Linux 4.19.0 Build Error when CONFIG_ACPI not set.

[Thomas-Mich Richter <tmricht@linux.ibm.com>]

When I compile the 4.19.0 Linux kernel, I get this build error:

[root@f28 linux]# fgrep -r CONFIG_ACPI .config
# CONFIG_ACPI is not set
[root@f28 linux]#

[root@f28 linux]# make
  CALL    scripts/checksyscalls.sh
  DESCEND  objtool
  CHK     include/generated/compile.h
  CC      drivers/cpufreq/intel_pstate.o
drivers/cpufreq/intel_pstate.c: In function ‘show_base_frequency’:
        drivers/cpufreq/intel_pstate.c:726:10: error: implicit declaration of
        function ‘intel_pstate_get_cppc_guranteed’;
        did you mean ‘intel_pstate_get_epp’?
        [-Werror=implicit-function-declaration]
        ratio = intel_pstate_get_cppc_guranteed(policy->cpu);
                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
                intel_pstate_get_epp
cc1: some warnings being treated as errors
make[2]: *** [scripts/Makefile.build:306: drivers/cpufreq/intel_pstate.o]
                Error 1
make[1]: *** [scripts/Makefile.build:546: drivers/cpufreq] Error 2
make: *** [Makefile:1052: drivers] Error 2
[root@f28 linux]# 

I am building on a virtual machine.

This was introduced with
commit 86d333a8cc7f ("cpufreq: intel_pstate: Add base_frequency attribute")

The function intel_pstate_get_cppc_guranteed() is called but the function
definition is within #ifdef CONFIG_ACPI/#endif conditional compile.

Any ideas how to fix this?
Thanks

-- 
Thomas Richter, Dept 3303, IBM s390 Linux Development, Boeblingen, Germany
--
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