clk: imx: fix compile testing imxrt1050

Randconfig testing revealed multiple issues with this driver:

ERROR: modpost: missing MODULE_LICENSE() in drivers/clk/imx/clk-imxrt1050.o
ERROR: modpost: "imx_clk_hw_pllv3" [drivers/clk/imx/clk-imxrt1050.ko] undefined!
ERROR: modpost: "imx_clk_hw_pfd" [drivers/clk/imx/clk-imxrt1050.ko] undefined!

Export the necessary symbols from the core clk driver and add the
license and author tags. To find this type of problem more easily
in the future, also enable building on other platforms, as we do for
the other i.MX clk drivers.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20221215165836.2136448-1-arnd@kernel.org
Acked-by: Jesse Taube <Mr.Bossman075@gmail.com>
Reviewed-by: Abel Vesa <abel.vesa@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: imx: Use div64_ul instead of do_div

do_div() does a 64-by-32 division. Here the divisor is an unsigned long
which on some platforms is 64 bit wide. So use div64_ul instead of do_div
to avoid a possible truncation.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Changcheng Deng <deng.changcheng@zte.com.cn>
Reviewed-by: Abel Vesa <abel.vesa@nxp.com>
Link: https://lore.kernel.org/r/20211118080634.165275-1-deng.changcheng@zte.com.cn
Signed-off-by: Abel Vesa <abel.vesa@nxp.com>

clk: imx: Fix and update kerneldoc

Fix and add missing kerneldoc to fix compile warnings like:

drivers/clk/imx/clk-pfd.c:27: warning: Function parameter or member 'hw' not described in 'clk_pfd'
drivers/clk/imx/clk-pllv3.c:53: warning: Function parameter or member 'ref_clock' not described in 'clk_pllv3'

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

clk: imx: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1].

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20200727200922.GA2326@embeddedor
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: imx: clk-pllv3: Use readl_relaxed_poll_timeout() for PLL lock wait

Use readl_relaxed_poll_timeout() for PLL lock wait which can simplify the
code a lot.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Reviewed-by: Abel Vesa <abel.vesa@nxp.com>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

clk: imx: clk-pllv3: Switch to clk_hw based API

Switch the imx_clk_hw_pllv3 function to clk_hw based API, rename
accordingly and add a macro for clk based legacy. This allows us
to move closer to a clear split between consumer and provider clk
APIs.

Signed-off-by: Abel Vesa <abel.vesa@nxp.com>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 159

Based on 1 normalized pattern(s):

the code contained herein is licensed under the gnu general public
license you may obtain a copy of the gnu general public license
version 2 or later at the following locations http www opensource
org licenses gpl license html http www gnu org copyleft gpl html

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 161 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.383790741@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

clk: imx: clk-pllv3: mark expected switch fall-throughs

In preparation to enabling -Wimplicit-fallthrough, mark switch
cases where we are expecting to fall through.

This patch fixes the following warnings:

