x86, sched: Fix the AMD CPPC maximum performance value on certain AMD Ryzen generations
authorHuang Rui <ray.huang@amd.com>
Sun, 25 Apr 2021 07:34:51 +0000 (15:34 +0800)
committerIngo Molnar <mingo@kernel.org>
Thu, 13 May 2021 10:10:24 +0000 (12:10 +0200)
commit3743d55b289c203d8f77b7cd47c24926b9d186ae
tree8a9f28d591c88bc7a014d2464096409237a0867e
parent02dbb7246c5bbbbe1607ebdc546ba5c454a664b1
x86, sched: Fix the AMD CPPC maximum performance value on certain AMD Ryzen generations

Some AMD Ryzen generations has different calculation method on maximum
performance. 255 is not for all ASICs, some specific generations should use 166
as the maximum performance. Otherwise, it will report incorrect frequency value
like below:

  ~ → lscpu | grep MHz
  CPU MHz:                         3400.000
  CPU max MHz:                     7228.3198
  CPU min MHz:                     2200.0000

[ mingo: Tidied up whitespace use. ]
[ Alexander Monakov <amonakov@ispras.ru>: fix 225 -> 255 typo. ]

Fixes: 41ea667227ba ("x86, sched: Calculate frequency invariance for AMD systems")
Fixes: 3c55e94c0ade ("cpufreq: ACPI: Extend frequency tables to cover boost frequencies")
Reported-by: Jason Bagavatsingham <jason.bagavatsingham@gmail.com>
Fixed-by: Alexander Monakov <amonakov@ispras.ru>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Jason Bagavatsingham <jason.bagavatsingham@gmail.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210425073451.2557394-1-ray.huang@amd.com
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=211791
Signed-off-by: Ingo Molnar <mingo@kernel.org>
arch/x86/include/asm/processor.h
arch/x86/kernel/cpu/amd.c
arch/x86/kernel/smpboot.c
drivers/cpufreq/acpi-cpufreq.c