答复: 答复: 答复: Getting Started with freebios2!

[YhLu]

So the LinuxBIOS need to 
1. init USB controller
2. create usb_dev to be serial.
3. use usb_control_msg and usb_bulk_msg to talk with the serial device.

What the USB type, OHCI or UCHI or EHCI??

I wonder if some source code or documents that define No 3 above?

Regards

YH

-----邮件原件-----
发件人: ron minnich [mailto:[e-mail]] 
发送时间: 2004年5月27日 14:23
收件人: YhLu
抄送: Jay Miller; [e-mail]; LinuxBIOS
主题: Re: 答复: 答复: Getting Started with freebios2!

On Thu, 27 May 2004, YhLu wrote:
> Usb to serial ???

yes, it's now needed :-(

ron

[Steven James]

Greetings,

I'm finally getting dug out after being snowed under :-)

The spec is probably part of:
http://www.usb.org/developers/devclass_docs/usbcdc11.pdf

The communications class. I'm guessing it would be a subset of POTS modem
with a transparent data protocol. That would imply line contol on the
control ep, and either bulk transfer or isochronous pipe pairs for the
serial data.

It's a lot more involved than a simple UART, that's for sure.

On a side note, I THOUGHT I would have time by now to bang on the USB
boot. Hopefully, I'll be able to do more with it now (so I say :-)

As soon as I get up to speed on freebios2, I'll have a good test platform.

For the serial, UHCI and OHCI will be good. EHCI can likely be ignored for
the BIOS since fast devices are required to fall back and EHCI always has
one of UHCI or OHCI to handle low speed USB.

G'day,
sjames

-------------------------steven james, director of research, linux labs
... ........ ..... ....                    230 peachtree st nw ste 2701
the original linux labs                             atlanta.ga.us 30303
      -since 1995                              http://www.linuxlabs.com
                                              office & fax [phone]
-----------------------------------------------------------------------

On Thu, 27 May 2004, YhLu wrote:
> So the LinuxBIOS need to
> init USB controller
> create usb_dev to be serial.
> use usb_control_msg and usb_bulk_msg to talk with the serial device.
>
> What the USB type, OHCI or UCHI or EHCI??
>
> I wonder if some source code or documents that define No 3 above?
>
> Regards
>
> YH
>
> -----邮件原件-----
> 发件人: ron minnich [mailto:[e-mail]]
> 发送时间: 2004年5月27日 14:23
> 收件人: YhLu
> 抄送: Jay Miller; [e-mail]; LinuxBIOS
> 主题: Re: 答复: 答复: Getting Started with freebios2!
>
> On Thu, 27 May 2004, YhLu wrote:
> > Usb to serial ???
>
> yes, it's now needed :-(
>
> ron
> _______________________________________________
> Linuxbios mailing list
> [e-mail]
> http://www.clustermatic.org/mailman/listinfo/linuxbios

答复: 答复: 答复: Getting Started with freebios2!

Steven James  writes:
> For the serial, UHCI and OHCI will be good. EHCI can likely be ignored for
> the BIOS since fast devices are required to fall back and EHCI always has
> one of UHCI or OHCI to handle low speed USB.

Actually not.  At least not for serial before the memory is initialized.

For early serial only EHCI is an option.  The EHCI debug port can be used
with just I/O to the EHCI, no DMA is require.  OHCI, UHCI, and normal
EHCI require DMA transfers so they are not an option.

Eric