text: /* 
   * The MIT License (MIT)
   *
   * Copyright (c) 2018, hathach (tinyusb.org)
   * Copyright (c) 2020, Koji Kitayama
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy
   * of this software and associated documentation files (the "Software"), to deal
   * in the Software without restriction, including without limitation the rights
   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   * copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in
   * all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   * THE SOFTWARE.
   *
   * This file is part of the TinyUSB stack.
   */
  
  #include "../board.h"
  #include "fsl_device_registers.h"
  #include "fsl_gpio.h"
  #include "fsl_port.h"
  #include "fsl_clock.h"
  #include "fsl_lpsci.h"
  
  #include "clock_config.h"
  
  //--------------------------------------------------------------------+
  // Forward USB interrupt events to TinyUSB IRQ Handler
  //--------------------------------------------------------------------+
  void USB0_IRQHandler(void)
  {
    tud_int_handler(0);
  }
  
  //--------------------------------------------------------------------+
  // MACRO TYPEDEF CONSTANT ENUM DECLARATION
  //--------------------------------------------------------------------+
  // LED
  #define LED_PINMUX            IOMUXC_GPIO_AD_B0_09_GPIO1_IO09
  #define LED_PORT              GPIOB
  #define LED_PIN_CLOCK         kCLOCK_PortB
  #define LED_PIN_PORT          PORTB
  #define LED_PIN               19U
  #define LED_PIN_FUNCTION      kPORT_MuxAsGpio
  #define LED_STATE_ON          0
  
  // Button
  #define BUTTON_PORT           GPIOC
  #define BUTTON_PIN_CLOCK      kCLOCK_PortC
  #define BUTTON_PIN_PORT       PORTC
  #define BUTTON_PIN            9U
  #define BUTTON_PIN_FUNCTION   kPORT_MuxAsGpio
  #define BUTTON_STATE_ACTIVE   0
  
  // UART
  #define UART_PORT             UART0
  #define UART_PIN_CLOCK        kCLOCK_PortA
  #define UART_PIN_PORT         PORTA
  #define UART_PIN_RX           1u
  #define UART_PIN_TX           2u
  #define UART_PIN_FUNCTION     kPORT_MuxAlt2
  #define SOPT5_UART0RXSRC_UART_RX      0x00u   /*!< UART0 receive data source select: UART0_RX pin */
  #define SOPT5_UART0TXSRC_UART_TX      0x00u   /*!< UART0 transmit data source select: UART0_TX pin */
  
  const uint8_t dcd_data[] = { 0x00 };
  
  void board_init(void)
  {
    BOARD_BootClockRUN();
    SystemCoreClockUpdate();
  
  #if CFG_TUSB_OS == OPT_OS_NONE
    // 1ms tick timer
    SysTick_Config(SystemCoreClock / 1000);
  #elif CFG_TUSB_OS == OPT_OS_FREERTOS
    // If freeRTOS is used, IRQ priority is limit by max syscall ( smaller is higher )
    NVIC_SetPriority(USB0_IRQn, configLIBRARY_MAX_SYSCALL_INTERRUPT_PRIORITY );
  #endif
  
    // LED
    CLOCK_EnableClock(LED_PIN_CLOCK);
    PORT_SetPinMux(LED_PIN_PORT, LED_PIN, LED_PIN_FUNCTION);
    gpio_pin_config_t led_config = { kGPIO_DigitalOutput, 0 };
    GPIO_PinInit(LED_PORT, LED_PIN, &led_config);
    board_led_write(false);
  
  #if defined(BUTTON_PORT) && defined(BUTTON_PIN)
    // Button
    CLOCK_EnableClock(BUTTON_PIN_CLOCK);
    port_pin_config_t button_port = {
      .pullSelect = kPORT_PullUp, 
      .mux = BUTTON_PIN_FUNCTION,
    };
    PORT_SetPinConfig(BUTTON_PIN_PORT, BUTTON_PIN, &button_port);
    gpio_pin_config_t button_config = { kGPIO_DigitalInput, 0 };
    GPIO_PinInit(BUTTON_PORT, BUTTON_PIN, &button_config);
  #endif
  
    // UART
    CLOCK_EnableClock(UART_PIN_CLOCK);
    PORT_SetPinMux(UART_PIN_PORT, UART_PIN_RX, UART_PIN_FUNCTION);
    PORT_SetPinMux(UART_PIN_PORT, UART_PIN_TX, UART_PIN_FUNCTION);
    SIM->SOPT5 = ((SIM->SOPT5 &
      (~(SIM_SOPT5_UART0TXSRC_MASK | SIM_SOPT5_UART0RXSRC_MASK)))
        | SIM_SOPT5_UART0TXSRC(SOPT5_UART0TXSRC_UART_TX)
        | SIM_SOPT5_UART0RXSRC(SOPT5_UART0RXSRC_UART_RX)
      );
  
    lpsci_config_t uart_config;
    CLOCK_SetLpsci0Clock(1);
    LPSCI_GetDefaultConfig(&uart_config);
    uart_config.baudRate_Bps = CFG_BOARD_UART_BAUDRATE;
    uart_config.enableTx = true;
    uart_config.enableRx = true;
    LPSCI_Init(UART_PORT, &uart_config, CLOCK_GetPllFllSelClkFreq());
  
    // USB
    CLOCK_EnableUsbfs0Clock(kCLOCK_UsbSrcPll0, CLOCK_GetFreq(kCLOCK_PllFllSelClk));
  }
  
  //--------------------------------------------------------------------+
  // Board porting API
  //--------------------------------------------------------------------+
  
  void board_led_write(bool state)
  {
    GPIO_WritePinOutput(LED_PORT, LED_PIN, state ? LED_STATE_ON : (1-LED_STATE_ON));
  }
  
  uint32_t board_button_read(void)
  {
  #if defined(BUTTON_PORT) && defined(BUTTON_PIN)
    return BUTTON_STATE_ACTIVE == GPIO_ReadPinInput(BUTTON_PORT, BUTTON_PIN);
  #endif
    return 0;
  }
  
  int board_uart_read(uint8_t* buf, int len)
  {
    LPSCI_ReadBlocking(UART_PORT, buf, len);
    return len;
  }
  
  int board_uart_write(void const * buf, int len)
  {
    LPSCI_WriteBlocking(UART_PORT, (uint8_t*)buf, len);
    return len;
  }
  
  #if CFG_TUSB_OS == OPT_OS_NONE
  volatile uint32_t system_ticks = 0;
  void SysTick_Handler(void)
  {
    system_ticks++;
  }
  
  uint32_t board_millis(void)
  {
    return system_ticks;
  }
  #endif
  