Neo1973 suspend/resume

Harald Welte laforge at
Wed Feb 21 10:22:02 CET 2007

On Wed, Feb 21, 2007 at 01:03:48AM +0000, Ben Dooks wrote:
> > If I then press the button and generate the wakeup-irq, the backlight
> > becomes bright for something like estimated 250ms, but the content
> > slowly fades out (no LCM refresh happening) and n the system
> > seems to power-off again, since the JTAG adaptor continues to issue
> What powers the LCD up? could we have resumed but failed to load
> the NAND block properly?

the LCM power-up is done via GPIO and usually happens in
board_late_init().  Now that I think more

> > > Error:   arm7_9_common.c:561 arm7_9_execute_sys_speed(): timeout waiting for SYSCOMP & DBGACK, last DBG_STATUS: 0
> > 
> > The CPU does not want to halt on JTAG request, at least not if that
> > request is issued before the wake-up event happens.
> > 
> > Do you have any experience in using JTAG to single-step the resume
> > procedure?
> No, I enabled the UART early on and simply wrote to the serial port
> as starting up.
> There is an entirely obvious bug in my code btw, 
> it reads GSTATUS2 at 0x560000B4 twice... it should be GSTATUS3
> at 0x560000B8. Patch is up as uboot-neo1973-resume4.patch
> If this fixes it, then sorry for the mistake

ok, I'm testing resume5.patch later on.

> > 2) As you know, current hardware doesn't care about the PWREN output and
> > thus leaves VDDi/VDDiarm/VDDi_*PLL enabled while in Power_off.  Can this
> > be the reason why resume isn't working as expected?
> This one I'm not sure I can test anywhere. All our designs have
> the correct use of PWREN to control the power into the pll/cpu power
> pins. There may be an SMDK board where we can expirment with this.
> I assume the wakeup login resets the core, but maybe it requires the
> power up to initiate the core reset to get the system back into working
> order.

Yes, that might very well be possible.  Since PWREN is not even on a
test pad, I also can't try to check whether it correctly switches off
and on again.

> > Any other ideas?
> have you tried the same fixes for the qt2410?
no, haven't touched that board in ages.  will try if resume5.patch
doesn't work at all on the GTA01.

- Harald Welte <laforge at>         
Software for the world's first truly open Free Software mobile phone

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