Re: [PATCH] arm64: dts: rockchip: Fix rk3399-gru-* s2r (pinctrl hogs, wifi reset)

[Doug Anderson]

Hi,

On Tue, Mar 6, 2018 at 10:58 AM, Marc Zyngier <marc.zyngier@xxxxxxx> wrote:
> On 06/03/18 18:49, Heiko StÃbner wrote:
>> Am Dienstag, 6. MÃrz 2018, 19:15:18 CET schrieb Marc Zyngier:
>>> Hi Doug,
>>>
>>> On 06/03/18 18:00, Doug Anderson wrote:
>>>> Hi,
>>>>
>>>> On Tue, Mar 6, 2018 at 3:58 AM, Marc Zyngier <marc.zyngier@xxxxxxx> wrote:
>>>>> Hi all,
>>>>>
>>>>> On 01/03/18 08:43, Heiko StÃbner wrote:
>>>>>> Am Dienstag, 27. Februar 2018, 21:47:11 CET schrieb Douglas Anderson:
>>>>>>> Back in the early days when gru devices were still under development
>>>>>>> we found an issue where the WiFi reset line needed to be configured as
>>>>>>> early as possible during the boot process to avoid the WiFi module
>>>>>>> being in a bad state.
>>>>>>>
>>>>>>> We found that the way to get the kernel to do this in the earliest
>>>>>>> possible place was to configure this line in the pinctrl hogs, so
>>>>>>> that's what we did.  For some history here you can see
>>>>>>> <http://crosreview.com/368770>.  After the time that change landed in
>>>>>>> the kernel, we landed a firmware change to configure this line even
>>>>>>> earlier.  See <http://crosreview.com/399919>.  However, even after the
>>>>>>> firmware change landed we kept the kernel change to deal with the fact
>>>>>>> that some people working on devices might take a little while to
>>>>>>> update their firmware.
>>>>>>>
>>>>>>> At this there are definitely zero devices out in the wild that have
>>>>>>> firmware without the fix in it.  Specifically looking in the firmware
>>>>>>> branch several critically important fixes for memory stability landed
>>>>>>> after the patch in coreboot and I know we didn't ship without those.
>>>>>>> Thus, by now, everyone should have the new firmware and it's safe to
>>>>>>> not have the kernel set this up in a pinctrl hog.
>>>>>>>
>>>>>>> Historically, even though it wasn't needed to have this in a pinctrl
>>>>>>> hog, we still kept it since it didn't hurt.  Pinctrl would apply the
>>>>>>> default hog at bootup and then would never touch things again.  That
>>>>>>> all changed with commit 981ed1bfbc6c ("pinctrl: Really force states
>>>>>>> during suspend/resume").  After that commit then we'll re-apply the
>>>>>>> default hog at resume time and that can screw up the reset state of
>>>>>>> WiFi.  ...and on rk3399 if you touch a device on PCIe in the wrong way
>>>>>>> then the whole system can go haywire.  That's what was happening.
>>>>>>> Specifically you'd resume a rk3399-gru-* device and it would mostly
>>>>>>> resume, then would crash with some crazy weird crash.
>>>>>>>
>>>>>>> One could say, perhaps, that the recent pinctrl change was at fault
>>>>>>> (and should be fixed) since it changed behavior.  ...but that's not
>>>>>>> really true.  The device tree for rk3399-gru is really to blame.
>>>>>>> Specifically since the pinctrl is defined in the hog and not in the
>>>>>>> "wlan-pd-n" node then the actual user of this pin doesn't have a
>>>>>>> pinctrl entry for it.  That's bad.
>>>>>>>
>>>>>>> Let's fix our problems by just moving the control of
>>>>>>> "wlan_module_reset_l pinctrl" out of the hog and put them in the
>>>>>>> proper place.
>>>>>>>
>>>>>>> NOTE: in theory, I think it should actually be possible to have a pin
>>>>>>> controlled _both_ by the hog and by an actual device.  Once the device
>>>>>>> claims the pin I think the hog is supposed to let go.  I'm not 100%
>>>>>>> sure that this works and in any case this solution would be more
>>>>>>> complex than is necessary.
>>>>>>>
>>>>>>> Reported-by: Marc Zyngier <marc.zyngier@xxxxxxx>
>>>>>>> Fixes: 48f4d9796d99 ("arm64: dts: rockchip: add Gru/Kevin DTS")
>>>>>>> Fixes: 981ed1bfbc6c ("pinctrl: Really force states during
>>>>>>> suspend/resume")
>>>>>>> Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
