1 How to update U-Boot on pico-imx7d board
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4 Required software on the host PC:
6 - imx_usb_loader: https://github.com/boundarydevices/imx_usb_loader
11 $ make pico-imx7d_defconfig
14 This generates the U-Boot binary called u-boot.imx.
16 Put pico board in USB download mode (refer to the PICO-iMX7D Quick Start Guide
19 Connect a USB to serial adapter between the host PC and pico.
21 Connect a USB cable between the OTG pico port and the host PC.
23 Open a terminal program such as minicom.
25 Copy u-boot.imx to the imx_usb_loader folder.
27 Load u-boot.imx via USB:
29 $ sudo ./imx_usb u-boot.imx
31 Then U-Boot starts and its messages appear in the console program.
33 Use the default environment variables:
41 Transfer u-boot.imx to be flashed into the eMMC:
43 $ sudo dd if=u-boot.imx of=/dev/sdX bs=1K seek=1; sync
45 Remove power from the pico board.
47 Put pico board into normal boot mode.
49 Power up the board and the new updated U-Boot should boot from eMMC.
51 Building U-Boot to boot with NXP 4.1 kernel:
53 The NXP 4.1 kernel boots only in secure boot mode on mx7.
55 Follow the next steps to enable secure boot:
58 $ make pico-imx7d_defconfig
61 -> [*] Enable support for booting in non-secure mode
62 -> [*] Boot in secure mode by default
66 Flash u-boot.imx using the imx_usb_loader tool.