Subversion Repositories neorv32

// #################################################################################################

// # << NEORV32 - SPI Bus Explorer Demo Program >>                                                 #

// # ********************************************************************************************* #

// # BSD 3-Clause License                                                                          #

// #                                                                                               #

// # Copyright (c) 2021, Stephan Nolting. All rights reserved.                                     #

// #                                                                                               #

// # Redistribution and use in source and binary forms, with or without modification, are          #

// # permitted provided that the following conditions are met:                                     #

// #                                                                                               #

// # 1. Redistributions of source code must retain the above copyright notice, this list of        #

// #    conditions and the following disclaimer.                                                   #

// #                                                                                               #

// # 2. Redistributions in binary form must reproduce the above copyright notice, this list of     #

// #    conditions and the following disclaimer in the documentation and/or other materials        #

// #    provided with the distribution.                                                            #

// #                                                                                               #

// # 3. Neither the name of the copyright holder nor the names of its contributors may be used to  #

// #    endorse or promote products derived from this software without specific prior written      #

// #    permission.                                                                                #

// #                                                                                               #

// # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS   #

// # OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF               #

// # MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE    #

// # COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,     #

// # EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE #

// # GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED    #

// # AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING     #

// # NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED  #

// # OF THE POSSIBILITY OF SUCH DAMAGE.                                                            #

// # ********************************************************************************************* #

// # The NEORV32 Processor - https://github.com/stnolting/neorv32              (c) Stephan Nolting #

// #################################################################################################

/**********************************************************************//**

 * @file demo_spi/main.c

 * @author Stephan Nolting

 * @brief SPI bus explorer (execute SPI transactions by hand).

 **************************************************************************/

#include <neorv32.h>

#include <string.h>

/**********************************************************************//**

 * @name User configuration

 **************************************************************************/

/**@{*/

/** UART BAUD rate */

#define BAUD_RATE 19200

/**@}*/

// Global variables

uint32_t spi_configured;

uint32_t spi_size; // data quantity in bytes

// Prototypes

void spi_cs(uint32_t type);

void spi_trans(void);

void spi_setup(void);

void flash_write(void);

void flash_read(void);

uint32_t hexstr_to_uint(char *buffer, uint8_t length);

void aux_print_hex_byte(uint8_t byte);

/**********************************************************************//**

 * SPI flash commands

 **************************************************************************/

enum SPI_FLASH_CMD {

  SPI_FLASH_CMD_WRITE    = 0x02, /**< Write data */

  SPI_FLASH_CMD_READ     = 0x03, /**< Read data */

  SPI_FLASH_CMD_READ_SR  = 0x05, /**< Get status register */

  SPI_FLASH_CMD_WREN     = 0x06  /**< Enable write access */

};

/**********************************************************************//**

 * This program provides an interactive console to communicate with SPI devices.

 *

 * @note This program requires the UART and the SPI to be synthesized.

 *

 * @return Irrelevant.

 **************************************************************************/

int main() {

  char buffer[16];

  int length = 0;

  // capture all exceptions and give debug info via UART

  // this is not required, but keeps us safe

  neorv32_rte_setup();

  // init UART0 at default baud rate, no parity bits, ho hw flow control

  neorv32_uart0_setup(BAUD_RATE, PARITY_NONE, FLOW_CONTROL_NONE);

  // check if UART0 unit is implemented at all

  if (neorv32_uart0_available() == 0) {

    return 1;

  }

  // intro

  neorv32_uart0_printf("\n<<< SPI Bus Explorer >>>\n\n");

  // check if SPI unit is implemented at all

  if (neorv32_spi_available() == 0) {

    neorv32_uart0_printf("No SPI unit implemented.");

    return 1;

  }

  // info

  neorv32_uart0_printf("This program allows to create SPI transfers by hand.\n"

                      "Type 'help' to see the help menu.\n\n");

  // disable and reset SPI module

  NEORV32_SPI.CTRL = 0;

  spi_configured = 0; // SPI not configured yet

  spi_size = 0;

