can someone explain this CONFIG_COMMANDS, CFG_CMD thing?

can someone explain this CONFIG_COMMANDS, CFG_CMD thing?

[Robert P. J. Day]

  i'm looking at some of the stuff sascha commented on earlier, like:

$ grep -r CONFIG_MII drivers
drivers/net/Makefile:obj-$(CONFIG_MIIPHY)			+= miiphy.o
drivers/net/at91_ether.c:#if defined(CONFIG_MII) || (CONFIG_COMMANDS & CFG_CMD_MII)
drivers/net/at91_ether.c:#endif	/* defined(CONFIG_MII) || (CONFIG_COMMANDS & CFG_CMD_MII) */
drivers/net/at91_ether.c:#if defined(CONFIG_MII) || (CONFIG_COMMANDS & CFG_CMD_MII)
$

and i'd like to clarify what any of that is *supposed* to mean.

  first, what means "CONFIG_COMMANDS"?  that is, in the sense that
you're *bitwise* or'ing it with something else?  is that supposed to
be a test that a command has been selected for inclusion?  surely
there's a cleaner way to do that.

  and what would the difference be between CONFIG_MII and CFG_CMD_MII?
as i read it (and i could be totally out to lunch), something like
CONFIG_MII would be selecting a particular *feature* to build in,
while CFG_CMD_MII would be selecting the actual "mii" command, is that
it?

  but should those two selections be independently selectable?
possibly -- i can imagine an argument that that should be true.  but
in a perfect world, how should all this be done?  personally, i can
imagine selecting *features* one by one and, for each feature,
selecting any of the relevant and associated commands.

  so (as a random example), i might first select MII support with
CONFIG_MII, then separately select to include the "mii" command with
CONFIG_CMD_MII.  and commands should be Kconfig dependent on their
associated feature, so that there would be no need to test

 #if defined(CONFIG_MII) && defined(CONFIG_CMD_MII)

it would be sufficient to test

 #if defined(CONFIG_CMD_MII)

or am i completely misreading what should be happening here?

rday
--

========================================================================
Robert P. J. Day                               Waterloo, Ontario, CANADA

            Linux Consulting, Training and Kernel Pedantry.

Web page:                                          http://crashcourse.ca
Twitter:                                       http://twitter.com/rpjday
========================================================================

_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox

Re: can someone explain this CONFIG_COMMANDS, CFG_CMD thing?

[Sascha Hauer]

On Mon, Dec 21, 2009 at 09:56:07AM -0500, Robert P. J. Day wrote:
> 
>   i'm looking at some of the stuff sascha commented on earlier, like:
> 
> $ grep -r CONFIG_MII drivers
> drivers/net/Makefile:obj-$(CONFIG_MIIPHY)			+= miiphy.o
> drivers/net/at91_ether.c:#if defined(CONFIG_MII) || (CONFIG_COMMANDS & CFG_CMD_MII)
> drivers/net/at91_ether.c:#endif	/* defined(CONFIG_MII) || (CONFIG_COMMANDS & CFG_CMD_MII) */
> drivers/net/at91_ether.c:#if defined(CONFIG_MII) || (CONFIG_COMMANDS & CFG_CMD_MII)
> $
> 
> and i'd like to clarify what any of that is *supposed* to mean.
> 
>   first, what means "CONFIG_COMMANDS"?  that is, in the sense that
> you're *bitwise* or'ing it with something else?  is that supposed to
> be a test that a command has been selected for inclusion?  surely
> there's a cleaner way to do that.

Forget about CONFIG_COMMANDS. This is from old U-Boot and is a bitmask
for the available commands. CFG_CMD_MII was one bit of this command
mask. Someday they realized that they want to support more than 32
commands and got rid of it.

The parts you are referring to should simply be

#if defined(CONFIG_MII)

Hm, looking closer at it this part of the at91 ethernet driver is
outdated. Compare to the other ethernet drivers to get an idea how phys
are handled now. Maybe I'll fix this after christmas.

Sascha


-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |

_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox