Kernel trace with custom stm32mp151c board and device tree (Workqueue: events deferred_probe_work_func)

[MScho.6]

Hi!

I have a custom board with custom device tree. As far as I can say, it works (boot over emmc) but the kernel gives a trace at the start.

[    0.255543] debugfs: Directory 'cpu0' with parent 'opp' already present!
[    0.261757] Unable to get STM32 DDR PMU clock
[    0.294819] stm32-mdma 58000000.dma: STM32 MDMA driver registered
[    0.296155] stm32-dma 48000000.dma: no dma pool: can't use MDMA: 0
[    0.297740] stm32-dma 48000000.dma: STM32 DMA driver registered
[    0.298366] reg11: supplied by fixed_3v3
[    0.298741] reg18: supplied by fixed_3v3
[    0.299068] usb33: supplied by fixed_3v3
[    0.304778] dwc2 49000000.usb-otg: 49000000.usb-otg supply vusb_d not found, using dummy regulator
[    0.304931] dwc2 49000000.usb-otg: 49000000.usb-otg supply vusb_a not found, using dummy regulator
[    0.307539] debugfs: Directory 'cpu0' with parent 'opp' already present!
[    0.307696] ------------[ cut here ]------------
[    0.307729] WARNING: CPU: 0 PID: 16 at drivers/opp/of.c:686 _of_add_opp_table_v2+0x50c/0x5c0
[    0.307738] Modules linked in:
[    0.307757] CPU: 0 PID: 16 Comm: kworker/0:1 Not tainted 5.4.69-yocto-standard #1
[    0.307766] Hardware name: STM32 (Device Tree Support)
[    0.307787] Workqueue: events deferred_probe_work_func
[    0.307825] [<c01104b4>] (unwind_backtrace) from [<c010c6d0>] (show_stack+0x10/0x14)
[    0.307849] [<c010c6d0>] (show_stack) from [<c0aa6d4c>] (dump_stack+0xbc/0xd0)
[    0.307871] [<c0aa6d4c>] (dump_stack) from [<c0122c7c>] (__warn+0xbc/0xd8)
[    0.307890] [<c0122c7c>] (__warn) from [<c0122cfc>] (warn_slowpath_fmt+0x64/0xc4)
[    0.307911] [<c0122cfc>] (warn_slowpath_fmt) from [<c0824c38>] (_of_add_opp_table_v2+0x50c/0x5c0)
[    0.307932] [<c0824c38>] (_of_add_opp_table_v2) from [<c0824d20>] (dev_pm_opp_of_add_table+0x34/0x164)
[    0.307953] [<c0824d20>] (dev_pm_opp_of_add_table) from [<c0824e88>] (dev_pm_opp_of_cpumask_add_table+0x38/0xfc)
[    0.307973] [<c0824e88>] (dev_pm_opp_of_cpumask_add_table) from [<c082c070>] (cpufreq_init+0x104/0x304)
[    0.307994] [<c082c070>] (cpufreq_init) from [<c0828f4c>] (cpufreq_online+0x420/0x9b4)
[    0.308016] [<c0828f4c>] (cpufreq_online) from [<c082957c>] (cpufreq_add_dev+0x8c/0xc0)
[    0.308036] [<c082957c>] (cpufreq_add_dev) from [<c05e86d4>] (subsys_interface_register+0xa4/0xf8)
[    0.308057] [<c05e86d4>] (subsys_interface_register) from [<c082789c>] (cpufreq_register_driver+0x150/0x2ac)
[    0.308078] [<c082789c>] (cpufreq_register_driver) from [<c082c314>] (dt_cpufreq_probe+0xa4/0x1b8)
[    0.308098] [<c082c314>] (dt_cpufreq_probe) from [<c05ec514>] (platform_drv_probe+0x48/0x98)
[    0.308117] [<c05ec514>] (platform_drv_probe) from [<c05ea360>] (really_probe+0x24c/0x488)
[    0.308136] [<c05ea360>] (really_probe) from [<c05ea764>] (driver_probe_device+0x78/0x154)
[    0.308154] [<c05ea764>] (driver_probe_device) from [<c05e83b0>] (bus_for_each_drv+0x84/0xd0)
[    0.308171] [<c05e83b0>] (bus_for_each_drv) from [<c05ea074>] (__device_attach+0xf0/0x188)
[    0.308189] [<c05ea074>] (__device_attach) from [<c05e917c>] (bus_probe_device+0x84/0x8c)
[    0.308207] [<c05e917c>] (bus_probe_device) from [<c05e96cc>] (deferred_probe_work_func+0x84/0xc4)
[    0.308228] [<c05e96cc>] (deferred_probe_work_func) from [<c013ce34>] (process_one_work+0x1c8/0x420)
[    0.308248] [<c013ce34>] (process_one_work) from [<c013d2d4>] (worker_thread+0x248/0x528)
[    0.308267] [<c013d2d4>] (worker_thread) from [<c0142670>] (kthread+0x144/0x180)
[    0.308285] [<c0142670>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
[    0.308295] Exception stack(0xc717bfb0 to 0xc717bff8)
[    0.308310] bfa0:                                     00000000 00000000 00000000 00000000
[    0.308326] bfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[    0.308341] bfe0: 00000000 00000000 00000000 00000000 00000013 00000000
[    0.308352] ---[ end trace 872afcafb31983a3 ]---
[    0.308802] debugfs: Directory 'cpu0' with parent 'opp' already present!
[    0.308884] sysfs: cannot create duplicate filename '/devices/platform/cpufreq-dt'
[    0.308903] CPU: 0 PID: 16 Comm: kworker/0:1 Tainted: G        W         5.4.69-yocto-standard #1
[    0.308911] Hardware name: STM32 (Device Tree Support)
[    0.308929] Workqueue: events deferred_probe_work_func
[    0.308958] [<c01104b4>] (unwind_backtrace) from [<c010c6d0>] (show_stack+0x10/0x14)
[    0.308979] [<c010c6d0>] (show_stack) from [<c0aa6d4c>] (dump_stack+0xbc/0xd0)
[    0.309001] [<c0aa6d4c>] (dump_stack) from [<c02f044c>] (sysfs_warn_dup+0x54/0x60)
[    0.309021] [<c02f044c>] (sysfs_warn_dup) from [<c02f0588>] (sysfs_create_dir_ns+0xec/0xfc)
[    0.309041] [<c02f0588>] (sysfs_create_dir_ns) from [<c0aac3ac>] (kobject_add_internal+0xb4/0x354)
[    0.309060] [<c0aac3ac>] (kobject_add_internal) from [<c0aac6a8>] (kobject_add+0x5c/0xc8)
[    0.309082] [<c0aac6a8>] (kobject_add) from [<c05e59fc>] (device_add+0x110/0x640)
[    0.309104] [<c05e59fc>] (device_add) from [<c05ec2b0>] (platform_device_add+0x108/0x248)
[    0.309125] [<c05ec2b0>] (platform_device_add) from [<c05ece4c>] (platform_device_register_full+0xd0/0x110)
[    0.309146] [<c05ece4c>] (platform_device_register_full) from [<c082c53c>] (stm32_cpufreq_probe+0xec/0x194)
[    0.309166] [<c082c53c>] (stm32_cpufreq_probe) from [<c05ec514>] (platform_drv_probe+0x48/0x98)
[    0.309185] [<c05ec514>] (platform_drv_probe) from [<c05ea360>] (really_probe+0x24c/0x488)
[    0.309204] [<c05ea360>] (really_probe) from [<c05ea764>] (driver_probe_device+0x78/0x154)
[    0.309222] [<c05ea764>] (driver_probe_device) from [<c05e83b0>] (bus_for_each_drv+0x84/0xd0)
[    0.309239] [<c05e83b0>] (bus_for_each_drv) from [<c05ea074>] (__device_attach+0xf0/0x188)
[    0.309257] [<c05ea074>] (__device_attach) from [<c05e917c>] (bus_probe_device+0x84/0x8c)
[    0.309275] [<c05e917c>] (bus_probe_device) from [<c05e96cc>] (deferred_probe_work_func+0x84/0xc4)
[    0.309294] [<c05e96cc>] (deferred_probe_work_func) from [<c013ce34>] (process_one_work+0x1c8/0x420)
[    0.309314] [<c013ce34>] (process_one_work) from [<c013d2d4>] (worker_thread+0x248/0x528)
[    0.309333] [<c013d2d4>] (worker_thread) from [<c0142670>] (kthread+0x144/0x180)
[    0.309350] [<c0142670>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
[    0.309360] Exception stack(0xc717bfb0 to 0xc717bff8)
[    0.309373] bfa0:                                     00000000 00000000 00000000 00000000
[    0.309390] bfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[    0.309405] bfe0: 00000000 00000000 00000000 00000000 00000013 00000000
[    0.309419] kobject_add_internal failed for cpufreq-dt with -EEXIST, don't try to register things with the same name in the same directory.
[    0.310927] stm32-hash 54002000.hash: will run requests pump with realtime priority
[    0.312665] stm32-hash 54002000.hash: Init HASH done HW ver 23 DMA mode 1
[    0.313866] stm32-ddr-pmu: probed (ID=0x00140061 VER=0x00000010), DDR@533MHz

