1********************************* 2Technexion i.MX8M Mini Pico board 3********************************* 4 5This file documents the Buildroot support for the Technexion i.MX8M 6Mini Pico board. The Pico i.MX8M Mini system-on-module [1] is present 7in development kits like the Pico Pi i.MX8M Mini [2]. 8 9Build 10===== 11 12First, configure Buildroot for the i.MX8M Mini Pico board: 13 14 make imx8mmpico_defconfig 15 16Build all components: 17 18 make 19 20You will find in output/images/ the following files: 21 - bl31.bin 22 - boot.vfat 23 - Image 24 - imx8-boot-sd.bin 25 - imx8mm-pico-pi.dtb 26 - imx8mm-pico-pi-ili9881c.dtb 27 - imx8mm-pico-pi-sn65dsi84-hj070na.dtb 28 - lpddr4_pmu_train_fw.bin 29 - rootfs.ext2 30 - rootfs.ext4 31 - sdcard.img 32 - u-boot.imx 33 34Flashing sdcard.img on the eMMC 35=============================== 36 37i.MX8M Mini Pico board does not have a SD card slot. The storage is an 38eMMC. An easy way to flash the eMMC is to use the u-boot ums 39command. The boards are sold pre-flashed with such a u-boot. It is 40assumed here that the board has already a working u-boot on eMMC and 41jumpers are set to boot on eMMC. See [3]. 42 43Jumper configuration for eMMC boot: 44J1: jumper on pins 4 and 6. 45J2: jumper on pins 2 and 4. 46 47In case the board was flashed with a wrong u-boot, or the eMMC is 48erased, u-boot can be loaded by USB Serial Download boot mode, using 49imx-usb-loader. See [3] and [4]. 50 51For flashing: 52- Plug the micro USB cable from the Debug USB Port, to your computer 53- Plug the USB Type C to your computer, this will power up the board 54 55In the U-Boot prompt launch: 56 57=> ums 0 mmc 1 58 59This will mount the eMMC content in the host PC as a mass storage device. 60 61To determine the device associated to the eMMC card have a look in the 62/proc/partitions file: 63 64 cat /proc/partitions 65 66If your system automatically mount some device partitions, make sure 67to unmount them. 68 69Buildroot prepares a bootable "sdcard.img" image in the output/images/ 70directory, ready to be dumped on the eMMC. Launch the following 71command as root: 72 73 dd if=output/images/sdcard.img of=/dev/<your-sd-device> 74 75*** WARNING! This will destroy all the eMMC content. Use with care! *** 76 77This operation can take several minutes, depending on the image 78size. When tested, a 2MB/s transfer rate was observed. 79 80For details about the medium image layout, see the definition in 81board/freescale/common/imx/genimage.cfg.template. 82 83Boot the i.MX8M Mini Pico board 84=============================== 85 86To boot your newly created system: 87- put a micro USB cable into the Debug USB Port and connect using a terminal 88 emulator at 115200 bps, 8n1; 89- power on the board, with USB Type C connector. 90 91Enjoy! 92 93[1]. https://www.technexion.com/products/system-on-modules/pico/pico-compute-modules/detail/PICO-IMX8M-MINI 94[2]. https://www.technexion.com/products/pico-evaluation-kits/detail/PICOPIIMX8MM1GDEV 95[3]. https://www.technexion.com/support/knowledgebase/boot-configuration-settings-for-pico-baseboards/ 96[4]. https://www.technexion.com/support/knowledgebase/loading-bootable-software-images-onto-the-emmc-of-picosom-on-pico-pi/ 97