In 5.4 Focal CONFIG_QRTR depends on ARCH_QCOM, which is a platform config that enables ARMv8 based Qualcomm chipsets, so it can not be enabled on amd64. Also CONFIG_QRTR_MHI is not present in 5.4, which means that the implementation is incomplete with respect to what modemmanager is expecting.
In later releases like Jammy, CONFIG_QRTR has no dependency on ARCH_QCOM and therefore is enabled on amd64. All QRTR modules are also there.
Enabling QRTR in 5.4 kernel would require backporting patches to remove its dependence on ARCH_QCOM and to add MHI module.
It is suggested to check modulemanager implementation whether hard requirement on QRTR modules can be skipped on amd64.
In 5.4 Focal CONFIG_QRTR depends on ARCH_QCOM, which is a platform config that enables ARMv8 based Qualcomm chipsets, so it can not be enabled on amd64. Also CONFIG_QRTR_MHI is not present in 5.4, which means that the implementation is incomplete with respect to what modemmanager is expecting.
In later releases like Jammy, CONFIG_QRTR has no dependency on ARCH_QCOM and therefore is enabled on amd64. All QRTR modules are also there.
Enabling QRTR in 5.4 kernel would require backporting patches to remove its dependence on ARCH_QCOM and to add MHI module.
It is suggested to check modulemanager implementation whether hard requirement on QRTR modules can be skipped on amd64.