allwinner/i2c interrupt storm detected

[Manuel Stühn]

On Tue, 30 Jun 2020 16:01:41 +0300
Daniel Braniss <danny at cs.huji.ac.il> wrote:

> Hi,
> 
> after a long time I decided to try and upgrade to stable 12.1 r362793 since I saw some changes where done 
> with respect to the DTS and twsi.c, 
> 
> if nothing is connected to the i2c, i2c -s just hangs,
> 
> if something is connected this is what i get on the console after typing ?i2c -s?
> 
> 
> Hardware may not support START/STOP scanning; trinterrupt storm detected on "gic0,s6:"; throttling interrupt source
> ying less-reliable read method.
> interrupt storm detected on "gic0,s6:"; throttling interrupt source
> interrupt storm detected on "gic0,s6:"; throttling interrupt source
> ?
> 
> and
> neo-04> vmstat -i
> interrupt                                             total       rate
> gic0,p13:-ic_timer0                                   16052        164
> gic0,s0: uart2                                          318          3
> gic0,s6: iichb0                                       13034        133
> gic0,s60: aw_mmc0                                      1293         13
> gic0,s82: awg0                                          334          3
> gic0,s120: pmu0                                       49725        509
> cpu0:rendezvous                                          18          0
> cpu1:rendezvous                                          50          1
> cpu2:rendezvous                                          51          1
> cpu3:rendezvous                                          40          0
> cpu0:preempt                                           2691         28
> cpu1:preempt                                           3165         32
> cpu2:preempt                                           2778         28
> cpu3:preempt                                           2986         31
> cpu0:hardclock                                           15          0
> Total                                                 92550        946
> 
> 
> the hardware is an NanoPi Neo
> ---<<BOOT>>---
> KDB: debugger backends: ddb
> KDB: current backend: ddb
> Copyright (c) 1992-2020 The FreeBSD Project.
> Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994
>        The Regents of the University of California. All rights reserved.
> FreeBSD is a registered trademark of The FreeBSD Foundation.
> FreeBSD 12.1-STABLE #0 r362793M: Tue Jun 30 11:39:11 IDT 2020
>    danny at nrnd:/home/obj/nrnd/arm/neo/vol/rnd/stable/12/arm.armv7/sys/AWGEN arm
> FreeBSD clang version 10.0.0 (git at github.com <mailto:git at github.com>:llvm/llvm-project.git llvmorg-10.0.0-0-gd32170dbd5b)
> VT: init without driver.
> No PSCI/SMCCC call function found
> CPU: ARM Cortex-A7 r0p5 (ECO: 0x00000000)
> ?
> 

I do not have a IRQ-Storm on my NanoPI NEO2, but a "i2s -s" does never return. Commit v356609 broke i2c-support on my hardware (reverting this single commit fixed it, bugreport filed: https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=247576).

Perhaps it is worth a try for you also to revert this commit and test again...


BR
Manuel