CONFIG_PM_DEBUG=y

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1

Howdy:

I got the latest pm kernel from Kevin Hilman's git tree, used the
omap3_beagle_defconfig, manually changed it to CONFIG_PM_DEBUG=y, did
a make menuconfig to confirm that it was indeed changed in there, made
my uImage.bin, copied it to an SD card, booted up off of the SD card,
and when I look at the / directory, there is no /debug directory, let
alone a /debug/pm_debug (and all the hopefully cool contents thereof).

Is there something special I need in terms of a ramdisk.gz file from
somewhere, or a special bootargs variable, or compilation step I'm
missing?

Thanks,
Bill Bock
DFT

2

You need to mount the debug file system. Read:

http://elinux.org/OMAP_Power_Management#Advanced_features_for_PM_developers_and_power_users

Cameron.

PS Those instructions should probably be mentioned further up the page.

3

Cameron:

Thanks, that was definitely a problem. It pointed me to a bigger
(prior)
problem in that I wasn't including the debugfs in the kernel. I had
thought
that having "PM_DEBUG=y" in the .config was enough, but after
searching
I saw the CONFIG_DEBUG_FS, set it, and I was able to mount the
debugfs
on a /debug directory I created at the root level (/).

Unfortunately, even after turning on a bunch of debug-related config
options,
I only have all the power domains (ex: mpu_pwrdm), registers, count,
and
time. I'm missing all the cool things like 'wakeup_timer_seconds',
'sleep_while_idle', 'enable_off_mode', and 'voltage_off_while_idle'.
Do I
just need to make another sweep through the .config file and turn on a
few
more options or am I missing something else when it comes to these
things?

Thanks,
Bill Bock
DFT

4

IIRC they just worked for me, but I was using one of Robert Nelson's
defconfigs. I vaguely recall someone saying to not use omap3_beagle_defconfig.

Make sure you cloned the pm branch of that repo. There is more than one branch
in there, and I spent a confused hour once trying to work out why things were
missing before realising I'd cloned the wrong one.

Good luck,

Cameron.

5

Howdy:

I suspect using the wrong branch was my problem. I got the 'pm-off'
branch
but before trying to use it it was suggested I try a TI kernel image.
This worked.
I don't have access to things like 'count', 'time', or 'registers',
but things are
mostly working and I'm progressing.

I might go back to the pm branch later on now that I have a slightly
better
understanding of the importance of the .config (as in: very).

Thanks,
Bill Bock
DFT