[PATCH 5/8] ARM: PXA: Z2: Add poweroff function

[Vasily Khoruzhick]

On Saturday 12 March 2011 00:16:57 Marek Vasut wrote:
> On Friday 11 March 2011 23:12:40 Vasily Khoruzhick wrote:
> > On Saturday 12 March 2011 00:08:58 Marek Vasut wrote:
> > > On Friday 11 March 2011 22:53:11 Vasily Khoruzhick wrote:
> > > > On Friday 11 March 2011 23:39:03 Marek Vasut wrote:
> > > > > On Friday 11 March 2011 11:23:40 Vasily Khoruzhick wrote:
> > > > > > Signed-off-by: Vasily Khoruzhick <anarsoul at gmail.com>
> > > > > 
> > > > > This looks bogus to me as you cannot power down the thing. Besides,
> > > > > where do you resume to from this so-called "powerdown" ? Since the
> > > > > bootloader will consider it as a legitimate deepsleep resume.
> > > > 
> > > > It eats only 0.7mA in deepsleep, but 6.7mA in sleep (PXA2xx has 2
> > > > sleep modes), so deepsleep is pretty close to poweroff.
> > > 
> > > So the power to the CPU is actually cut? It isn't, right ?
> > 
> > It isn't. But looks like power to memory is cut. But stock bootloader
> > puts it in deepsleep to save battery.
> 
> Power to memory is cut? How come? You mean rather the refresh is disabled,
> right ? But anyway, isn't the ram put into self-refresh ?

Well, it looks like memory content is not preserved, or something wrong with 
bootloader. Anyway, it does not resume after deepsleep for some reason, I 
can't check better, as I have no JTAG. Maybe you can investigate this problem?
 
> > > Mine (I use mainline uboot) doesn't.
> > 
> > Can you re-check it?
> 
> Check what ? Yes I can ...

No need, I understand how it works, PSPR is null, so after u-boot loads PSPR 
to pc it performs 'soft reset' (jumps to 0x0, to begin of NOR flash), RCSR 
bits are already cleared, so it just boots kernel.

Regards
Vasily