On 02/05/14 11:59, BALATON Zoltan wrote:
Hello,
I'm trying to improve the emulation of new world Macs (mac99) in QEMU and noticed that OpenBIOS does not support usb keyboards thus it currently cannot be used with qemu-system-ppc64 -machine mac99 and still uses an ADB keyboard for new world G4 mac that usually have USB keyboards. Because of this I have looked at adding a usb driver to OpenBIOS.
I was looking for other open source drivers to adapt but most I could find were GPLv3 (Grub), LGPLv3 (SeaBios) which are incompatible with the current OpenBIOS license or too difficult to adapt (Linux). This mostly left the driver in Coreboot's libpayload library (http://review.coreboot.org/gitweb?p=coreboot.git;a=tree;f=payloads/libpayloa...) which is BSD licensed that I gave a try. It wasn't too difficult to port to OpenBIOS but when I tried to use it it turned out that it does not handle the device being little endian on a big endian host and thus does not work correctly with ppc (but it might work on little endian hosts, I didn't test that; Coreboot libpayload seems to only support x86 and armv7.)
Fixing this is a bit tedious that I don't feel like doing now, I'd rather work on other problems towards my goal of running MorphOS on QEMU instead but I'd like to share the results so far in case someone wants to look at it, has any idea how to easily fix the endianness problem or maybe help with finishing it. Or if someone knows about another simple boot time driver that could be adapted instead and works correctly on big endian hosts please let me know.
The current work in progress version can be found here: http://goliat.eik.bme.hu/~balaton/openbios-usbhid-driver-wip.tar.xz
Any comments/help are welcome.
Rather than keep a tarball around, it may be better to keep your changes in a git repository forked from openbios.git on github or similar so that the changes can easily be rebased as time goes on.
If there was demand for USB functionality I'd consider looking into this as/when time allows, however for the long term, I'd prefer to see less C in OpenBIOS (particularly for new functionality) as the C-Forth hybrid tends to make debugging a pain when trying to switch between Forth/C stacks :/
ATB,
Mark.