clk: renesas: cpg-mssr: Add support for R-Car V4M

Initial CPG support for the R-Car V4M (R8A779H0).

Signed-off-by: Cong Dang <cong.dang.xn@renesas.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Link: https://lore.kernel.org/r/c678ef7164e3777fa91572f72e47ef385cea64b8.1706194617.git.geert+renesas@glider.be

clk: renesas: cpg-mssr: Ignore all clocks assigned to non-Linux system

Some boards might use Linux and another OS at the same time. In such
case, currently, during booting, Linux will stop necessary module clocks
which are not used on the Linux side, but are used by another OS.

To avoid such situation, renesas-cpg-mssr tries to find
status = "reserved" devices (A), and adds CLK_IGNORE_UNUSED flag to its
<&cgp CPG_MOD xxx> clock (B).

Table 2.4: Values for status property
https://github.com/devicetree-org/devicetree-specification/releases/download/v0.4/devicetree-specification-v0.4.pdf

"reserved"
Indicates that the device is operational, but should not be
used. Typically this is used for devices that are controlled
by another software component, such as platform firmware.

ex)
scif5: serial@e6f30000 {
...
(B) clocks = <&cpg CPG_MOD 202>,
<&cpg CPG_CORE R8A7795_CLK_S3D1>,
<&scif_clk>;
...
(A) status = "reserved";
};

Cc: Aymeric Aillet <aymeric.aillet@iot.bzh>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Tested-by: Yusuke Goda <yusuke.goda.sx@renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/878r4ygfap.wl-kuninori.morimoto.gx@renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: Explicitly include correct DT includes

The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it as merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.

Acked-by: Dinh Nguyen <dinguyen@kernel.org>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> # samsung
Acked-by: Heiko Stuebner <heiko@sntech.de> #rockchip
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> # versaclock5
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230718143156.1066339-1-robh@kernel.org
Acked-by: Abel Vesa <abel.vesa@linaro.org> #imx
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: renesas: cpg-mssr: Convert to readl_poll_timeout_atomic()

Use readl_poll_timeout_atomic() instead of open-coding the same
operation.

As typically no retries are needed, 10 µs is a suitable timeout value.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/832d29fd9aa3239ea949535309d2bdb003d40c9e.1685692810.git.geert+renesas@glider.be

clk: renesas: cpg-mssr: Update MSSR register range for R-Car V4H

The SRCR, SRSTCLR, MSTPCR and MSTPSR registers for R-Car V4H (R8A779G0)
each have registers up to offset 0x74.
Update the corresponding arrays.

Signed-off-by: Takeshi Kihara <takeshi.kihara.df@renesas.com>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/87a61wanfx.wl-kuninori.morimoto.gx@renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: remove MODULE_LICENSE in non-modules

Since commit 8b41fc4454e ("kbuild: create modules.builtin without
Makefile.modbuiltin or tristate.conf"), MODULE_LICENSE declarations
are used to identify modules. As a consequence, uses of the macro
in non-modules will cause modprobe to misidentify their containing
object file as a module when it is not (false positives), and modprobe
might succeed rather than failing with a suitable error message.

So remove it in the files in this commit, none of which can be built as
modules.

Signed-off-by: Nick Alcock <nick.alcock@oracle.com>
Suggested-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: linux-modules@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Hitomi Hasegawa <hasegawa-hitomi@fujitsu.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: linux-renesas-soc@vger.kernel.org
Cc: linux-clk@vger.kernel.org
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>

clk: renesas: rcar-gen3: Disable R-Car H3 ES1.*

R-Car H3 ES1.* was only available to an internal development group and
needed a lot of quirks and workarounds. These become a maintenance
burden now, so our development group decided to remove upstream support
for this SoC. Public users only have ES2 onwards.

In addition to the ES1 specific removals, a check for it was added
preventing the machine to boot further. It may otherwise inherit wrong
clock settings from ES2 which could damage the hardware.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20230202092332.2504-1-wsa+renesas@sang-engineering.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Remove superfluous check in resume code

When the code flow arrives at printing the error message in
cpg_mssr_resume_noirq(), we know for sure that we are not running on an
RZ/A Soc, as the code checked for that before.

Fixes: ace342097768e35f ("clk: renesas: cpg-mssr: Fix STBCR suspend/resume handling")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/144a3e66d748c0c17f3524ac8fa6ece5bf5b6f1e.1673425314.git.geert+renesas@glider.be

clk: renesas: cpg-mssr: Fix use after free if cpg_mssr_common_init() failed

If cpg_mssr_common_init() fails after assigning priv to global variable
cpg_mssr_priv, it deallocates priv, but cpg_mssr_priv keeps dangling
pointer that potentially can be used later.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 1f7db7bbf031 ("clk: renesas: cpg-mssr: Add early clock support")
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/1671806417-32623-1-git-send-email-khoroshilov@ispras.ru
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Add support for R-Car V4H

Initial CPG support for R-Car V4H (r8a779g0).

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20220428135058.597586-2-yoshihiro.shimoda.uh@renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Add support for R-Car S4-8

Initial CPG support for R-Car S4-8 (r8a779f0).

Inspired by patches in the BSP by LUU HOAI.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20211201073308.1003945-10-yoshihiro.shimoda.uh@renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: rcar-gen4: Introduce R-Car Gen4 CPG driver

According to the official website [1], the R-Car V3U SoC is based
on the R-Car Gen4 architecture. So, introduce R-Car Gen4 CPG
driver.

