NXP i.MX8MQ EVK Evaluation Board ================================ Board comes with: * 3GiB of LPDDR4 RAM * 16GiB eMMC Not including booting via serial, the device can boot from either SD or eMMC. Downloading DDR PHY and HDMI/eDP Firmware ----------------------------------------- As a part of DDR intialization routine NXP i.MX8MQ EVK requires and uses several binary firmware blobs that are distributed under a separate EULA and cannot be included in Barebox. In order to obtain them do the following:: wget https://www.nxp.com/lgfiles/NMG/MAD/YOCTO/firmware-imx-8.0.bin chmod +x firmware-imx-8.0.bin ./firmware-imx-8.0.bin Executing that file should produce a EULA acceptance dialog as well as result in the following files: - lpddr4_pmu_train_1d_dmem.bin - lpddr4_pmu_train_1d_imem.bin - lpddr4_pmu_train_2d_dmem.bin - lpddr4_pmu_train_2d_imem.bin As a last step of this process those files need to be placed in "firmware/":: for f in lpddr4_pmu_train_1d_dmem.bin \ lpddr4_pmu_train_1d_imem.bin \ lpddr4_pmu_train_2d_dmem.bin \ lpddr4_pmu_train_2d_imem.bin; \ do \ cp firmware-imx-8.0/firmware/ddr/synopsys/${f} \ firmware/${f}; \ done You will also need to copy the HDMITX controller firmware in order to use the HDMI and/or eDP display output:: for f in signed_dp_imx8m.bin \ signed_hdmi_imx8m.bin; \ do \ cp firmware-imx-8.0/firmware/hdmi/cadence/${f} \ firmware/${f}; \ done DDR Configuration Code ====================== The following two files: - arch/arm/boards/nxp-imx8mq-evk/ddr_init.c - arch/arm/boards/nxp-imx8mq-evk/ddrphy_train.c were obtained by running i.MX 8M DDR Tool that can be found here: https://community.nxp.com/docs/DOC-340179 Only minimal amount of necessary changes were made to those files. All of the "impedance matching" code is located in "ddr.h". Build Barebox ============= make imx_v8_defconfig make Boot Configuration ================== The NXP i.MX8MQ EVK Evaluation Board has two switches responsible for configuring bootsource/boot mode: * SW802 for selecting appropriate BMOD * SW801 for selecting appropriate boot medium In order to select internal boot set SW802 as follows:: +-----+ | | | O | | <--- on = high level | | | | | | O | <--- off = low level | | | 1 2 | +-----+ Bootsource is the internal eMMC:: +---------+ | | | | | O | | | | | | | | <---- eMMC | O O | O | | | | 1 2 3 4 | +---------+ Bootsource is the SD2 slot:: +---------+ | | | O O | | | | | | | | | <---- SD2 | | | O O | | | | 1 2 3 4 | +---------+ Serial boot SW802 setting needed for i.MX8 DDR Tool is as follows:: +-----+ | | | | O | <--- on = high level | | | | | O | | <--- off = low level | | | 1 2 | +-----+