Subject: Re: Cannot wake-up from standby with MPC8313

From: Scott Wood <[email-masked]>
Date: Mon, 16 Jan 2012 14:22:09 -0600

On 01/13/2012 08:13 AM, Norbert van Bolhuis wrote:
> I dumped SIPNR/SIMSR and uart IIR/EIR (since console triggers wake-up)
> but they do not change just before entering standby (via
> mpc6xx_enter_standby
> which omits setting MSR_POW). uart IRQ is always enabled, unmasked and
> not pending.
> 
> I tried to log to physical memory to see what's going on whenever the
> board fails to wake-up.
> (I can examine physical memory after CPU is stuck in sleep, by connecting
>  a JTAG debugger, start u-boot and stop after DDR2 SDRAM ctrl is
>  re-configured)

Are you sure this isn't going to disturb anything?  Why does U-Boot need
to be involved, and the SDRAM reconfigured?

> It looks like an interupt does occur, but do_IRQ seems to be stuck
> in ppc_md.get_irq=ipic_get_irq where it reads SIVCR.

Stuck as in the load never completes, or as in ipic_get_irq() gets
called repeatedly?  If the latter, what value is it reading out?  Is the
interrupt pending in SIPNR at this point?

-Scott