/******************************************************************************
 * @file     main.c
 * @version  V3.00
 * @brief    Demonstrate how to simulate a USB CD-ROM device.
 * @note
 *
 *           This sample simulate a USB CD-ROM with a test.txt file.
 *           User can change file within CD-ROM, follow steps below:
 *
 *           (1) Generate an ISO file via ISO Workshop.
 *               http://www.glorylogic.com/iso-workshop/
 *               -> Option : Select ISO9660 Level1
 *
 *           (2) Convert the .iso file into C code file via SRecord tool
 *               http://srecord.sourceforge.net
 *
 *               -> srec_cat InputFile.iso -binary -o OutputFile.c -C-Array
 *
 *           (3) The System Area, the first 32768 data bytes is unused by ISO 9660.
 *               Therefore, user need to delete the first 32768 bytes on the DiskImg.c
 *               manually to save space. Finally, replace DiskImg.c in this project.
 *
 *               -> EPROM_LENGTH in DiskImg.c is the size of your .iso image.
 *                  Define MSC_ImageSize value in massstorage.h in this project.
 *                  Modify MSC_ImageSize value to hold the file size.
 *
 * @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

int IsDebugFifoEmpty(void);

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 GPIO Port F module clock */
    CLK_EnableModuleClock(GPIOF_MODULE);

    /* Set XT1_OUT(PF.2) and XT1_IN(PF.3) as input mode to use HXT */
    GPIO_SetMode(PF, BIT2|BIT3, GPIO_MODE_INPUT);

    /* 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;
}

void PowerDown()
{
    /* Unlock protected registers */
    SYS_UnlockReg();

    printf("Enter power down ...\n");
    while(!IsDebugFifoEmpty());

    /* Wakeup Enable */
    USBD_ENABLE_INT(USBD_INTEN_WKEN_Msk);

    CLK_PowerDown();

    /* Clear PWR_DOWN_EN if it is not clear by itself */
    if(CLK->PWRCTL & CLK_PWRCTL_PDEN_Msk)
        CLK->PWRCTL ^= CLK_PWRCTL_PDEN_Msk;

    printf("device wakeup!\n");

    /* Lock protected registers */
    SYS_LockReg();
}

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

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

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

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

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

    /* 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

        /* Enter power down when USB suspend */
        if(g_u8Suspend)
            PowerDown();

        MSC_ProcessCmd();
    }
}
