On Sun, 24 Mar 2002, Val Henson wrote:

On Sun, Mar 24, 2002 at 01:20:48PM +0100, Benjamin Herrenschmidt wrote:

quoted

We define a special BI_DEVICE type of bi_rec that represents
a HW device for which the firmware provides some informations. Since
the firmware is free to provide whatever informations it want (that
set is not fully defined), the content of the BI_DEVICE record is itself
a list of bi_recs.

<snip>

quoted

The "standard" kernel only define a few BI_DEV_TYPE's (like PCI,
4xx OCP, 8xx OCP). Drivers define attributes they can read from the
BI_DEVICE (4xx ethernet can read a HW eth adress for example).
Board vendors are free to provide additional information in the
BI_DEVICE, and add the ability to the driver (patches welcome) to
make good use of that information ;) (Could be, for example, wiring
of the PHY since it may not use MII, etc...).

What do you think ?

I had an amazing and brilliant insight (which I'm sure everyone else
has already had). :) The kernel just ignores bi_recs it doesn't
understand.  Really, you don't need any BI_DEV_TYPE's for non-core
kernel code - just a type that the kernel is guaranteed never to use
for any other bi_rec type.

Yes indeed.

BTW, I just thought of something different: some people want to keep data
stored in bi_recs for later use, after the initialization of the kernel. What
about a new tag to mark data that is to be copied and stored for later use?

Gr{oetje,eeting}s,

						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds


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