/******************************************************************************
 * @file     main.c
 * @version  V3.00
 * @brief
 *           Demonstrate how to implement a USB mass storage.
 *           It uses embedded Data Flash as storage.
 *
 * @copyright SPDX-License-Identifier: Apache-2.0
 * @copyright Copyright (C) 2021 Nuvoton Technology Corp. All rights reserved.
 ******************************************************************************/
#include <stdio.h>
#include "NuMicro.h"
#include "massstorage.h"

/* If crystal-less is enabled, system won't use any crystal as clock source
   If using crystal-less, system will be 48MHz, otherwise, system is 72MHz
*/
#define CRYSTAL_LESS        1
#define HIRC_AUTO_TRIM      0x611   /* Use USB signal to fine tune HIRC 48MHz */
#define TRIM_INIT           (SYS_BASE+0x110)

#define CONFIG_BASE      0x00300000
#define DATA_FLASH_BASE  MASS_STORAGE_OFFSET

/*--------------------------------------------------------------------------*/
void SYS_Init(void)
{
    /*---------------------------------------------------------------------------------------------------------*/
    /* Init System Clock                                                                                       */
    /*---------------------------------------------------------------------------------------------------------*/
    /* Enable HIRC clock */
    CLK_EnableXtalRC(CLK_PWRCTL_HIRCEN_Msk);

    /* Wait for HIRC clock ready */
    CLK_WaitClockReady(CLK_STATUS_HIRCSTB_Msk);

#if (!CRYSTAL_LESS)
    /* Enable HXT clock */
    CLK_EnableXtalRC(CLK_PWRCTL_HXTEN_Msk);

    /* Wait for HXT clock ready */
    CLK_WaitClockReady(CLK_STATUS_HXTSTB_Msk);

    /* Set core clock to 72MHz */
    CLK_SetCoreClock(72000000);

    /* Select USB clock source as PLL and USB clock divider as 3 */
    CLK_SetModuleClock(USBD_MODULE, CLK_CLKSEL3_USBDSEL_PLL, CLK_CLKDIV0_USB(3));
#else
    /* Select HCLK clock source to HIRC and HCLK clock divider as 1 */
    CLK_SetHCLK(CLK_CLKSEL0_HCLKSEL_HIRC, CLK_CLKDIV0_HCLK(1));

    /* Select USB clock source as HIRC and USB clock divider as 1 */
    CLK_SetModuleClock(USBD_MODULE, CLK_CLKSEL3_USBDSEL_HIRC, CLK_CLKDIV0_USB(1));
#endif

    /* Enable UART0 module clock */
    CLK_EnableModuleClock(UART0_MODULE);

    /* Select UART0 module clock source as HIRC/2 and UART0 module clock divider as 1 */
    CLK_SetModuleClock(UART0_MODULE, CLK_CLKSEL1_UART0SEL_HIRC_DIV2, CLK_CLKDIV0_UART0(1));

    /* Enable USBD module clock */
    CLK_EnableModuleClock(USBD_MODULE);

    /*---------------------------------------------------------------------------------------------------------*/
    /* Init I/O Multi-function                                                                                 */
    /*---------------------------------------------------------------------------------------------------------*/
    /* Set PB multi-function pins for UART0 RXD and TXD */
    SYS->GPB_MFPH = (SYS->GPB_MFPH & (~(UART0_RXD_PB12_Msk | UART0_TXD_PB13_Msk))) | UART0_RXD_PB12 | UART0_TXD_PB13;
}


void UART0_Init(void)
{
    /*---------------------------------------------------------------------------------------------------------*/
    /* Init UART                                                                                               */
    /*---------------------------------------------------------------------------------------------------------*/
    /* Reset IP */
    SYS->IPRST1 |=  SYS_IPRST1_UART0RST_Msk;
    SYS->IPRST1 &= ~SYS_IPRST1_UART0RST_Msk;

    /* Configure UART0 and set UART0 Baudrate */
    UART0->BAUD = UART_BAUD_MODE2 | UART_BAUD_MODE2_DIVIDER((__HIRC >> 1), 115200);
    UART0->LINE = UART_WORD_LEN_8 | UART_PARITY_NONE | UART_STOP_BIT_1;
}


