clk: imx: composite-8m: Delete two unnecessary initialisations in __imx8m_clk_hw_composite()

Two local variables will eventually be set to appropriate pointers
a bit later. Thus omit the explicit initialisation at the beginning.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Link: https://lore.kernel.org/r/6604590e-d0f7-4798-a1b9-b2f474f3a642@web.de
Signed-off-by: Abel Vesa <abel.vesa@linaro.org>

clk: imx: composite-8m: Less function calls in __imx8m_clk_hw_composite() after error detection

The function “kfree” was called in up to three cases
by the function “__imx8m_clk_hw_composite” during error handling
even if the passed variables contained a null pointer.

Adjust jump targets according to the Linux coding style convention.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Link: https://lore.kernel.org/r/147ca1e6-69f3-4586-b5b3-b69f9574a862@web.de
Signed-off-by: Abel Vesa <abel.vesa@linaro.org>

clk: imx: composite-8m: fix clock pauses when set_rate would be a no-op

Reconfiguring the clock divider to the exact same value is observed
on an i.MX8MN to often cause a longer than usual clock pause, probably
because the divider restarts counting whenever the register is rewritten.

This issue doesn't show up normally, because the clock framework will
take care to not call set_rate when the clock rate is the same.
However, when we reconfigure an upstream clock, the common code will
call set_rate with the newly calculated rate on all children, e.g.:

- sai5 is running normally and divides Audio PLL out by 16.
- Audio PLL rate is increased by 32Hz (glitch-free kdiv change)
- rates for children are recalculated and rates are set recursively
- imx8m_clk_composite_divider_set_rate(sai5) is called with
32/16 = 2Hz more
- imx8m_clk_composite_divider_set_rate computes same divider as before
- divider register is written, so it restarts counting from zero and
MCLK is briefly paused, so instead of e.g. 40ns, MCLK is low for 120ns.

Some external clock consumers can be upset by such unexpected clock pauses,
so let's make sure we only rewrite the divider value when the value to be
written is actually different.

Fixes: d3ff9728134e ("clk: imx: Add imx composite clock")
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Link: https://lore.kernel.org/r/20230807082201.2332746-1-a.fatoum@pengutronix.de
Signed-off-by: Abel Vesa <abel.vesa@linaro.org>

clk: imx: composite-8m: Add imx8m_divider_determine_rate

Currently, certain clocks are derrived as a divider from their
parent clock. For some clocks, even when CLK_SET_RATE_PARENT
is set, the parent clock is not properly set which can lead
to some relatively inaccurate clock values.

Unlike imx/clk-composite-93 and imx/clk-divider-gate, it
cannot rely on calling a standard determine_rate function,
because the 8m composite clocks have a pre-divider and
post-divider. Because of this, a custom determine_rate
function is necessary to determine the maximum clock
division which is equivalent to pre-divider * the
post-divider.

With this added, the system can attempt to adjust the parent rate
when the proper flags are set which can lead to a more precise clock
value.

On the imx8mplus, no clock changes are present.
On the Mini and Nano, this can help achieve more accurate
lcdif clocks. When trying to get a pixel clock of 31.500MHz
on an imx8m Nano, the clocks divided the 594MHz down, but
left the parent rate untouched which caused a calulation error.

Before:
video_pll 594000000
video_pll_bypass 594000000
video_pll_out 594000000
disp_pixel 31263158
disp_pixel_clk 31263158

Variance = -236842 Hz

After this patch:
video_pll 31500000
video_pll_bypass 31500000
video_pll_out 31500000
disp_pixel 31500000
disp_pixel_clk 31500000

Variance = 0 Hz

All other clocks rates and parent were the same.
Similar results on imx8mm were found.

Fixes: 690dccc4a0bf ("Revert "clk: imx: composite-8m: Add support to determine_rate"")
Signed-off-by: Adam Ford <aford173@gmail.com>
Reviewed-by: Abel Vesa <abel.vesa@linaro.org>
Tested-by: Fabio Estevam <festevam@gmail.com>
Link: https://lore.kernel.org/r/20230506195325.876871-1-aford173@gmail.com
Signed-off-by: Abel Vesa <abel.vesa@linaro.org>

Revert "clk: imx: composite-8m: Add support to determine_rate"

This reverts commit 156e96ff2172518b6f83e97d8f11f677bc668e22.