[1]
https://www.renesas.com/us/en/products/automotive-products/automotive-system-chips-socs/r-car-v3u-best-class-r-car-v3u-asil-d-system-chip-automated-driving

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20211201073308.1003945-9-yoshihiro.shimoda.uh@renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: propagate return value of_genpd_add_provider_simple()

of_genpd_add_provider_simple() might fail, this patch makes sure we check
the return value of of_genpd_add_provider_simple() by propagating the
return value to the caller of cpg_mssr_add_clk_domain().

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Link: https://lore.kernel.org/r/20211117115101.28281-5-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Check return value of pm_genpd_init()

Make sure we check the return value of pm_genpd_init() which might fail.
Also add a devres action to remove the power-domain in-case the probe
callback fails further down in the code flow.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Link: https://lore.kernel.org/r/20211117115101.28281-4-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Make srstclr[] comment block consistent

Make the style of the comment block for the Software Reset Clearing
Register offsets consistent with the comment blocks for the other
register offsets.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lore.kernel.org/r/97dde75fe3ff27b9639c59a43cddbd9d5c405d0c.1620119700.git.geert+renesas@glider.be

clk: renesas: cpg-mssr: Remove unused [RM]MSTPCR() definitions

The Realtime Module Stop Control Register definitions (RMSTPCR(i)) are
incorrect for i >= 8 on R-Car Gen2 and Gen3.

As these are unused, and not planned to be used, just like the
corresponding Modem Module Stop Control Register definitions (MMSTPCR())
on R-Mobile APE6 (they are intended for the software running on the
Real-Time and Modem CPU cores), they can just be removed.

Reported-by: Hai Nguyen Pham <hai.pham.ud@renesas.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lore.kernel.org/r/2d8bc4d9806b419ebb06030d2f31b2ea1e59b1d6.1620119700.git.geert+renesas@glider.be

clk: renesas: Zero init clk_init_data

As clk_core_populate_parent_map() checks clk_init_data.num_parents
first, and checks clk_init_data.parent_names[] before
clk_init_data.parent_data[] and clk_init_data.parent_hws[], leaving the
latter uninitialized doesn't do harm for now. However, it is better to
play it safe, and initialize all clk_init_data structures to zeroes, to
avoid any current and future members containing uninitialized data.

Remove a few explicit zero initializers, which are now superfluous.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lore.kernel.org/r/20210326105434.1574796-1-geert+renesas@glider.be

clk: renesas: cpg-mssr: Fix formatting issues for 'smstpcr_saved's documentation

Fixes the following W=1 kernel build warning(s):

drivers/clk/renesas/renesas-cpg-mssr.c:168: warning: Function parameter or member 'smstpcr_saved' not described in 'cpg_mssr_priv'

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20210126124540.3320214-12-lee.jones@linaro.org
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: fix kerneldoc of cpg_mssr_priv

The struct cpg_mssr_priv missed proper formatting:

drivers/clk/renesas/renesas-cpg-mssr.c:142: warning:
cannot understand function prototype: 'struct cpg_mssr_priv '

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20201103162435.13689-7-krzk@kernel.org
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Add support for R-Car V3U

Initial support for R-Car V3U (r8a779a0), including core, module
clocks, resets, and register access, because register specification
differs from R-Car Gen2/3.

Inspired by patches in the BSP by LUU HOAI.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/1599810232-29035-4-git-send-email-yoshihiro.shimoda.uh@renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Add register pointers into struct cpg_mssr_priv

To support other register layouts in the future, add register pointers
of {control,status,reset,reset_clear}_regs into struct cpg_mssr_priv.
After that, we can remove unused macros like MSTPSR(). No behavioral
changes.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/1599810232-29035-3-git-send-email-yoshihiro.shimoda.uh@renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Use enum clk_reg_layout instead of a boolean flag

Geert suggested defining multiple register layout variants using an enum
[1] to support further devices like R-Car V3U. So, use enum
clk_reg_layout instead of a boolean .stbyctrl flag. No behavioral
change.

[1] https://lore.kernel.org/linux-renesas-soc/CAMuHMdVAgN69p9FFnQdO4iHk2CHkeNaVui2Q-FOY6_BFVjQ-Nw@mail.gmail.com/

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/1599810232-29035-2-git-send-email-yoshihiro.shimoda.uh@renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Add r8a774e1 support

Add support for the RZ/G2H (R8A774E1) SoC to the Renesas Clock
Pulse Generator / Module Standby and Software Reset driver.

Signed-off-by: Marian-Cristian Rotariu <marian-cristian.rotariu.rb@bp.renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Link: https://lore.kernel.org/r/1594138692-16816-11-git-send-email-prabhakar.mahadev-lad.rj@bp.renesas.com
[geert: Mark RWDT critical, cfr. commit f23f1101ad0ef1ac ("clk: renesas: rcar-gen3: Mark RWDT clocks as critical")]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Mark clocks as critical only if on at boot

This allows us to add the RWDT clock to the list of critical clocks without
keeping it enabled needlessly if not used.

Changing the semantics of crit_mod_clks in this way is safe for the current
user (INTC-AP) because it is never off at boot time.

