The MP style clocks support an mux with pre-dividers. While the driver
correctly accounted for them in the .determine_rate callback, it did
not in the .recalc_rate and .set_rate callbacks.
This means when calculating the factors in the .set_rate callback, they
would be off by a factor of the active pre-divider. Same goes for
reading back the clock rate after it is set.
Cc: stable@vger.kernel.org
Fixes: 2ab836db50 ("clk: sunxi-ng: Add M-P factor clock support")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
PTR_ERR should access the value just tested by IS_ERR, otherwise
the wrong error code will be returned.
Fixes: 783ab76ae5 ("clk: sunxi-ng: Add A80 Display Engine CCU")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
We get a link error when CCU_MULT is not set with the
newly added driver:
drivers/clk/sunxi-ng/ccu-sun5i.o:(.data.__compound_literal.17+0x4): undefined reference to `ccu_mult_ops'
drivers/clk/sunxi-ng/ccu-sun5i.o:(.data.__compound_literal.5+0x4): undefined reference to `ccu_mult_ops'
Fixes: 5e73761786 ("clk: sunxi-ng: Add sun5i CCU driver")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
This kzalloc() could fail. Let's bail out with -ENOMEM here
instead of NULL dereferencing. That silences static checkers. We
should also cleanup on the error path even though this function
returning an error probably means the system won't boot.
Cc: Chen-Yu Tsai <wens@csie.org>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
With the A80 SoC, Allwinner grouped and moved some subsystem specific
clock controls to a separate address space, and possibly separate
hardware block.
One such subsystem is the display engine. The main clock control unit
now only has 1 set of bus gate, dram gate, module clock, and reset
control for the entire display subsystem. These feed into a secondary
clock control unit, which has controls for each individual module
of the display pipeline. This block is not documented in the user
manual. Allwinner's kernel was used as the reference.
Add support for the display engine clock controls found on the A80.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Add support for the USB clock controls found on the A80.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Add support for the main clock unit found in the A80. Some clocks were
not documented in the released user manual, but were found in the
official kernel from Allwinner. These include controls for the I2S,
SPDIF, SATA, and eDP blocks.
Note that on the A80, some subsystems have separate clock controllers
downstream of the main clock unit. These include the MMC, USB, and
display engine subsystems.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
On the Allwinner A80 SoC, the PLL lock status indicators are grouped
together in a separate register, as opposed to being scattered in each
PLL's configuration register.
Add a flag to support this.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
If the CLK_SET_RATE_PARENT flag is set, we want to try getting the
closest parent rate.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
This patch adds support for the CLK_SET_RATE_NO_REPARENT flag to the
mux determine_rate helper, based on examples from clk-composite and
clk-mux.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
The determine_rate helper used ccu_mux_helper_adjust_parent_for_prediv()
to adjust the parent_rate to account for pre-dividers, but then passed
the pristine parent clock rate from clk_hw_get_rate() to the round()
callback, thereby ignoring the pre-divider adjustment. In addition,
it was saving the adjusted parent rate back into struct
clk_rate_request.
This patch fixes this by saving the pristine parent clock rate, and
adding a copy that is adjusted and passed to the round() callback.
The pristine copy, if it is the best solution, would be saved back
to struct clk_rate_request.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
In order to achieve all the rates asked by the GPU, we might need to change
the parent frequency.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Chen-Yu Tsai <wens@csie.org>
The divider_get_val function that is used in our determine_rate callback
doesn't try to change the parent rate at all, while clk_divider_bestdiv,
used in divider_round_rate, does.
If we have a single parent, call divider_round_rate.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Chen-Yu Tsai <wens@csie.org>
The Allwinner A10s, A13, R8 and NextThing GR8 are all based on the same
silicon, and all share the same clocks.
However, they're not packaged in the same way, and therefore not all the
controllers are actually available on all these SoCs.
Introduce a clock controller driver for all these SoCs with different
compatibles to take that into account.
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Some clocks have a global pre-divider that applies to all their parents.
Since it might also apply to clocks that have a single parent, this is
merged in the ccu_common structure, unlike the other pre-divider settings
that are tied to a specific index, and thus a specific parent.
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Some multipliers have a maximum rate that is lower than what the register
width allows to. Add a field in the multiplier structure to allow CCU
driver to set that maximum.
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
The previous code was always taking 1 as the minimum in it's round_rate
function, ignoring entirely what was set as minimum in the clock
definition.
Make sure that's not the case anymore.
Fixes: 2beaa601c8 ("clk: sunxi-ng: Implement minimum for multipliers")
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
The factors we've seen so far all had an offset of one. However, on the
earlier Allwinner SoCs, some factors could have no offset at all, meaning
that the value computed to reach the rate we want to use was the one we had
to program in the registers.
Implement an additional field for the factors that can have such an offset
(linears, not based on a power of two) to specify that offset.
