[U-Boot] [PATCH 1/4] net: ll_temac: Add LL TEMAC driver to u-boot

Michal Simek monstr at monstr.eu
Wed Mar 28 09:53:54 CEST 2012

Hi Joe,

>> Stephan Linz wrote:
>>> Xilinx LocalLink Tri-Mode Ether MAC driver can be
>>> used by Xilinx Microblaze or Xilinx ppc405/440 in
>>> SDMA and FIFO mode. DCR or XPS bus can be used.
>> Joe, Wolfgang: I don't agree with this driver because it is doing the same
>> things as my origin
>> version but on 800 lines instead of 1860lines. The next thing is that plb
>> bus on Xilinx fpgas
>> is getting obsolete.
> Are you meaning that you already have a driver in u-boot that works on
> this hardware or do you mean the original version somewhere else, like
> Linux?

There is really long history about this u-boot driver. The origin version for ppc was sent to mailing list
April 26, 2008 by Yoshio Kashiwagi. I have tried to add it to mainline several times
and my latest attempts end with result that I didn't want to follow u-boot coding style because
of ppc/microblaze differences (not using offset with structure because of ppc/microblaze differences - dcr/plb access).
That driver has 800 lines.
Based on this strict rule I decided not to continue to push this driver to mainline
because it is just a lot of work to change it and especially test it. My origin driver is used by many our customers
on microblaze and ppc and none reported any problem with it.

After this Stephan decided to change it to be acceptable to mainline submission.

> As for plb being near obsolescence, are you recommending a change to
> the driver to drop support for that bus option? Or do you mean for
> that reason the driver itself should be omitted?

should be obsolete in a year or so and if you add it to mainline it will be there
but in 2013 there will be minimal number of users for it.

>> I am not going to add it to my microblaze custodian tree.
>> If you like this patch please add it to u-boot-net tree or directly to
>> mainline.
> I was actually going to recommend that it go through the microblaze
> branch if it is primarily for microblaze targets.  If you don't want
> it, then I think Stephan needs to work to convince you by making
> revisions.

None can convince me that 1860 code lines which fulfill all u-boot rules
is better than origin well tested 800 code lines (and commercially used)
which break one u-boot rule.
I agree with rules but none can expect that I will assist and help to add
it to mainline. I don't want to have responsibility for that.

BTW: Target is also ppc because there is DCR support.


Michal Simek, Ing. (M.Eng)
w: www.monstr.eu p: +42-0-721842854
Maintainer of Linux kernel 2.6 Microblaze Linux - http://www.monstr.eu/fdt/
Microblaze U-BOOT custodian

More information about the U-Boot mailing list