[PATCH] arm64: topology: Do not warn on missing AMU in cpuhp_topology_online()

[PATCH] arm64: topology: Do not warn on missing AMU in cpuhp_topology_online()

[Geert Uytterhoeven]

When CONFIG_CPUMASK_OFFSTACK is not enabled, and resuming from s2ram on
Renesas R-Car H3 (big.LITTLE 4x Cortex-A57 + 4x Cortex-A53), during
enabling of the first little core, a warning message is printed:

    AMU: CPU[4] doesn't support AMU counters

This confuses users, as during boot amu_fie_setup() does not print such
a message, unless debugging is enabled (freq_counters_valid() prints
"CPU%d: counters are not supported.\n" at debug level in that case).

Hence drop the warning, freq_counters_valid() has already printed a
debug message anyway.

Fixes: 6fd9be0b7b2e957d ("arm64: topology: Handle AMU FIE setup on CPU hotplug")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
 arch/arm64/kernel/topology.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c
index 539b3893518281ec..3fe1faab03620e78 100644
--- a/arch/arm64/kernel/topology.c
+++ b/arch/arm64/kernel/topology.c
@@ -332,7 +332,6 @@ static int cpuhp_topology_online(unsigned int cpu)
 	 * may use different source of the freq scale.
 	 */
 	if (!freq_counters_valid(cpu)) {
-		pr_warn("CPU[%u] doesn't support AMU counters\n", cpu);
 		topology_clear_scale_freq_source(SCALE_FREQ_SOURCE_ARCH,
 						 policy->related_cpus);
 		cpumask_andnot(amu_fie_cpus, amu_fie_cpus, policy->related_cpus);
-- 
2.43.0

Re: [PATCH] arm64: topology: Do not warn on missing AMU in cpuhp_topology_online()

[zhenglifeng (A)]

On 2026/1/15 16:51, Geert Uytterhoeven wrote:
> When CONFIG_CPUMASK_OFFSTACK is not enabled, and resuming from s2ram on
> Renesas R-Car H3 (big.LITTLE 4x Cortex-A57 + 4x Cortex-A53), during
> enabling of the first little core, a warning message is printed:
> 
>     AMU: CPU[4] doesn't support AMU counters
> 
> This confuses users, as during boot amu_fie_setup() does not print such
> a message, unless debugging is enabled (freq_counters_valid() prints
> "CPU%d: counters are not supported.\n" at debug level in that case).
> 
> Hence drop the warning, freq_counters_valid() has already printed a
> debug message anyway.
> 
> Fixes: 6fd9be0b7b2e957d ("arm64: topology: Handle AMU FIE setup on CPU hotplug")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
>  arch/arm64/kernel/topology.c | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c
> index 539b3893518281ec..3fe1faab03620e78 100644
> --- a/arch/arm64/kernel/topology.c
> +++ b/arch/arm64/kernel/topology.c
> @@ -332,7 +332,6 @@ static int cpuhp_topology_online(unsigned int cpu)
>  	 * may use different source of the freq scale.
>  	 */
>  	if (!freq_counters_valid(cpu)) {
> -		pr_warn("CPU[%u] doesn't support AMU counters\n", cpu);
>  		topology_clear_scale_freq_source(SCALE_FREQ_SOURCE_ARCH,
>  						 policy->related_cpus);
>  		cpumask_andnot(amu_fie_cpus, amu_fie_cpus, policy->related_cpus);

Thanks!

Reviewed-by: Lifeng Zheng <zhenglifeng1@huawei.com>

Re: [PATCH] arm64: topology: Do not warn on missing AMU in cpuhp_topology_online()

[Will Deacon]

On Thu, 15 Jan 2026 09:51:45 +0100, Geert Uytterhoeven wrote:
> When CONFIG_CPUMASK_OFFSTACK is not enabled, and resuming from s2ram on
> Renesas R-Car H3 (big.LITTLE 4x Cortex-A57 + 4x Cortex-A53), during
> enabling of the first little core, a warning message is printed:
> 
>     AMU: CPU[4] doesn't support AMU counters
> 
> This confuses users, as during boot amu_fie_setup() does not print such
> a message, unless debugging is enabled (freq_counters_valid() prints
> "CPU%d: counters are not supported.\n" at debug level in that case).
> 
> [...]

Applied to arm64 (for-next/cpufreq), thanks!

[1/1] arm64: topology: Do not warn on missing AMU in cpuhp_topology_online()
      https://git.kernel.org/arm64/c/747d5b6735ca

Cheers,
-- 
Will

https://fixes.arm64.dev
https://next.arm64.dev
https://will.arm64.dev