]> git.baikalelectronics.ru Git - kernel.git/commit
cpufreq: CPPC: Use transition_delay_us depending transition_latency
authorGeorge Cherian <george.cherian@cavium.com>
Fri, 23 Mar 2018 10:30:31 +0000 (03:30 -0700)
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>
Fri, 30 Mar 2018 10:15:58 +0000 (12:15 +0200)
commitc41be4814333326ee8cc9e1ec5cbc99fb08ea848
tree3b04b6dfe0445d3e13f2ba7da722011a6fec894a
parent3b5068164e4a9a5fd455d39a4e5f169eca2b8556
cpufreq: CPPC: Use transition_delay_us depending transition_latency

With commit ff637461cf3e (cpufreq: Cap the default transition delay
value to 10 ms)  the cpufreq was not honouring the delay passed via
ACPI (PCCT). Due to which on ARM based platforms using CPPC the
cpufreq governor tries to change the frequency of CPUs faster than
expected.

This leads to continuous error messages like the following.
" ACPI CPPC: PCC check channel failed. Status=0 "

Earlier (without above commit) the default transition delay was
taken form the value passed from PCCT. Use the same value provided
by PCCT to set the transition_delay_us.

Fixes: ff637461cf3e (cpufreq: Cap the default transition delay value to 10 ms)
Signed-off-by: George Cherian <george.cherian@cavium.com>
Cc: 4.14+ <stable@vger.kernel.org> # 4.14+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
drivers/cpufreq/cppc_cpufreq.c