tools/power/x86/intel-speed-select: fix build failure when using -Wl,--as-needed

Build of intel-speed-select will fail if you run:

$ LDFLAGS="-Wl,--as-needed" /usr/bin/make V=1
...
gcc -O2 -Wall -g -D_GNU_SOURCE -Iinclude -I/usr/include/libnl3 -Wl,--as-needed -lnl-genl-3 -lnl-3 intel-speed-select-in.o -o intel-speed-select
/usr/bin/ld: intel-speed-select-in.o: in function `handle_event':
(...)/linux/tools/power/x86/intel-speed-select/hfi-events.c:189: undefined reference to `nlmsg_hdr'
...

In this case the problem is that order when linking matters when using
the flag -Wl,--as-needed, symbols not used at that point are discarded.
So since intel-speed-select-in.o comes after, at that point the
libraries/symbols are already discarded and then missing/undefined
references are reported.

To fix this, make sure we specify LDFLAGS after the object file.

Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Herton R. Krzesinski <herton@redhat.com>
Link: https://lore.kernel.org/r/20220404210525.725611-1-herton@redhat.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

kbuild: replace $(if A,A,B) with $(or A,B)

$(or ...) is available since GNU Make 3.81, and useful to shorten the
code in some places.

Covert as follows:

$(if A,A,B) --> $(or A,B)

This patch also converts:

$(if A, A, B) --> $(or A, B)

Strictly speaking, the latter is not an equivalent conversion because
GNU Make keeps spaces after commas; if A is not empty, $(if A, A, B)
expands to " A", while $(or A, B) expands to "A".

Anyway, preceding spaces are not significant in the code hunks I touched.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>

tools/power/x86/intel-speed-select: HFI support

Read HFI (Hardware Feedback Interface) events to process config level
changes in oob mode. When HFI is supported there is no need for polling
to check config level change.

Subscribe to Linux thermal netlink messages and process message:
THERMAL_GENL_EVENT_CPU_CAPABILITY_CHANGE.
This message contains cpu number, performance and energy efficiency.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>

tools/power/x86: A tool to validate Intel Speed Select commands

The Intel(R) Speed select technologies contains four features.

Performance profile:An non architectural mechanism that allows multiple
optimized performance profiles per system via static and/or dynamic
adjustment of core count, workload, Tjmax, and TDP, etc. aka ISS
in the documentation.

Base Frequency: Enables users to increase guaranteed base frequency on
certain cores (high priority cores) in exchange for lower base frequency
on remaining cores (low priority cores). aka PBF in the documenation.

Turbo frequency: Enables the ability to set different turbo ratio limits
to cores based on priority. aka FACT in the documentation.

Core power: An Interface that allows user to define per core/tile
priority.

There is a multi level help for commands and options. This can be used
to check required arguments for each feature and commands for the
feature.

To start navigating the features start with

$sudo intel-speed-select --help

For help on a specific feature for example
$sudo intel-speed-select perf-profile --help

To get help for a command for a feature for example
$sudo intel-speed-select perf-profile get-lock-status --help

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Acked-by: Len Brown <len.brown@intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>