unhandled ethernet wakeup interrupt in 405 ethernet driver

Hi,

I noticed a networks problem with some of our 405EP platforms (u-boot
config: PLU405). When doing tftp u-boot runs into an endless interrupt loop of the ethernet wakeup interrupt (VECNUM_EWU0).

So why is the wakeup interrupt enabled in 405gp_enet.c in general? The interrupt handler enetInt() does not care about this interrupt source at all. So when it occurs we end up in an interrupt loop. I found no hint about how to reset this interrupt in the 405EP manual.

When I do not install a handler on the wakeup interrupt source (EWU0) everything is fine. This is my current workaround.

The current 405 linux ethernet driver also does not attach to this interrupt.

I am astonished about two things:

1) The installation of the enetInt() handler for the wakeup interrupt is only done for 405EP platforms in ppc_4xx_eth_initialize():

#if defined(CONFIG_405EP)
			/* 405EP has one EWU interrupt */
			irq_install_handler (VECNUM_EWU0,
					     (interrupt_handler_t *) enetInt,
					     dev);

#endif

But it is not done for 405EP platforms in ppc_4xx_eth_init():

#if !defined(CONFIG_405EP)
		/* 405EP has one EWU interrupt */
		irq_install_handler (VECNUM_EWU0 + (hw_p->devnum * 2),
				     (interrupt_handler_t *) enetInt, dev);

#endif

This seems to be strange at all.

I suppose that no one is using the wakeup mechanism and so I propose to completely remove the wakeup stuff!

2) Why the hell do we get ethernet wakeup interrupts on some of our 405EP boards :-(

So can we get rid of installing a wakeup interrupt that even does not handle the interrupt? If yes I will submit a patch.

Matthias

-------------------------------------------------------------------------

                             _/_/_/_/   Matthias Fuchs
                            _/_/_/_/   Dipl.-Ing.
                           _/_/_/_/   matthias.fuchs at esd-electronics.com

       _/_/_/   _/_/_/_/_/_/_/      esd electronic system design gmbh
     _/   _/  _/             _/    Vahrenwalder Str. 207
    _/   _/    _/_/_/   _/   _/   D-30165 Hannover
    _/             _/  _/   _/   Phone: +49-511-37298-0
     _/_/_/_/_/_/_/   _/_/_/    Fax:   +49-511-37298-68

-------------------------------------------------------------------------

Hi,

I came to the conslusion that the ethernet wakeup interupt should not be touched by u-boot and the code can be removed.

Here is my patch that fixes cpu/ppc4xx/405gp_enet.c.

Here is the changelog entry:

* Patch by Matthias Fuchs, 10 May 2005:
Do not attach to ethernet wakeup interrupt in 405gp_enet.c

Does anything speak against this patch? I do not think so :-)

Matthias

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