MPC8272 FCC2 MDIO on Port D and FS_ENET

[NM]

Thanks Scott,
I do boot from U-BOOT, via Ethernet, but I'd never set the MDIO/MDC in U-BOOT. Actually, looking at the u-boot 's MPC8260ADS.h now, it is still setting the default 8272ADS boards' PC18/19 for MDC/MDIO - and my unit is using PD23/29.
I guess U-BOOT is probably working (for me) since it probably defaults to the defaults of PHY and maybe not checking for PHY errors???

I guess, it is probably worthwhile having the MDIO/MDC pins also  set up explicitly in mpc8272_ads_pins as opposed to relying on the boot loader.







Scott Wood <scottwood at freescale.com> wrote: NM wrote:
> My problem is solved now after probing the lines, MDC was not showing 
> any activity.
> So, after explicitly setting the PD23 (MDC) to : OUTPUT/GPIO in 
> mpc8272_ads_pins and  it worked in
> 
> I'd previously thought about that, but I was sure that this was being 
> taken care of, but now that I'm thinking of it, I'm questioning my belief. 
> I think in the fs_enet/mii-bitbang.c: mdio_dir(..) it is supposed to 
> take care of this.

No, the mdc pin is static; only bits which need to be changed 
dynamically are dealt with in mii-bitbang.c.  Either the firmware or the 
platform code should set up static pins.

> But why I had to explictly set it initially beats me. 
> I wonder how this works in standard distribution.

It's probably set up by u-boot normally, at least if you boot from ethernet.

-Scott


       
---------------------------------
Looking for the perfect gift? Give the gift of Flickr!
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://ozlabs.org/pipermail/linuxppc-embedded/attachments/20080211/b3475c2c/attachment.htm