4.4-stable review patch. If anyone has any objections, please let me know.
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From: Shunyong Yang shunyong.yang@hxt-semitech.com
[ 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 --- drivers/cpufreq/cppc_cpufreq.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-)
--- a/drivers/cpufreq/cppc_cpufreq.c +++ b/drivers/cpufreq/cppc_cpufreq.c @@ -100,9 +100,19 @@ static int cppc_cpufreq_cpu_init(struct policy->cpuinfo.max_freq = policy->max; 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;