  // Main menu

  for (;;) {

    neorv32_uart0_printf("SPI_EXPLORER:> ");

    length = neorv32_uart0_scan(buffer, 15, 1);

    neorv32_uart0_printf("\n");

    if (!length) // nothing to be done

     continue;

    // decode input and execute command

    if (!strcmp(buffer, "help")) {

      neorv32_uart0_printf("Available commands:\n"

                          " help     - show this text\n"

                          " setup    - configure SPI module (clock speed and mode, data size)\n"

                          " cs-en    - enable CS line (set low)\n"

                          " cs-dis   - disable CS line (set high)\n"

                          " trans    - execute a transmission (write & read to/from SPI)\n"

                          "\n"

                          " flash-wr - write binary file to SPI flash\n"

                          " flash-rd - dump SPI flash\n"

                          "\n"

                          "Configure the SPI module using 'setup'. Enable a certain module using 'cs-en',\n"

                          "then transfer data using 'trans' and disable the module again using 'cs-dis'.\n"

                          "\n"

                          "Standard SPI flash and EEPROM memories can be programmed/read\n"

                          "via 'flash-wr' and 'flash-rd'.\n\n");

    }

    else if (!strcmp(buffer, "setup")) {

      spi_setup();

    }

    else if (!strcmp(buffer, "cs-en")) {

      spi_cs(1);

    }

    else if (!strcmp(buffer, "cs-dis")) {

      spi_cs(0);

    }

    else if (!strcmp(buffer, "trans")) {

      spi_trans();

    }

    else if (!strcmp(buffer, "flash-wr")) {

      flash_write();

    }

    else if (!strcmp(buffer, "flash-rd")) {

      flash_read();

    }

    else {

      neorv32_uart0_printf("Invalid command. Type 'help' to see all commands.\n");

    }

  }

  return 0;

}

/**********************************************************************//**

 * Enable or disable chip-select line

 *

 * @param[in] type 0=disable, 1=enable

 **************************************************************************/

void spi_cs(uint32_t type) {

  char terminal_buffer[2];

  uint8_t channel;

  if (type) {

    neorv32_uart0_printf("Select chip-select line to enable (set low) [0..7]: ");

  }

  else {

    neorv32_uart0_printf("Select chip-select line to disable (set high) [0..7]: ");

  }

  while (1) {

    neorv32_uart0_scan(terminal_buffer, 2, 1); // 1 hex char plus '\0'

    channel = (uint8_t)hexstr_to_uint(terminal_buffer, strlen(terminal_buffer));

    if (channel > 7) {

      neorv32_uart0_printf("\nInvalid channel selection!\n");

      return;

    }

    else {

      neorv32_uart0_printf("\n");

      break;

    }

  }

  if (type) {

    neorv32_spi_cs_en(channel);

  }

  else {

    neorv32_spi_cs_dis(channel);

  }

}

/**********************************************************************//**

 * SPI data transfer

 **************************************************************************/

void spi_trans(void) {

  char terminal_buffer[9];

  if (spi_configured == 0) {

    neorv32_uart0_printf("SPI module not configured yet! Use 'setup' to configure SPI module.\n");

    return;

  }

  neorv32_uart0_printf("Enter TX data (%u hex chars): 0x", spi_size*2);

  neorv32_uart0_scan(terminal_buffer, spi_size*2+1, 1);

  uint32_t tx_data = (uint32_t)hexstr_to_uint(terminal_buffer, strlen(terminal_buffer));

  uint32_t rx_data = neorv32_spi_trans(tx_data);

  if (spi_size == 1) {

    neorv32_uart0_printf("\nTX data: 0x");

    aux_print_hex_byte((uint8_t)(tx_data));

    neorv32_uart0_printf("\nRX data: 0x");

    aux_print_hex_byte((uint8_t)(rx_data));

    neorv32_uart0_printf("\n");

  }

  else if (spi_size == 2) {

    neorv32_uart0_printf("\nTX data: 0x");

    aux_print_hex_byte((uint8_t)(tx_data >> 8));

    aux_print_hex_byte((uint8_t)(tx_data));

    neorv32_uart0_printf("\nRX data: 0x");

    aux_print_hex_byte((uint8_t)(rx_data >> 8));

    aux_print_hex_byte((uint8_t)(rx_data));

    neorv32_uart0_printf("\n");

