Hi Niklas,
On Thu, Jun 29, 2017 at 5:18 PM, Niklas Söderlund
<niklas.soderlund@xxxxxxxxxxxx> wrote:
> On 2017-06-29 15:25:15 +0200, Geert Uytterhoeven wrote:
>> During PSCI system suspend, R-Car Gen3 SoCs are powered down, and their
>> clock register state is lost. Note that as the boot loader skips most
>> initialization after resume, clock register state differs from the state
>> encountered during normal system boot, too.
>>
>> Hence after s2ram, some operations may fail because module clocks are
>> disabled, while drivers expect them to be still enabled. E.g. EtherAVB
>> fails when Wake-on-LAN has been enabled using "ethtool -s eth0 wol g":
>>
>> ravb e6800000.ethernet eth0: failed to switch device to config mode
>> ravb e6800000.ethernet eth0: device will be stopped after h/w processes are done.
>> ravb e6800000.ethernet eth0: failed to switch device to config
>> PM: Device e6800000.ethernet failed to resume: error -110
>>
>> In addition, some clocks that were disabled by clk_disable_unused() may
>> have been re-enabled, wasting power.
>>
>> This RFC is a second attempt to fix this issue by restoring clock registers
>> during system resume.
>> This has been tested on Salvator-X with R-Car H3 ES1.0 and M3-W ES1.0.
>> On Salvator-XS with R-Car H3 ES2.0, EtherAVB restarts after system resume,
>> but NFS fails with "server not responding", probably not due to a clock
>> issue.
>
> I tested this series using this setup:
>
> - Base latest renesas-drivers, 710def1a48c7bc9d ("of_mdio: Fix broken
> PHY IRQ in case of probe deferral"). This branch also includes the
> RAVB WoL patches.
>
> - Salvator-X H3 ES1.0
>
> - The arm64 defconfig.
>
> The test procedure I used:
>
> arm64 ~/shared/deep-sleep # cat sleep.sh
> #!/bin/bash
>
> ethtool -s eth0 wol g
>
> echo disabled > /sys/devices/platform/soc/e6800000.ethernet/power/wakeup
>
> echo 0 > /sys/module/printk/parameters/console_suspend
>
> i2cset -f -y 7 0x30 0x20 0x0F
>
> echo "Flip Switch"
> read -n 1
>
> echo mem > /sys/power/state
Looks good.
> And for me the NFS root came up OK after flipping switch back. I wonder
> what is different in our test procedures. I would like to provide my
> tested-by tag but I first want to figure out why NFS (or maybe the whole
> net interface?) don't work for you after resume.
Sorry for the confusion: NFS fails only on Salvator-XS H3 ES2.0.
It works fine on Salvator-X H3 ES1.0 and M3-W ES1.0.
> I also know you reported an IRQ storm when resuming using WoL which I in
> over 1000 suspend/resume cycles never have been able to reproduce. Maybe
> my test environment or procedure is to kind and/or something is falling
> thru the cracks :-( Do you notice any difference in test procedure or
> console printouts?
I saw the IRQ storm only once.
Thanks for testing!
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
