Comment 0 for bug 1813133

Impact:

The dtb for the Raspberry CM3 board is not shipped in the Bionic -raspi2 kernel arm64 variant.

Fix:

The dtb for the cm3 board was not compiled at all, in the arm64 arch: apply the attached patch and recompile

How to test:

The linux-modules-*-raspi2_arm64.deb should contain the bcm2710-rpi-cm3 dtb now:

$ dpkg -x linux-modules-4.15.0-1031-raspi2_4.15.0-1031.33_arm64.deb foobar
...
$ ls -l foobar/lib/firmware/4.15.0-1031-raspi2/device-tree/broadcom/
total 92
-rw-r--r-- 1 ppisati ppisati 24566 Jan 23 12:59 bcm2710-rpi-3-b-plus.dtb
-rw-r--r-- 1 ppisati ppisati 24303 Jan 23 12:59 bcm2710-rpi-3-b.dtb
-rw-r--r-- 1 ppisati ppisati 23015 Jan 23 12:59 bcm2710-rpi-cm3.dtb
-rw-r--r-- 1 ppisati ppisati 17451 Jan 23 12:59 bcm2837-rpi-3-b.dtb

Regression potential:

The patch is trivial - it just builds the cm3 dtb if arch==arm64, and doesn't modify any existing code, so there's no regression potential at all.