[DM388] How to enter deep sleep mode for dm388?

dark hou

Intellectual 940 points

Other Parts Discussed in Thread: DM388, DM385

Hi Ti:

We want to enable deep sleep mode for dm388.

We hope the power consumption can be within 30mA / 3.8V in deep sleep mode.

We test it on main board only.

No LCM and touch panel and others.

But we found the deep sleep mode seems useless.

Only kernel enter suspend mode.

The software version is RDK 380..

Hardware is dm388 linux platform.

The method we enter deep sleep mode is below.

1. echo 1 > /sys/kernel/debug/pm_debug/enable_deep_sleep

2. echo -n "mem" > /sys/power/state

The power consumption is 500 mA / 3.8V still

And the log is below.

Seems kernel is suspend.

And ti81xx_pm_suspend() is entered either.

Do you have any idea for it?

Or dm388 support deep sleep mode?

The log of entering sleep mode:

PM: Syncing filesystems ... done.
miis_motor: mmc driver sent 41, queue:2
mmc1: card 59b4 removed
Freezing user space processes ... (elapsed 0.01 seconds) done.
Freezing remaining freezable tasks ... (elapsed 0.03 seconds) done.
Suspending console(s) (use no_console_suspend to debug)

DarkHou

over 8 years ago

0 Dwarakesh Radhakrishnan over 8 years ago

Guru 13660 points

Hi Hou,

Have you made sure you have disabled all idle power domains with echo 1 > /sys/kernel/debug/pm_debug/turnoff_idle_powerdomain, before setting deepsleep ?

0 dark hou over 8 years ago in reply to Dwarakesh Radhakrishnan

Intellectual 940 points

Hi Dwarakesh:

I turn off idle power domains for it.

echo 1 > /sys/kernel/debug/pm_debug/turnoff_idle_powerdomains

The result is still the same. (500mA / 3.8V)

There are two domain can't enter off mode.

How can I solve it?

hdvpss_pwrdm did not enter off mode, current state = 3
isp_pwrdm did not enter off mode, current state = 3

Fail Log:

PM: Syncing filesystems ... done.
Freezing user space processes ... (elapsed 0.01 seconds) done.
Freezing remaining freezable tasks ... (elapsed 0.03 seconds) done.
Suspending console(s) (use no_console_suspend to debug)
PM: suspend of devices complete after 1.968 msecs
PM: late suspend of devices complete after 0.593 msecs
ti81xx_pm_suspend
hdvpss_pwrdm did not enter off mode, current state = 3
isp_pwrdm did not enter off mode, current state = 3
PM: early resume of devices complete after 0.529 msecs

DarkHou

0 Dwarakesh Radhakrishnan over 8 years ago in reply to dark hou

Guru 13660 points

Hi Hou,

The powerdomains seem to relate to M3 core. Can you for experiment, not load the ISS and HDVPSS firmwares(xem3) and check the power consumption ?

0 dark hou over 8 years ago in reply to Dwarakesh Radhakrishnan

Intellectual 940 points

Hi Dwarakesh :
If we remove ISS and HDVPSS firmware, the power consumption become from 500mA to 130ms (3.8V)
So it seems the system doesn't turn off for iss and hdvpss domain after entering sleep.

echo 1 > /sys/kernel/debug/pm_debug/turnoff_idle_powerdomains
echo -n "mem" > /sys/power/state
DarkHou

0 dark hou over 8 years ago in reply to dark hou

Intellectual 940 points

Hi Dwarakesh :
I see it need to turn off clock first if we want to power down some power domain.
But I didn't find anyone to turn off clock when kernel is suspend.
Do Ti has turn off relative power domain clock when kernel is suspend?

NOTE:If any of the power domains with switches(mentioned above) is active during suspend(any clock(s) running) then the power domain will not be powerd down i.e. the transition to OFF(0) state will not be successful, this will be reported during resume as shown below. e.g.if dsp clock was running then you will see following print:
gem_pwrdm did not enter OFF mode, current state = 3

processors.wiki.ti.com/.../TI81XX_PSP_PM_SUSPEND_RESUME_User_Guide
DarkHou

0 Dwarakesh Radhakrishnan over 8 years ago in reply to dark hou

Guru 13660 points

Hi Hou,

Thats right. I am checking how to clock down M3 cores.

0 dark hou over 8 years ago in reply to Dwarakesh Radhakrishnan

Intellectual 940 points

Hi Dwarakesh:

Do you have any good news about turn off M3 core clk?

Thanks~

DarkHou

0 Dwarakesh Radhakrishnan over 8 years ago in reply to dark hou

Guru 13660 points

Hi Hou,

Will check. Missed to check on this due to other work. Also will check with my team and reply ASAP.

0 Dwarakesh Radhakrishnan over 8 years ago in reply to Dwarakesh Radhakrishnan

Guru 13660 points

Hi Hou,

I checked with the team here. They say there is no readily available way to put off ISS clock. Here are few pointers on the different implementation tried by our team for low power:

1. Gate only ISS clocks from A8 ( Refer example for DSP : http://processors.wiki.ti.com/index.php/File:0001-ti814x-PM-driver-for-DSP-supporting-suspend-resume.patch.gz )
2. Implement low power in M3 and enable only one interrupt(message box) in M3 as wakeup and use it as interrupt source to wake M3 from A8, once A8 wakes up.
3. Disable the clock and power domain of M3. In that case firmware needs to be reloaded and there will be latency in starting the Video pipeline.

0 dark hou over 8 years ago in reply to Dwarakesh Radhakrishnan

Intellectual 940 points

Hi Dwarakesh :
Thanks you very much.

Does RDK380 or RDK390 support it now?
How can I implement low power in M3?

Or is it just a thinking for dm388?

1. Gate only ISS clocks from A8
2. Implement low power in M3 and enable only one interrupt(message box) in M3 as wakeup and use it as interrupt source to wake M3 from A8, once A8 wakes up.
3. Disable the clock and power domain of M3. In that case firmware needs to be reloaded and there will be latency in starting the Video pipeline.

DarkHou

0 Dwarakesh Radhakrishnan over 8 years ago in reply to dark hou

Guru 13660 points

Hi Hou,

These are suggestions and the solution is not readily available in both 3.8 and 3.9. For low power M3 refer to ARM spec ( infocenter.arm.com/.../index.jsp ).

0 dark hou over 8 years ago in reply to Dwarakesh Radhakrishnan

Intellectual 940 points

Hi Dwarakesh:
Because we see the report in TI web site, dm385 is 107mW for deep sleep mode.
It looks like you have solution for it already.
And we like to know how can we get such low power consumption for it?

Can you tell us which version of SW do you test for DM385_PowerSpreadSheet_Ver1_00?

Ref:
processors.wiki.ti.com/.../File:DM385_PowerSpreadSheet_Ver1_00_Release.zip.

DarkHou

0 Dwarakesh Radhakrishnan over 8 years ago in reply to dark hou

Guru 13660 points

Hi Hou,

I have suggested solution for deep sleep(low power) and the suggestions does not guarantee the wattage mentioned in the Spread Sheet. These were tried by us for our low power use case and our solutions cannot assure/match what TI has provided. Need to check with TI people on the clarification w.r.t Spread Sheet. I hope someone from TI can comment on this. If TI does not reply here, we can internally place this query to TI and get back.

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[DM388] How to enter deep sleep mode for dm388?