drivers/clk/imx/clk-pllv3.c: In function ‘imx_clk_pllv3’:
drivers/clk/imx/clk-pllv3.c:446:18: warning: this statement may fall through [-Wimplicit-fallthrough=]
pll->div_shift = 1;
~~~~~~~~~~~~~~~^~~
drivers/clk/imx/clk-pllv3.c:447:2: note: here
case IMX_PLLV3_USB:
^~~~
drivers/clk/imx/clk-pllv3.c:453:21: warning: this statement may fall through [-Wimplicit-fallthrough=]
pll->denom_offset = PLL_IMX7_DENOM_OFFSET;
^
drivers/clk/imx/clk-pllv3.c:454:2: note: here
case IMX_PLLV3_AV:
^~~~

Warning level 3 was used: -Wimplicit-fallthrough=3

This patch is part of the ongoing efforts to enable
-Wimplicit-fallthrough.

Fixes: b4a4cb5a0454 ("clk: imx: correct i.MX7D AV PLL num/denom offset")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: imx: correct i.MX7D AV PLL num/denom offset

According reference manual, i.MX7D's audio/video PLL's
num/denom register offset are 0x20/0x30, they are different
from i.MX6's audio/video PLL, correct it by introducing new
offset variables for audio/video PLL and using runtime
assignment based on PLL type.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: imx7d: Fix the DDR PLL enable bit

Commit ad14972422899b6 ("clk: imx7d: Fix the powerdown bit location
of PLL DDR") used the incorrect bit for the IMX_PLLV3_DDR_IMX7 case.

Fix it accordingly to avoid a kernel hang.

Reported-by: Leonard Crestez <leonard.crestez@nxp.com>
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Reviewed-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: imx7d: Fix the powerdown bit location of PLL DDR

According to the MX7D Reference Manual the powerdown bit of
CCM_ANALOG_PLL_DDRn register is bit 20, so fix it accordingly.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Reviewed-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: imx: pllv3: support fractional multiplier on vf610 PLL1/PLL2

On vf610, PLL1 and PLL2 have registers to configure fractional part of
frequency multiplier.

This patch adds support for these registers.

This fixes "fast system clock" issue on boards where bootloader sets
fractional multiplier for PLL1.

Suggested-by: Andrey Smirnov <andrew.smirnov@gmail.com>
CC: Chris Healy <cphealy@gmail.com>
Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
Tested-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: imx: improve precision of AV PLL to 1 Hz

The audio and video PLLs are designed to have a precision of 1 Hz if some
conditions are met. The current implementation only allows a precision that
depends on the rate of the parent clock. E.g., if the parent clock is 24
MHz, the precision will be 24 Hz; or more generally the precision will be

p / 10^6 Hz

where p is the parent clock rate. This comes down to how the register
values for the PLL's fractional loop divider are chosen.

The clock rate calculation for the PLL is

PLL output frequency = Fref * (DIV_SELECT + NUM / DENOM)

or with a shorter notation

r = p * (d + a / b)

In addition to all variables being integers, we also have the following
conditions:

27 <= d <= 54

-2^29 <= a <= 2^29-1
0 < b <= 2^30-1
|a| < b

Here, d, a and b are register values for the fractional loop divider. We
want to chose d, a and b such that f(p, r) = p, i.e. f is our round_rate
function. Currently, d and b are chosen as

d = r / p
b = 10^6

hence we get the poor precision. And a is defined in terms of r, d, p and
b:

a = (r - d * p) * b / p

I propose that if p <= 2^30-1 (i.e., the max value for b), we chose b as

b = p

We can do this since

|a| < b

|(r - d * p) * b / p| < b

|r - d * p| < p

Which have two solutions, one of them is when p < 0, so we can skip that
one. The other is when p > 0 and

p * (d - 1) < r < p * (d + 1)

Substitute d = r / p:

(r - p) < r < (r + p) <=> p > 0

So, as long as p > 0, we can chose b = p. This is a good choise for b since

a = (r - d * p) * b / p
= (r - d * p) * p / p
= r - d * p

r = p * (d + a / b)
= p * d + p * a / b
= p * d + p * a / p
= p * d + a

and if d = r / p:

a = r - d * p
= r - r / p * p
= 0

r = p * d + a
= p * d + 0
= p * r / p
= r

I reckon this is the intention by the design of the clock rate formula.

Signed-off-by: Emil Lundmark <emil@limesaudio.com>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
Acked-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: imx: fix integer overflow in AV PLL round rate

Since 'parent_rate * mfn' may overflow 32 bits, the result should be
stored using 64 bits.

The problem was discovered when trying to set the rate of the audio PLL
(pll4_post_div) on an i.MX6Q. The desired rate was 196.608 MHz, but
the actual rate returned was 192.000570 MHz. The round rate function should
have been able to return 196.608 MHz, i.e., the desired rate.

Fixes: ba7f4f557eb6 ("clk: imx: correct AV PLL rate formula")
Cc: Anson Huang <b20788@freescale.com>
Signed-off-by: Emil Lundmark <emil@limesaudio.com>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
Acked-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: imx: refine the powerdown bit of clk-pllv3

The powerdown bit is a bit confused, let's change it to power_bit
to relfect both powerdown and powerup case according to different
plls.

Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

clk: imx: clk-pllv3: fix incorrect handle of enet powerdown bit

After commit f53947456f98 ("ARM: clk: imx: update pllv3 to support imx7"),
the former used BM_PLL_POWER bit is not correct anymore for IMX7 ENET.
Instead, pll->powerdown holds the correct bit, so using powerdown bit
in clk_pllv3_{prepare | unprepare} functions.

Fixes: f53947456f98 ("ARM: clk: imx: update pllv3 to support imx7")
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

clk: imx: correct AV PLL rate formula

The audio/video PLL's rate calculation is as below in RM:

Fref * (DIV_SELECT + NUM / DENOM), in origin clk-pllv3's
code, below code is used:

(parent_rate * div) + ((parent_rate / mfd) * mfn

as it does NOT consider the float data using div, so below
formula should be used as a decent method:

(parent_rate * div) + ((parent_rate * mfn) / mfd)

and we also need to consider parent_rate * mfd may overflow
a 32 bit value, 64 bit value should be used.

After updating this formula, the dram PLL's rate is
1066MHz, which is correct, while the old formula gets
1056MHz.

[Aisheng: fix clk_pllv3_av_round_rate too]

Signed-off-by: Anson Huang <b20788@freescale.com>
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

clk: imx: return correct frequency for Ethernet PLL

The i.MX 7 designs Ethernet PLL provides a 1000MHz reference clock.
Store the reference clock in the clk_pllv3 structure according to
the PLL type.

Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

clk: imx: add 'is_prepared' clk_ops callback for pllv3 clk

Add 'is_prepared' callback function for pllv3 type clk to make sure when
the system is bootup, the unused clk is in a known state to match the
prepare count info.

Signed-off-by: Bai Ping <b51503@freescale.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

clk: i.MX: Remove clk.h include

Clock provider drivers generally shouldn't include clk.h because
it's the consumer API. Remove the include here because this is a
provider driver.

Cc: Alexander Shiyan <shc_work@mail.ru>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

ARM: clk: imx: update pllv3 to support imx7

Add type IMX_PLLV3_ENET_IMX7

Signed-off-by: Frank Li <Frank.Li@freescale.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

ARM: imx: using unsigned variable for do_div

The definition of do_div uses unsigned long long
variable as its first parameter, better to pass
a u64 variable as first parameter when calling
do_div function.

Signed-off-by: Anson Huang <b20788@freescale.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

ARM: imx: move clock drivers into drivers/clk

After the cleanup on clock drivers, they are now ready to be moved into
drivers/clk. Let's move them into drivers/clk/imx folder.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>