clk: qcom: clk-rcg2: Fix clock rate overflow for high parent frequencies

If the parent clock rate is greater than unsigned long max/2 then
integer overflow happens when calculating the clock rate on 32-bit systems.
As RCG2 uses half integer dividers, the clock rate is first being
multiplied by 2 which will overflow the unsigned long max value.
Hence, replace the common pattern of doing 64-bit multiplication
and then a do_div() call with simpler mult_frac call.

Fixes: bcd61c0f535a ("clk: qcom: Add support for root clock generators (RCGs)")
Signed-off-by: Devi Priya <quic_devipriy@quicinc.com>
Reviewed-by: Marijn Suijten <marijn.suijten@somainline.org>
Link: https://lore.kernel.org/r/20230901073640.4973-1-quic_devipriy@quicinc.com
[bjorn: Also drop unnecessary {} around single statements]
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

clk: qcom: rcg2: Make hw_clk_ctrl toggleable

Certain SoCs use the HW_CLK_CTRL feature on some of the clocks they
host. This allows the clocks to be turned on automatically when a
downstream branch tries to change rate or config.

Make it togglable so that we can utilize this.

Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230517-topic-waipio-gpucc-v1-2-4f40e282af1d@linaro.org

clk: qcom: clk-rcg2: Take clock boundaries into consideration for gfx3d

The gfx3d clock is hand-crafting its own clk_rate_request in
clk_gfx3d_determine_rate to pass to the parent of that clock.

However, since the clk_rate_request is zero'd at creation, it will have
a max_rate of 0 which will break any code depending on the clock
boundaries.

That includes the recent commit 948fb0969eae ("clk: Always clamp the
rounded rate") which will clamp the rate given to clk_round_rate() to
the current clock boundaries.

For the gfx3d clock, it means that since both the min_rate and max_rate
fields are set at zero, clk_round_rate() now always return 0.

Let's initialize the min_rate and max_rate fields properly for that
clock.

Fixes: 948fb0969eae ("clk: Always clamp the rounded rate")
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220816112530.1837489-25-maxime@cerno.tech
Tested-by: Linux Kernel Functional Testing <lkft@linaro.org>
Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: qcom: clk-rcg2: add rcg2 mux ops

An RCG may act as a mux that switch between 2 parents.
This is the case on IPQ6018 and IPQ8074 where the APCS core clk that feeds
the CPU cluster clock just switches between XO and the PLL that feeds it.

Add the required ops to add support for this special configuration and use
the generic mux function to determine the rate.

This way we dont have to keep a essentially dummy frequency table to use
RCG2 as a mux.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Signed-off-by: Robert Marko <robimarko@gmail.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20220818220628.339366-1-robimarko@gmail.com

clk: qcom: clk-rcg2: Make sure to not write d=0 to the NMD register

Sometimes calculation of d value may result in 0 because of the
rounding after integer division. This causes the following error:

[ 113.969689] camss_gp1_clk_src: rcg didn't update its configuration.
[ 113.969754] WARNING: CPU: 3 PID: 35 at drivers/clk/qcom/clk-rcg2.c:122 update_config+0xc8/0xdc

Make sure that D value is never zero.

Fixes: 7f891faf596e ("clk: qcom: clk-rcg2: Add support for duty-cycle for RCG")
Signed-off-by: Nikita Travkin <nikita@trvn.ru>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220612145955.385787-3-nikita@trvn.ru

clk: qcom: clk-rcg2: Fail Duty-Cycle configuration if MND divider is not enabled.

In cases when MND is not enabled (e.g. when only Half Integer Divider is
used), setting D registers makes no effect.

Fail instead of making ineffective write.

Fixes: 7f891faf596e ("clk: qcom: clk-rcg2: Add support for duty-cycle for RCG")
Signed-off-by: Nikita Travkin <nikita@trvn.ru>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220612145955.385787-2-nikita@trvn.ru

clk: qcom: rcg2: Cache CFG register updates for parked RCGs

As GDSCs are turned on and off some associated clocks are momentarily
enabled for house keeping purposes. For this, and similar, purposes the
"shared RCGs" will park the RCG on a source clock which is known to be
available.
When the RCG is parked, a safe clock source will be selected and
committed, then the original source would be written back and upon enable
the change back to the unparked source would be committed.

But starting with SM8350 this fails, as the value in CFG is committed by
the GDSC handshake and without a ticking parent the GDSC enablement will
time out.

This becomes a concrete problem if the runtime supended state of a
device includes disabling such rcg's parent clock. As the device
attempts to power up the domain again the rcg will fail to enable and
hence the GDSC enablement will fail, preventing the device from
returning from the suspended state.

