Eeprom in external SPI flash (#7)

tested over the weekend - works great

* Enable EEPROM auto init as we will probably start with invalid data in flash.

* Fix XPT2046 to begin/end with it's soft spi pins when needed and to not block SPI2 and vice versa.

* Added SPIFlash class to STM32F1 hal.

* Added persistent_store_spi_flash and updated persistent_store_sdcard to still be default.

* Added required config to pins_MKS_ROBIN_NANO.h.

Marlin/Configuration.h

@@ -1448,7 +1448,7 @@
 //#define DISABLE_M503        // Saves ~2700 bytes of PROGMEM. Disable for release!
 #define EEPROM_CHITCHAT       // Give feedback on EEPROM commands. Disable to save PROGMEM.
 #if ENABLED(EEPROM_SETTINGS)
-  //#define EEPROM_AUTO_INIT  // Init EEPROM automatically on any errors.
+  #define EEPROM_AUTO_INIT  // Init EEPROM automatically on any errors.
 #endif
 
 //

Marlin/src/HAL/HAL_STM32F1/persistent_store_sdcard.cpp

@@ -29,7 +29,7 @@
 
 #include "../../inc/MarlinConfig.h"
 
-#if ENABLED(EEPROM_SETTINGS) && NONE(FLASH_EEPROM_EMULATION, SPI_EEPROM, I2C_EEPROM)
+#if ENABLED(EEPROM_SETTINGS) && NONE(SPI_FLASH_EEPROM_EMULATION, FLASH_EEPROM_EMULATION, SPI_EEPROM, I2C_EEPROM)
 
 #include "../shared/persistent_store_api.h"
 

Marlin/src/HAL/HAL_STM32F1/persistent_store_spi_flash.cpp

@@ -0,0 +1,65 @@
+#ifdef __STM32F1__
+#include "../../inc/MarlinConfig.h"
+
+#if BOTH(EEPROM_SETTINGS, SPI_FLASH_EEPROM_EMULATION)
+
+    #include "../shared/persistent_store_api.h"
+    #include <SPI.h>
+    #include "spi_flash.h"
+
+    #define SPI_FLASH_EEPROM_SIZE 0x1000 // 4K - do not change!
+
+    #ifndef E2END
+    #define E2END SPI_FLASH_EEPROM_SIZE - 1
+    #endif
+
+    static char __attribute__ ((aligned(4))) _eeprom_data[SPI_FLASH_EEPROM_SIZE];
+
+    SPIClass _spi(SPI_FLASH_DEVICE);
+    hal::SPIFlash _flash(_spi, SPI_FLASH_CS_PIN);
+
+    bool PersistentStore::access_start()
+    {
+        _flash.begin();
+        _flash.read_array(SPI_FLASH_EEPROM_OFFSET,  _eeprom_data, SPI_FLASH_EEPROM_SIZE);
+        _flash.end();
+    }
+
+    bool PersistentStore::access_finish()
+    {
+        _flash.begin();
+        _flash.erase_4K(SPI_FLASH_EEPROM_OFFSET);
+        _flash.write_array(SPI_FLASH_EEPROM_OFFSET,  _eeprom_data, SPI_FLASH_EEPROM_SIZE);
+        _flash.end();
+    }
+
+    bool PersistentStore::write_data(int &pos, const uint8_t *value, size_t size, uint16_t *crc)
+    {
+        for (size_t i = 0; i < size; i++)
+        {
+            _eeprom_data[pos + i] = value[i];
+        }
+        crc16(crc, value, size);
+        pos += size;
+        return false;
+    }
+
+    bool PersistentStore::read_data(int &pos, uint8_t* value, const size_t size, uint16_t *crc, const bool writing/*=true*/)
+    {
+        for (size_t i = 0; i < size; i++)
+        {
+            uint8_t c = _eeprom_data[pos + i];
+            if (writing) value[i] = c;
+            crc16(crc, &c, 1);
+        }
+        pos += size;
+        return false;
+    }
+
+    size_t PersistentStore::capacity()
+    {
+        return SPI_FLASH_EEPROM_SIZE; 
+    }
+
+#endif
+#endif

