[U-Boot] [PATCH 01/27] net: new utility functions for working with enetaddr's

[Mike Frysinger]

On Monday 16 February 2009 19:13:31 Wolfgang Denk wrote:
> Dear Mike,
>
> In message <200902161900.49096.vapier at gentoo.org> you wrote:
> > > Hm... Linux has a printk() format specifier for MAC addresses. Sounds
> > > like a clever idea to me. Maybe we should borrow that code?
> >
> > it does eh ?  that certainly sounds a lot better than str_enetaddr() as
> > every place i changed to use it was in a printf() string.  where in the
> > kernel is that code ?  i looked in lib/vsprintf.c but couldnt find it.
>
> But it is in lib/vsprintf.c:

apparently it's new to 2.6.29 ... i'm actively working/looking at 2.6.28.x 
which doesnt have 'M'.

>  ...
>  644 /*
>  645  * Show a '%p' thing.  A kernel extension is that the '%p' is followed
>  646  * by an extra set of alphanumeric characters that are extended format
>  647  * specifiers.
>  648  *
>  649  * Right now we handle:
>  650  *
>  651  * - 'F' For symbolic function descriptor pointers
>  652  * - 'S' For symbolic direct pointers
>  653  * - 'R' For a struct resource pointer, it prints the range of
>  654  *       addresses (not the name nor the flags)
>  655  * - 'M' For a 6-byte MAC address, it prints the address in the
>  656  *       usual colon-separated hex notation
>  657  * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
> (dot-separated 658  *       decimal for v4 and colon separated
> network-order 16 bit hex for v6) 659  * - 'i' [46] for 'raw' IPv4/IPv6
> addresses, IPv6 omits the colons, IPv4 is 660  *       currently the same
>  ...
>
> So it's actually printk("%pM", ...);

so do you want to go the %pM route (to make u-boot/linux code sharing easier) 
or move over only %M ?
-mike