mtd: 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 was 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.

Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20230714174751.4060439-1-robh@kernel.org

mtd: nand: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Acked-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com> # atmel
Reviewed-by: Paul Cercueil <paul@crapouillou.net> # ingenic
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> # ingenic
Acked-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> # intel
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> # meson
Acked-by: Roger Quadros <rogerq@kernel.org> # omap_elm
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> # renesas
Reviewed-by: Heiko Stuebner <heiko@sntech.de> # rockchip
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com> # sunxi
Acked-by: Thierry Reding <treding@nvidia.com> # tegra
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20230411113816.3472237-1-u.kleine-koenig@pengutronix.de

mtd: rawnand: denali: Make use of the helper function devm_platform_ioremap_resource_byname()

Use the devm_platform_ioremap_resource_byname() helper instead of
calling platform_get_resource_byname() and devm_ioremap_resource()
separately

Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20210901074116.8983-1-caihuoqing@baidu.com

mtd: rawnand: denali_dt: add reset controlling

According to the Denali NAND Flash Memory Controller User's Guide,
this IP has two reset signals.

rst_n: reset most of FFs in the controller core
reg_rst_n: reset all FFs in the register interface, and in the
initialization sequencer

This commit supports controlling those reset signals.

It is possible to control them separately from the IP point of view
although they might be often tied up together in actual SoC integration.

The IP spec says, asserting only the reg_rst_n without asserting rst_n
will cause unpredictable behavior in the controller. So, the driver
deasserts ->rst_reg and ->rst in this order.

Another thing that should be kept in mind is the automated initialization
sequence (a.k.a. 'bootstrap' process) is kicked off when reg_rst_n is
deasserted.

When the reset is deasserted, the controller issues a RESET command
to the chip select 0, and attempts to read out the chip ID, and further
more, ONFI parameters if it is an ONFI-compliant device. Then, the
controller sets up the relevant registers based on the detected
device parameters.

This process might be useful for tiny boot firmware, but is redundant
for Linux Kernel because nand_scan_ident() probes devices and sets up
parameters accordingly. Rather, this hardware feature is annoying
because it ends up with misdetection due to bugs.

So, commit 0615e7ad5d52 ("mtd: nand: denali: remove Toshiba and Hynix
specific fixup code") changed the driver to not rely on it.

However, there is no way to prevent it from running. The IP provides
the 'bootstrap_inhibit_init' port to suppress this sequence, but it is
usually out of software control, and dependent on SoC implementation.
As for the Socionext UniPhier platform, LD4 always enables it. For the
later SoCs, the bootstrap sequence runs depending on the boot mode.

I added usleep_range() to make the driver wait until the sequence
finishes. Otherwise, the driver would fail to detect the chip due
to the race between the driver and hardware-controlled sequence.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

mtd: rawnand: denali_dt: Add support for configuring SPARE_AREA_SKIP_BYTES

The SPARE_AREA_SKIP_BYTES register is reset when the controller reset
signal is toggled. Yet, this register must be configured to match the
content of the NAND OOB area. The current default value is always set
to 8 and is programmed into the hardware in case the hardware was not
programmed before (e.g. in a bootloader) with a different value. This
however does not work when the block is reset properly by Linux.

On Altera SoCFPGA CycloneV, ArriaV and Arria10, which are the SoCFPGA
platforms which support booting from NAND, the SPARE_AREA_SKIP_BYTES
value must be set to 2. On Socionext Uniphier, the value is 8. This
patch adds support for preconfiguring the default value and handles
the special SoCFPGA case by setting the default to 2 on all SoCFPGA
platforms, while retaining the original behavior and default value of
8 on all the other platforms.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Vignesh Raghavendra <vigneshr@ti.com>
To: linux-mtd@lists.infradead.org
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

mtd: rawnand: denali_dt: error out if platform has no associated data

denali->ecc_caps is a mandatory parameter. If it were left unset,
nand_ecc_choose_conf() would end up with NULL pointer access.

So, every compatible must be associated with proper denali_dt_data.
If of_device_get_match_data() returns NULL, let it fail immediately.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

mtd: rawnand: denali: remove the old unified controller/chip DT support

Commit d8e8fd0ebf8b ("mtd: rawnand: denali: decouple controller and
NAND chips") supported the new binding for the separate controller/chip
representation, keeping the backward compatibility.

All the device trees in upstream migrated to the new binding.

Remove the support for the old binding.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

mtd: Remove dev_err() usage after platform_get_irq()

We don't need dev_err() messages when platform_get_irq() fails now that
platform_get_irq() prints an error message itself when something goes
wrong. Let's remove these prints with a simple semantic patch.

// <smpl>
@@
expression ret;
struct platform_device *E;
@@

ret =
(
platform_get_irq(E, ...)
|
platform_get_irq_byname(E, ...)
);

if ( \( ret < 0 \| ret <= 0 \) )
{
(
-if (ret != -EPROBE_DEFER)
-{ ...
-dev_err(...);
-... }
|
...
-dev_err(...);
)
...
}
// </smpl>

While we're here, remove braces on if statements that only have one
statement (manually).

Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: Marek Vasut <marek.vasut@gmail.com>
Cc: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Vignesh Raghavendra <vigneshr@ti.com>
Cc: linux-mtd@lists.infradead.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

mtd: rawnand: denali: decouple controller and NAND chips

Currently, this driver sticks to the legacy NAND model because it was
upstreamed before commit 2d472aba15ff ("mtd: nand: document the NAND
controller/NAND chip DT representation"). However, relying on the
dummy_controller is already deprecated.

Switch over to the new controller/chip representation.

The struct denali_nand_info has been split into denali_controller
and denali_chip, to contain the controller data, per-chip data,
respectively.

One problem is, this commit changes the DT binding. So, as always,
the backward compatibility must be taken into consideration.

In the new binding, the controller node expects

#address-cells = <1>;
#size-cells = <0>;

... since the child nodes represent NAND chips.

In the old binding, the controller node may have subnodes, but they
are MTD partitions.

The denali_dt_is_legacy_binding() exploits it to distinguish old/new
platforms.

Going forward, the old binding is only allowed for existing DT files.
I updated the binding document.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

mtd: rawnand: denali_dt: remove single anonymous clock support

Commit 6f1fe97bec34 ("mtd: rawnand: denali_dt: add more clocks based
on IP datasheet") introduced a more correct binding that requires
three named clocks.

Now that all upstream DT files migrated over to it, remove the single
anonymous clock support.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Dinh Nguyen <dinguyen@kernel.org>
Acked-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

mtd: rawnand: denali: use SPDX-License-Identifier and fix license mismatch

Use SPDX-License-Identifier instead of the license boilerplates.

This conversion makes it easier for us to scan the license, then
I notice license mismatch problems.

The license blocks in denali* indicate GPL-2.0 "only", while the
MODULE_LICENSE in denali.c and denali_dt.c is GPL-2.0 "or later"
as explained in include/linux/module.h as follows:

"GPL" [GNU Public License v2 or later]
"GPL v2" [GNU Public License v2]

I fixed the MODULE_LICENSE tags, assuming the license blocks are
the authors' intention.

Also, add missing MODULE_DESCRIPTION/AUTHOR to denali.c

While I am touching the license things, I added my credit to denali.c
because this driver was largely re-written by me in 2017.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

mtd: rawnand: denali: optimize timing parameters for data interface

This commit improves the ->setup_data_interface() hook.

The denali_setup_data_interface() needs the frequency of clk_x
and the ratio of clk_x / clk.

The latter is currently hardcoded in the driver, like this:

#define DENALI_CLK_X_MULT 6

The IP datasheet requires that clk_x / clk be 4, 5, or 6. I just
chose 6 because it is the most defensive value, but it is not optimal.
By getting the clock rate of both "clk" and "clk_x", the driver can
compute the timing values more precisely.

To not break the existing platforms, the fallback value, 50 MHz is
provided. It is true for all upstreamed platforms.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
Tested-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

mtd: rawnand: denali_dt: add more clocks based on IP datasheet

Currently, denali_dt.c requires a single anonymous clock, but
the Denali User's Guide requires three clocks for this IP:

- clk: controller core clock

- clk_x: bus interface clock

- ecc_clk: clock at which ECC circuitry is run

This commit supports these named clocks to represent the real hardware.

For the backward compatibility, the driver still accepts a single clock
just as before. The clk_x_rate is taken from the clock driver again if
the named clock "clk_x" is available. This will happen only for future
DT, hence the existing DT files are not affected.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
Tested-by: Richard Weinberger <richard@nod.at>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

mtd: rawnand: denali_dt: use dev as a shorthand of &pdev->dev

The probe function references &pdev->dev many times, and I will add
more soon. Add 'dev' as a shorthand.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
Tested-by: Richard Weinberger <richard@nod.at>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

mtd: rawnand: denali_dt: set clk_x_rate to 200 MHz unconditionally

Since commit 1bb88666775e ("mtd: nand: denali: handle timing parameters
by setup_data_interface()"), denali_dt.c gets the clock rate from the
clock driver. The driver expects the frequency of the bus interface
clock, whereas the clock driver of SOCFPGA provides the core clock.
Thus, the setup_data_interface() hook calculates timing parameters
based on a wrong frequency.

To make it work without relying on the clock driver, hard-code the clock
frequency, 200MHz. This is fine for existing DT of UniPhier, and also
fixes the issue of SOCFPGA because both platforms use 200 MHz for the
bus interface clock.

Fixes: 1bb88666775e ("mtd: nand: denali: handle timing parameters by setup_data_interface()")
Cc: linux-stable <stable@vger.kernel.org> #4.14+
Reported-by: Philipp Rosenberger <p.rosenberger@linutronix.de>
Suggested-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>

mtd: nand: move raw NAND related code to the raw/ subdir

As part of the process of sharing more code between different NAND
based devices, we need to move all raw NAND related code to the raw/
subdirectory.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>