  }

  else if (spi_size == 3) {

    neorv32_uart0_printf("\nTX data: 0x");

    aux_print_hex_byte((uint8_t)(tx_data >> 16));

    aux_print_hex_byte((uint8_t)(tx_data >> 8));

    aux_print_hex_byte((uint8_t)(tx_data));

    neorv32_uart0_printf("\nRX data: 0x");

    aux_print_hex_byte((uint8_t)(rx_data >> 16));

    aux_print_hex_byte((uint8_t)(rx_data >> 8));

    aux_print_hex_byte((uint8_t)(rx_data));

    neorv32_uart0_printf("\n");

  }

  else {

    neorv32_uart0_printf("\nTX data: 0x%x\n", tx_data);

    neorv32_uart0_printf("RX data: 0x%x\n", rx_data);

  }

}

/**********************************************************************//**

 * Configure SPI module

 **************************************************************************/

void spi_setup(void) {

  char terminal_buffer[9];

  uint8_t spi_prsc, clk_phase, clk_pol, data_size;

  uint32_t tmp;

  // ---- SPI clock ----

  while (1) {

  neorv32_uart0_printf("Select SPI clock prescaler (0..7): ");

  neorv32_uart0_scan(terminal_buffer, 2, 1);

  tmp = (uint32_t)hexstr_to_uint(terminal_buffer, strlen(terminal_buffer));

    if (tmp > 8) {

      neorv32_uart0_printf("\nInvalid selection!\n");

    }

    else {

      spi_prsc = (uint8_t)tmp;

      break;

    }

  }

  uint32_t div = 0;

  switch (spi_prsc) {

    case 0: div = 2 * 2; break;

    case 1: div = 2 * 4; break;

    case 2: div = 2 * 8; break;

    case 3: div = 2 * 64; break;

    case 4: div = 2 * 128; break;

    case 5: div = 2 * 1024; break;

    case 6: div = 2 * 2048; break;

    case 7: div = 2 * 4096; break;

    default: div = 0; break;

  }

  uint32_t clock = NEORV32_SYSINFO.CLK / div;

  neorv32_uart0_printf("\n+ New SPI clock speed = %u Hz\n", clock);

  // ---- SPI clock mode ----

  while (1) {

  neorv32_uart0_printf("Select SPI clock mode (0..3): ");

  neorv32_uart0_scan(terminal_buffer, 2, 1);

  tmp = (uint32_t)hexstr_to_uint(terminal_buffer, strlen(terminal_buffer));

    if (tmp > 4) {

      neorv32_uart0_printf("\nInvalid selection!\n");

    }

    else {

      clk_pol   = (uint8_t)((tmp >> 1) & 1);

      clk_phase = (uint8_t)(tmp & 1);

      break;

    }

  }

  neorv32_uart0_printf("\n+ New SPI clock mode = %u\n", tmp);

  // ---- SPI transfer data quantity ----

  while (1) {

  neorv32_uart0_printf("Select SPI data transfer size in bytes (1,2,3,4): ");

  neorv32_uart0_scan(terminal_buffer, 2, 1);

  tmp = (uint32_t)hexstr_to_uint(terminal_buffer, strlen(terminal_buffer));

    if ( (tmp < 1) || (tmp > 4)) {

      neorv32_uart0_printf("\nInvalid selection!\n");

    }

    else {

      data_size = (uint8_t)(tmp - 1);

      break;

    }

  }

  neorv32_uart0_printf("\n+ New SPI data size = %u-byte(s)\n\n", tmp);

  neorv32_spi_setup(spi_prsc, clk_phase, clk_pol, data_size);

  spi_configured = 1; // SPI is configured now

  spi_size = tmp;

}

/**********************************************************************//**

 * Read (dump) flash

 **************************************************************************/

void flash_read(void) {

  char terminal_buffer[9];

  uint32_t tmp, addr, channel, num_addr_bytes;

  if (spi_configured == 0) {

    neorv32_uart0_printf("SPI module not configured yet! Use 'setup' to configure SPI module.\n");

    return;

