Frequency returned by 'cpuinfo_cur_freq' using counters is not fixed
and keeps changing slightly. This change returns a consistent value
from freq_table. If the reconstructed frequency has acceptable delta
from the last written value, then return the frequency corresponding
to the last written ndiv value from freq_table. Otherwise, print a
warning and return the reconstructed freq.
Signed-off-by: Sumit Gupta <sumitg@nvidia.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Commit eaecca9e77 ("arm64: Fix __cpu_logical_map undefined issue")
fixes the issue with building tegra194 cpufreq driver as module. But
the fix might cause problem while supporting physical CPU hotplug[1].
This patch fixes the original problem by avoiding use of cpu_logical_map().
Instead calling read_cpuid_mpidr() to get MPIDR on target CPU.
[1] https://lore.kernel.org/linux-arm-kernel/20200724131059.GB6521@bogus/
Fixes: df320f8935 ("cpufreq: Add Tegra194 cpufreq driver")
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Sumit Gupta <sumitg@nvidia.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw: Subject & changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add support for CPU frequency scaling on Tegra194. The frequency
of each core can be adjusted by writing a clock divisor value to
a MSR on the core. The range of valid divisors is queried from
the BPMP.
Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Sumit Gupta <sumitg@nvidia.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Sumit Gupta