1 files changed, 131 insertions, 0 deletions
diff --git a/Marlin/src/HAL/LPC1768/eeprom_flash.cpp b/Marlin/src/HAL/LPC1768/eeprom_flash.cpp
new file mode 100644
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--- /dev/null
+++ b/Marlin/src/HAL/LPC1768/eeprom_flash.cpp
@@ -0,0 +1,131 @@
+/**
+ * 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 TARGET_LPC1768
+
+/**
+ * Emulate EEPROM storage using Flash Memory
+ *
+ * Use a single 32K flash sector to store EEPROM data. To reduce the
+ * number of erase operations a simple "leveling" scheme is used that
+ * maintains a number of EEPROM "slots" within the larger flash sector.
+ * Each slot is used in turn and the entire sector is only erased when all
+ * slots have been used.
+ *
+ * A simple RAM image is used to hold the EEPROM data during I/O operations
+ * and this is flushed to the next available slot when an update is complete.
+ * If RAM usage becomes an issue we could store this image in one of the two
+ * 16Kb I/O buffers (intended to hold DMA USB and Ethernet data, but currently
+ * unused).
+ */
+#include "../../inc/MarlinConfig.h"
+
+#if ENABLED(FLASH_EEPROM_EMULATION)
+
+#include "../shared/eeprom_api.h"
+
+extern "C" {
+  #include <lpc17xx_iap.h>
+}
+
+#ifndef MARLIN_EEPROM_SIZE
+  #define MARLIN_EEPROM_SIZE 0x1000 // 4KB
+#endif
+
+#define SECTOR_START(sector)  ((sector < 16) ? (sector << 12) : ((sector - 14) << 15))
+#define EEPROM_SECTOR 29
+#define SECTOR_SIZE 32768
+#define EEPROM_SLOTS ((SECTOR_SIZE)/(MARLIN_EEPROM_SIZE))
+#define EEPROM_ERASE 0xFF
+#define SLOT_ADDRESS(sector, slot) (((uint8_t *)SECTOR_START(sector)) + slot * (MARLIN_EEPROM_SIZE))
+
+static uint8_t ram_eeprom[MARLIN_EEPROM_SIZE] __attribute__((aligned(4))) = {0};
+static bool eeprom_dirty = false;
+static int current_slot = 0;
+
+size_t PersistentStore::capacity() { return MARLIN_EEPROM_SIZE; }
+
+bool PersistentStore::access_start() {
+  uint32_t first_nblank_loc, first_nblank_val;
+  IAP_STATUS_CODE status;
+
+  // discover which slot we are currently using.
+  __disable_irq();
+  status = BlankCheckSector(EEPROM_SECTOR, EEPROM_SECTOR, &first_nblank_loc, &first_nblank_val);
+  __enable_irq();
+
+  if (status == CMD_SUCCESS) {
+    // sector is blank so nothing stored yet
+    for (int i = 0; i < MARLIN_EEPROM_SIZE; i++) ram_eeprom[i] = EEPROM_ERASE;
+    current_slot = EEPROM_SLOTS;
+  }
+  else {
+    // current slot is the first non blank one
+    current_slot = first_nblank_loc / (MARLIN_EEPROM_SIZE);
+    uint8_t *eeprom_data = SLOT_ADDRESS(EEPROM_SECTOR, current_slot);
+    // load current settings
+    for (int i = 0; i < MARLIN_EEPROM_SIZE; i++) ram_eeprom[i] = eeprom_data[i];
+  }
+  eeprom_dirty = false;
+
+  return true;
+}
+
+bool PersistentStore::access_finish() {
+  if (eeprom_dirty) {
+    IAP_STATUS_CODE status;
+    if (--current_slot < 0) {
+      // all slots have been used, erase everything and start again
+      __disable_irq();
+      status = EraseSector(EEPROM_SECTOR, EEPROM_SECTOR);
+      __enable_irq();
+
+      current_slot = EEPROM_SLOTS - 1;
+    }
+
+    __disable_irq();
+    status = CopyRAM2Flash(SLOT_ADDRESS(EEPROM_SECTOR, current_slot), ram_eeprom, IAP_WRITE_4096);
+    __enable_irq();
+
+    if (status != CMD_SUCCESS) return false;
+    eeprom_dirty = false;
+  }
+  return true;
+}
+
+bool PersistentStore::write_data(int &pos, const uint8_t *value, size_t size, uint16_t *crc) {
+  for (size_t i = 0; i < size; i++) ram_eeprom[pos + i] = value[i];
+  eeprom_dirty = true;
+  crc16(crc, value, size);
+  pos += size;
+  return false;  // return true for any error
+}
+
+bool PersistentStore::read_data(int &pos, uint8_t *value, size_t size, uint16_t *crc, const bool writing/*=true*/) {
+  const uint8_t * const buff = writing ? &value[0] : &ram_eeprom[pos];
+  if (writing) for (size_t i = 0; i < size; i++) value[i] = ram_eeprom[pos + i];
+  crc16(crc, buff, size);
+  pos += size;
+  return false;  // return true for any error
+}
+
+#endif // FLASH_EEPROM_EMULATION
+#endif // TARGET_LPC1768