This patch was found to cause some division issues on the i.MX8MP
which causes the video clocks to not properly divide when division
was greate than 8. This causes video failures on disp1_pix and
disp2_pix clocks.

Until a better solution is found, we'll have to revert this.

Signed-off-by: Adam Ford <aford173@gmail.com>
Link: https://lore.kernel.org/r/20230423123828.1346511-1-aford173@gmail.com
Acked-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: imx: composite-8m: Add support to determine_rate

Similar to imx/clk-composite-93 and imx/clk-divider-gate, the
imx8m_clk_composite_divider_ops can support determine_rate.
Without this the parent clocks are set to a fixed value, and
if a consumer needs a slower reate, the clock is divided, but
the division is only as good as the parent clock rate.

With this added, the system can attempt to adjust the parent rate
if the proper flags are set which can lead to a more precise clock
value.

Signed-off-by: Adam Ford <aford173@gmail.com>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Abel Vesa <abel.vesa@linaro.org>
Link: https://lore.kernel.org/r/20230323230127.120883-2-aford173@gmail.com

clk: imx8m: check mcore_booted before register clk

If mcore_booted is true, ignore the clk root gate registration and
this will simplify AMP clock management and avoid system hang unexpectly
especially Linux shutdown clk used by mcore.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Abel Vesa <abel.vesa@nxp.com>
Link: https://lore.kernel.org/r/20220228124112.3974242-2-peng.fan@oss.nxp.com
[abelvesa@kernel.org: Removed if-case for when mcore_booted is true]
Signed-off-by: Abel Vesa <abel.vesa@nxp.com>

clk: imx: Rework all imx_clk_hw_composite wrappers

Rather than having multiple different macros for each different type
of imx8m_clk_hw_composite, implement them in such a way so we can
take advantage the most of the already defined simpler types. Basically,
we end up having one low-level __imx8m_clk_hw_composite function, a
wrapper to simplify the parents related arguments called
_imx8m_clk_hw_composite and then all the types can use those for each
specific case.

Signed-off-by: Abel Vesa <abel.vesa@nxp.com>
Link: https://lore.kernel.org/r/1631521490-17171-8-git-send-email-abel.vesa@nxp.com
Reviewed-by: Stephen Boyd <sboyd@kernel.org>

clk: imx8m: fix clock tree update of TF-A managed clocks

On the i.MX8M*, the TF-A exposes a SiP (Silicon Provider) service
for DDR frequency scaling. The imx8m-ddrc-devfreq driver calls the
SiP and then does clk_set_parent on the DDR muxes to synchronize
the clock tree.

Since 936c383673b9 ("clk: imx: fix composite peripheral flags"),
these TF-A managed muxes have SET_PARENT_GATE set, which results
in imx8m-ddrc-devfreq's clk_set_parent after SiP failing with -EBUSY:

echo 25000000 > userspace/set_freq
imx8m-ddrc-devfreq 3d400000.memory-controller: failed to set
dram_apb parent: -16

Fix this by adding a new i.MX composite flag for firmware managed
clocks, which clears SET_PARENT_GATE.

This is safe to do, because updating the Linux clock tree to reflect
reality will always be glitch-free.

Fixes: 936c383673b9 ("clk: imx: fix composite peripheral flags")
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Reviewed-by: Abel Vesa <abel.vesa@nxp.com>
Link: https://lore.kernel.org/r/20210810151432.9228-1-a.fatoum@pengutronix.de
Signed-off-by: Abel Vesa <abel.vesa@nxp.com>

clk: imx: fix composite peripheral flags

According to RM, for peripheral clock slice,
"IP clock slices must be stopped to change the clock source.".

So we must have CLK_SET_PARENT_GATE flag to avoid glitch.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

clk: imx: Support building i.MX common clock driver as module

There are more and more requirements of building SoC specific drivers
as modules, add support for building i.MX common clock driver as module
to meet the requirement.

