1 How to update U-Boot on pico-imx7d board
2 ----------------------------------------
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 SPL and u-boot-dtb.img binaries.
16 1. Loading U-Boot via USB Serial Download Protocol
18 Note: This method is convenient for development purposes.
19 If the eMMC has already a U-Boot flashed with DFU support then
20 the user can go to step 2 below in order to update U-Boot.
22 Put pico board in USB download mode (refer to the PICO-iMX7D Quick Start Guide
25 Connect a USB to serial adapter between the host PC and pico.
27 Connect a USB cable between the OTG pico port and the host PC.
29 Note: Some computers may be a bit strict with USB current draw and will
30 shut down their ports if the draw is too high. The solution for that is
31 to use an externally powered USB hub between the board and the host computer.
33 Open a terminal program such as minicom.
35 Copy SPL and u-boot-dtb.img to the imx_usb_loader folder.
37 Load the SPL binary via USB:
41 Load the u-boot-dtb.img binary via USB:
43 $ sudo ./imx_usb u-boot-dtb.img
45 Then U-Boot starts and its messages appear in the console program.
47 Use the default environment variables:
52 2. Flashing U-Boot into the eMMC
54 Run the DFU agent so we can flash the new images using dfu-util tool:
58 Flash SPL and u-boot-dtb.img into the eMMC running the following commands on a PC:
60 $ sudo dfu-util -D SPL -a spl
62 $ sudo dfu-util -D u-boot-dtb.img -a u-boot
64 Remove power from the pico board.
66 Put pico board into normal boot mode.
68 Power up the board and the new updated U-Boot should boot from eMMC.
70 Booting in Falcon mode
71 ======================
73 Generate a uImage kernel:
75 $ make imx_v6_v7_defconfig (Using the default imx_v6_v7_defconfig configuration
76 just for an example. In order to boot faster the user should customize the
77 defconfig by only enabling the minimal required drivers).
79 $ make -j4 uImage LOADADDR=0x80008000
81 $ cp arch/arm/boot/uImage /tftpboot
82 $ cp arch/arm/boot/dts/imx7d-pico-pi.dtb /tftpboot
86 Setup the server and board IP addresses:
87 => setenv serverip 192.168.0.10
88 => setenv ipaddr 192.168.0.11
91 => tftp ${fdt_addr} imx7d-pico-pi.dtb
94 => tftp ${loadaddr} uImage
96 Write the kernel at 2MB offset:
97 => mmc write ${loadaddr} 0x1000 0x5000
100 => setenv bootargs 'console=ttymxc4,115200 root=/dev/mmcblk2p1 rootfstype=ext4 rootwait rw'
103 => spl export fdt ${loadaddr} - ${fdt_addr}
104 ## Booting kernel from Legacy Image at 80800000 ...
105 Image Name: Linux-5.2.14
106 Image Type: ARM Linux Kernel Image (uncompressed)
107 Data Size: 9077544 Bytes = 8.7 MiB
108 Load Address: 80008000
109 Entry Point: 80008000
110 Verifying Checksum ... OK
111 ## Flattened Device Tree blob at 83000000
112 Booting using the fdt blob at 0x83000000
114 Using Device Tree in place at 83000000, end 8300b615
115 subcommand not supported
116 subcommand not supported
117 Using Device Tree in place at 83000000, end 8300e615
118 Argument image is now in RAM: 0x83000000
121 Write 1MB of args data (0x800 sectors) to 1MB offset (0x800 sectors):
123 => mmc write ${fdt_addr} 0x800 0x800
125 In order to boot with Falcon mode, activate the CONFIG_SPL_OS_BOOT
126 option in the defconfig
128 --- a/configs/pico-imx7d_defconfig
129 +++ b/configs/pico-imx7d_defconfig
130 @@ -67,3 +67,4 @@ CONFIG_USB_GADGET_VENDOR_NUM=0x0525
131 CONFIG_USB_GADGET_PRODUCT_NUM=0xa4a5
134 +CONFIG_SPL_OS_BOOT=y
138 $ make pico-imx7d_defconfig
144 Flash the new binaries:
146 $ sudo dd if=SPL of=/dev/sdX bs=1k seek=1; sync
147 $ sudo dd if=u-boot-dtb.img of=/dev/sdX bs=1k seek=69; sync
149 And then SPL binary will load and jump directly to the kernel:
151 U-Boot SPL 2019.10-rc3-00284-g001c8ea94a-dirty (Sep 10 2019 - 12:46:01 -0300)
152 Trying to boot from MMC1
153 [ 0.000000] Booting Linux on physical CPU 0x0
154 [ 0.000000] Linux version 5.2.14 (fabio@fabio-OptiPlex-7010) (gcc version 7.4.0 (Ubuntu/Linaro 7.4.0-1ubuntu1~18.04.1)) #30 SMP Wed Sep 10 12:36:27 -03 2019
155 [ 0.000000] CPU: ARMv7 Processor [410fc075] revision 5 (ARMv7), cr=10c5387d
156 [ 0.000000] CPU: div instructions available: patching division code
157 [ 0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing instruction cache
158 [ 0.000000] OF: fdt: Machine model: TechNexion PICO-IMX7D Board and PI baseboard