>>>>>>
>>>>>> applied as fix for 4.16 with the 2 Tested-tags
>>>>>
>>>>> Sorry to rain on everyone's parade, but further testing shows that this
>>>>> patch may not be enough to restore a reliable s2r. My initial testing
>>>>> did show that we were resuming without the VOP errors, but there seem to
>>>>> be further issues (I'm loosing the keyboard and the trackpad after
>>>>> resume on Kevin).
>>>>>
>>>>> Applying my initial hack makes it work again. I suspect that there are
>>>>> more hog pins that need tweaking, but I'm a bit out of my depth here.
>>>>
>>>> Are you positive you weren't just wearing your lucky hat when you
>>>> tested your patch and then took it off when you tested mine?  As far
>>>
>>> So far, I seem to have a 100% success rate in resuming with my silly
>>> hack, whist your DT patch alone only gives me a 50% rate at best.
>>>
>>>> as I can see the only hogs left on kevin are:
>>>>   &ap_pwroff      /* AP will auto-assert this when in S3 */
>>>>   &clk_32k        /* This pin is always 32k on gru boards */
>>>>
>>>> Those map to:
>>>>   ap_pwroff: ap-pwroff {
>>>>
>>>>      rockchip,pins = <1 5 RK_FUNC_1 &pcfg_pull_none>;
>>>>
>>>>   };
>>>>
>>>>   clk_32k: clk-32k {
>>>>
>>>>     rockchip,pins = <0 0 RK_FUNC_2 &pcfg_pull_none>;
>>>>
>>>>   };
>>>>
>>>> So I added some printouts at suspend/resume time.  Specifically I set
>>>> a boolean to "true" for the duration rockchip_pinctrl_suspend() and
>>>> rockchip_pinctrl_resume() and this turned on a printout in
>>>> rockchip_set_mux().  My printout looked like this (yeah, I know it's a
>>>> whitespace-damaged patch just to show what I'm doing):
>>>>
>>>> +       regmap_read(regmap, reg, &before);
>>>>
>>>>         data = (mask << (bit + 16));
>>>>         rmask = data | (data >> 16);
>>>>         data |= (mux & mask) << bit;
>>>>         ret = regmap_update_bits(regmap, reg, rmask, data);
>>>>
>>>> +       regmap_read(regmap, reg, &after);
>>>> +
>>>> +       if (DOUG) {
>>>> +               dev_info(info->dev,
>>>> +                        "setting mux of GPIO%d-%d to %d;
>>>> %#010x=>%#010x\n", +                        bank->bank_num, pin, mux,
>>>> reg, before, after); +       }
>>>>
>>>> ...and a similar one in rockchip_set_pull().  That showed this at resume
>>>> time:
>>>>
>>>> [   62.284427] rockchip-pinctrl pinctrl: setting mux of GPIO1-5 to 1;
>>>> 0x00009400=>0x00009400
>>>> [   62.294423] rockchip-pinctrl pinctrl: setting pull of GPIO1-5;
>>>> 0x000041aa=>0x000041aa
>>>> [   62.303343] rockchip-pinctrl pinctrl: setting mux of GPIO0-0 to 2;
>>>> 0x00005002=>0x00005002
>>>> [   62.313240] rockchip-pinctrl pinctrl: setting pull of GPIO0-0;
>>>> 0x00000ddc=>0x00000ddc
>>>> [
>>>>
>>>> Said another way: pinmux and pull isn't actually changing due to the
>>>> hogs.  We can see if something else could be changing, but I'd really
>>>> want to be sure you're certain that the hogs are causing you
>>>> problems...
>>>
>>> I cannot say for sure that the hogs are the issue. But I thought that
>>> they were the only pins affected by 981ed1bfbc6c... If this patch can
>>> affect other pins, then I'm probably barking up the wrong tree.
>>
>> On Kevin I see something like
>>
>> [   60.764129] cros-ec-spi spi2.0: spi transfer failed: -108
>> [   60.764132] cros-ec-spi spi2.0: cs-deassert spi transfer failed: -108
>> [   60.764136] cros-ec-spi spi2.0: Command xfer error (err:-108)
>> [   60.764365] cros-ec-spi spi2.0: spi transfer failed: -108
>> [   60.764368] cros-ec-spi spi2.0: cs-deassert spi transfer failed: -108
>> [   60.764371] cros-ec-spi spi2.0: Command xfer error (err:-108)
>>
>> on resume with my current for-next. So maybe your hack just
>> happened to change some timing during resume?
>
> No, I carry yet another patch to make that one work[1].
>
>> Suspend/Resume also disconnects my usb-ethernet, making me lose my
>> nfsroot, so I can test this once every boot only.