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

clk: imx: add imx8m_clk_hw_composite_bus

Introduce imx8m_clk_hw_composite_bus api for bus clk root slice usage.
Because the mux switch sequence issue, we could not reuse Peripheral
Clock Slice code, need use composite specific mux operation.

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

clk: imx: add mux ops for i.MX8M composite clk

The CORE/BUS root slice has following design, simplied graph:
The difference is core not have pre_div block.
A composite core/bus clk has 8 inputs for mux to select, saying clk[0-7].

It support target(smart) interface and normal interface. Target interface
is exported for programmer easy to configure ccm root. Normal interface
is also exported, but we not use it in our driver, because it will
introduce more complexity compared with target interface.

The normal interface simplified as below:
SEL_A GA
+--+ +-+
| +->+ +------+
CLK[0-7]--->+ | +-+ |
| | | +----v---+ +----+
| +--+ |pre_diva+----> | +---------+
| +--------+ |mux +--+post_div |
| +--+ |pre_divb+--->+ | +---------+
| | | +----^---+ +----+
+--->+ | +-+ |
| +->+ +------+
+--+ +-+
SEL_B GB

The mux in the upper pic is not the target interface MUX, target
interface MUX is hiding SEL_A and SEL_B. When you choose clk[0-7],
you are actually writing SEL_A or SEL_B depends on the internal
counter which will also control the internal "mux".

The target interface simplified as below which is used by Linux Kernel:
CLK[0-7]--->MUX-->Gate-->pre_div-->post_div

A requirement of the Target Interface's software is that the
target clock source is active, it means when setting SEL_A, the
current input clk to SEL_A must be active, same to SEL_B.

We touch target interface, but hardware logic actually also need
configure normal interface.

There will be system hang, when doing the following steps:
The initial state:
SEL_A/SEL_B are both sourcing from clk0, the internal counter
choose SEL_A.
1. switch mux from clk0 to clk1
The hardware logic will choose SEL_B and configure SEL_B to clk1.
SEL_A no changed.
2. gate off clk0
Disable clk0, then the input to SEL_A is off.
3. swtich from clk1 to clk2
The hardware logic will choose SEL_A and configure SEL_A to clk2,
however the current SEL_A input clk0 is off, the system hang.

The solution to fix the issue is in step 1, write twice to
target interface MUX, it will make SEL_A/SEL_B both sources
from clk1, then no need to care about the state of clk0. And
finally system performs well.

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

clk: imx: drop redundant initialization

No need to initialize flags as 0, remove the initialization.

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

clk: imx: composite-8m: add imx8m_clk_hw_composite_core

There are several clock slices, current composite code
only support bus/ip clock slices, it could not support core
slice.

So introduce a new API imx8m_clk_hw_composite_core to support
core slice. To core slice, post divider with 3 bits width and
no pre divider. Other fields are same as bus/ip slices.

Add a flag IMX_COMPOSITE_CORE for the usecase.

Reviewed-by: Abel Vesa <abel.vesa@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Leonard Crestez <leonard.crestez@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

clk: imx: clk-composite-8m: Switch to clk_hw based API

Switch the imx8m_clk_hw_composite_flags 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.

Reviewed-by: Abel Vesa <abel.vesa@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

clk: imx: clk-composite-8m: add lock to gate/mux

There is a lock to divider in the composite driver, but that's not
enough. lock to gate/mux are also needed to provide exclusive access
to the register.

Fixes: d3ff9728134e ("clk: imx: Add imx composite clock")
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

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: imx: Make parent_names const pointer in composite-8m

The parent_names needs to be pointer to const pointer to const char.

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

clk: imx: remove redundant initialization of ret to zero

The initialization of ret is redundant as it is being re-assigned to
the return value from the call to imx8m_clk_composite_compute_dividers.
Clean this up by removing the initialization.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: imx: Add imx composite clock

Since a lot of clocks on imx8m are formed by a mux, gate, predivider and
divider, the idea here is to combine all of those into one composite clock,
but we need to deal with both predivider and divider at the same time and
therefore we add the imx8m_clk_composite_divider_ops and register
the composite clock with those.

Signed-off-by: Abel Vesa <abel.vesa@nxp.com>
Suggested-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>