Commit f5f94b9c authored by Pierre Gondois's avatar Pierre Gondois Committed by Viresh Kumar
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cpufreq: CPPC: Add u64 casts to avoid overflowing 



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: default avatarPierre Gondois <pierre.gondois@arm.com>
Signed-off-by: default avatarViresh Kumar <viresh.kumar@linaro.org>
parent 83749a2e

drivers/cpufreq/cppc_cpufreq.c

+6 −5
Original line number Diff line number Diff line
@@ -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,

	min_cap = div_u64((u64)max_cap * perf_caps->lowest_perf,

			  perf_caps->highest_perf);



	perf_step = CPPC_EM_CAP_STEP * perf_caps->highest_perf / max_cap;

	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;