[Upgrading, Modifying and Unlocking] wa.v:
here is last part of log from the SP FLash tool:

(FlashToolLib/source/common/generic/src/da_entry_base.cpp:391)

02/20/18 20:19:00.506 BROM_DLL[8040][5316]: DEBUG: BRom_MT6276::Boot_FlashTool(): (000008C4): BRom_WriteBuf() ... (FlashToolLib/sv5/common/generic/src/brom_mt6276.cpp:1472)

02/20/18 20:19:00.506 BROM_DLL[8040][5316]: BRom_MT6276::BRom_WriteBuf(): p_data_blocks(0x05D8FAF0). (FlashToolLib/sv5/common/generic/src/brom_mt6276.cpp:957)

02/20/18 20:19:00.506 BROM_DLL[8040][5316]: BRom_MT6276::BRom_WriteBuf(): block_count(1), total_length(88248). (FlashToolLib/sv5/common/generic/src/brom_mt6276.cpp:1003)

02/20/18 20:19:00.506 BROM_DLL[8040][5316]: com_util::GetCommPreference(000008C4): dcb.BaudRate(921600), packet_len(1024), accuracy(2). (FlashToolLib/host/windows/com_util.cpp:542)

02/20/18 20:19:00.506 BROM_DLL[8040][5316]: BRom_MT6276::BRom_WriteBuf(): sending m_blocks[0]={ m_baseaddr(0x00200000), m_data(0x0387F84C), m_data_len(88248), m_data_sig_len(256) }. (FlashToolLib/sv5/common/generic/src/brom_mt6276.cpp:1033)

02/20/18 20:19:00.522 BROM_DLL[8040][5316]: DEBUG: BRom_Base::Write8DataWithEcho(): =0, cmd(0xD7) (FlashToolLib/sv5/common/interface/src/brom_base.cpp:1289)

02/20/18 20:19:00.709 BROM_DLL[8040][5316]: ERROR: BRom_MT6276::BRom_WriteBuf(): Read16Data(): Status returns error (0x2001)! (FlashToolLib/sv5/common/generic/src/brom_mt6276.cpp:1153)

02/20/18 20:19:00.709 BROM_DLL[8040][5316]: ~BRom_PowerKeyLockSentry(): execute m_base.SetReg_ReleasePowerKey(). (FlashToolLib/sv5/common/interface/src/brom_base.cpp:2102)

02/20/18 20:19:00.709 BROM_DLL[8040][5316]: Boot_FlashTool(): DA_HANDLE->rwlock: READ_UNLOCK. (FlashToolLib/host/windows/rwlock.cpp:423)

02/20/18 20:19:00.709 BROM_DLL[8040][5316]: ERROR: pre_download_da(): S_BROM_DOWNLOAD_DA_FAIL(2004),ft_handle(0x038CCB30): Boot_FlashTool(): fail! (FlashToolLib/sv5/common/generic/src/flashtool_api.cpp:1530)

02/20/18 20:19:00.709 BROM_DLL[8040][5316]: pre_download_da(038CCB30): DA_HANDLE->rwlock: READ_UNLOCK. (FlashToolLib/host/windows/rwlock.cpp:423)

02/20/18 20:19:00.709 BROM_DLL[8040][5316]: ERROR: FlashTool_Connect_Download_InitDA(): FlashTool_Connect_Download_InitDA() fail, error S_BROM_DOWNLOAD_DA_FAIL(2004) (FlashToolLib/sv5/common/generic/src/flashtool_api.cpp:1580)

02/20/18 20:19:00.709 BROM_DLL[8040][5316]: ERROR: FlashTool_Connect_Download_InitDA(): <ERR_CHECKPOINT>[150][error][2004]</ERR_CHECKPOINT> [S_BROM_DOWNLOAD_DA_FAIL] (FlashToolLib/sv5/common/generic/src/flashtool_api.cpp:1582)

02/20/18 20:19:00.709 BROM_DLL[8040][5316]: ERROR: FlashTool_Connect_Download_DA(): S_BROM_DOWNLOAD_DA_FAIL(2004),ft_handle(0x038CCB30): FlashTool_Connect_Download_InitDA(): fail! (FlashToolLib/sv5/common/generic/src/flashtool_api.cpp:1441)

