for_each_possible_cpu() is currently used to initialize cpufreq.
However, in cpu_dev_register_generic(), for_each_present_cpu()
is used to register CPU devices which means the CPU devices are
only registered for present CPUs and not all possible CPUs.
With nosmp or maxcpus=0, only the boot CPU is present, lead
to the cpufreq probe failure or defer probe due to no cpu device
available for not present CPUs.
Change for_each_possible_cpu() to for_each_present_cpu() in the
above cpufreq drivers to ensure it only registers cpufreq for
CPUs that are actually present.
Fixes: b0c69e1214 ("drivers: base: Use present CPUs in GENERIC_CPU_DEVICES")
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Jacky Bai <ping.bai@nxp.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
The cpufreq core now handles this for basic attributes, including boost
frequencies, the driver can skip setting them.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Introduce a virtualized cpufreq driver for guest kernels to improve
performance and power of workloads within VMs.
This driver does two main things:
1. Sends the frequency of vCPUs as a hint to the host. The host uses the
hint to schedule the vCPU threads and decide physical CPU frequency.
2. If a VM does not support a virtualized FIE(like AMUs), it queries the
host CPU frequency by reading a MMIO region of a virtual cpufreq device
to update the guest's frequency scaling factor periodically. This enables
accurate Per-Entity Load Tracking for tasks running in the guest.
Co-developed-by: Saravana Kannan <saravanak@google.com>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Signed-off-by: David Dai <davidai@google.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
