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path: root/drivers/cpufreq/virtual-cpufreq.c (follow)
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2025-03-17cpufreq: Init cpufreq only for present CPUsJacky Bai1-1/+1
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: b0c69e1214bc ("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>
2025-02-07cpufreq: virtual: Stop setting cpufreq_driver->attr fieldViresh Kumar1-1/+0
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>
2024-10-29cpufreq: add virtual-cpufreq driverDavid Dai1-0/+333
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>