pinctrl: aspeed-g6: Add AST2600 pinconf support

The AST2600 pinconf is a little different from previous generations of
ASPEED BMC SoCs in terms of architecture. The pull-down setting is
per-pin setting now, and drive-strength support 4 kind of value (e.g.
4ma, 8ma, 12ma, 16ma).

Signed-off-by: Johnny Huang <johnny_huang@aspeedtech.com>
[AJ: Trim unused pinctrl register macros]
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Link: https://lore.kernel.org/r/20191202061432.3996-8-andrew@aj.id.au
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: aspeed: Use masks to describe pinconf bitfields

Since some of the AST2600 pinconf setting are not just single bit, modified
aspeed_pin_config @bit to @mask and add @mask to aspeed_pin_config_map to
support configuring multiple bits.

Signed-off-by: Johnny Huang <johnny_huang@aspeedtech.com>
[AJ: Tweak commit message]
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Link: https://lore.kernel.org/r/20191202061432.3996-7-andrew@aj.id.au
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: aspeed: Move aspeed_pin_config_map to separate source file

The AST2600 pinconf differs from the 2400 and 2500, aspeed_pin_config_map
should define separately, and add @confmaps and @nconfmaps to
aspeed_pinctrl_data structure for that change.

Signed-off-by: Johnny Huang <johnny_huang@aspeedtech.com>
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Link: https://lore.kernel.org/r/20191202061432.3996-6-andrew@aj.id.au
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: aspeed: Add ASPEED_SB_PINCONF() helper

This helper macro is for declaring single bit (SB) mask pinconf,
and is used to prepare for modifying aspeed_pin_config
structure, the aspeed_pin_config structure @bit variable will be
modified to @mask.

This case is common in the AST2400/AST2500 which the mask is a single bit.

Signed-off-by: Johnny Huang <johnny_huang@aspeedtech.com>
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Link: https://lore.kernel.org/r/20191202061432.3996-5-andrew@aj.id.au
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: aspeed: Strip moved macros and structs from private header

Further cleanup from the SPDX fixup fallout for the recent ASPEED
series. aspeed_g4_defconfig, aspeed_g5_defconfig and multi_v5_defconfig
now compile. Smoke tested the g4 and g5 kernels under QEMU's
palmetto-bmc and romulus-bmc machines respectively.

Fixes: 35d8510ea3ad ("pinctrl: aspeed: Fix missed include")
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Link: https://lore.kernel.org/r/20190710032216.4088-1-andrew@aj.id.au
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: aspeed: Fix missed include

Some SPDX churn made my fixes drop an important include
from the Aspeed pinctrl header. Fix it up.

Cc: Andrew Jeffery <andrew@aj.id.au>
Reported-by: Andrew Jeffery <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>

pinctrl: aspeed: Correct comment that is no longer true

We have handled the GFX register case for quite some time now.

Cc: Johnny Huang <johnny_huang@aspeedtech.com>
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Acked-by: Joel Stanley <joel@jms.id.au>
Link: https://lore.kernel.org/r/20190628023838.15426-6-andrew@aj.id.au
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

pinctrl: aspeed: Fix ast2500 strap register write logic

On AST2500, the hardware strap register(SCU70) only accepts write ‘1’,
to clear it to ‘0’, must set bits(write ‘1’) to SCU7C

Signed-off-by: Yong Li <sdliyong@gmail.com>
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Tested-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: aspeed: Add core pinconf support

Several pinconf parameters have a fairly straight-forward mapping onto
the Aspeed pin controller. These include management of pull-down bias,
drive-strength, and some debounce configuration.

Pin biasing largely is managed on a per-GPIO-bank basis, aside from the
ADC and RMII/RGMII pins. As the bias configuration for each pin in a
bank maps onto a single per-bank bit, configuration tables will be
introduced to describe the ranges of pins and the supported pinconf
parameter. The use of tables also helps with the sparse support of
pinconf properties, and the fact that not all GPIO banks support
biasing or drive-strength configuration.

Further, as the pin controller uses a consistent approach for bias and
drive strength configuration at the register level, a second table is
defined for looking up the the bit-state required to enable or query the
provided configuration.

Testing for pinctrl-aspeed-g4 was performed on an OpenPOWER Palmetto
system, and pinctrl-aspeed-g5 on an AST2500EVB as well as under QEMU.
The test method was to set the appropriate bits via devmem and verify
the result through the controller's pinconf-pins debugfs file. This
simultaneously validates the get() path and half of the set() path. The
remainder of the set() path was validated by configuring a handful of
pins via the devicetree with the supported pinconf properties and
verifying the appropriate registers were touched.

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

pinctrl: aspeed-g5: Add mux configuration for all pins

The patch introducing the g5 pinctrl driver implemented a smattering of
pins to flesh out the implementation of the core and provide bare-bones
support for some OpenPOWER platforms and the AST2500 evaluation board.
Now, update the bindings document to reflect the complete functionality
and implement the necessary pin configuration tables in the driver.

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

pinctrl: aspeed: Read and write bits in LPC and GFX controllers

The System Control Unit IP block in the Aspeed SoCs is typically where
the pinmux configuration is found, but not always. A number of pins
depend on state in one of LPC Host Control (LHC) or SoC Display
Controller (GFX) IP blocks, so the Aspeed pinmux drivers should have the
means to adjust these as necessary.

We use syscon to cast a regmap over the GFX and LPC blocks, which is
used as an arbitration layer between the relevant driver and the pinctrl
subsystem. The regmaps are then exposed to the SoC-specific pinctrl
drivers by phandles in the devicetree, and are selected during a mux
request by querying a new 'ip' member in struct aspeed_sig_desc.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Acked-by: Rob Herring <robh@kernel.org>
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>