This offset is not linked to the extremums that can be specified in those
structures too. The minimum and maximum are representing the range of
values we can use to try to compute the best rate. The offset comes later
on when we want to set the best value in the registers.
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Some clocks on the earlier SoCs such as the video PLLs are multipliers with
fractional settings.
Support those cases.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
V3s has a similar but cut-down CCU to H3. Some muxes, especially clocks
about CSI, are different, which makes it to need a new CCU driver.
Add such a new driver for it.
Signed-off-by: Icenowy Zheng <icenowy@aosc.xyz>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
The audio DAI needs to set the clock rates of the ac-dig clock.
To make it possible, the parent PLL audio clock rates should
also be changed. This is possible via "CLK_SET_RATE_PARENT" flag.
Signed-off-by: Mylène Josserand <mylene.josserand@free-electrons.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
As the SPDIF was rarely documented on the earlier Allwinner SoCs
it was assumed that it had a similar clock register to the one
described in the H3 User Manual.
However this is not the case and it looks to shares the same setup
as the I2S clock registers.
Signed-off-by: Marcus Cooper <codekipper@gmail.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
The CPUX clock on A33, which is for the Cortex-A7 cores, is designed to
be changeable by changing the rate of PLL_CPUX.
Add CLK_SET_RATE_PARENT flag to this clock.
Signed-off-by: Icenowy Zheng <icenowy@aosc.xyz>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
When adjusting PLL_CPUX on A33, the PLL is temporarily driven too high,
and the system hangs.
Add a notifier to avoid this situation by temporarily switching to a
known stable 24 MHz oscillator.
Signed-off-by: Icenowy Zheng <icenowy@aosc.xyz>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
When adjusting PLL_CPUX on H3, the PLL is temporarily driven
too high, and the system becomes unstable (oopses or hangs).
Add a notifier to avoid this situation by temporarily switching
to a known stable 24 MHz oscillator.
Signed-off-by: Ondrej Jirman <megous@megous.com>
Tested-by: Lutz Sammer <johns98@gmx.net>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
In the user manual of A33 SoC, the bit 22 and 23 of pll-mipi control
register is called "LDO{1,2}_EN", and according to the BSP source code
from Allwinner [1], the LDOs are enabled during the clock's enabling
process.
The clock failed to generate output if the two LDOs are not enabled.
Add the two bits to the clock's gate bits, so that the LDOs are enabled
when the PLL is enabled.
[1] https://github.com/allwinner-zh/linux-3.4-sunxi/blob/master/drivers/clk/sunxi/clk-sun8iw5.c#L429
Fixes: d05c748bd7 ("clk: sunxi-ng: Add A33 CCU support")
Signed-off-by: Icenowy Zheng <icenowy@aosc.xyz>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
The PLL-MIPI clock is somewhat special as it has its own LDOs which
need to be turned on for this PLL to actually work and output a clock
signal.
Add the 2 LDO enable bits to the gate bits. This fixes issues with
the TCON not sending vblank interrupts when the tcon and dot clock are
indirectly clocked from the PLL-MIPI clock.
Fixes: c6e6c96d8f ("clk: sunxi-ng: Add A31/A31s clocks")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Some checkpatch warnings about spaces were missed and we didn't
mark two structs as static. Clean it up.
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
The usual patches from us, but most notably the introduction of the A64
clocks unit.
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Merge tag 'sunxi-clk-for-4.10' of https://git.kernel.org/pub/scm/linux/kernel/git/mripard/linux into clk-next
Pull Allwinner clock changes from Maxime Ripard:
The usual patches from us, but most notably the introduction of the A64
clocks unit.
* tag 'sunxi-clk-for-4.10' of https://git.kernel.org/pub/scm/linux/kernel/git/mripard/linux:
clk: sunxi-ng: sun8i-h3: Set CLK_SET_RATE_PARENT for audio module clocks
clk: sunxi-ng: sun8i-a23: Set CLK_SET_RATE_PARENT for audio module clocks
clk: sunxi-ng: Add A64 clocks
clk: sunxi-ng: Implement minimum for multipliers
clk: sunxi-ng: Add minimums for all the relevant structures and clocks
clk: sunxi-ng: Finish to convert to structures for arguments
clk: sunxi-ng: Remove the use of rational computations
clk: sunxi-ng: Rename the internal structures
clk: sunxi: mod0: improve function-level documentation
The audio module clocks are supposed to be set according to the sample
rate of the audio stream. The audio PLL provides the clock signal for
these module clocks, and only it is freely tunable.
Set CLK_SET_RATE_PARENT for the audio module clocks so their users can
properly tune the clock rate.
Fixes: 0577e4853b ("clk: sunxi-ng: Add H3 clocks")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
The audio module clocks are supposed to be set according to the sample
rate of the audio stream. The audio PLL provides the clock signal for
these module clocks, and only it is freely tunable.
Set CLK_SET_RATE_PARENT for the audio module clocks so their users can
properly tune the clock rate.
