What does "da" mean in code?

[vaboro]

There are many objects in code containing "da" in their names: get_da_version, get_da_stor_life_check, DA_handler, configure_da, da_read, da_rl and many more.
What is the meaning of "da" in them?

[bkerler]

DA means Download Agent.

[vaboro]

Thank you for prompt reply.

1. When I run mtkclient from a LiveCD I get the following output:

   LiveCD terminal output

   Port - Device detected :)
   Preloader - 	CPU:			MT6739/MT6731()
   Preloader - 	HW version:		0x0
   Preloader - 	WDT:			0x10007000
   Preloader - 	Uart:			0x11002000
   Preloader - 	Brom payload addr:	0x100a00
   Preloader - 	DA payload addr:	0x201000
   Preloader - 	CQ_DMA addr:		0x10212000
   Preloader - 	Var1:			0xb4
   Preloader - Disabling Watchdog...
   Preloader - HW code:			0x699
   Preloader - Target config:		0xe3
   Preloader - 	SBC enabled:		True
   Preloader - 	SLA enabled:		True
   Preloader - 	DAA enabled:		False
   Preloader - 	SWJTAG enabled:		True
   Preloader - 	EPP_PARAM at 0x600 after EMMC_BOOT/SDMMC_BOOT:	False
   Preloader - 	Root cert required:	False
   Preloader - 	Mem read auth:		True
   Preloader - 	Mem write auth:		True
   Preloader - 	Cmd 0xC8 blocked:	True
   Preloader - Get Target info
   Preloader - BROM mode detected.
   Preloader - 	HW subcode:		0x8a00
   Preloader - 	HW Ver:			0xca00
   Preloader - 	SW Ver:			0x0
   Preloader - ME_ID:			534A2D10983E6110E03F0E4A3AC5DD31
   Preloader - SOC_ID:			476090BFDE0E87D78B0E66A22E097C243C5942ABF675CEBAF94F2AC15F9CC8A5
   Port - Device detected :)
   Successfully extracted preloader for this device to: preloader_dura64.bin
   DAXFlash - Uploading xflash stage 1 from MTK_AllInOne_DA_5.2152.bin
   xflashext - Patching da2 ...
   DAXFlash - Successfully uploaded stage 1, jumping ..
   Preloader - Jumping to 0x200000
   Preloader - Jumping to 0x200000: ok.
   DAXFlash - Successfully received DA sync
   DAXFlash - Sending emi data ...
   DAXFlash - DRAM setup passed.
   DAXFlash - Sending emi data succeeded.
   DAXFlash - Uploading stage 2...
   DAXFlash - Upload data was accepted. Jumping to stage 2...
   DAXFlash - Successfully uploaded stage 2
   DAXFlash - EMMC FWVer:      0x0
   DAXFlash - EMMC ID:         QE63MB
   DAXFlash - EMMC CID:        150100514536334d42033befd353250b
   DAXFlash - EMMC Boot1 Size: 0x400000
   DAXFlash - EMMC Boot2 Size: 0x400000
   DAXFlash - EMMC GP1 Size:   0x0
   DAXFlash - EMMC GP2 Size:   0x0
   DAXFlash - EMMC GP3 Size:   0x0
   DAXFlash - EMMC GP4 Size:   0x0
   DAXFlash - EMMC RPMB Size:  0x400000
   DAXFlash - EMMC USER Size:  0x3a3e00000
   DAXFlash - HW-CODE         : 0x699
   DAXFlash - HWSUB-CODE      : 0x8A00
   DAXFlash - HW-VERSION      : 0xCA00
   DAXFlash - SW-VERSION      : 0x0
   DAXFlash - CHIP-EVOLUTION  : 0x0
   DAXFlash - DA-VERSION      : 1.0
   DAXFlash - Upload data was accepted. Jumping to stage 2...
   DAXFlash - DA Extensions successfully added
   

