-----Original Message----- From: coreboot-bounces+joe=settoplinux.org@coreboot.org [mailto:coreboot- bounces+joe=settoplinux.org@coreboot.org] On Behalf Of Patrick Georgi Sent: Thursday, July 03, 2008 9:44 PM To: Joseph Smith Cc: Stefan Reinauer; coreboot@coreboot.org Subject: Re: [coreboot] USB debug cables and emulation
Joseph Smith schrieb:
We're pretty far with the UHCI stack in GRUB2. If you are looking for a USB project to jump on, we can certainly use help ;-)
Initial keyboard support is there. MSC support is there, UHCI is there.
Missing: Fixes, Testing, OHCI, EHCI, Fixes, Fixes, Testing...
Maybe we can pack it into libpayload instead of GRUB2 too, so we can make it available to more payloads?
It's clean code with no imports (though I got some clues from other sources, esp. as far as workarounds for chipset bugs are concerned, but it should be safe), so it's not bound to a license, and apart from grub_strcpy here and grub_uint32_t there, which can be sanitized easily, and some trivial pci controller detection logic, it's not very grub2 specific either. I merely develop it inside the grub2 tree because that's the most convenient for now.
Stefan, I would love to help out. I offered my services to Patrick a
while
ago, with no response. What can I do?
Oops, sorry! You seem to be only starting into USB now, but so did I when I started writing this code (which probably shows at places). I quickly collected a TODO:
For UHCI:
- testing and fixes, lots of it
- make more clever (eg. bulk transfer with >1 packet/ms, which might be
done next week already)
- fix some abstractions (eg. bulk transfer is at the wrong place
currently)
- improve interrupt transfer handling
For OHCI:
- create driver (most of UHCI doesn't apply here, because the chip is
more clever. "fix some abstractions" definitely helps, though)
For EHCI:
- figure out how to gain control over a device from the USB1 controller
(that will somehow interact with the USB1 driver)
- PING/DATA2 protocol, microframes support
- extend HUB driver, so it handles USB1 devices on a USB2 hub
USB devices:
- the keyboard driver is rather rudimentary
- mouse doesn't exist
- mass storage only likes few devices (high priority for me)
- hub driver doesn't have proper device power management yet
Get the code to run, figure out the design (sorry, no documentation yet
- but ask me. The code can only become better that way), play with it,
fix it for your hardware, ask questions, send/commit patches, ...
On my personal TODO (after this %!$# northbridge works for me) is most of the UHCI stuff, and mass storage. Everything else is pretty much free for grabs (but it might be good to tell me so I don't step on your toes). OHCI and mouse are definitely not on my list for the short term, other usb device drivers also aren't. I also don't mind patches to any part of the code :-)
Great. I am going to be on vacation next week. I am about half way through reading the USB 2.0 specification (http://www.usb.org/developers/docs/), and I will try to finish by next week and dive right in when I get back :-)
Thanks, Joseph Smith Set-Top-Linux www.settoplinux.org