02/20/18 20:19:00.709 BROM_DLL[8040][5316]: ERROR: FlashTool_Connect_Download_DA(): <ERR_CHECKPOINT>[149][error][2004]</ERR_CHECKPOINT> [S_BROM_DOWNLOAD_DA_FAIL] (FlashToolLib/sv5/common/generic/src/flashtool_api.cpp:1443)

02/20/18 20:19:00.896 BROM_DLL[8040][5316]: FlashTool_Disconnect(0x038CCB30): mutex: LOCK ... (FlashToolLib/host/windows/mutex.cpp:143)

02/20/18 20:19:00.896 BROM_DLL[8040][5316]: DEBUG: DA_cmd::CMD_Finish(): Send DA_FINISH_CMD(0xD9), device_status(DISCONNECT_USB_AND_RELEASE_POWERKEY). (FlashToolLib/sv5/common/generic/src/da_cmd.cpp:1048)

02/20/18 20:19:00.896 BROM_DLL[8040][5316]: ERROR: com_util::WriteComm(000008C4): retry(0), reset(0), Err(2). (FlashToolLib/host/windows/com_util.cpp:366)

02/20/18 20:19:00.896 BROM_DLL[8040][5316]: ERROR: com_util::WriteComm(000008C4): retry(1), reset(0), Err(2). (FlashToolLib/host/windows/com_util.cpp:366)

02/20/18 20:19:00.896 BROM_DLL[8040][5316]: ERROR: com_util::Reset(000008C4): SetCommState() fail! , Err(31). (FlashToolLib/host/windows/com_util.cpp:320)

02/20/18 20:19:00.896 BROM_DLL[8040][5316]: ERROR: com_util::WriteComm(000008C4): retry(0), reset(1), Err(2). (FlashToolLib/host/windows/com_util.cpp:366)

02/20/18 20:19:00.896 BROM_DLL[8040][5316]: ERROR: com_util::WriteComm(000008C4): retry(1), reset(1), Err(2). (FlashToolLib/host/windows/com_util.cpp:366)

02/20/18 20:19:00.896 BROM_DLL[8040][5316]: ERROR: DA_cmd::WriteData(): Retry(0): WriteComm(0/1): Err(2), total=(0/1). (FlashToolLib/sv5/common/generic/src/da_cmd.cpp:139)

02/20/18 20:19:00.896 BROM_DLL[8040][5316]: ERROR: DA_cmd::CMD_Finish(): Error return(1). (FlashToolLib/sv5/common/generic/src/da_cmd.cpp:1082)

02/20/18 20:19:00.912 BROM_DLL[8040][5316]: DEBUG: DA_cmd::CMD_Finish(): OK! (FlashToolLib/sv5/common/generic/src/da_cmd.cpp:1088)

02/20/18 20:19:00.912 BROM_DLL[8040][5316]: ERROR: FlashTool_Disconnect(): (0x038CCB30): da_cmd.CMD_Finish(): fail! (FlashToolLib/sv5/common/generic/src/flashtool_api.cpp:2174)

02/20/18 20:19:00.912 BROM_DLL[8040][5316]: FlashTool_Disconnect(0x038CCB30): mutex: UNLOCK. (FlashToolLib/host/windows/mutex.cpp:158)

02/20/18 20:19:00.912 BROM_DLL[8040][5316]: com_sentry::Close(\\?\usb#vid_0e8d&pid_2000#5&1280f5eb&0&2#{a5dcbf10-6530-11d2-901f-00c04fb951ed}, 000008C4): OK! (FlashToolLib/host/windows/com_sentry.cpp:663)

02/20/18 20:19:00.912 BROM_DLL[8040][5316]: com_base::~com_base() m_hCOM(FFFFFFFF) (FlashToolLib/host/windows/com_sentry.cpp:122)

02/20/18 20:19:00.912 BROM_DLL[8040][5316]: DEBUG: FlashTool_Disconnect(): successfully done. (FlashToolLib/sv5/common/generic/src/flashtool_api.cpp:2186)

02/20/18 20:19:00.927 BROM_DLL[8040][8176]: RB_ClearAll(): RB_HANDLE->rwlock: WRITE_TRYLOCK, OK! (FlashToolLib/host/windows/rwlock.cpp:446)

02/20/18 20:19:00.927 BROM_DLL[8040][8176]: RB_ClearAll(): RB_HANDLE->rwlock: WRITE_UNLOCK. (FlashToolLib/host/windows/rwlock.cpp:476)