On 7/6/19 5:17 AM, dng-request@??? wrote:
> Message: 5
> Date: Sat, 6 Jul 2019 16:22:33 +0800
> From: Brad Campbell<lists2009@???>
> To:dng@???
> Subject: [DNG] Raspberry Pi 4
> Message-ID:<9d5f2187-0575-650b-29f9-0d1e226cd411@???>
> Content-Type: text/plain; charset=utf-8; format=flowed
>
> G'day all,
>
> I have an old RPI3 running Jessie that I wanted to replace with a 4
> (wanted USB3 & GbE)
>
> Not wanting to re-configure or re-install I downloaded the latest
> Raspbian for the Pi4 (Buster) to use for parts.
>
> I replaced the boot partition contents straight from the Buster image.
> Had to edit cmdline text to alter the root parameter "root=/dev/mmcblk0p2".
>
> Then I simply rsynced /lib/modules and /lib/firmware across to the root
> partition (adding not replacing).
>
> It booted right up with USB, net and console functional and I was back
> in business on the new hardware.
>
> I don't use the GPU except for initial bringup, nor wlan or bluetooth.
> So I can't vouch for those, although udev certainly detects the wlan.
>
> The config.txt lines to disable wlan & bt still work also :
>
> dtoverlay=pi3-disable-bt
> dtoverlay=pi3-disable-wifi
>
> Regards,
> Brad

I tried what you've described --- put a fresh copy of
"devuan_ascii_2.0.0_arm64_raspi3.img" on an 8GB microSD card, then
copied the parts of Raspbian Buster over; but I end up with an error
"/sbin/init exists, but is not executable (error -8)", possibly
suggesting that there is a mismatch between 32-bit boot code and 64-bit
/sbin/init.

Did you make any other changes?

-- 
-Robert Montante, Ph.D.
  Department of Mathematical and Digital Sciences
  Bloomsburg University        bobmon AT bloomu DOT edu
  Bloomsburg, PA  17815        prof.montante AT gmail DOT com
  phone: 570-389-4624            montcs.bloomu.edu/~bobmon/
--