Commit 785ee278 authored by Prarit Bhargava's avatar Prarit Bhargava Committed by Rafael J. Wysocki

cpufreq: intel_pstate: Fix limits->max_perf rounding error

A rounding error was found in the calculation of limits->max_perf
in intel_pstate_set_policy(), which is used to calculate the max and min
pstate values in intel_pstate_get_min_max().  In that code,
limits->max_perf is truncated to 2 hex digits such that, for example,
0x169 was incorrectly calculated to 0x16 instead of 0x17.  This resulted in
the pstate being set one level too low.  This patch rounds the value of
limits->max_perf up instead of down so that the correct max pstate can
be reached.
Signed-off-by: default avatarPrarit Bhargava <prarit@redhat.com>
Acked-by: default avatarSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Acked-by: default avatarViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 8478f539
...@@ -1121,6 +1121,7 @@ static int intel_pstate_set_policy(struct cpufreq_policy *policy) ...@@ -1121,6 +1121,7 @@ static int intel_pstate_set_policy(struct cpufreq_policy *policy)
limits->max_sysfs_pct); limits->max_sysfs_pct);
limits->max_perf_pct = max(limits->min_policy_pct, limits->max_perf_pct = max(limits->min_policy_pct,
limits->max_perf_pct); limits->max_perf_pct);
limits->max_perf = round_up(limits->max_perf, 8);
/* Make sure min_perf_pct <= max_perf_pct */ /* Make sure min_perf_pct <= max_perf_pct */
limits->min_perf_pct = min(limits->max_perf_pct, limits->min_perf_pct); limits->min_perf_pct = min(limits->max_perf_pct, limits->min_perf_pct);
......
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