acpi_drv / platform_drv support
christian.helmuth at genode-labs.com
Wed Feb 24 15:58:50 CET 2021
On Wed, Feb 24, 2021 at 15:01:26 CET, Joerg-C. Boehme wrote:
> I have some question about the: acpi_drv and platform_drv.
> In short:
> Is acpi_drv and platform_drv are only supporting hardware boards with PCIe ?
In general, no, we do not depend on PCIe directly. Nevertheless, I
admit that we do not test PCIe-less systems in any real-world
> And start the var/run/lighttpd.iso with qemu-system-x86_64 (without -machine
> q35 parameter!)
> qemu-system-x86_64 -no-kvm -display sdl -cpu core2duo -nographic -netdev
> user,id=net0,hostfwd=tcp::5555-:80,hostfwd=tcp::5556-:443 -net
> nic,model=e1000,netdev=net0 -serial mon:stdio -m 512 -cdrom
As you discovered this is not supported. The reason is not the missing
PCIe capability but that Qemu's i440FX chipset does not support
ECAM/MMCONF (memory-mapped) PCI configuration space access. We
replaced the I/O port based PCI driver implementation by MMCONF based
access after a vivid discussion in 2018 . Thus, we may indirectly
depend on PCIe if systems lacking PCIe ports also lack MMCONF.
> * Can I somehow "manuel" configure the system on 440FX based hardware ?
In theory, you could generate the acpi_drv report by hand. But that's
not my playground.
> * Is there a reason why platform_drv is not supporting older hardware ?
We switched to MMCONF because of demand from the community and the
promise that it's widely available. We never considered to support
both PCI-config access options for complexity and testing effort
https://www.genode-labs.com/ · https://genode.org/
https://twitter.com/GenodeLabs · /ˈdʒiː.nəʊd/
Genode Labs GmbH · Amtsgericht Dresden · HRB 28424 · Sitz Dresden
Geschäftsführer: Dr.-Ing. Norman Feske, Christian Helmuth
More information about the users