1 How to Update U-Boot on Pico-imx6ul board
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4 Required software on the host PC:
6 - imx_usb_loader: https://github.com/boundarydevices/imx_usb_loader
8 - dfu-util: http://dfu-util.sourceforge.net/releases/
10 Build U-Boot for Pico:
13 $ make pico-imx6ul_defconfig
16 This will generate the U-Boot binary called u-boot.imx.
18 Put pico board in USB download mode (refer to the document
19 http://www.wandboard.org/images/hobbit/hobbitboard-imx6ul-reva1.pdf page 15)
21 Connect a USB to serial adapter between the host PC and pico
23 Connect a USB cable between the OTG pico port and the host PC
25 Open a terminal program such as minicom
27 Copy u-boot.imx to the imx_usb_loader folder.
29 Load u-boot.imx via USB:
31 $ sudo ./imx_usb u-boot.imx
33 Then U-Boot should start and its messages will appear in the console program.
35 Use the default environment variables:
43 Transfer u-boot.imx that will be flashed into the eMMC:
45 $ sudo dfu-util -D u-boot.imx -a boot
47 Then on the U-Boot prompt the following message should be seen after a
53 Remove power from the pico board.
55 Put pico board into normal boot mode
57 Power up the board and the new updated U-Boot should boot from eMMC.