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cpufreq: CPPC: Add u64 casts to avoid overflowing

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The fields of the _CPC object are unsigned 32-bits values.
To avoid overflows while using _CPC's values, add 'u64' casts.

Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
This commit is contained in:
Pierre Gondois 2022-12-20 11:12:25 +01:00 committed by Viresh Kumar
parent 83749a2ee5
commit f5f94b9c8b
1 changed files with 6 additions and 5 deletions
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11
drivers/cpufreq/cppc_cpufreq.c
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@ -487,7 +487,8 @@ static unsigned int get_perf_level_count(struct cpufreq_policy *policy)
cpu_data = policy->driver_data;
perf_caps = &cpu_data->perf_caps;
max_cap = arch_scale_cpu_capacity(cpu);
min_cap = div_u64(max_cap * perf_caps->lowest_perf, perf_caps->highest_perf);
min_cap = div_u64((u64)max_cap * perf_caps->lowest_perf,
perf_caps->highest_perf);
if ((min_cap == 0) || (max_cap < min_cap))
return 0;
return 1 + max_cap / CPPC_EM_CAP_STEP - min_cap / CPPC_EM_CAP_STEP;
@ -519,10 +520,10 @@ static int cppc_get_cpu_power(struct device *cpu_dev,
cpu_data = policy->driver_data;
perf_caps = &cpu_data->perf_caps;
max_cap = arch_scale_cpu_capacity(cpu_dev->id);
min_cap = div_u64(max_cap * perf_caps->lowest_perf,
perf_caps->highest_perf);
perf_step = CPPC_EM_CAP_STEP * perf_caps->highest_perf / max_cap;
min_cap = div_u64((u64)max_cap * perf_caps->lowest_perf,
perf_caps->highest_perf);
perf_step = div_u64((u64)CPPC_EM_CAP_STEP * perf_caps->highest_perf,
max_cap);
min_step = min_cap / CPPC_EM_CAP_STEP;
max_step = max_cap / CPPC_EM_CAP_STEP;