WRITE(SS_PIN, HIGH);
   }
+
+  #pragma GCC reset_options
+
 #else
   // --------------------------------------------------------------------------
   // hardware SPI

Marlin/src/HAL/HAL_DUE/InterruptVectors_Due.cpp

@@ -35,9 +35,11 @@
 #include "HAL_Due.h"
 #include "InterruptVectors_Due.h"
 
-/* The relocated Exception/Interrupt Table - Must be aligned to 128bytes,
-   as bits 0-6 on VTOR register are reserved and must be set to 0 */
-__attribute__ ((aligned(128)))
+/* The relocated Exception/Interrupt Table - According to the ARM
+   reference manual, alignment to 128 bytes should suffice, but in
+   practice, we need alignment to 256 bytes to make this work in all
+   cases */
+__attribute__ ((aligned(256)))
 static DeviceVectors ram_tab = { NULL };
 
 /**

Marlin/src/HAL/HAL_DUE/fastio_Due.h

@@ -30,6 +30,10 @@
  * Description: Fast IO functions for Arduino Due and compatible (SAM3X8E)
  *
  * For ARDUINO_ARCH_SAM
+ * Note the code here was specifically crafted by disassembling what GCC produces
+ * out of it, so GCC is able to optimize it out as much as possible to the least
+ * amount of instructions. Be very carefull if you modify them, as "clean code"
+ * leads to less efficient compiled code!!
  */
 
 #ifndef _FASTIO_DUE_H
@@ -55,13 +59,20 @@
 #define _READ(IO) ((bool)(DIO ## IO ## _WPORT -> PIO_PDSR & (MASK(DIO ## IO ## _PIN))))
 
 /// Write to a pin
-#define _WRITE_VAR(IO, v) do {  if (v) {g_APinDescription[IO].pPort->PIO_SODR = g_APinDescription[IO].ulPin; } \
-                                    else {g_APinDescription[IO].pPort->PIO_CODR = g_APinDescription[IO].ulPin; } \
-                                 } while (0)
+#define _WRITE_VAR(IO, v)  do { \
+  volatile Pio* port = g_APinDescription[IO].pPort; \
+  uint32_t mask = g_APinDescription[IO].ulPin; \
+  if (v) port->PIO_SODR = mask; \
+  else port->PIO_CODR = mask; \
+} while(0)
 
-#define _WRITE(IO, v) do {  if (v) {DIO ## IO ## _WPORT -> PIO_SODR = MASK(DIO ## IO ##_PIN); } \
-                                else {DIO ##  IO ## _WPORT -> PIO_CODR = MASK(DIO ## IO ## _PIN); }; \
-                             } while (0)
+/// Write to a pin
+#define _WRITE(IO, v) do { \
+  volatile Pio* port = (DIO ##  IO ## _WPORT); \
+  uint32_t mask = MASK(DIO ## IO ## _PIN); \
+  if (v) port->PIO_SODR = mask; \
+  else port->PIO_CODR = mask; \
+} while(0)
 
 /// toggle a pin
 #define _TOGGLE(IO)  _WRITE(IO, !READ(IO))

Marlin/src/HAL/HAL_DUE/persistent_store_impl.cpp

@@ -6,6 +6,8 @@
 
 #if ENABLED(EEPROM_SETTINGS)
 
+extern void eeprom_flush(void);
+
 namespace HAL {
 namespace PersistentStore {
 
@@ -14,6 +16,9 @@ bool access_start() {
 }
 
 bool access_finish(){
+#if DISABLED(I2C_EEPROM) && DISABLED(SPI_EEPROM)
+  eeprom_flush();
+#endif
   return true;
 }
 

Marlin/src/HAL/HAL_DUE/spi_pins.h

@@ -53,6 +53,7 @@
   #define MOSI_PIN          51
 #endif
 
-#define SS_PIN            SDSS // A.28, A.29, B.21, C.26, C.29
+/* A.28, A.29, B.21, C.26, C.29 */
+#define SS_PIN            SDSS
 
 #endif /* SPI_PINS_H_ */