#define BANK0_APP_START 0x00002000
#define BANK1_APP_START 0x00042000

uint32_t gVer_info_LB0, gVer_info_LB1;
bool gBankswap_conduct;

int main(void)
{
    SYSCFG_DL_init();

    /* Get version information */
    gVer_info_LB0 = *((uint32_t*)BANK0_APP_START);
    gVer_info_LB1 = *((uint32_t*)BANK1_APP_START);

    /* Decide bank swap */
    if (gVer_info_LB0 < gVer_info_LB1) {
        uint32_t* ptr_version_info = (uint32_t*)BANK1_APP_START + 1; // 0x00042004
        uint32_t* ptr_SP = (uint32_t*)BANK1_APP_START + 64; // 0x00042256

        gBankswap_conduct = true;

        /* Check App data format */
        for(int i=0; i<63; i++) {
            if(ptr_version_info[i] != 0xFFFFFFFF) {
                gBankswap_conduct = false;
            }
        }

        /* Check stack pointer, it depends on device */
        /* MSPM0G3519 RAM 64kB - 0x20210000 */
        if(*ptr_SP != 0x20210000)  {
            gBankswap_conduct = false;
        }
    }
    
    if (DL_SYSCTL_isINITDONEIssued())
    {
        start_app((uint32_t *)VECTOR_ADDRESS_BANK0);
    }
    else  //Init and SWAP
    {
        if (gBankswap_conduct){
            DL_SYSCTL_executeFromUpperFlashBank(); // set flash bank swap bit
            delay_cycles(160);
            DL_SYSCTL_issueINITDONE(); // Issue INITDOEN to trigger System Reset -> swap to bank1
        }else{
            DL_SYSCTL_executeFromLowerFlashBank(); // still execute program from bank0
            delay_cycles(160);
            DL_SYSCTL_issueINITDONE(); // Issue INITDOEN to trigger System Reset -> jump to bank0 app program
        }
    }
}

The CSC (Customer Secure Code) checks the firmware versions in Bank 0 and Bank 1 to determine whether a bank swap is required. Version information is stored at the beginning of each Bank's Application region. Specifically, the Bank 0 Application version is located at address 0x00002000, while the Bank 1 Application version is located at address 0x00042000.

After checking the version information, if the firmware in Bank 1 is the latest version, the CSC verifies the firmware header before deciding to perform a bank swap. If the firmware has an incorrect header, or if Bank 0 already contains the latest version, the bank swap is not executed.