Signed-off-by: Ulrich Hecht <uli+renesas@fpond.eu>
Link: https://lore.kernel.org/r/20200616162626.27944-2-uli+renesas@fpond.eu
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Fix STBCR suspend/resume handling

On SoCs with Standby Control Registers (STBCRs) instead of Module Stop
Control Registers (MSTPCRs), the suspend handler saves the wrong
registers, and the resume handler prints the wrong register in an error
message.

Fortunately this cannot happen yet, as the suspend/resume code is used
on PSCI systems only, and systems with STBCRs (RZ/A1 and RZ/A2) do not
use PSCI. Still, it is better to fix this, to avoid this becoming a
problem in the future.

Distinguish between STBCRs and MSTPCRs where needed. Replace the
useless printing of the virtual register address in the resume error
message by printing the register index.

Fixes: fde35c9c7db5732c ("clk: renesas: cpg-mssr: Add R7S9210 support")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200507074713.30113-1-geert+renesas@glider.be

clk: renesas: cpg-mssr: Add R8A7742 support

Add RZ/G1H (R8A7742) Clock Pulse Generator / Module Standby and Software
Reset support, using the CPG/MSSR driver core and the common R-Car Gen2
(and RZ/G) code.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Marian-Cristian Rotariu <marian-cristian.rotariu.rb@bp.renesas.com>
Link: https://lore.kernel.org/r/1587998460-7804-1-git-send-email-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: r8a7796: Add R8A77961 CPG/MSSR support

Add support for the R-Car M3-W+ (R8A77961) SoC to the Renesas Clock
Pulse Generator / Module Standby and Software Reset driver.

R-Car M3-W+ is very similar to R-Car M3-W (R8A77960), which allows for
both SoCs to share a driver. R-Car M3-W+ lacks a few modules, so their
clocks must be nullified.

Based on a patch in the BSP by Takeshi Kihara
<takeshi.kihara.df@renesas.com>.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20191023122941.12342-5-geert+renesas@glider.be

clk: renesas: Rename CLK_R8A7796 to CLK_R8A77960

Rename CONFIG_CLK_R8A7796 for R-Car M3-W (R8A77960) to
CONFIG_CLK_R8A77960, to avoid confusion with R-Car M3-W+ (R8A77961),
which will use CONFIG_CLK_R8A77961.

Extend the dependency of CONFIG_CLK_R8A77960 from CONFIG_ARCH_R8A7796 to
CONFIG_ARCH_R8A77960, to relax dependencies for a future rename of the
SoC configuration symbol.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20191023122941.12342-4-geert+renesas@glider.be

clk: renesas: cpg-mssr: Add r8a774b1 support

Add RZ/G2N (R8A774B1) Clock Pulse Generator / Module Standby and Software
Reset support.

Based on the Table 8.4d of "RZ/G Series, 2nd Generation User's Manual:
Hardware (Rev. 0.80, May 2019)".

Signed-off-by: Biju Das <biju.das@bp.renesas.com>
Link: https://lore.kernel.org/r/1568881036-4404-7-git-send-email-biju.das@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Set GENPD_FLAG_ALWAYS_ON for clock domain

The CPG/MSSR Clock Domain driver does not implement the
generic_pm_domain.power_{on,off}() callbacks, as the domain itself
cannot be powered down. Hence the domain should be marked as always-on
by setting the GENPD_FLAG_ALWAYS_ON flag, to prevent the core PM Domain
code from considering it for power-off, and doing unnessary processing.

Note that this only affects RZ/A2 SoCs. On R-Car Gen2 and Gen3 SoCs,
the R-Car SYSC driver handles Clock Domain creation, and offloads only
device attachment/detachment to the CPG/MSSR driver.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>

clk: renesas: cpg-mssr: Fix reset control race condition

The module reset code in the Renesas CPG/MSSR driver uses
read-modify-write (RMW) operations to write to a Software Reset Register
(SRCRn), and simple writes to write to a Software Reset Clearing
Register (SRSTCLRn), as was mandated by the R-Car Gen2 and Gen3 Hardware
User's Manuals.

However, this may cause a race condition when two devices are reset in
parallel: if the reset for device A completes in the middle of the RMW
operation for device B, device A may be reset again, causing subtle
failures (e.g. i2c timeouts):

thread A thread B
-------- --------

val = SRCRn
val |= bit A
SRCRn = val

delay

val = SRCRn (bit A is set)

SRSTCLRn = bit A
(bit A in SRCRn is cleared)

val |= bit B
SRCRn = val (bit A and B are set)

This can be reproduced on e.g. Salvator-XS using:

$ while true; do i2cdump -f -y 4 0x6A b > /dev/null; done &
$ while true; do i2cdump -f -y 2 0x10 b > /dev/null; done &

i2c-rcar e6510000.i2c: error -110 : 40000002
i2c-rcar e66d8000.i2c: error -110 : 40000002

According to the R-Car Gen3 Hardware Manual Errata for Rev.
0.80 of Feb 28, 2018, reflected in Rev. 1.00 of the R-Car Gen3 Hardware
User's Manual, writes to SRCRn do not require read-modify-write cycles.

Note that the R-Car Gen2 Hardware User's Manual has not been updated
yet, and still says a read-modify-write sequence is required. According
to the hardware team, the reset hardware block is the same on both R-Car
Gen2 and Gen3, though.

Hence fix the issue by replacing the read-modify-write operations on
SRCRn by simple writes.

