1*dab14934SVanessa MaegimaHow to Update U-Boot on Pico-imx6ul board 2*dab14934SVanessa Maegima----------------------------------------- 3*dab14934SVanessa Maegima 4*dab14934SVanessa MaegimaRequired software on the host PC: 5*dab14934SVanessa Maegima 6*dab14934SVanessa Maegima- imx_usb_loader: https://github.com/boundarydevices/imx_usb_loader 7*dab14934SVanessa Maegima 8*dab14934SVanessa Maegima- dfu-util: http://dfu-util.sourceforge.net/releases/ 9*dab14934SVanessa Maegima 10*dab14934SVanessa MaegimaBuild U-Boot for Pico: 11*dab14934SVanessa Maegima 12*dab14934SVanessa Maegima$ make mrproper 13*dab14934SVanessa Maegima$ make pico-imx6ul_defconfig 14*dab14934SVanessa Maegima$ make 15*dab14934SVanessa Maegima 16*dab14934SVanessa MaegimaThis will generate the U-Boot binary called u-boot.imx. 17*dab14934SVanessa Maegima 18*dab14934SVanessa MaegimaPut pico board in USB download mode (refer to the document 19*dab14934SVanessa Maegimahttp://www.wandboard.org/images/hobbit/hobbitboard-imx6ul-reva1.pdf page 15) 20*dab14934SVanessa Maegima 21*dab14934SVanessa MaegimaConnect a USB to serial adapter between the host PC and pico 22*dab14934SVanessa Maegima 23*dab14934SVanessa MaegimaConnect a USB cable between the OTG pico port and the host PC 24*dab14934SVanessa Maegima 25*dab14934SVanessa MaegimaOpen a terminal program such as minicom 26*dab14934SVanessa Maegima 27*dab14934SVanessa MaegimaCopy u-boot.imx to the imx_usb_loader folder. 28*dab14934SVanessa Maegima 29*dab14934SVanessa MaegimaLoad u-boot.imx via USB: 30*dab14934SVanessa Maegima 31*dab14934SVanessa Maegima$ sudo ./imx_usb u-boot.imx 32*dab14934SVanessa Maegima 33*dab14934SVanessa MaegimaThen U-Boot should start and its messages will appear in the console program. 34*dab14934SVanessa Maegima 35*dab14934SVanessa MaegimaUse the default environment variables: 36*dab14934SVanessa Maegima 37*dab14934SVanessa Maegima=> env default -f -a 38*dab14934SVanessa Maegima=> saveenv 39*dab14934SVanessa Maegima 40*dab14934SVanessa MaegimaRun the DFU command: 41*dab14934SVanessa Maegima=> dfu 0 mmc 0 42*dab14934SVanessa Maegima 43*dab14934SVanessa MaegimaTransfer u-boot.imx that will be flashed into the eMMC: 44*dab14934SVanessa Maegima 45*dab14934SVanessa Maegima$ sudo dfu-util -D u-boot.imx -a boot 46*dab14934SVanessa Maegima 47*dab14934SVanessa MaegimaThen on the U-Boot prompt the following message should be seen after a 48*dab14934SVanessa Maegimasuccessful upgrade: 49*dab14934SVanessa Maegima 50*dab14934SVanessa Maegima#DOWNLOAD ... OK 51*dab14934SVanessa MaegimaCtrl+C to exit ... 52*dab14934SVanessa Maegima 53*dab14934SVanessa MaegimaRemove power from the pico board. 54*dab14934SVanessa Maegima 55*dab14934SVanessa MaegimaPut pico board into normal boot mode 56*dab14934SVanessa Maegima 57*dab14934SVanessa MaegimaPower up the board and the new updated U-Boot should boot from eMMC. 58