diff options
| author | Hoan Tran <hotran@apm.com> | 2016-10-13 20:33:35 +0300 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2016-10-14 00:10:41 +0300 |
| commit | c197d758036d8c77923ae3f88571cf198283107e (patch) | |
| tree | 9dea7912efc8aa2036eec6c157403643a3e07f5a /drivers/cpufreq | |
| parent | abb6627910a1e783c8e034b35b7c80e5e7f98f41 (diff) | |
| download | linux-c197d758036d8c77923ae3f88571cf198283107e.tar.xz | |
cpufreq: CPPC: Correct desired_perf calculation
The desired_perf is an abstract performance number. Its value should
be in the range of [lowest perf, highest perf] of CPPC.
The correct calculation is
desired_perf = freq * cppc_highest_perf / cppc_dmi_max_khz
And cppc_cpufreq_set_target() returns if desired_perf is exactly
the same with the old perf.
Signed-off-by: Hoan Tran <hotran@apm.com>
Reviewed-by: Prashanth Prakash <pprakash@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/cpufreq')
| -rw-r--r-- | drivers/cpufreq/cppc_cpufreq.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c index 99db4227ae38..f7e98fc077c1 100644 --- a/drivers/cpufreq/cppc_cpufreq.c +++ b/drivers/cpufreq/cppc_cpufreq.c @@ -80,11 +80,17 @@ static int cppc_cpufreq_set_target(struct cpufreq_policy *policy, { struct cpudata *cpu; struct cpufreq_freqs freqs; + u32 desired_perf; int ret = 0; cpu = all_cpu_data[policy->cpu]; - cpu->perf_ctrls.desired_perf = (u64)target_freq * policy->max / cppc_dmi_max_khz; + desired_perf = (u64)target_freq * cpu->perf_caps.highest_perf / cppc_dmi_max_khz; + /* Return if it is exactly the same perf */ + if (desired_perf == cpu->perf_ctrls.desired_perf) + return ret; + + cpu->perf_ctrls.desired_perf = desired_perf; freqs.old = policy->cur; freqs.new = target_freq; |