/*---------------------------------------------------------------------------------------------------------*/
/*  Main Function                                                                                          */
/*---------------------------------------------------------------------------------------------------------*/
int32_t main(void)
{
    uint32_t au32Config[2];
#if CRYSTAL_LESS
    uint32_t u32TrimInit;
#endif
    
    /* Unlock protected registers */
    SYS_UnlockReg();

    /* Init system and multi-function I/O */
    SYS_Init();

    /* Init UART for debug message */
    UART0_Init();

    printf("+-------------------------------------------------------+\n");
    printf("|          NuMicro USB MassStorage Sample Code          |\n");
    printf("+-------------------------------------------------------+\n");

    /* Enable FMC ISP function */
    FMC_Open();

    /* Read User Configuration */
    FMC_ReadConfig(au32Config, 2);

    /* Check if Data Flash Size is 36K. If not, to re-define Data Flash size and to enable Data Flash function */
    if(((au32Config[0] & 0x01) == 1) || ((au32Config[0] & 0x04) == 0x4) || (au32Config[1] != DATA_FLASH_BASE))
    {
        FMC_EnableConfigUpdate();
        au32Config[0] &= ~0x5;
        au32Config[1] = DATA_FLASH_BASE;
        if(FMC_WriteConfig(au32Config, 2) < 0)
        {
            printf("Error! Fail to write User Configuration.\n");
            /* Disable FMC ISP function */
            FMC_Close();
            return -1;
        }

        FMC_ReadConfig(au32Config, 2);
        if(((au32Config[0] & 0x01) == 1) || ((au32Config[0] & 0x04) == 0x4) || (au32Config[1] != DATA_FLASH_BASE))
        {
            printf("Error! Fail to write User Configuration.\n");
            /* Disable FMC ISP function */
            FMC_Close();
            return -1;
        }

        /* Reset Chip to reload new CONFIG value */
        SYS->IPRST0 = SYS_IPRST0_CHIPRST_Msk;
    }

    printf("cfg0=%08x cfg1=%08x\n", au32Config[0], au32Config[1]);

    printf("NuMicro USB MassStorage Start!\n");

    /* Open USB controller */
    USBD_Open(&gsInfo, MSC_ClassRequest, NULL);

    USBD_SetConfigCallback(MSC_SetConfig);

    /* Endpoint configuration */
    MSC_Init();

    /* Start USB device */
    USBD_Start();

    /* Enable USB device interrupt */
    NVIC_EnableIRQ(USBD_IRQn);

#if CRYSTAL_LESS
    /* Backup default trim */
    u32TrimInit = M32(TRIM_INIT);
#endif

    /* Clear SOF */
    USBD->INTSTS = USBD_INTSTS_SOFIF_Msk;

    while(1)
    {
#if CRYSTAL_LESS
        /* Start USB trim if it is not enabled. */
        if((SYS->IRCTCTL & SYS_IRCTCTL_FREQSEL_Msk) != 1)
        {
            /* Start USB trim only when SOF */
            if(USBD->INTSTS & USBD_INTSTS_SOFIF_Msk)
            {
                /* Clear SOF */
                USBD->INTSTS = USBD_INTSTS_SOFIF_Msk;

                /* Re-enable crystal-less */
                SYS->IRCTCTL = HIRC_AUTO_TRIM | (8 << SYS_IRCTCTL_BOUNDARY_Pos);
            }
        }

        /* Disable USB Trim when error */
        if(SYS->IRCTISTS & (SYS_IRCTISTS_CLKERRIF_Msk | SYS_IRCTISTS_TFAILIF_Msk))
        {
            /* Init TRIM */
            M32(TRIM_INIT) = u32TrimInit;

            /* Disable crystal-less */
            SYS->IRCTCTL = 0;

            /* Clear error flags */
            SYS->IRCTISTS = SYS_IRCTISTS_CLKERRIF_Msk | SYS_IRCTISTS_TFAILIF_Msk;

            /* Clear SOF */
            USBD->INTSTS = USBD_INTSTS_SOFIF_Msk;
        }
#endif

        MSC_ProcessCmd();
    }
}