Fixes: 5690879d93 ("clk: sunxi-ng: Add A23 CCU")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Add the A64 CCU clocks set.
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Allow the CCU drivers to specify a multiplier for their clocks.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Modify the current clocks we have to be able to specify the minimum for
each clocks we support, just like we support the max.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Some clocks still use an explicit list of arguments, which make it a bit
more tedious to add new parameters.
Convert those over to a structure pointer argument to add as many
arguments as possible without having to many noise in our patches, or a
very long list of arguments.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
While the rational library works great, it doesn't really allow us to add
more constraints, like the minimum.
Remove that in order to be able to deal with the constraints we'll need.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Rename the structures meant to be embedded in other structures to make it
consistent with the mux structure name
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
On the A31, the DMA engine only works if AHB1 is clocked from PLL6.
In addition, the hstimer is clocked from AHB1, and if AHB1 is clocked
from the CPU clock, and cpufreq is working, we get an unstable timer.
Force the AHB1 clock to use PLL6 as its parent. Previously this was done
in the device tree with the assigned-clocks and assigned-clocks-parent
bindings. However with this new monolithic driver, the system critical
clocks aren't exported through the device tree. The alternative is to
force this setting in the driver before the clocks are registered.
This is also done in newer versions of mainline U-boot. But people still
using an older version, or even the vendor version, can still hit this
issue. Hence the need to do it in the kernel as well.
Reported-by: Hans de Goede <hdegoede@redhat.com>
Reported-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Fixes: c6e6c96d8f ("clk: sunxi-ng: Add A31/A31s clocks")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
There's been a copy and paste mistake in the A23 and A33 from the H3,
leading in the reset offset for the UART and I2C.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
The register offset for the mipi-csi clk is off by 4, a copy paste
error from the mipi-dsi clk.
Fixes: c6e6c96d8f ("clk: sunxi-ng: Add A31/A31s clocks")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
The PLLs have a "lock" bit in their configuration registers which
indicate if the PLL has locked on to the requested clock rate. We
check this bit in the .set_rate op. The PLL cannot lock on if it's
not running, which might be a false positive (warning).
Set the CLK_SET_RATE_UNGATE flag for all PLLs so whenever clk_set_rate
is called on them, they get enabled and the "lock" check is really
checking the PLL.
Fixes: c6e6c96d8f ("clk: sunxi-ng: Add A31/A31s clocks")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
The LCD controller and HDMI controller use the LCDx-CHy and HDMI clocks
to generate their dot clocks. To be able to generate a full range of
possible clock rates, the parent PLL clock rates should also be changed.
Fixes: c6e6c96d8f ("clk: sunxi-ng: Add A31/A31s clocks")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Four more SoCs converted to the new clock framework (A31, A31s, A23 and
A33).
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Merge tag 'sunxi-clk-for-4.9' of https://git.kernel.org/pub/scm/linux/kernel/git/mripard/linux into clk-next
Pull Allwinner clock driver changes from Maxime Ripard:
Four more SoCs converted to the new clock framework (A31, A31s, A23 and
A33).
* tag 'sunxi-clk-for-4.9' of https://git.kernel.org/pub/scm/linux/kernel/git/mripard/linux:
clk: sunxi-ng: Add hardware dependency
clk: sunxi-ng: Add A23 CCU
clk: sunxi-ng: Add A33 CCU support
clk: sunxi-ng: Add N-class clocks support
clk: sunxi-ng: mux: Add mux table macro
clk: sunxi-ng: div: Allow to set a maximum
clk: sunxi-ng: div: Add kerneldoc for the _ccu_div structure
clk: sunxi-ng: div: Add mux table macros
clk: sunxi-ng: Add A31/A31s clocks
clk: sunxi-ng: mux: Add clk notifier functions
clk: sunxi-ng: mux: support fixed pre-dividers on multiple parents
clk: sunxi-ng: mux: Add support for mux tables
clk: sunxi-ng: mux: Rename mux macro to be consistent
clk: sunxi-ng: nkm: Add mux to support multiple parents
clk: sunxi-ng: mux: Increase fixed pre-divider div size
The sunxi-ng clock driver is useless for other architectures.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Add support for the clock unit found in the A23. Due to the similarities
with the A33, it also shares its clock IDs to allow sharing the DTSI.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
This commit introduces the clocks found in the Allwinner A33 CCU.
Since this SoC is very similar to the A23, and we share a significant share
of the DTSI, the clock IDs that are going to be used will also be shared
with the A23, hence the name of the various header files.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Add support for the class with a single factor, N, being a multiplier.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Add a new macro to declare muxes based on a table and a gate.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Some dividers might have a maximum value that is lower than the width of
the register.
Add a field to _ccu_div to handle those case properly. If the field is set
to 0, the code will assume that the maximum value is the maximum one that
can be used with the field register width.
Otherwise, we'll use whatever value has been set.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