Reported-by: Yao Lihua <Lihua.Yao@desay-svautomotive.com>
Fixes: 6197aa65c4905532 ("clk: renesas: cpg-mssr: Add support for reset control")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Linh Phung <linh.phung.jy@renesas.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: renesas: cpg-mssr: Use [] to denote a flexible array member

Flexible array members should be denoted using [] instead of [0], else
gcc will not warn when they are no longer at the end of the structure.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>

clk: renesas: cpg-mssr: Combine driver-private and clock array allocation

Make cpg_mssr_priv.clks[] a flexible array member, and use the new
struct_size() helper, to combine the allocation of the driver-private
structure and array of available clocks.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>

clk: renesas: cpg-mssr: Update kerneldoc for struct cpg_mssr_priv

New fields were added, but kerneldoc was forgotten, or inserted at the
wrong place.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>

clk: renesas: cpg-mssr: Remove error messages on out-of-memory conditions

pm_clk_create() and pm_clk_add_clk() can fail only when running out of
memory. Hence there is no need to print error messages on failure, as
the memory allocation core already takes care of that.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>

clk: renesas: cpg-mssr: Use genpd of_node instead of local copy

Since commit 6a0ae73d95956f7e ("PM / Domain: Add support to parse
domain's OPP table"), of_genpd_add_provider_simple() fills in
the dev.of_node field in the generic_pm_domain structure.

Hence cpg_mssr_is_pm_clk() can use that instead of its own copy in the
driver-private cpg_mssr_clk_domain structure.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>

clk: Remove io.h from clk-provider.h

Now that we've gotten rid of clk_readl() we can remove io.h from the
clk-provider header and push out the io.h include to any code that isn't
already including the io.h header but using things like readl/writel,
etc.

Found with this grep:

git grep -l clk-provider.h | grep '.c$' | xargs git grep -L 'linux/io.h' | \
xargs git grep -l \
-e '\<__iowrite32_copy\>' --or \
-e '\<__ioread32_copy\>' --or \
-e '\<__iowrite64_copy\>' --or \
-e '\<ioremap_page_range\>' --or \
-e '\<ioremap_huge_init\>' --or \
-e '\<arch_ioremap_pud_supported\>' --or \
-e '\<arch_ioremap_pmd_supported\>' --or \
-e '\<devm_ioport_map\>' --or \
-e '\<devm_ioport_unmap\>' --or \
-e '\<IOMEM_ERR_PTR\>' --or \
-e '\<devm_ioremap\>' --or \
-e '\<devm_ioremap_nocache\>' --or \
-e '\<devm_ioremap_wc\>' --or \
-e '\<devm_iounmap\>' --or \
-e '\<devm_ioremap_release\>' --or \
-e '\<devm_memremap\>' --or \
-e '\<devm_memunmap\>' --or \
-e '\<__devm_memremap_pages\>' --or \
-e '\<pci_remap_cfgspace\>' --or \
-e '\<arch_has_dev_port\>' --or \
-e '\<arch_phys_wc_add\>' --or \
-e '\<arch_phys_wc_del\>' --or \
-e '\<memremap\>' --or \
-e '\<memunmap\>' --or \
-e '\<arch_io_reserve_memtype_wc\>' --or \
-e '\<arch_io_free_memtype_wc\>' --or \
-e '\<__io_aw\>' --or \
-e '\<__io_pbw\>' --or \
-e '\<__io_paw\>' --or \
-e '\<__io_pbr\>' --or \
-e '\<__io_par\>' --or \
-e '\<__raw_readb\>' --or \
-e '\<__raw_readw\>' --or \
-e '\<__raw_readl\>' --or \
-e '\<__raw_readq\>' --or \
-e '\<__raw_writeb\>' --or \
-e '\<__raw_writew\>' --or \
-e '\<__raw_writel\>' --or \
-e '\<__raw_writeq\>' --or \
-e '\<readb\>' --or \
-e '\<readw\>' --or \
-e '\<readl\>' --or \
-e '\<readq\>' --or \
-e '\<writeb\>' --or \
-e '\<writew\>' --or \
-e '\<writel\>' --or \
-e '\<writeq\>' --or \
-e '\<readb_relaxed\>' --or \
-e '\<readw_relaxed\>' --or \
-e '\<readl_relaxed\>' --or \
-e '\<readq_relaxed\>' --or \
-e '\<writeb_relaxed\>' --or \
-e '\<writew_relaxed\>' --or \
-e '\<writel_relaxed\>' --or \
-e '\<writeq_relaxed\>' --or \
-e '\<readsb\>' --or \
-e '\<readsw\>' --or \
-e '\<readsl\>' --or \
-e '\<readsq\>' --or \
-e '\<writesb\>' --or \
-e '\<writesw\>' --or \
-e '\<writesl\>' --or \
-e '\<writesq\>' --or \
-e '\<inb\>' --or \
-e '\<inw\>' --or \
-e '\<inl\>' --or \
-e '\<outb\>' --or \
-e '\<outw\>' --or \
-e '\<outl\>' --or \
-e '\<inb_p\>' --or \
-e '\<inw_p\>' --or \
-e '\<inl_p\>' --or \
-e '\<outb_p\>' --or \
-e '\<outw_p\>' --or \
-e '\<outl_p\>' --or \
-e '\<insb\>' --or \
-e '\<insw\>' --or \
-e '\<insl\>' --or \
-e '\<outsb\>' --or \
-e '\<outsw\>' --or \
-e '\<outsl\>' --or \
-e '\<insb_p\>' --or \
-e '\<insw_p\>' --or \
-e '\<insl_p\>' --or \
-e '\<outsb_p\>' --or \
-e '\<outsw_p\>' --or \
-e '\<outsl_p\>' --or \
-e '\<ioread8\>' --or \
-e '\<ioread16\>' --or \
-e '\<ioread32\>' --or \
-e '\<ioread64\>' --or \
-e '\<iowrite8\>' --or \
-e '\<iowrite16\>' --or \
-e '\<iowrite32\>' --or \
-e '\<iowrite64\>' --or \
-e '\<ioread16be\>' --or \
-e '\<ioread32be\>' --or \
-e '\<ioread64be\>' --or \
-e '\<iowrite16be\>' --or \
-e '\<iowrite32be\>' --or \
-e '\<iowrite64be\>' --or \
-e '\<ioread8_rep\>' --or \
-e '\<ioread16_rep\>' --or \
-e '\<ioread32_rep\>' --or \
-e '\<ioread64_rep\>' --or \
-e '\<iowrite8_rep\>' --or \
-e '\<iowrite16_rep\>' --or \
-e '\<iowrite32_rep\>' --or \
-e '\<iowrite64_rep\>' --or \
-e '\<__io_virt\>' --or \
-e '\<pci_iounmap\>' --or \
-e '\<virt_to_phys\>' --or \
-e '\<phys_to_virt\>' --or \
-e '\<ioremap_uc\>' --or \
-e '\<ioremap\>' --or \
-e '\<__ioremap\>' --or \
-e '\<iounmap\>' --or \
-e '\<ioremap\>' --or \
-e '\<ioremap_nocache\>' --or \
-e '\<ioremap_uc\>' --or \
-e '\<ioremap_wc\>' --or \
-e '\<ioremap_wc\>' --or \
-e '\<ioremap_wt\>' --or \
-e '\<ioport_map\>' --or \
-e '\<ioport_unmap\>' --or \
-e '\<ioport_map\>' --or \
-e '\<ioport_unmap\>' --or \
-e '\<xlate_dev_kmem_ptr\>' --or \
-e '\<xlate_dev_mem_ptr\>' --or \
-e '\<unxlate_dev_mem_ptr\>' --or \
-e '\<virt_to_bus\>' --or \
-e '\<bus_to_virt\>' --or \
-e '\<memset_io\>' --or \
-e '\<memcpy_fromio\>' --or \
-e '\<memcpy_toio\>'