Yeah, it kills usb-ethernet for me too.  ...so I can suspend/resume
once and then the next suspend fails with a bunch of usb errors.  This
is based on your "hack/kevin-4.16", which looks like:

e7934b797f4b (HEAD, linux_arm-platforms/hack/kevin-4.16) arm64: dts:
rockchip: Fix rk3399-gru-* s2r (pinctrl hogs, wifi reset)
9b9988414f44 irqchip/gic-v3: Allow LPIs to be disabled from the command line
d5e06c686858 iommu/rockchip: Perform a reset on shutdown
55b36a99626f drm/rockchip: Don't use spin_lock_irqsave in interrupt context
7d72d7e57c2c drm/rockchip: Do not use memcpy for MMIO addresses
236afcd0425c drm/rockchip: Clear all interrupts before requesting the IRQ
31608ae0d3fc arm64: Enable dynamic sched_domain flag setting
1b255643cdc3 drivers/base/arch_topology: Dynamic sched_domain flag detection
2caca1b31f89 arm64: rk3399: Add capacity-dmips-mhz attributes
36ced612e4d3 mfd: cros_ec: add RTC as mfd subdevice
4e95dc697ec6 spi: rockchip: Convert to late and early system PM callbacks
d27d6da92086 drm/rockchip: analogix_dp: Ensure that the bridge is
powered before poking it
bcce86412ec1 arm64: DT: rk3399: Add missing EDP clock
c04436bd57b8 bootloader cmdline
bb8a4d168d58 build hacks
26e04c84de6c kevin: build stuff
6915015e30db kevin: defconfig
4a3928c6f8a5 (tag: v4.16-rc3) Linux 4.16-rc3


Actually, I also see some errors reading thermal channels, but I
wonder if perhaps USB is causing some sort of interrupt storm and that
happens to randomly take out whatever device was trying to talk at the
same time?

[   83.718999] read channel() error: -110
[   83.723275] thermal thermal_zone3: failed to read out thermal zone (-110)
[   83.822810] read channel() error: -110
[   83.827048] thermal thermal_zone2: failed to read out thermal zone (-110)
[   84.862810] read channel() error: -110
[   84.867051] thermal thermal_zone3: failed to read out thermal zone (-110)
[   84.990800] read channel() error: -110
[   84.995034] thermal thermal_zone2: failed to read out thermal zone (-110)
[   86.110817] read channel() error: -110
[   86.115259] thermal thermal_zone3: failed to read out thermal zone (-110)
[   86.214990] read channel() error: -110
[   86.219440] thermal thermal_zone2: failed to read out thermal zone (-110)
[   87.295049] read channel() error: -110
[   87.299316] thermal thermal_zone3: failed to read out thermal zone (-110)
[   87.398805] read channel() error: -110
[   87.403040] thermal thermal_zone2: failed to read out thermal zone (-110)
[   88.510808] read channel() error: -110
[   88.515053] thermal thermal_zone2: failed to read out thermal zone (-110)
[   88.646810] read channel() error: -110
[   88.651250] thermal thermal_zone3: failed to read out thermal zone (-110)
[   89.874606] xhci-hcd xhci-hcd.2.auto: Abort failed to stop command ring: -110
[   89.896134] xhci-hcd xhci-hcd.2.auto: xHCI host controller not
responding, assume dead
[   89.905130] xhci-hcd xhci-hcd.2.auto: HC died; cleaning up
[   89.911491] xhci-hcd xhci-hcd.2.auto: Timeout while waiting for
configure endpoint command


> I use my kevin as a "real" laptop, which means it gets suspended/resumed
> at least 20 times a day, no reboots involved (unless I'm actually testing
> arm64 code on it).

Enric: I know you've been working with Kevin stuff a lot.  Any chance
you reproduce Marc's failures and also see that it's fixed with his
hack patch?

Marc: have you posted actual logs for the failing case (after picking
my dts fix) somewhere?


Unfortunately, I don't think I'll be able to devote a ton more time to
debugging this right now.  :(

-Doug