Re: AmigaOS 3.2 kickstart ROM crashing on NetBSD partitions (Was NetBSD/amiga sysinst)

David Brownlee <[email protected]> Fri, 24 Mar 2023 13:59:56 +0000
Newsgroups gmane.os.netbsd.ports.amiga
Message-ID <CAGN_6pZDG6U3MiTwDJ8PgTEbgxHNKK=22+dt8e9xamtY_bd-tA@mail.gmail.com>
On Fri, 24 Mar 2023 at 12:35, Frank Wille <[email protected]> wrote:
>
> On Fri, 24 Mar 2023 11:57:32 +0100 (CET)
> Karoly Balogh <[email protected]> wrote:
>
> > I'm not too experienced in debugging boot sectors, sadly, but surely some
> > hardwired serial-debug messages can be patched up using
> > exec.library/RawDoFmt() to track the progress.
>
> Or simply debug it in UAE, by setting an instruction breakpoint in the
> boot block, like
>   fi cf4f
> (0xcf4f = exg a7,a7 - which certainly doesn't trigger anywhere else)

Potentially its "just" a matter of adjusting the stubs
https://nxr.netbsd.org/xref/src/sys/arch/amiga/stand/bootblock/boot/libstubs.s
used by the bootloader (which is built as a "normal" NetBSD binary
then adjusted to be suitable for loading by AmigaOS
https://nxr.netbsd.org/xref/src/sys/arch/amiga/stand/bootblock/ )
("just" is doing a lot of heavy lifting there)

Any m68k coder up to a little assembly challenge and debugging? :) (It
should be relatively quick to setup a host system to rebuild the
NetBSD boot blocks and write them to an appropriate location in an hdf
file if you're using UAE to debug - I can certainly help with that for
anyone less familiar with the NetBSD side :)

David