imx-m4-demos on IMX8

[lchen]

Hi,

Due to license for redistribution issue, I am trying to remove imx-m4-demos support from the imx8qmmek yocto image. Want to understand, what imx-m4-demos will provide? Looks it is part of the bootloader, is it essential for Cortex M4 core? Without imx-m4-demos pkg, is there any impact on the board functionality or performance?

Thanks,

Lijun

[igorpadykov · Accepted solution]

Hi Lijun

>what imx-m4-demos will provide? Looks it is part of the bootloader, is it essential for Cortex M4 core? 

m4-demos are not part of bootloader, not essential for Cortex M4 core.

>Without imx-m4-demos pkg, is there any impact on the board functionality or performance?

no impact.

Best regards
igor

[lchen]

Hi Igor,

Thanks for the reply.

How do I remove imx-m4-demos from the image. Looks add it to IMAGE_INSTALL_remove doesn't work. In sources/meta-imx/meta-bsp/conf/layer.conf and sources/meta-imx/meta-bsp/recipes-bsp/imx-mkimage/imx-boot_1.0.bb, there are a bunch of settings related to m4 module.

For example in sources/meta-imx/meta-bsp/conf/layer.conf :

# Overrides for imx8qm-mek.conf
MACHINE_FEATURES_append_imx8qm-mek = " xen nxp8997"
RDEPENDS_${KERNEL_PACKAGE_NAME}-image_imx8qm-mek = ""
IMXBOOT_TARGETS_SD_prepend_imx8qm-mek = \
 "${@bb.utils.contains('MACHINE_FEATURES', 'optee', 'flash_linux_m4', \
 'flash_regression_linux_m4', d)} "

Not sure how to disable flash_linux_m4?

Thanks,

Lijun

[lchen]

By the way, it does look like imx-m4-demos pkg includes the boot image for Cortex-M4(f).

In sources/meta-imx/meta-bsp/recipes-bsp/imx-mkimage/imx-boot_1.0.bb compile_mx8():

cp ${DEPLOY_DIR_IMAGE}/imx8qm_m4_TCM_power_mode_switch_m40.bin \
${BOOT_STAGING}/m4_image.bin
cp ${DEPLOY_DIR_IMAGE}/imx8qm_m4_TCM_power_mode_switch_m41.bin \
${BOOT_STAGING}/m4_1_image.bin

...

And

deploy_mx8() {
install -d ${DEPLOYDIR}/${BOOT_TOOLS}
install -m 0644 ${BOOT_STAGING}/${SECO_FIRMWARE_NAME} ${DEPLOYDIR}/${BOOT_TOOLS}
install -m 0644 ${BOOT_STAGING}/m4_image.bin ${DEPLOYDIR}/${BOOT_TOOLS}
install -m 0644 ${BOOT_STAGING}/m4_1_image.bin ${DEPLOYDIR}/${BOOT_TOOLS}
install -m 0755 ${S}/${TOOLS_NAME} ${DEPLOYDIR}/${BOOT_TOOLS}
if [ -e ${DEPLOY_DIR_IMAGE}/u-boot-spl.bin-${MACHINE}-${UBOOT_CONFIG} ] ; then
install -m 0644 ${DEPLOY_DIR_IMAGE}/u-boot-spl.bin-${MACHINE}-${UBOOT_CONFIG} \
${DEPLOYDIR}/${BOOT_TOOLS}
fi
}

In sources/meta-imx/meta-bsp/conf/layer.conf

# Overrides for imx8qm-mek.conf
MACHINE_FEATURES_append_imx8qm-mek = " xen nxp8997"
RDEPENDS_${KERNEL_PACKAGE_NAME}-image_imx8qm-mek = ""
IMXBOOT_TARGETS_SD_prepend_imx8qm-mek = \
"${@bb.utils.contains('MACHINE_FEATURES', 'optee', 'flash_linux_m4', \
'flash_regression_linux_m4', d)} "

All of those, they all looking for m4_image.bin and m4_1_image.bin, which are copied from imx8qm_m4_TCM_power_mode_switch_m40.bin and imx8qm_m4_TCM_power_mode_switch_m41.bin, which are part of imx-m4-demos pkgs.

Seems if we change the configuration to not use imx-m4, the Cortex-M4(f) won't be booted? Then any audio, video, or FPU related processing will be impacted?