2. But when I run mtkclient from a cloned repo on the host machine I get the following output:

   Cloned repo terminal output

   Port - Device detected :)
   Preloader - 	CPU:			MT6739/MT6731/MT8765()
   Preloader - 	HW version:		0x0
   Preloader - 	WDT:			0x10007000
   Preloader - 	Uart:			0x11002000
   Preloader - 	Brom payload addr:	0x100a00
   Preloader - 	DA payload addr:	0x201000
   Preloader - 	CQ_DMA addr:		0x10212000
   Preloader - 	Var1:			0xb4
   Preloader - Disabling Watchdog...
   Preloader - HW code:			0x699
   Preloader - Target config:		0xe3
   Preloader - 	SBC enabled:		True
   Preloader - 	SLA enabled:		True
   Preloader - 	DAA enabled:		False
   Preloader - 	SWJTAG enabled:		True
   Preloader - 	EPP_PARAM at 0x600 after EMMC_BOOT/SDMMC_BOOT:	False
   Preloader - 	Root cert required:	False
   Preloader - 	Mem read auth:		True
   Preloader - 	Mem write auth:		True
   Preloader - 	Cmd 0xC8 blocked:	True
   Preloader - Get Target info
   Preloader - BROM mode detected.
   Preloader - 	HW subcode:		0x8a00
   Preloader - 	HW Ver:			0xca00
   Preloader - 	SW Ver:			0x0
   Preloader - ME_ID:			534A2D10983E6110E03F0E4A3AC5DD31
   Preloader - SOC_ID:			476090BFDE0E87D78B0E66A22E097C243C5942ABF675CEBAF94F2AC15F9CC8A5
   Port - Device detected :)
   DAXFlash - Uploading xflash stage 1 from MTK_AllInOne_DA_5.2152.bin
   xflashext - Patching da1 ...
   xflashext
   xflashext - [LIB]: Error on patching da1 version check...
   xflashext - Patching da2 ...
   DAXFlash - Successfully uploaded stage 1, jumping ..
   Preloader - Jumping to 0x200000
   Preloader - Jumping to 0x200000: ok.
   DAXFlash - Successfully received DA sync
   DAXFlash - Sending emi data ...
   DAXFlash - DRAM setup passed.
   DAXFlash - Sending emi data succeeded.
   DAXFlash - Uploading stage 2...
   DAXFlash - Upload data was accepted. Jumping to stage 2...
   DAXFlash - Successfully uploaded stage 2
   DAXFlash - EMMC FWVer:      0x0
   DAXFlash - EMMC ID:         QE63MB
   DAXFlash - EMMC CID:        150100514536334d42033befd353250b
   DAXFlash - EMMC Boot1 Size: 0x400000
   DAXFlash - EMMC Boot2 Size: 0x400000
   DAXFlash - EMMC GP1 Size:   0x0
   DAXFlash - EMMC GP2 Size:   0x0
   DAXFlash - EMMC GP3 Size:   0x0
   DAXFlash - EMMC GP4 Size:   0x0
   DAXFlash - EMMC RPMB Size:  0x400000
   DAXFlash - EMMC USER Size:  0x3a3e00000
   DAXFlash - HW-CODE         : 0x699
   DAXFlash - HWSUB-CODE      : 0x8A00
   DAXFlash - HW-VERSION      : 0xCA00
   DAXFlash - SW-VERSION      : 0x0
   DAXFlash - CHIP-EVOLUTION  : 0x0
   DAXFlash - DA-VERSION      : 1.0
   DAXFlash - Upload data was accepted. Jumping to stage 2...
   DAXFlash - DA Extensions successfully added
   

In the second example there is no message about successful preloader extraction, and then an error on patching da1 version check occurs. What may be going wrong here?

UPDATE:

I think I figured out the answer.
The message "Successfully extracted preloader for this device to: preloader_dura64.bin" appears only when preloader is extracted for the first time. As soon as the file preloader_dura64.bin is present, the message doesn't appear any more.
The "Error on patching da1 version check..." doesn't appear when running from a LiveCD because the call to patch_da1(da1) is commented out in /opt/mtkclient/Library/mtk_daxflash.py on line 1034, whereas it's not when running on the host machine.

What was the reason for da1 and da2 though?