On Wed, 19 Mar 2025, Andrew Randrianasulu wrote:
> I was reading NetBSD's
>
> sys/arch/macppc/macppc/memory.c
>
> and there is comment:
>
> *<---->The EEPROMs for Serial Presence Detect don't show up in the
> * <--->OpenFirmware tree, but their contents are available through the
>
> * <--->"dimm-info" property of the "/memory" node. To make the
> * <--->information available, we fake up an I2C bus with EEPROMs
> * <--->containing the appropriate slices of the "dimm-info" property.
>
> But I can't find "dimm-info" in openbios source tree ?
>
> Is it simply not implemented?
I think OpenBIOS knows nothing about SPD and Mac i2c so it won't look at
them. It gets memory size from fw_cfg which it adds to /memory node and
that's it. Does NetBSD work on g3beige?
yes, this is where I noticed that keyboard on cuda/adb acts strange not only in macos ..... but may be not all hosts affected that badly.
You can try that with the Apple
ROM then and see if that works.
yeah, I just need to find this rage128 option ROM ;) (dingusppc seems to get it from main rom or somewhere else ...?).
Also a bit of rebase on my end needed ...
> Reason to ask: NetBSD/macppc only can be booted with 256mb ram or less in
> Qemu.
Does it use SPD for that?
not directly, as comment indicates. Linux/macos/ISX happy with way it currently set up, but NetBSD not.
I wonder if there some qemu generic machinery for providing more exact dimm sizes? I think qemu-system-x86_64 provide something via acpi ....
Most OSes just look at the /memory node as
it's simpler to get memory size from there than parsing SPD data.
Regards,
BALATON Zoltan