  }

  // configure 8-bit SPI mode

  tmp = NEORV32_SPI.CTRL;

  tmp &= ~(0x03 << SPI_CTRL_SIZE0);

  NEORV32_SPI.CTRL = tmp;

  neorv32_uart0_printf("Warning! SPI size configuration has been overridden!\n");

  // how many address bytes?

  while (1) {

    neorv32_uart0_printf("Enter number of address bytes (2,3): ");

    neorv32_uart0_scan(terminal_buffer, 2, 1); // 1 hex char plus '\0'

    num_addr_bytes = hexstr_to_uint(terminal_buffer, strlen(terminal_buffer));

    if ((num_addr_bytes < 2) || (num_addr_bytes > 3)) {

      neorv32_uart0_printf("\nInvalid channel selection!\n");

      continue;

    }

    else {

      break;

    }

  }

  // chip-select

  while (1) {

    neorv32_uart0_printf("\nSelect flash chip-select line [0..7]: ");

    neorv32_uart0_scan(terminal_buffer, 2, 1); // 1 hex char plus '\0'

    channel = hexstr_to_uint(terminal_buffer, strlen(terminal_buffer));

    if (channel > 7) {

      neorv32_uart0_printf("\nInvalid channel selection!\n");

      continue;

    }

    else {

      break;

    }

  }

  // base address

  neorv32_uart0_printf("\nEnter base address (8 hex chars): 0x");

  neorv32_uart0_scan(terminal_buffer, 9, 1);

  addr = (uint32_t)hexstr_to_uint(terminal_buffer, strlen(terminal_buffer));

  neorv32_uart0_printf("\nPress any key to start. Press any key to stop reading.\n");

  while(neorv32_uart0_char_received() == 0);

  while(1) {

    if (neorv32_uart0_char_received()) { // abort when key pressed

      break;

    }

    if ((addr & 0x1f) == 0) {

      neorv32_uart0_printf("\n%x: ", addr);

    }

    // read byte

    neorv32_spi_cs_en((uint8_t)channel);

    neorv32_spi_trans(SPI_FLASH_CMD_READ);

    if (num_addr_bytes == 3) {

      neorv32_spi_trans(addr >> 16);

    }

    neorv32_spi_trans(addr >> 8);

    neorv32_spi_trans(addr >> 0);

    tmp = neorv32_spi_trans(0);

    neorv32_spi_cs_dis((uint8_t)channel);

    aux_print_hex_byte((uint8_t)tmp);

    neorv32_uart0_putc(' ');

    addr++;

  }

  neorv32_uart0_printf("\n");

  spi_configured = 0;

}

/**********************************************************************//**

 * Write flash

 **************************************************************************/

void flash_write(void) {

  neorv32_uart0_printf("work-in-progress\n");

  return;

  char terminal_buffer[9], rx_data;

  uint32_t tmp, addr, channel, num_data_bytes, num_addr_bytes;

  int res;

  if (spi_configured == 0) {

    neorv32_uart0_printf("SPI module not configured yet! Use 'setup' to configure SPI module.\n");

    return;

  }

  // configure 8-bit SPI mode

  tmp = NEORV32_SPI.CTRL;

  tmp &= ~(0x03 << SPI_CTRL_SIZE0);

  NEORV32_SPI.CTRL = tmp;

  neorv32_uart0_printf("Warning! SPI size configuration has been overridden!\n");

  // how many address bytes?

  while (1) {

    neorv32_uart0_printf("Enter number of address bytes (2,3): ");

    neorv32_uart0_scan(terminal_buffer, 2, 1); // 1 hex char plus '\0'

    num_addr_bytes = hexstr_to_uint(terminal_buffer, strlen(terminal_buffer));

    if ((num_addr_bytes < 2) || (num_addr_bytes > 3)) {

      neorv32_uart0_printf("\nInvalid channel selection!\n");

      continue;

    }

    else {

      break;

    }

  }

  // how many bytes?