I also reordered a couple includes when they weren't alphabetical and
removed clk.h from kona, replacing it with clk-provider.h because
that driver doesn't use clk consumer APIs.

Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Chen-Yu Tsai <wens@csie.org>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Acked-by: Tero Kristo <t-kristo@ti.com>
Acked-by: Sekhar Nori <nsekhar@ti.com>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Mark Brown <broonie@kernel.org>
Cc: Chris Zankel <chris@zankel.net>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Acked-by: John Crispin <john@phrozen.org>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: renesas: Remove usage of CLK_IS_BASIC

This flag doesn't look to be used by any code, just set in various clk
init structures and then never tested again. Remove it from these
drivers as it doesn't provide any benefit.

Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: <linux-renesas-soc@vger.kernel.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: renesas: cpg-mssr: Add early clock support

Add support for SoCs that need to register core and module clocks early in
order to use OF drivers that exclusively use macros such as
TIMER_OF_DECLARE.

Signed-off-by: Chris Brandt <chris.brandt@renesas.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Add r8a774c0 support

Add RZ/G2E (R8A774C0) Clock Pulse Generator / Module Standby and
Software Reset support.

Based on Table 8.2g of "RZ/G Series, 2nd Generation User's Manual:
Hardware (Rev. 0.61, June 12, 2018)".

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Reviewed-by: Biju Das <biju.das@bp.renesas.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: r8a7743: Add r8a7744 support

Add RZ/G1N (R8A7744) Clock Pulse Generator / Module Standby and Software
Reset support.

Signed-off-by: Biju Das <biju.das@bp.renesas.com>
Reviewed-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Add R7S9210 support

Add support for the R7S9210 (RZ/A2) Clock Pulse Generator and Module
Standby.

The Module Standby HW in the RZ/A series is very close to R-Car HW, except
for how the registers are laid out.
The MSTP registers are only 8-bits wide, there are no status registers
(MSTPSR), and the register offsets are a little different. Since the RZ/A
hardware manuals refer to these registers as the Standby Control Registers,
we'll use that name to distinguish the RZ/A type from the R-Car type.

Signed-off-by: Chris Brandt <chris.brandt@renesas.com>
Acked-by: Rob Herring <robh@kernel.org> # DT bits
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: use SPDX identifier for Renesas drivers

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: renesas: cpg-mssr: Add r8a774a1 support

Add RZ/G2M (R8A774A1) Clock Pulse Generator / Module Standby and Software
Reset support.

Based on the Table 8.2b of "RZ/G Series, 2nd Generation User's Manual:
Hardware ((Rev. 0.61, June 12, 2018)".

Signed-off-by: Biju Das <biju.das@bp.renesas.com>
Reviewed-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Add support for fixed rate clocks

Add support for defining fixed rate clocks, to be used for on-chip
oscillators.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>

clk: renesas: cpg-mssr: Stop using printk format %pCr

Printk format "%pCr" will be removed soon, as clk_get_rate() must not be
called in atomic context.

