cpufreq: CPPC: Initialize shared perf capabilities of CPUs

[ Upstream commit 8913315e9459b146e5888ab5138e10daa061b885 ]

When multiple CPUs are related in one cpufreq policy, the first online
CPU will be chosen by default to handle cpufreq operations. Let's take
cpu0 and cpu1 as an example.

When cpu0 is offline, policy->cpu will be shifted to cpu1. cpu1's perf
capabilities should be initialized. Otherwise, perf capabilities are 0s
and speed change can not take effect.

This patch copies perf capabilities of the first online CPU to other
shared CPUs when policy shared type is CPUFREQ_SHARED_TYPE_ANY.

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Shunyong Yang <shunyong.yang@hxt-semitech.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
index dcb1cb9a4572a6220956bc59b3b57be9b752d588..a81f7d5af060a4465ac4c3fde50600b1f08ae488 100644 (file)
--- a/drivers/cpufreq/cppc_cpufreq.c
+++ b/drivers/cpufreq/cppc_cpufreq.c
@@ -167,9 +167,19 @@ static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy)
                NSEC_PER_USEC;
        policy->shared_type = cpu->shared_type;
 
-       if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY)
+       if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
+               int i;
+
                cpumask_copy(policy->cpus, cpu->shared_cpu_map);
-       else if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL) {
+
+               for_each_cpu(i, policy->cpus) {
+                       if (unlikely(i == policy->cpu))
+                               continue;
+
+                       memcpy(&all_cpu_data[i]->perf_caps, &cpu->perf_caps,
+                              sizeof(cpu->perf_caps));
+               }
+       } else if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL) {
                /* Support only SW_ANY for now. */
                pr_debug("Unsupported CPU co-ord type\n");
                return -EFAULT;