kbuild: make -Woverride-init warnings more consistent

The -Woverride-init warn about code that may be intentional or not,
but the inintentional ones tend to be real bugs, so there is a bit of
disagreement on whether this warning option should be enabled by default
and we have multiple settings in scripts/Makefile.extrawarn as well as
individual subsystems.

Older versions of clang only supported -Wno-initializer-overrides with
the same meaning as gcc's -Woverride-init, though all supported versions
now work with both. Because of this difference, an earlier cleanup of
mine accidentally turned the clang warning off for W=1 builds and only
left it on for W=2, while it's still enabled for gcc with W=1.

There is also one driver that only turns the warning off for newer
versions of gcc but not other compilers, and some but not all the
Makefiles still use a cc-disable-warning conditional that is no
longer needed with supported compilers here.

Address all of the above by removing the special cases for clang
and always turning the warning off unconditionally where it got
in the way, using the syntax that is supported by both compilers.

Fixes: 2cd3271b7a31 ("kbuild: avoid duplicate warning options")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Andrew Jeffery <andrew@codeconstruct.com.au>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

pinctrl: aspeed: Add AST2600 pinmux support

The AST2600 pinmux is fairly similar to the previous generations of
ASPEED BMC SoCs in terms of architecture, though differ in some of the
design details. The complexity of the pin expressions is largely reduced
(e.g. there are no-longer signals with multiple expressions muxing them
to the associated pin), and there are now signals and buses with
multiple pin groups.

The driver implements pinmux support for all 244 GPIO-capable pins plus
a further four pins that are not GPIO capable but which expose multiple
signals. pinconf will be implemented in a follow-up patch.

The implementation has been smoke-tested under qemu, and run on hardware
by ASPEED.

Debugged-by: Johnny Huang <johnny_huang@aspeedtech.com>
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Link: https://lore.kernel.org/r/20190711041942.23202-7-andrew@aj.id.au
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: aspeed: Split out pinmux from general pinctrl

ASPEED have completely rearranged the System Control Unit register
layout with the AST2600. The existing code took advantage of the fact
that the AST2400 and AST2500 had layouts that were similar enough to
have little impact on the pinmux infrastructure (though there is a wart
with read-modify-write vs write-1-clear semantics of the hardware
strapping registers between the two).

Given that any similarity has been thrown out with the AST2600, separate
out the function applying an expression state to be driver-specific.
With it, extract out the pinmux macro jungle to its own header and
implementation so the pieces can be composed without dependency cycles.

Cc: Johnny Huang <johnny_huang@aspeedtech.com>
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Link: https://lore.kernel.org/r/20190628023838.15426-8-andrew@aj.id.au
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

treewide: Add SPDX license identifier - Makefile/Kconfig

Add SPDX license identifiers to all Make/Kconfig files which:

- Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

pinctrl: aspeed: Wrap -Woverride-init with cc-option

Clang does not support this option:

warning: unknown warning option '-Woverride-init'; did you mean
'-Woverride-module'? [-Wunknown-warning-option]
1 warning generated.

Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Andrew Jeffery <andrew@aj.id.au>
Acked-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: Add pinctrl-aspeed-g5 driver

A small subset of pins and functions are exposed. The selection of pins
and functions is driven by the development of OpenBMC[1] on the
AST2500 SoC, particularly around booting the IBM Witherspoon platform.

[1] https://github.com/openbmc/docs

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: Add pinctrl-aspeed-g4 driver

A subset of the pins and functions are exposed. The selection of
functions and pins is driven by the development of OpenBMC[1] on the
AST2400 SoC, particularly around booting the OpenPOWER Palmetto
development machine.

[1] https://github.com/openbmc/docs

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: Add core support for Aspeed SoCs

The Aspeed SoCs typically provide more than 200 pins for GPIO and other
functions. The signal enabled on a pin is determined on a priority
basis, where a given pin can provide a number of different signal types.

In addition to the priority levels, the Aspeed pin controllers describe
the signal active on a pin by compound logical expressions involving
multiple operators, registers and bits. Some difficulty arises as a
pin's function bit masks for each priority level are frequently not the
same (i.e. we cannot just flip a bit to change from a high to low
priority signal), or even in the same register(s). Some configuration
bits affect multiple pins, while in other cases the signals for a bus
must each be enabled individually.

Together, these features give rise to some complexity in the
implementation. A more complete description of the complexities is
provided in the associated header file.

The patch doesn't implement pinctrl/pinmux/pinconf for any particular
Aspeed SoC, rather it adds the framework for defining pinmux
configurations.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>