ibm4xx_quiesce_eth?

[Josh Boyer]

On Thu, 10 Jan 2008 13:38:12 -0500
Sean MacLennan <smaclennan at pikatech.com> wrote:

> What exactly does this function do?
> 
>     /* Quiesce the MAL and EMAC(s) since PIBS/OpenBIOS don't
>      * do this for us
>      */
> 
> On the taco, with the 440EP, it doesn't seem to make any difference if I 
> call this or not. Since I am using u-boot, is it not needed?

There are firmwares that do not reset the EMAC and MAL before passing
control to the client program (Linux in our case).  This can cause
weird things to happen, like spurious interrupts or DMAs from the
hardware overwriting kernel memory.  So we quiesce the hardware really
early on those.

I don't believe U-Boot has that problem.  If it does, it should be
fixed :)

josh