Hi ,

  FIrst of all , I hope I have posted my query in the right place . I am expecting software support/suggestions for the below issue.

   I am working on LTE which use USB interface and the Host Controller is USB 2.0 . The BSP is from NXP which supports Cadence USB 3.0 Host controller and with USB 3.0 supported cadence driver.NXP had used the   USB 3.0 host controller for USB type C based device.

  Cadence USB 3.0 based device driver seems to be backward compatible for USB 2.0 host controller .Since basic LTE functionalities seems to be working fine I continued to use the same driver in Linux 4.14.62 

  But I am facing a kernel warning of unhandled interrupt and the crash log points to cdns_irq function as shown below  The crash/kerenel warning is very random and not occuring all the time.

 

.691533] irq 36: nobody cared (try booting with the "irqpoll" option)

[ 1.698242] CPU: 0 PID: 87 Comm: kworker/0:1 Not tainted 4.9.88 #24

[ 1.704509] Hardware name: Freescale i.MX8QXP MEK (DT)

[ 1.709659] Workqueue: pm pm_runtime_work

[ 1.713675] Call trace:

[ 1.716123] [<ffff0000080897d0>] dump_backtrace+0x0/0x1b0

[ 1.721523] [<ffff000008089994>] show_stack+0x14/0x20

[ 1.726582] [<ffff0000083daff0>] dump_stack+0x94/0xb4

[ 1.731638] [<ffff00000810f064>] __report_bad_irq+0x34/0xf0

[ 1.737212] [<ffff00000810f4ec>] note_interrupt+0x2e4/0x330

[ 1.742790] [<ffff00000810c594>] handle_irq_event_percpu+0x44/0x58

[ 1.748974] [<ffff00000810c5f0>] handle_irq_event+0x48/0x78

[ 1.754553] [<ffff0000081100a8>] handle_fasteoi_irq+0xc0/0x1b0

[ 1.760390] [<ffff00000810b584>] generic_handle_irq+0x24/0x38

[ 1.766141] [<ffff00000810bbe4>] __handle_domain_irq+0x5c/0xb8

[ 1.771979] [<ffff000008081798>] gic_handle_irq+0x70/0x15c

1.807416] 7a40: 00000000000002ba ffff80002645bf00 00000000fa83b2da 0000000001fe116e

[ 1.815252] 7a60: ffff000088bf7c47 ffffffffffffffff 00000000000003f8 ffff0000085c47b8

[ 1.823088] 7a80: 0000000000000010 ffff800026484600 0000000000000001 ffff8000266e9718

[ 1.830925] 7aa0: ffff00000b8b0008 ffff800026784280 ffff00000b8b000c ffff00000b8d8018

[ 1.838760] 7ac0: 0000000000000001 ffff000008b76000 0000000000000000 ffff800026497b20

[ 1.846596] 7ae0: ffff00000810bd24 ffff800026497b20 ffff000008851d18 0000000000000145

[ 1.854433] 7b00: ffff000008b8d6c0 ffff0000081102d8 ffffffffffffffff ffff00000810dda8

[ 1.862268] [<ffff000008082eec>] el1_irq+0xac/0x120

[ 1.867155] [<ffff000008851d18>] _raw_spin_unlock_irqrestore+0x18/0x48

[ 1.873684] [<ffff00000810bd24>] __irq_put_desc_unlock+0x1c/0x48

[ 1.879695] [<ffff00000810de10>] enable_irq+0x48/0x70

[ 1.884756] [<ffff0000085ba8f8>] cdns3_enter_suspend+0x1f0/0x440

[ 1.890764] [<ffff0000085baca0>] cdns3_runtime_suspend+0x48/0x88

[ 1.896776] [<ffff0000084cf398>] pm_generic_runtime_suspend+0x28/0x40

[ 1.903223] [<ffff0000084dc3e8>] genpd_runtime_suspend+0x88/0x1d8

[ 1.909320] [<ffff0000084d0e08>] __rpm_callback+0x70/0x98

[ 1.914724] [<ffff0000084d0e50>] rpm_callback+0x20/0x88

[ 1.919954] [<ffff0000084d1b2c>] rpm_suspend+0xf4/0x4c8

[ 1.925184] [<ffff0000084d20fc>] rpm_idle+0x124/0x168

[ 1.930240] [<ffff0000084d26c0>] pm_runtime_work+0xa0/0xb8

[ 1.935732] [<ffff0000080dc1dc>] process_one_work+0x1dc/0x380

[ 1.941481] [<ffff0000080dc3c8>] worker_thread+0x48/0x4d0

[ 1.946885] [<ffff0000080e2408>] kthread+0xf8/0x100
[ 1.957080] handlers:

[ 1.959350] [<ffff0000085ba668>] cdns3_irq

[ 1.963449] Disabling IRQ #36

 Kindly provide a solution to solve this issue.

Thanks & Regards,

Anjali

An independently powered USB connector is provided. The independently powered USB connector replaces the computer USB power supply for the direct transmission of digital signals from and between computers and audio components, eliminating micro-circuitry and computer generated noise from the digital signal chain so as to prevent sonic coloration from these sources. The independent power supply is coupled to the male connection of the USB connector, wherein the coupling is wrapped with shrink wrap designed for stability.