On Sat, 14 Dec 2019, John Paul Adrian Glaubitz wrote:
Hi!
When installing Debian/m68k inside qemu-m68k-system [1], we are
currently limited to 1 GB of physical memory which is due to a limit in
the Linux kernel as far as I know.
However, I also know that it is possible to run the m68k kernel on
Aranym with up to 3.5 GB of RAM. Thus, I was wondering whether there
would be chance we could get the kernel patched to support more than 1
GB of memory also on qemu-m68k-system which currently emulates an Apple
Macintosh Quadra 800 system.
Adrian
[1] https://wiki.debian.org/M68k/QemuSystemM68k
I believe that the reason for the limitation is the Mac memory map, as
Laurent pointed out in the issue tracker,
https://github.com/vivier/qemu-m68k/issues/42
It's theoretically possible to use NuBus slot space for additional RAM.
The super slot space ($6000 0000 thru $EFFF FFFF) is 2304 MB in size and
the standard slot space ($F100 0000 thru $FFFF FFFF) is another 239 MB.
I'm not sure about any hardware designs that took advantage of this
possibility (Radius Rocket perhaps?).
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