Replace it by open-coding the operation. This is safe here, as the code
runs in task context.

Link: http://lkml.kernel.org/r/1527845302-12159-2-git-send-email-geert+renesas@glider.be
To: Jia-Ju Bai <baijiaju1990@gmail.com>
To: Jonathan Corbet <corbet@lwn.net>
To: Michael Turquette <mturquette@baylibre.com>
To: Stephen Boyd <sboyd@kernel.org>
To: Zhang Rui <rui.zhang@intel.com>
To: Eduardo Valentin <edubezval@gmail.com>
To: Eric Anholt <eric@anholt.net>
To: Stefan Wahren <stefan.wahren@i2se.com>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-doc@vger.kernel.org
Cc: linux-clk@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: linux-serial@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-renesas-soc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: stable@vger.kernel.org # 4.5+
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Petr Mladek <pmladek@suse.com>

clk: renesas: cpg-mssr: Add support for R-Car E3

Initial support for R-Car E3 (r8a77990), including core and module
clocks.

Based on the Table 8.2g of "R-Car Series, 3rd Generation User's Manual:
Hardware ((Rev. 0.80, Oct 31, 2017) with Manual Errata on Feb. 28, 2018".

Inspried by patches by Takeshi Kihara in the BSP.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Add r8a77470 support

Add RZ/G1C (R8A77470) Clock Pulse Generator / Module Standby and Software
Reset support.

Signed-off-by: Biju Das <biju.das@bp.renesas.com>
Reviewed-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Adjust r8a77980 ifdef

Adjust the R8A77980-specific #ifdefs to use CLK instead of ARCH
to follow same style as other SoCs.

Fixes: ce15783c510a9905 ("clk: renesas: cpg-mssr: add R8A77980 support")
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Add support for R-Car M3-N

Initial support for R-Car M3-N (r8a77965), including core and module
clocks.

Based on Table 8.2d of "R-Car Series, 3rd Generation User's Manual:
Hardware (Rev. 0.80, Oct 31, 2017)".

Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: add R8A77980 support

Add R-Car V3H (R8A77980) Clock Pulse Generator / Module Standby and
Software Reset support, using the CPG/MSSR driver core and the common
R-Car Gen3 code.

Based on the original (and large) patch by Vladimir Barinov.

Signed-off-by: Vladimir Barinov <vladimir.barinov@cogentembedded.com>
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Keep wakeup sources active during system suspend

If a device is part of the CPG/MSSR Clock Domain and to be used as a
wakeup source, it must be kept active during system suspend.

Currently this is handled in device-specific drivers by explicitly
increasing the use count of the module clock when the device is
configured as a wakeup source. However, the proper way to prevent the
device from being stopped is to inform this requirement to the genpd
core, by setting the GENPD_FLAG_ACTIVE_WAKEUP flag.

Note that this will only affect devices configured as wakeup sources.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>

clk: renesas: div6: Restore clock state during resume

On R-Car Gen3 systems, PSCI system suspend powers down the SoC, losing
clock configuration. Register an (optional) notifier to restore the
DIV6 clock state during system resume.

As DIV6 clocks can be picky w.r.t. modifying multiple register fields at
once, restore is not implemented by blindly restoring the register
value, but by using the existing cpg_div6_clock_{en,dis}able() helpers.

Note that this does not yet support DIV6 clocks with multiple parents,
which do not exist on R-Car Gen3 SoCs.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>

clk: renesas: cpg-mssr: Add support to restore core clocks during resume

On R-Car Gen3 systems, PSCI system suspend powers down the SoC, possibly
losing clock configuration. Hence add a notifier chain that can be used
by core clocks to save/restore clock state during system suspend/resume.

The implementation of the actual clock state save/restore operations is
clock-specific, and to be registered with the notifier chain in the SoC
or family-specific cpg_mssr_info.cpg_clk_register() callback.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>

clk: renesas: cpg-mssr: Restore module clocks during resume

During PSCI system suspend, R-Car Gen3 SoCs are powered down, and their
clock register state is lost. Note that as the boot loader skips most
initialization after system resume, clock register state differs from
the state encountered during normal system boot, too.

Hence after s2ram, some operations may fail because module clocks are
disabled, while drivers expect them to be still enabled. E.g. EtherAVB
fails when Wake-on-LAN has been enabled using "ethtool -s eth0 wol g":

ravb e6800000.ethernet eth0: failed to switch device to config mode
ravb e6800000.ethernet eth0: device will be stopped after h/w processes are done.
ravb e6800000.ethernet eth0: failed to switch device to config
PM: Device e6800000.ethernet failed to resume: error -110

In addition, some module clocks that were disabled by
clk_disable_unused() may have been re-enabled, wasting power.

To fix this, restore all bits of the SMSTPCR registers that represent
clocks under control of Linux.

Notes:
- While this fixes EtherAVB operation after resume from s2ram,
EtherAVB cannot be used as an actual wake-up source from s2ram, only
from s2idle, due to PSCI limitations,
- To avoid overhead on platforms not needing it, the suspend/resume
code has a build time dependency on sleep and PSCI support, and a
runtime dependency on PSCI.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>

clk: renesas: cpg-mssr: Add R8A77970 support

Add R-Car V3M (R8A77970) Clock Pulse Generator / Module Standby and
Software Reset support, using the CPG/MSSR driver core and the common
R-Car Gen3 code.