  neorv32_uart0_printf("\nEnter total number of bytes to write (%u hex chars): ", num_addr_bytes*2);

  neorv32_uart0_scan(terminal_buffer, num_addr_bytes*2+1, 1); // 1 hex char plus '\0'

  num_data_bytes = hexstr_to_uint(terminal_buffer, strlen(terminal_buffer));

  // chip-select

  while (1) {

    neorv32_uart0_printf("\nSelect flash chip-select line [0..7]: ");

    neorv32_uart0_scan(terminal_buffer, 2, 1); // 1 hex char plus '\0'

    channel = hexstr_to_uint(terminal_buffer, strlen(terminal_buffer));

    if (channel > 7) {

      neorv32_uart0_printf("\nInvalid channel selection!\n");

      continue;

    }

    else {

      break;

    }

  }

  // base address

  neorv32_uart0_printf("\nEnter base address (8 hex chars): 0x");

  neorv32_uart0_scan(terminal_buffer, 9, 1);

  addr = (uint32_t)hexstr_to_uint(terminal_buffer, strlen(terminal_buffer));

  // start!

  neorv32_uart0_printf("\nSend raw data via UART (%u bytes)...\n", num_data_bytes);

  while (neorv32_uart0_tx_busy());

  // clear UART0 FIFOs

  neorv32_uart0_disable();

  neorv32_uart0_enable();

  while (num_data_bytes) {

    // write enable

    neorv32_spi_cs_en((uint8_t)channel);

    neorv32_spi_trans(SPI_FLASH_CMD_WREN);

    neorv32_spi_cs_dis((uint8_t)channel);

    // get new UART data

    while(1) {

      res = neorv32_uart0_getc_safe(&rx_data);

      if (res == -1) {

        continue;

      }

      if (res == 0) {

        break;

      }

      else {

        neorv32_uart0_printf("UART transmission error (%i)!\n", res);

        return;

      }

    }

    // write byte

    neorv32_spi_cs_en((uint8_t)channel);

    neorv32_spi_trans(SPI_FLASH_CMD_WRITE);

    if (num_addr_bytes == 3) {

      neorv32_spi_trans(addr >> 16);

    }

    neorv32_spi_trans(addr >> 8);

    neorv32_spi_trans(addr >> 0);

    neorv32_spi_trans((uint32_t)rx_data);

    neorv32_spi_cs_dis((uint8_t)channel);

    // check status register

    while (1) {

      neorv32_spi_cs_en((uint8_t)channel);

      neorv32_spi_trans(SPI_FLASH_CMD_READ_SR);

      tmp = neorv32_spi_trans(0);

      neorv32_spi_cs_dis((uint8_t)channel);

      if ((tmp & 0x01) == 0) { // write-in-progress flag cleared?

        break;

      }

    }

    addr++;

    num_data_bytes--;

  }

  neorv32_uart0_printf("\n");

  spi_configured = 0;

}

/**********************************************************************//**

 * Helper function to convert N hex chars string into uint32_T

 *

 * @param[in,out] buffer Pointer to array of chars to convert into number.

 * @param[in,out] length Length of the conversion string.

 * @return Converted number.

 **************************************************************************/

uint32_t hexstr_to_uint(char *buffer, uint8_t length) {

  uint32_t res = 0, d = 0;

  char c = 0;

  while (length--) {

    c = *buffer++;

    if ((c >= '0') && (c <= '9'))

      d = (uint32_t)(c - '0');

    else if ((c >= 'a') && (c <= 'f'))

      d = (uint32_t)((c - 'a') + 10);

    else if ((c >= 'A') && (c <= 'F'))

      d = (uint32_t)((c - 'A') + 10);

    else

      d = 0;

    res = res + (d << (length*4));

  }

  return res;

}

/**********************************************************************//**

 * Print HEX byte.

 *

 * @param[in] byte Byte to be printed as 2-cahr hex value.

 **************************************************************************/

void aux_print_hex_byte(uint8_t byte) {

  static const char symbols[] = "0123456789abcdef";

  neorv32_uart0_putc(symbols[(byte >> 4) & 0x0f]);

  neorv32_uart0_putc(symbols[(byte >> 0) & 0x0f]);

}