[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20061201214631.6991.qmail@cdy.org>
Date: Fri, 1 Dec 2006 22:46:31 +0100
From: Peter Stuge <stuge-linuxbios@....org>
To: "Eric W. Biederman" <ebiederm@...ssion.com>
Cc: Greg KH <gregkh@...e.de>, Andi Kleen <ak@...e.de>,
Stefan Reinauer <stepan@...esystems.de>,
linuxbios@...uxbios.org, linux-kernel@...r.kernel.org,
"Lu, Yinghai" <yinghai.lu@....com>
Subject: Re: [LinuxBIOS] #57: libusb host program for PLX NET20DC debug device
On Fri, Dec 01, 2006 at 02:15:24PM -0700, Eric W. Biederman wrote:
> Right. For LinuxBIOS not a problem for earlyprintk in the kernel
> somethings might need to be refactored. The challenge in the
> kernel is we don't know at build to how to do a pci_read_config...
>
> The other hard part early in the kernel is the fact that the
> bar is memory mapped I/O. Which means it will need to get mapped
> into the kernels page tables.
I see.
> >> And I have some code that barely works for this already, perhaps
> >> Eric and I should work together on this :)
> >
> > I would be interested in having a look at any code for it too.
>
> Sure, I will send it out shortly. I currently have a working
> user space libusb thing (easy, but useful for my debug)
Hm - for driving which end?
> and a rude read/write to the bar from user space program that
How does that work? /dev/{port,mem}?
> allowed me to debug the worst of the state machine from user
> space. I don't think I have the state setup logic correct yet
> but that is minor in comparison.
>
> I really wish the EHCI spec had made that stupid interface 16 bytes
> instead of 8 or had a way to chain multiple access together. The
> we could have used a normal usb cable. As it is most descriptors
> are 1 byte to big to read.
Which descriptors are you reading?
The debug port isn't really supposed to be used with anything but a
debug device - which can't be enumerated normally anyway.
//Peter
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists