Re: Amiga screen modes in wscons

[David Brownlee <abs%absd.org@localhost>]

On Sun, 12 Nov 2023 at 03:29, Carlos Milán Figueredo
<cmilanf%hispamsx.org@localhost> wrote:
>
> Hi Michael,
>
> I have been able to compile a WSCONS kernel changing the values of AGA screenmodes, but indeed, it requires a lot of trial to get the right values. Compiling a new kernel each time is really un-practical, so I understand why patching is preferred.
>

If you have a fast cross build box the time to rebuild a new kernel
with adjusted values is approximately nothing (though the time to copy
to the Amiga and for it to reboot into it is very much not :)

> From: port-amiga-owner%NetBSD.org@localhost <port-amiga-owner%NetBSD.org@localhost> on behalf of Michael van Elst <mlelstv%serpens.de@localhost>
> Sent: Saturday, November 11, 2023 0:11
>
> > You should be able to use gdb -w to patch the binary.
>
> Using gdb I have been able to find the variables memory addresses, but I have not been successful changing them:
>
> # gdb -w netbsd
> (gdb) info variable AGA_htotal
> 0x004635d4 pAGA_htotal
> 0x00463536 AGA_htotal
> (gdb) set {int}0x00463536 = 0x79
> Cannot access memory at address 0x00463536
>
> What am I missing?

Looking for a more general solution - the values could be optionally
passed in at boot time from the bootloader, either as parameters or by
reading from a boot.cfg file

Actually - are these values which would make sense to be able to
adjust dynamically at runtime - so via sysctl or ioctl the screenmode
could be tweaked while running?

David