Based on the original (and large) patch by Daisuke Matsushita
<daisuke.matsushita.ns@hitachi.com>.

Signed-off-by: Vladimir Barinov <vladimir.barinov@cogentembedded.com>
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Add R8A77995 support

Add R-Car D3 (R8A77995) Clock Pulse Generator / Module Standby and
Software Reset support, using the CPG/MSSR driver core and the common
R-Car Gen3 CPG code.

Based on the R-Car Series, 3rd Generation Hardware User's Manual, Rev.
0.55, Jun. 30, 2017.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Rob Herring <robh@kernel.org>

clk: renesas: cpg-mssr: Use of_device_get_match_data() helper

If CONFIG_OF=n:

drivers/clk/renesas/renesas-cpg-mssr.c: In function ‘cpg_mssr_probe’:
drivers/clk/renesas/renesas-cpg-mssr.c:702: warning: dereferencing ‘void *’ pointer
drivers/clk/renesas/renesas-cpg-mssr.c:702: error: request for member ‘data’ in something not a structure or union

To fix this, use the of_device_get_match_data() helper, for which a
dummy version is provided if CONFIG_OF=n.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: renesas: r8a7794: Add new CPG/MSSR driver

Add a new R-Car E2 Clock Pulse Generator / Module Standby and Software
Reset driver, using the CPG/MSSR driver core. This will enable support
for module resets, which are not supported by the existing driver.

The old driver can still be used through a Kconfig option, to preserve
backward compatibility with old DTBs.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: r8a7792: Add new CPG/MSSR driver

Add a new R-Car V2H Clock Pulse Generator / Module Standby and Software
Reset driver, using the CPG/MSSR driver core. This will enable support
for module resets, which are not supported by the existing driver.

The old driver can still be used through a Kconfig option, to preserve
backward compatibility with old DTBs.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: r8a7791/r8a7793: Add new CPG/MSSR driver

Add a new R-Car M2-W/N Clock Pulse Generator / Module Standby and
Software Reset driver, using the CPG/MSSR driver core. This will enable
support for module resets, which are not supported by the existing
driver.

The old driver can still be used through a Kconfig option, to preserve
backward compatibility with old DTBs.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: r8a7790: Add new CPG/MSSR driver

Add a new R-Car H2 Clock Pulse Generator / Module Standby and Software
Reset driver, using the CPG/MSSR driver core. This will enable support
for module resets, which are not supported by the existing driver.

The old driver can still be used through a Kconfig option, to preserve
backward compatibility with old DTBs.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: Rework Kconfig and Makefile logic

The goals are to:
- Allow precise control over and automatic selection of which
(sub)drivers are used for which SoC (which may change in the
future),
- Allow adding support for new SoCs easily,
- Allow compile-testing of all (sub)drivers,
- Keep driver selection logic in the subsystem-specific Kconfig,
independent from the architecture-specific Kconfig (i.e. no "select"
from arch/arm64/Kconfig.platforms), to avoid dependencies.

This is implemented by:
- Introducing Kconfig symbols for all drivers and sub-drivers,
- Introducing the Kconfig symbol CLK_RENESAS, which is enabled
automatically when building for a Renesas ARM platform, and which
enables all required drivers without interaction of the user, based
on SoC-specific ARCH_* symbols,
- Allowing the user to enable any Kconfig symbol manually if
COMPILE_TEST is enabled,
- Using the new Kconfig symbols instead of the ARCH_* symbols to
control compilation in the Makefile,
- Always entering drivers/clk/renesas/ during the build.

Note that currently not all (sub)drivers are enabled for
compile-testing, as they depend on independent fixes in other
subsystems.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>

clk: renesas: cpg-mssr: Initialize error pointer using ERR_PTR()

Coccinelle warns:

drivers/clk/renesas/renesas-cpg-mssr.c:323:14-21: ERROR: PTR_ERR applied after initialization to constant on line 260

Initialize clk using ERR_PTR(-ENOTSUPP) instead of NULL to fix this.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: Use pm_clk_no_clocks() helper i.s.o. direct access

The pm_subsys_data.clock_list member exists only if CONFIG_PM_CLK=y.
Hence direct accesses to this field break compile-testing on platforms
where CONFIG_PM_CLK=n.

To fix this, use the pm_clk_no_clocks() helper instead, for which a
dummy version is provided if CONFIG_PM_CLK=n.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <simon.horman@netronome.com>

clk: renesas: cpg-mssr: Add support for fixing up clock tables

The same SoC may have different clocks and/or module clock parents,
depending on SoC revision. One option is to use different sets of clock
tables for each SoC revision. However, if the differences are small, it
is much more space-efficient to have a single set of clock tables, and
fix those up at runtime instead.

Hence provide three helpers:
- Two helpers to NULLify core and module clocks that do not exist on
some revisions (NULLified clocks are skipped during the registration
phase),
- One helper to reparent module clocks that have different clock
parents.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Add support for reset control

Add optional support for the Reset Control feature of the Renesas Clock
Pulse Generator / Module Standby and Software Reset module on R-Car
Gen2, R-Car Gen3, and RZ/G1 SoCs.

