Re: Juno-r2 WARNING kernel time clockevents.c cev_delta2ns clockevents_config.part

[Dan Carpenter <dan.carpenter@linaro.org>]

Hi Sudeep,

Could we revert commit 1fa3ed04ac55 ("arm64: dts: arm: Drop the
clock-frequency property from timer nodes")?  We're still getting this
warning on our Juno systems (with admittedly ancient firmware).

regards,
dan carpenter

On Tue, Jun 10, 2025 at 12:48:18PM +0530, Naresh Kamboju wrote:
> Regression while booting Juno-r2 with the Linux next-20250606
> the following kernel warnings found.
> 
> This boot warning was reproduced with juno-r2.dtb and juno-r2-scmi.dtb.
> 
> Regressions found on Juno-r2
> - boot warning
> 
> Regression Analysis:
> - New regression? Yes
> - Reproducibility? Yes
> 
> First seen on the next-20250606
> Good: next-20250512
> Bad:  next-20250606
> 
> The suspected patch that found between tags is,
> 
> # git show next-20250512..next-20250513 --
> arch/arm64/boot/dts/arm/juno-base.dtsi
> commit 1fa3ed04ac55134063e3cd465b41aeb26715e52a
> Author: Sudeep Holla <sudeep.holla@arm.com>
> Date:   Mon May 12 11:11:32 2025 +0100
> 
>     arm64: dts: arm: Drop the clock-frequency property from timer nodes
> 
>     Drop the clock-frequency property from the timer nodes, since it must be
>     configured by the boot/secure firmware.
> 
>     Cc: Liviu Dudau <liviu.dudau@arm.com>
>     Cc: Lorenzo Pieralisi <lpieralisi@kernel.org>
>     Cc: Mark Rutland <mark.rutland@arm.com>
>     Message-Id: <20250512101132.1743920-1-sudeep.holla@arm.com>
>     Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
> 
> diff --git a/arch/arm64/boot/dts/arm/juno-base.dtsi
> b/arch/arm64/boot/dts/arm/juno-base.dtsi
> index 055764d0b9e5..9ccb80821bdb 100644
> --- a/arch/arm64/boot/dts/arm/juno-base.dtsi
> +++ b/arch/arm64/boot/dts/arm/juno-base.dtsi
> @@ -10,7 +10,6 @@ / {
>         memtimer: timer@2a810000 {
>                 compatible = "arm,armv7-timer-mem";
>                 reg = <0x0 0x2a810000 0x0 0x10000>;
> -               clock-frequency = <50000000>;
>                 #address-cells = <1>;
>                 #size-cells = <1>;
>                 ranges = <0 0x0 0x2a820000 0x20000>;
> 
> 
> Boot regression: Juno-r2 WARNING kernel time clockevents.c
> cev_delta2ns clockevents_config.part
> 
> Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
> 
> ## Boot warning
> [    0.000000] timer_sp804: timer clock not found: -517
> [    0.000000] timer_sp804: arm,sp804 clock not found: -2
> [    0.000000] Failed to initialize
> '/bus@8000000/motherboard-bus@8000000/iofpga-bus@300000000/timer@110000':
> -22
> [    0.000000] timer_sp804: timer clock not found: -517
> [    0.000000] timer_sp804: arm,sp804 clock not found: -2
> [    0.000000] Failed to initialize
> '/bus@8000000/motherboard-bus@8000000/iofpga-bus@300000000/timer@120000':
> -22
> [    0.000000] arch_timer: frequency not available
> [    0.000000] ------------[ cut here ]------------
> [    0.000000] WARNING: CPU: 0 PID: 0 at kernel/time/clockevents.c:38
> cev_delta2ns (kernel/time/clockevents.c:38 (discriminator 1))
> [    0.000000] Modules linked in:
> [    0.000000] CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted
> 6.15.0-next-20250605 #1 PREEMPT
> [    0.000000] Hardware name: ARM Juno development board (r2) (DT)
> [    0.000000] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
> [    0.000000] pc : cev_delta2ns (kernel/time/clockevents.c:38
> (discriminator 1))
> [    0.000000] lr : clockevents_config.part.0 (kernel/time/clockevents.c:499)
> [    0.000000] sp : ffff800082923cd0
> [    0.000000] x29: ffff800082923cd0 x28: 0000000000000400 x27: ffff800081650000
> [    0.000000] x26: ffff80008292fcc0 x25: ffff800082425888 x24: ffff8000829343c0
> [    0.000000] x23: ffff800083210000 x22: 000000000000000b x21: ffff8000823cf178
> [    0.000000] x20: ffff800082433880 x19: ffff00080021e240 x18: 0000000000000000
> [    0.000000] x17: ffff00080021a400 x16: ffff00080021a200 x15: 0000000000000100
> [    0.000000] x14: fffffdffe0008a00 x13: ffff800080000000 x12: 0000000000000000
> [    0.000000] x11: 0000000000000068 x10: 0000000000000100 x9 : ffff8000801b50f8
> [    0.000000] x8 : 000000001dcd6500 x7 : 000000003b9aca00 x6 : 0000000000000020
> [    0.000000] x5 : 0000000000000020 x4 : 0000000000000000 x3 : 0000000f00000000
> [    0.000000] x2 : 0000000000000000 x1 : ffff00080021e240 x0 : 000000000000000f
> [    0.000000] Call trace:
> [    0.000000] cev_delta2ns (kernel/time/clockevents.c:38 (discriminator 1)) (P)
> [    0.000000] clockevents_config_and_register (kernel/time/clockevents.c:519)
> [    0.000000] arch_timer_mem_frame_register
> (drivers/clocksource/arm_arch_timer.c:1319
> drivers/clocksource/arm_arch_timer.c:1580)
> [    0.000000] arch_timer_mem_of_init
> (drivers/clocksource/arm_arch_timer.c:1653)
> [    0.000000] timer_probe (drivers/clocksource/timer-probe.c:31)
> [    0.000000] time_init (arch/arm64/kernel/time.c:62)
> [    0.000000] start_kernel (init/main.c:1014)
> [    0.000000] __primary_switched (arch/arm64/kernel/head.S:247)
> [    0.000000] ---[ end trace 0000000000000000 ]---
> [    0.000000] arch_timer: cp15 and mmio timer(s) running at 50.00MHz
> (phys/phys).
> 
> ## Source
> * Kernel version: 6.15.0-next-20250513 to 6.15.0-next-20250606
> * Git tree: https://kernel.googlesource.com/pub/scm/linux/kernel/git/next/linux-next.git
> * Git sha: 4f27f06ec12190c7c62c722e99ab6243dea81a94
> * Toolchain: gcc-13
> 
> ## Boot details
> * Boot lava log: https://lkft.validation.linaro.org/scheduler/job/8309469#L622
> * Boot log: https://qa-reports.linaro.org/api/testruns/28679128/log_file/
> * Boot warning:
> https://regressions.linaro.org/lkft/linux-next-master/next-20250605/log-parser-boot/exception-warning-cpu-pid-at-kerneltimeclockevents-cev_delta2ns/
> * Build link:  https://storage.tuxsuite.com/public/linaro/lkft/builds/2y4wgEvmeoVH3Vr528M4YN2OBXY/
> * Kernel config:
> https://storage.tuxsuite.com/public/linaro/lkft/builds/2y4wgEvmeoVH3Vr528M4YN2OBXY/config
> 
> --
> Linaro LKFT
> https://lkft.linaro.org