arm64: Factor out cpucap definitions

For clarity it would be nice to factor cpucap manipulation out of
<asm/cpufeature.h>, and the obvious place would be <asm/cpucap.h>, but
this will clash somewhat with <generated/asm/cpucaps.h>.

Rename <generated/asm/cpucaps.h> to <generated/asm/cpucap-defs.h>,
matching what we do for <generated/asm/sysreg-defs.h>, and introduce a
new <asm/cpucaps.h> which includes the generated header.

Subsequent patches will fill out <asm/cpucaps.h>.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

arm64/sysreg: Enable automatic generation of system register definitions

Now that we have a script for generating system registers hook it up to the
build system similarly to cpucaps. Since we don't currently have any actual
register information in the input file this should produce no change in the
built kernel. For ease of review the register information will be converted
in separate patches.

Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20220503170233.507788-10-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

arm64: clean up tools Makefile

Remove unused gen-y.

Remove redundant $(shell ...) because 'mkdir' is done in cmd_gen_cpucaps.

Replace $(filter-out $(PHONY), $^) with the $(real-prereqs) shorthand.

The '&&' in cmd_gen_cpucaps should be replaced with ';' because it is
run under 'set -e' environment.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/r/20220227085232.206529-1-masahiroy@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>

arm64: Generate cpucaps.h

The arm64 code allocates an internal constant to every CPU feature it can
detect, distinct from the public hwcap numbers we use to expose some
features to userspace. Currently this is maintained manually which is an
irritating source of conflicts when working on new features, to avoid this
replace the header with a simple text file listing the names we've assigned
and sort it to minimise conflicts.

As part of doing this we also do the Kbuild hookup required to hook up
an arch tools directory and to generate header files in there.

This will result in a renumbering and reordering of the existing constants,
since they are all internal only the values should not be important. The
reordering will impact the order in which some steps in enumeration handle
features but the algorithm is not intended to depend on this and I haven't
seen any issues when testing. Due to the UAO cpucap having been removed in
the past we end up with ARM64_NCAPS being 1 smaller than it was before.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20210428121231.11219-1-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>