Marlin/src/HAL/HAL_STM32F1/spi_flash.cpp

@@ -0,0 +1,279 @@
+#include "spi_flash.h"
+
+namespace hal
+{
+    constexpr size_t SPIFLASH_PAGESIZE = 256;
+
+    enum SPICommand
+    {
+        WRITEENABLE      = 0x06,
+        WRITEDISABLE     = 0x04,
+        BLOCKERASE_4K    = 0x20,
+        BLOCKERASE_32K   = 0x52,
+        BLOCKERASE_64K   = 0xD8,
+        CHIPERASE        = 0x60,
+        STATUSREAD       = 0x05,
+        STATUSWRITE      = 0x01,
+        ARRAYREAD        = 0x0B,
+        ARRAYREADLOWFREQ = 0x03,
+        SLEEP            = 0xB9,
+        WAKE             = 0xAB,
+        BYTEPAGEPROGRAM  = 0x02,
+        IDREAD           = 0x9F,
+        MACREAD          = 0x4B
+    };
+
+    SPIFlash::SPIFlash(SPIClass &spi_instance, uint8_t cs_pin, uint16_t chip_id)
+    : m_spi(spi_instance)
+    , m_cs_pin(cs_pin)
+    , m_chip_id(chip_id)
+    {
+    }
+
+    void SPIFlash::select()
+    {
+        m_spi.beginTransaction(m_settings);
+        digitalWrite(m_cs_pin, LOW);
+    }
+
+    void SPIFlash::unselect()
+    {
+        digitalWrite(m_cs_pin, HIGH);
+        m_spi.endTransaction();
+    }
+
+    boolean SPIFlash::begin()
+    {
+        pinMode(m_cs_pin, OUTPUT);
+        m_spi.begin();
+        m_settings = SPISettings(25000000, MSBFIRST, SPI_MODE0);
+
+        unselect();
+        wakeup();
+
+        if (m_chip_id == 0 || read_chip_id() == m_chip_id)
+        {
+            command(SPICommand::STATUSWRITE, true);
+            m_spi.transfer(0);
+            unselect();
+            return true;
+        }
+
+        return false;
+    }
+
+    uint16_t SPIFlash::read_chip_id()
+    {
+        command(SPICommand::IDREAD);
+        uint16_t chip_id = m_spi.transfer(0) << 8;
+        chip_id |= m_spi.transfer(0);
+        unselect();
+        return chip_id;
+    }
+
+    uint8_t SPIFlash::read(uint32_t addr)
+    {
+        command(SPICommand::ARRAYREADLOWFREQ);
+        m_spi.transfer(addr >> 16);
+        m_spi.transfer(addr >> 8);
+        m_spi.transfer(addr);
+        uint8_t result = m_spi.transfer(0);
+        unselect();
+        return result;
+    }
+
+    void SPIFlash::read_array(uint32_t addr, void* buf, uint16_t len)
+    {
+        command(SPICommand::ARRAYREAD);
+        m_spi.transfer(addr >> 16);
+        m_spi.transfer(addr >> 8);
+        m_spi.transfer(addr);
+        m_spi.transfer(0); // dummy 8 clocks
+
+        for (uint16_t i = 0; i < len; ++i)
+        {
+            ((uint8_t*)buf)[i] = m_spi.transfer(0);
+        }
+
+        unselect();
+    }
+
+    void SPIFlash::read_array_dma(uint32_t addr, void* buf, uint16_t len)
+    {
+        command(SPICommand::ARRAYREAD);
+        m_spi.transfer(addr >> 16);
+        m_spi.transfer(addr >> 8);
+        m_spi.transfer(addr);
+        m_spi.transfer(0); // dummy 8 clocks
+
+        m_spi.dmaTransfer(nullptr, buf, len);
+
+        for (uint16_t i = 0; i < len; ++i)
+        {
+            ((uint8_t*)buf)[i] = m_spi.transfer(0);
+        }
+
+        unselect();
+    }
+
+    void SPIFlash::command(uint8_t cmd, bool write)
+    {
+        if (cmd != SPICommand::WAKE)
+        {
+            while(busy());
+        }
+
+        if (write)
+        {
+            select();
+            m_spi.transfer(SPICommand::WRITEENABLE);
+            unselect();
+            while(busy());
+        }
+
+        select();
+        m_spi.transfer(cmd);
+    }
+
+    boolean SPIFlash::busy()
+    {
+        return read_status() & 1;
+    }
+
+    boolean SPIFlash::write_enable_latch()
+    {
+        return read_status() & 2;