This allows to reset SoC devices using the Reset Controller API.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>

clk: renesas: cpg-mssr: Rename cpg_mssr_priv.mstp_lock

The spinlock is used to protect Read-Modify-Write register accesses,
which won't be limited to SMSTPCR register accesses.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>

clk: renesas: cpg-mssr: Document suitability for RZ/G1

The Renesas CPG/MSSR driver is already in active use for RZ/G1 since
commits c0b2d75d2a4bf6a3 ("clk: renesas: cpg-mssr: Add R8A7743 support")
and 9127d54bb8947159 ("clk: renesas: cpg-mssr: Add R8A7745 support").

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>

clk: renesas: cpg-mssr: Migrate to CLK_IS_CRITICAL

When the Renesas CPG/MSSR driver was introduced, it was anticipated that
critical clocks would be handled through a new CLK_ENABLE_HAND_OFF flag
soon. However, CLK_ENABLE_HAND_OFF never made it upstream.

Instead, commit 32b9b10961860860 ("clk: Allow clocks to be marked as
CRITICAL") introduced CLK_IS_CRITICAL, a flag with slightly differing
semantics. Still, it can be used to prevent e.g. the GIC module clock
from being turned off, until the GIC-400 driver has full support for
Runtime PM.

Hence migrate the Renesas CPG/MSSR driver from CLK_ENABLE_HAND_OFF to
CLK_IS_CRITICAL.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>

clk: renesas: cpg-mssr: Add R8A7745 support

Add RZ/G1E (R8A7745) Clock Pulse Generator / Module Standby and Software
Reset support, using the CPG/MSSR driver core and the common R-Car Gen2
(and RZ/G) code.

Based on the proof-of-concept R8A7791 CPG/MSSR patch by Geert
Uytterhoeven <geert+renesas@glider.be>.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Add R8A7743 support

Add RZ/G1M (R8A7743) Clock Pulse Generator / Module Standby and Software
Reset support, using the CPG/MSSR driver core and the common R-Car Gen2
(and RZ/G) code.

Based on the proof-of-concept R8A7791 CPG/MSSR patch by Geert
Uytterhoeven <geert+renesas@glider.be>.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Remove bogus commas from error messages

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Fix inverted debug check

The intention was to enable the checks if debugging is enabled, not
disabled.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: renesas: cpg-mssr: Fix inverted debug check

The intention was to enable the checks if debugging is enabled, not
disabled.

Fixes: f793d1e51705b276 ("clk: shmobile: Add new CPG/MSSR driver core")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: cpg-mssr: Always use readl()/writel()

The Renesas CPG/MSSR driver core uses a mix of clk_readl()/clk_writel()
and readl()/writel() to access the clock registers. Settle on the
generic readl()/writel().

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>

clk: renesas: cpg-mssr: Add support for R-Car M3-W

Initial support for R-Car M3-W (r8a7796), including basic core clocks,
and SCIF2 (console) and INTC-AP (GIC) module clocks.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Simon Horman <horms+renesas@verge.net.au>

clk: renesas: cpg-mssr: Use always-on governor for Clock Domain

As a pure Clock Domain does not have the concept of powering the domain
itself, the CPG/MSTP driver does not provide power_off() and power_on()
callbacks.
However, the genpd core may still perform a dummy power down, causing
/sys/kernel/debug/pm_genpd/pm_genpd_summary to report the domain's
status being "off-0".

Use the always-on governor to make sure the domain is never powered
down, and always shows up as "on" in pm_genpd_summary.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>

clk: renesas: cpg-mssr: Postpone call to pm_genpd_init()

All local setup of the generic_pm_domain structure should have been
completed before calling pm_genpd_init().

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>

clk: renesas: cpg-mssr: Export cpg_mssr_{at,de}tach_dev()

The R-Car SYSC PM Domain driver has to power manage devices in power
areas using clocks. To reuse code and to share knowledge of clocks
suitable for power management, this is ideally done through the existing
cpg_mssr_attach_dev() and cpg_mssr_detach_dev() callbacks.

Hence these callbacks can no longer rely on their "domain" parameter
pointing to the CPG/MSSR Clock Domain. To handle this, keep a pointer to
the clock domain in a static variable. cpg_mssr_attach_dev() has to
support probe deferral, as the R-Car SYSC PM Domain may be initialized,
and devices may be added to it, before the CPG/MSSR Clock Domain is
initialized.

Dummy callbacks are provided for the case where CPG/MSTP support is not
included, so the rcar-sysc driver won't have to care about this.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

clk: renesas: cpg-mssr: Drop check for CONFIG_PM_GENERIC_DOMAINS_OF

As of commit 71d076ceb245f0d9 ("ARM: shmobile: Enable PM and
PM_GENERIC_DOMAINS for SoCs with PM Domains"),
CONFIG_PM_GENERIC_DOMAINS_OF is always enabled for SoCs with a CPG/MSSR
block.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

clk: renesas: cpg-mssr: add generic support for read-only DIV6 clocks

Gen3 has two clocks (OSC and R) which look like a DIV6 clock but their
divider value is read-only and depends on MD pins at bootup. Add support
for such clocks by reading the value and adding a fixed clock.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

clk: renesas: move drivers to renesas directory

This is part of an ongoing process to migrate from ARCH_SHMOBILE to
ARCH_RENESAS the motivation for which being that RENESAS seems to be a more
appropriate name than SHMOBILE for the majority of Renesas ARM based SoCs.

Along with the above mentioned Kconfig changes it seems appropriate
to also rename directories that only hold drivers for such SoCs.

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>