N900 sleep mode (in 4.5-rc0, if that matters)

Tony Lindgren tony at atomide.com
Tue Jan 26 09:25:28 PST 2016


* Pavel Machek <pavel at ucw.cz> [160126 06:01]:
> 
> It seems like I have rather lot of blocking bits:
> 
> 00001fff 48005020 (fa005020) cm_idlest_per blocking bits: 0007e000

Looks like most of these are for GPIO banks, that's OK those get saved
and restored in the idle loop.

Here bit 18 UART4 is a mystery though.. It's uart4 on 36xx but reserved
on 34xx. I do have that too on my n900, but it's hitting off mode with
v4.4.

> ffdffe8d 48004a20 (fa004a20) cm_idlest1_core blocking bits: 00200072
> 0000000d 48004a28 (fa004a28) cm_idlest3_core
> 
> cm_idlest1_core changes periodicall often, to 00218072. The rest seems
> constant.

For cm_idlest1_core 42 is the answer.. Here you have bits 4 and 5
blocking which is for OTG and it's PHY. That's a known issue with
musb and setting pm_runtime_irq_safe() on the MUSB parent.

If you do rmmod omap2430 and phy-twl4030usb chances are the LEDs will
start going off assuming the McSPI bit goes low with WLAN idling.

Looks like we have some regression with v4.5-rc1 where n900 is not
hitting deeper idle states though. I'll run git bisect between
v4.4..v4.5-rc1.

Regards,

Tony



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