Add sysfs interfaces for CPPC autonomous selection in the cppc_cpufreq
driver.

Signed-off-by: Lifeng Zheng <zhenglifeng1@huawei.com>
Reviewed-by: Sumit Gupta <sumitg@nvidia.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://patch.msgid.link/20250507031941.2812701-1-zhenglifeng1@huawei.com
[ rjw: Subject edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Returning a negative error code in a function with an unsigned
return type is a pretty bad idea. It is probably worse when the
justification for the change is "our static analisys tool found it".

Fixes: cf7de25878a1 ("cppc_cpufreq: Fix possible null pointer dereference")
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Lifeng Zheng <zhenglifeng1@huawei.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

With a later commit, the cpufreq core will call the ->set_boost()
callback only if the policy supports boost frequency. The
boost_supported flag is set by the cpufreq core if policy->freq_table is
set and one or more boost frequencies are present.

For other drivers, the flag must be set explicitly.

With this, the local variable boost_supported isn't required anymore.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

In policy initialization, policy->max and policy->cpuinfo.max_freq are
always set to the value calculated from caps->nominal_perf.

This will cause the frequency stay on base frequency even if the policy
is already boosted when a CPU is going online.

Fix this by using policy->boost_enabled to determine which value should
be set.

Signed-off-by: Lifeng Zheng <zhenglifeng1@huawei.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://patch.msgid.link/20250117101457.1530653-4-zhenglifeng1@huawei.com
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

kthread_create() creates a kthread without running it yet. kthread_run()
creates a kthread and runs it.

On the other hand, kthread_create_worker() creates a kthread worker and
runs it.

This difference in behaviours is confusing. Also there is no way to
create a kthread worker and affine it using kthread_bind_mask() or
kthread_affine_preferred() before starting it.

Consolidate the behaviours and introduce kthread_run_worker[_on_cpu]()
that behaves just like kthread_run(). kthread_create_worker[_on_cpu]()
will now only create a kthread worker without starting it.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>

Merge ARM cpufreq updates for 6.13 from Viresh Kumar:

"- Add virtual cpufreq driver for guest kernels (David Dai).

 - Minor cleanup to various cpufreq drivers (Andy Shevchenko, Dhruva
   Gole, Jie Zhan, Jinjie Ruan, Shuosheng Huang, Sibi Sankar, and Yuan
   Can).

 - Revert "cpufreq: brcmstb-avs-cpufreq: Fix initial command check"
   (Colin Ian King).

 - Improve DT bindings for qcom-hw driver (Dmitry Baryshkov, Konrad
   Dybcio, and Nikunj Kela)."

* tag 'cpufreq-arm-updates-6.13' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/vireshk/pm:
  arm64: dts: qcom: sc8180x: Add a SoC-specific compatible to cpufreq-hw
  dt-bindings: cpufreq: cpufreq-qcom-hw: Add SC8180X compatible
  cpufreq: sun50i: add a100 cpufreq support
  cpufreq: mediatek-hw: Fix wrong return value in mtk_cpufreq_get_cpu_power()
  cpufreq: CPPC: Fix wrong return value in cppc_get_cpu_power()
  cpufreq: CPPC: Fix wrong return value in cppc_get_cpu_cost()
  cpufreq: loongson3: Check for error code from devm_mutex_init() call
  cpufreq: scmi: Fix cleanup path when boost enablement fails
  cpufreq: CPPC: Fix possible null-ptr-deref for cppc_get_cpu_cost()
  cpufreq: CPPC: Fix possible null-ptr-deref for cpufreq_cpu_get_raw()
  Revert "cpufreq: brcmstb-avs-cpufreq: Fix initial command check"
  dt-bindings: cpufreq: cpufreq-qcom-hw: Add SAR2130P compatible
  cpufreq: add virtual-cpufreq driver
  dt-bindings: cpufreq: add virtual cpufreq device
  cpufreq: loongson2: Unregister platform_driver on failure
  cpufreq: ti-cpufreq: Remove revision offsets in AM62 family
  cpufreq: ti-cpufreq: Allow backward compatibility for efuse syscon
  cppc_cpufreq: Remove HiSilicon CPPC workaround
  cppc_cpufreq: Use desired perf if feedback ctrs are 0 or unchanged
  dt-bindings: cpufreq: qcom-hw: document support for SA8255p

cppc_get_cpu_power() return 0 if the policy is NULL. Then in
em_create_perf_table(), the later zero check for power is not valid
as power is uninitialized. As Quentin pointed out, kernel energy model
core check the return value of active_power() first, so if the callback
failed it should tell the core. So return -EINVAL to fix it.

Fixes: a78e72075642 ("cpufreq: CPPC: Fix possible null-ptr-deref for cpufreq_cpu_get_raw()")
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Suggested-by: Quentin Perret <qperret@google.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

cppc_get_cpu_cost() return 0 if the policy is NULL. Then in
em_compute_costs(), the later zero check for cost is not valid
as cost is uninitialized. As Quentin pointed out, kernel energy model
core check the return value of get_cost() first, so if the callback
failed it should tell the core. Return -EINVAL to fix it.

Fixes: 1a1374bb8c59 ("cpufreq: CPPC: Fix possible null-ptr-deref for cppc_get_cpu_cost()")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/all/c4765377-7830-44c2-84fa-706b6e304e10@stanley.mountain/
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Suggested-by: Quentin Perret <qperret@google.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

cpufreq_cpu_get_raw() may return NULL if the cpu is not in
policy->cpus cpu mask and it will cause null pointer dereference,
so check NULL for cppc_get_cpu_cost().

Fixes: 740fcdc2c20e ("cpufreq: CPPC: Register EM based on efficiency class information")
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

cpufreq_cpu_get_raw() may return NULL if the cpu is not in
policy->cpus cpu mask and it will cause null pointer dereference.

Fixes: 740fcdc2c20e ("cpufreq: CPPC: Register EM based on efficiency class information")
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>