Thanks and Regards,

Matthias

[Olivier GALLIEN]

Hi @MScho.6​ ,

I guess you get similar issue than in this post :

https://community.st.com/s/question/0D53W000009340DSAQ/how-to-configuration-for-stm32mp151

The patch to be applied is explain in the comment marked "Best Answer" .

Proper fix will be integrated in a coming release.

Olivier

[Olivier GALLIEN · Accepted solution]

To be more specific, fix is this one :

It was also nessesary to blacklist the device_id in drivers/cpufreq/cpufreq-dt-platdev.c

static const struct of_device_id blacklist[] __initconst = {

...

{ .compatible = "st,stm32mp157", },

+++ { .compatible = "st,stm32mp151", },

Olivier

[MScho.6]

No, I do not believe it has to do with that. The second trace is from: drivers/cpufreq/stm32-cpufreq.c:67 if that helps. We have a discrete power supply. Maybe some misconfiguration on my side there?! What are the dt nodes one should look at?

[Olivier GALLIEN]

Hi @MScho.6​ ,

Did you make a trial of the patch ?

Please provide new traces once applied

Olivier

[MScho.6]

I tried and the patch did it. Thank you and have a nice weekend.

[DMårt]

@Olivier GALLIEN 

Please add that to the next version of OpenSTLinux sources for STM32MP151. It removes at least one error.

[Olivier GALLIEN]

Hi @DMårt 

The bug mentioned in this thread supposed to be fixed and integrated for a while. (2021)

If you faced similar error using the latest version 5.0 or 5.1 please create a new topic/question. 

Thanks 

Olivier  

[DMårt]

@Olivier GALLIEN 

Yes....supposed to be fixed...supposed yes.

https://github.com/STMicroelectronics/linux/blob/4c4175804a542f40c50d091cc694bb0b186728a0/drivers/cpufreq/cpufreq-dt-platdev.c#L157

	{ .compatible = "st,stih407", },
	{ .compatible = "st,stih410", },
	{ .compatible = "st,stih418", },
	{ .compatible = "st,stm32mp157", },

The stm32mp153 and stm32mp151 are still missing.  Anyway! I'm working on a STM32MP151 low cost board with eMMC. If you are interested, you can have a look at it.