Re: [PATCH v8 00/19] Consolidate and improve NVIDIA Tegra CPUIDLE driver(s)

[Dmitry Osipenko]

10.12.2019 05:35, MichaÅ MirosÅaw ÐÐÑÐÑ:
> On Tue, Dec 10, 2019 at 12:22:18AM +0300, Dmitry Osipenko wrote:
>> 09.12.2019 19:04, MichaÅ MirosÅaw ÐÐÑÐÑ:
>>> On Sun, Dec 08, 2019 at 01:56:14AM +0300, Dmitry Osipenko wrote:
>>>> 08.12.2019 00:52, MichaÅ MirosÅaw ÐÐÑÐÑ:
>>>>> On Tue, Dec 03, 2019 at 03:40:57AM +0300, Dmitry Osipenko wrote:
>>>>>> Hello,
>>>>>>
>>>>>> This series does the following:
>>>>>>
>>>>>>   1. Unifies Tegra20/30/114 drivers into a single driver and moves it out
>>>>>>      into common drivers/cpuidle/ directory.
>>>>>>
>>>>>>   2. Enables CPU cluster power-down idling state on Tegra30.
>>>>>>
>>>>>> In the end there is a quite nice clean up of the Tegra CPUIDLE drivers
>>>>>> and of the Tegra's arch code in general. Please review, thanks!
>>>>>
>>>>> I did a quick smoke test for this series on top of Linus' master:
>>>>>  - rebuilding with the patches applied, CONFIG_ARM_TEGRA_CPUIDLE=n - works
>>>>>  - building with CONFIG_ARM_TEGRA_CPUIDLE=y - doesn't boot
>>>>>
>>>>> The hang is somewhere early in the boot process, before simplefb can
>>>>> take the console and show any logs. If I get BOOTFB to work again I might
>>>>> be able to get some more info.
>>>>
>>>> Thank you very much for trying these patches!
>>>>
>>>> Could you please try to make ARM_TEGRA_CPUIDLE "tristate" in the Kconfig
>>>> and compile it as a loadable module? That way you'll get framebuffer
>>>> shown before the hang happens.
>>>>
>>>> Does LP2 suspend/resume work for you? There should be
>>>> "nvidia,suspend-mode = <2>" in the PMC's node of device-tree.
>>>
>>> Not at the moment. I also tried suspend-mode = <1> and <0>, but it
>>> made no difference.
>>
>> If LP2 doesn't work, then it explains why you're getting the hang.
>>
>> Are you using TF300T for the testing? I'm recalling that LP2 worked for
>> you sometime ago on TF300T, maybe some offending change was introduced
>> since then. Could you please try to do the git bisection or at least
>> find out what is the last good kernel version?
>>
>> I rebased this series on a recent linux-next and you could find the
>> rebased patches here [1].
>>
>> [1] https://github.com/grate-driver/linux/commits/master
>>
>> With [1] you should be able to remove "nvidia,suspend-mode" property
>> from the device-tree to get cpuidle working with the disabled CC6 state
>> (LP2). Could you please check that at least disabled CC6 works for you?
> 
> I tested suspend with your tree merged, but CONFIG_TEGRA_CPUIDLE=n. LP2
> seems to work [1]. The same tree with CONFIG_TEGRA_CPUIDLE=y doesn't
> boot. I'll try comparing DTs, but other than that I'm blocked on BOOTFB now.

That's an interesting result.

> [1] rtcwake -s 3 -d /dev/rtc0 -v -m mem
> 
> (...)
> [ 2710.157919] PM: suspend entry (deep)
> [ 2710.161205] Filesystems sync: 0.000 seconds
> [ 2710.176677] Freezing user space processes ... (elapsed 0.001 seconds) done.
> [ 2710.178342] OOM killer disabled.
> [ 2710.178527] Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done.
> [ 2710.347871] Disabling non-boot CPUs ...
> [ 2710.349160] IRQ 18: no longer affine to CPU1
> [ 2710.352499] IRQ 19: no longer affine to CPU2
> [ 2710.370059] IRQ 20: no longer affine to CPU3
> [ 2710.371284] Entering suspend state LP2
> [ 2710.371556] Enabling non-boot CPUs ...
> [ 2710.373157] CPU1 is up
> [ 2710.374598] CPU2 is up
> [ 2710.375996] CPU3 is up
> [ 2710.462876] OOM killer enabled.
> [ 2710.463018] Restarting tasks ...
> [ 2710.463880] tegra-devfreq 6000c800.actmon: Failed to get emc clock
> [ 2710.464509] done.
> [ 2710.552824] asus-ec 1-0015: model         : ASUS-TF201-PAD
> [ 2710.558345] asus-ec 1-0015: FW version    : PAD-EC20T-0216
> [ 2710.562942] asus-ec 1-0015: Config format : ECFG-0001
> [ 2710.567651] asus-ec 1-0015: HW version    : TF201-PAD-SKU1
> [ 2710.572488] asus-ec 1-0015: EC FW behaviour: susb on when system wakeup
> [ 2710.769796] atkbd serio1: no of_node; not parsing pinctrl DT
> [ 2710.835629] asus-ec 5-0019: model         : ASUS-TF201-DOCK
> [ 2710.838686] asus-ec 5-0019: FW version    : DOCK-EC20N-0207
> [ 2710.841865] asus-ec 5-0019: Config format : ECFG-0001
> [ 2710.844271] asus-ec 5-0019: HW version    : PCBA-SKU-2
> [ 2710.847950] asus-ec 5-0019: EC FW behaviour: susb on when receive ec_req
> [ 2711.040935] PM: suspend exit
> 

Could you please try this change on top of recent grate-linux (it should
allow display to light up before the hang):

diff --git a/drivers/cpuidle/cpuidle-tegra.c
b/drivers/cpuidle/cpuidle-tegra.c
index db9ccba5a74c..21317b4e16c1 100644
--- a/drivers/cpuidle/cpuidle-tegra.c
+++ b/drivers/cpuidle/cpuidle-tegra.c
@@ -22,6 +22,7 @@
 #include <linux/ktime.h>
 #include <linux/platform_device.h>
 #include <linux/types.h>
+#include <linux/workqueue.h>

 #include <linux/clk/tegra.h>
 #include <linux/firmware/trusted_foundations.h>
@@ -332,7 +333,7 @@ static void tegra_cpuidle_setup_tegra114_c7_state(void)
 	s->exit_latency = 500;
 }

-static int tegra_cpuidle_probe(struct platform_device *pdev)
+static void tegra_cpuidle_probe_work(struct work_struct *work)
 {
 	/* LP2 could be disabled in device-tree */
 	if (tegra_pmc_get_suspend_mode() < TEGRA_SUSPEND_LP2)
@@ -372,10 +373,18 @@ static int tegra_cpuidle_probe(struct
platform_device *pdev)
 		break;

 	default:
-		return -EINVAL;
+		return;
 	}

-	return cpuidle_register(&tegra_idle_driver, cpu_possible_mask);
+	cpuidle_register(&tegra_idle_driver, cpu_possible_mask);
+}
+
+static DECLARE_DELAYED_WORK(delayed_probe, tegra_cpuidle_probe_work);
+
+static int tegra_cpuidle_probe(struct platform_device *pdev)
+{
+	schedule_delayed_work(&delayed_probe, 5 * HZ);
+	return 0;
 }

 static struct platform_driver tegra_cpuidle_driver = {