+    }
+
+    uint8_t SPIFlash::read_status()
+    {
+        select();
+        m_spi.transfer(SPICommand::STATUSREAD);
+        uint8_t status = m_spi.transfer(0);
+        unselect();
+        return status;
+    }
+
+    void SPIFlash::write(uint32_t addr, uint8_t bt)
+    {
+        command(SPICommand::BYTEPAGEPROGRAM, true);
+        m_spi.transfer(addr >> 16);
+        m_spi.transfer(addr >> 8);
+        m_spi.transfer(addr);
+        m_spi.transfer(bt);
+        unselect();
+    }
+
+    void SPIFlash::write_array(uint32_t addr, const void* buf, uint16_t len)
+    {
+        uint16_t bytes_in_page = SPIFLASH_PAGESIZE - (addr % SPIFLASH_PAGESIZE);
+        uint16_t offset = 0;
+
+        while (len > 0)
+        {
+            uint16_t batch_size = (len <= bytes_in_page) ? len : bytes_in_page;
+
+            command(SPICommand::BYTEPAGEPROGRAM, true);
+            m_spi.transfer(addr >> 16);
+            m_spi.transfer(addr >> 8);
+            m_spi.transfer(addr);
+
+            for (uint16_t i = 0; i < batch_size; i++)
+            {
+                m_spi.transfer(((uint8_t*)buf)[offset + i]);
+            }
+
+            unselect();
+
+            //wait till it's programmed
+            while(write_enable_latch());
+
+            addr += batch_size;
+            offset += batch_size;
+            len -= batch_size;
+            bytes_in_page = SPIFLASH_PAGESIZE;
+        }
+    }
+
+    void SPIFlash::write_array_dma(uint32_t addr, const void* buf, uint16_t len)
+    {
+        const uint8_t * byte_buf = (const uint8_t*)buf;
+        uint16_t bytes_in_page = SPIFLASH_PAGESIZE - (addr % SPIFLASH_PAGESIZE);
+
+        while (len > 0)
+        {
+            uint16_t batch_size = (len <= bytes_in_page) ? len : bytes_in_page;
+
+            command(SPICommand::BYTEPAGEPROGRAM, true);
+            m_spi.transfer(addr >> 16);
+            m_spi.transfer(addr >> 8);
+            m_spi.transfer(addr);
+
+            m_spi.dmaSend(byte_buf, batch_size);
+
+            unselect();
+
+            //wait till it's programmed
+            while(write_enable_latch());
+
+            addr += batch_size;
+            byte_buf += batch_size;
+            len -= batch_size;
+            bytes_in_page = SPIFLASH_PAGESIZE;
+        }
+    }
+
+    void SPIFlash::erase_full_chip()
+    {
+        command(SPICommand::CHIPERASE, true);
+        unselect();
+        while(write_enable_latch());
+    }
+
+    void SPIFlash::erase_4K(uint32_t addr)
+    {
+        command(SPICommand::BLOCKERASE_4K, true);
+        m_spi.transfer(addr >> 16);
+        m_spi.transfer(addr >> 8);
+        m_spi.transfer(addr);
+        unselect();
+        while(write_enable_latch());
+    }
+
+    void SPIFlash::erase_32K(uint32_t addr)
+    {
+        command(SPICommand::BLOCKERASE_32K, true);
+        m_spi.transfer(addr >> 16);
+        m_spi.transfer(addr >> 8);
+        m_spi.transfer(addr);
+        unselect();
+        while(write_enable_latch());
+    }
+
+    void SPIFlash::erase_64K(uint32_t addr)
+    {
+        command(SPICommand::BLOCKERASE_64K, true);
+        m_spi.transfer(addr >> 16);
+        m_spi.transfer(addr >> 8);
+        m_spi.transfer(addr);
+        unselect();
+        while(write_enable_latch());
+    }
+
+    void SPIFlash::sleep()
+    {
+        command(SPICommand::SLEEP);
+        unselect();
+    }
+
+    void SPIFlash::wakeup()
+    {
+        command(SPICommand::WAKE);
+        unselect();
+    }
+
+    void SPIFlash::end()
+    {
+        m_spi.end();
+    }
+}