Is it possible to write compiled Yocto u-boot image over uuu tool to SD card?

[HEXER]

Greetings.

HELLO  community. I am new here and i am not native English speaker. I am from Turkey.

I have a MaaxBoard which has I.MX8MQ Soc in it. This board doesnt have a physical eMMC chip only have SD card option.

I have successfully compiled a Yocto image and burned it to my SD card via balenaEtcher application. It took about 4-5 hours to complete burning to my SD card. I am sure I have not a good usb sd card reader/writer device so ı want to use this board as a image writer.

There are two USB 3.0 ports on this board and one of them has a "Device" functionality (lower one). I connected this port to my windows machine, opened a console and typed .\uuu.exe -lsblk. This is the output:

PS C:\Users\xeh\Desktop\maaxboard\uuu> .\uuu.exe -lsusb
uuu (Universal Update Utility) for nxp imx chips -- libuuu_1.5.4-0-gbdea8bd

Connected Known USB Devices
Path Chip Pro Vid Pid BcdVersion
==================================================
2:4 MX8MQ SDP: 0x1FC9 0x012B 0x0001

so, i need to know that is it possible to write compiled Yocto u-boot image over uuu tool to SD card? if so please assist me.

Best regards.

[AldoG]

Hello,

Yes, it is indeed possible, as long as your Uboot image have fastboot utility enabled it should work. Please make sure that your defconfig have this enabled.

CONFIG_CMD_FASTBOOT=y
CONFIG_USB_FUNCTION_FASTBOOT=y
CONFIG_FASTBOOT_UUU_SUPPORT=y
CONFIG_FASTBOOT=y
CONFIG_FASTBOOT_BUF_ADDR=0x42800000
CONFIG_FASTBOOT_BUF_SIZE=0x40000000
CONFIG_FASTBOOT_FLASH=y

For flashing using UUU to SD card you'll need to use the following command:
uuu -b sd <Uboot bootloader>

Best regards,
Aldo.

[HEXER]

Sorry for my late reply, ı have some health issues and i cannot sit to a chair.

Actually, what i was searching was UMS mode and UMS mode in U-Boot solved my issue.

But i am getting slow speeds. When i run "mmc info" command it says "High Speed" and "Speed: 50000000Hz (50Mhz)". This board has i.MX8MQ soc and RM tells that it supports UHS104 mode of operation which is way faster than High Speed mode.

I checked dts files and defconfig files but i couldnt encounter any hint about the slow speed mode. Than ı come up with that may be applying logic level to some GPIO pins activates this mode and ı find out that "BOOT_CFG[3:1]" sets the "SD speed mode" according to the section 6.1.5.2.1 in the RM. At the end of the table it says basicly that i can set these bits over GPIO if BT_FUSE_SEL=0.

Wold you like to assit/help me? I can provide more details if you are interested.

Best regards.