On 6/10/20 3:02 PM, Krzysztof Kozlowski wrote:
On Wed, Jun 10, 2020 at 02:18:12PM +0100, Lukasz Luba wrote:
Hi Krzysztof, Bartek,
I recall that you have been working on some cpuidle code for Exynos(4?).
I have a question regarding CPUIdle driver for Odroid XU4.
I use the board with LISA tests for EAS, but missing at
least idle state 0 cause errors (please see the log below).
Currently the system does not report any idle driver and the state 0
is missing in: /sys/devices/system/cpu/cpu0/cpuidle/state0/
The state 0 long time ago was WFI. It was kind of meaningless so it it
was dropped.
I see.
I am using driver CONFIG_ARM_BIG_LITTLE_CPUIDLE but the
boot stops silently while trying to init the cpu idle devices in there.
I carry on with a workaround that just removes idle state[1] and set
state_count=1 in the big and little structures.
Try earlyprintk.
I've tried and printed some dbg in that driver and just simply
dropped the deeper idle and system runs. Idle driver account properly
the residency time for this WFI in the state0 dir. That's enough for
what I need in testing - accounting wfi from that dir location.
In general, the big-little cpuidle driver should work... or rather: long
time ago it was working. It requires proper support from early stages
(BL1, secure monitor) but this should be already in standard Odroid.
I just saw there:
/* Start at index 1, index 0 standard WFI */
so maybe it was not updated properly to removal of WFI?
I think no one uses this driver so it might be not well tested and not
that useful.
OK, good to know, I just found this driver by compatibility string and
thought it could be used.
Thank you Krzysztof for you instant response.
Regards,
Lukasz
Best regards,
Krzysztof