This can be seen in e.g. the display stack during probe on SM8350.

To avoid this problem, the software needs to ensure that the RCG is
configured to a active parent clock while it is disabled. This is done
by caching the CFG register content while the shared RCG is parked on
this safe source.

Writes to M, N and D registers are committed as they are requested. New
helpers for get_parent() and recalc_rate() are extracted from their
previous implementations and __clk_rcg2_configure() is modified to allow
it to operate on the cached value.

Fixes: 7ef6f11887bd ("clk: qcom: Configure the RCGs to a safe source as needed")
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lore.kernel.org/r/20220426212136.1543984-1-bjorn.andersson@linaro.org

clk: qcom: clk-rcg2: fix gfx3d frequency calculation

Since the commit 948fb0969eae ("clk: Always clamp the rounded rate"),
the clk_core_determine_round_nolock() would clamp the requested rate
between min and max rates from the rate request. Normally these fields
would be filled by clk_core_get_boundaries() called from
clk_round_rate().

However clk_gfx3d_determine_rate() uses a manually crafted rate request,
which did not have these fields filled. Thus the requested frequency
would be clamped to 0, resulting in weird frequencies being requested
from the hardware.

Fix this by filling min_rate and max_rate to the values valid for the
respective PLLs (0 and ULONG_MAX).

Fixes: 948fb0969eae ("clk: Always clamp the rounded rate")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20220419235447.1586192-1-dmitry.baryshkov@linaro.org
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reported-by: Rob Clark <robdclark@chromium.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: qcom: clk-rcg2: Update the frac table for pixel clock

Support the new numerator and denominator for pixel clock on SM8350 and
support rgb101010, RGB888 use cases on SM8450.

Fixes: 99cbd064b059f ("clk: qcom: Support display RCG clocks")
Signed-off-by: Taniya Das <tdas@codeaurora.org>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220227175536.3131-2-tdas@codeaurora.org

clk: qcom: clk-rcg2: Update logic to calculate D value for RCG

The display pixel clock has a requirement on certain newer platforms to
support M/N as (2/3) and the final D value calculated results in
underflow errors.
As the current implementation does not check for D value is within
the accepted range for a given M & N value. Update the logic to
calculate the final D value based on the range.

Fixes: 99cbd064b059f ("clk: qcom: Support display RCG clocks")
Signed-off-by: Taniya Das <tdas@codeaurora.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220227175536.3131-1-tdas@codeaurora.org

clk: qcom: clk-rcg2: Add support for duty-cycle for RCG

The root clock generators with MND divider has the capability to support
change in duty-cycle by updating the 'D'. Add the clock ops which would
check all the boundary conditions and enable setting the desired duty-cycle
as per the consumer.

Signed-off-by: Taniya Das <tdas@codeaurora.org>
Link: https://lore.kernel.org/r/1619334502-9880-2-git-send-email-tdas@codeaurora.org
[sboyd@kernel.org: Remove _val everywhere]
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: qcom: rcg2: Rectify clk_gfx3d rate rounding without mux division

In case the mux is not divided parent_req was mistakenly not assigned to
leading __clk_determine_rate to determine the best frequency setting for
a requested rate of 0, resulting in the msm8996 platform not booting.
Rectify this by refactoring the logic to unconditionally assign to
parent_req.rate with the clock rate the caller is expecting.

Fixes: 7cbb78a99db6 ("clk: qcom: rcg2: Stop hardcoding gfx3d pingpong parent numbers")
Reported-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Tested-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Reviewed-By: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Link: https://lore.kernel.org/r/20210302234106.3418665-1-marijn.suijten@somainline.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: qcom: rcg2: Stop hardcoding gfx3d pingpong parent numbers

The function clk_gfx3d_determine_rate is selecting different PLLs
to manage the GFX3D clock source in a special way: this one needs
to be ping-pong'ed on different PLLs to ensure stability during
frequency switching (set a PLL rate, let it stabilize, switch the
RCG to the new PLL) and fast frequency transitions.

This technique is currently being used in the MSM8996 SoC and the
function was assuming that the parents were always at a specific
index in the parents list, which is TRUE, if we use this only on
the MSM8996 MMCC.
Unfortunately, MSM8996 is not the only SoC that needs to ping-pong
the graphics RCG, so choices are:
1. Make new special ops just to hardcode *again* other indexes,
creating code duplication for (imo) no reason; or
2. Generalize this function, so that it becomes usable for a range
of SoCs with slightly different ping-pong configuration.

In this commit, the second road was taken: define a new "special"
struct clk_rcg2_gfx3d, containing the ordered list of parents to
ping-pong the graphics clock on, and the "regular" rcg2 clock
structure in order to generalize the clk_gfx3d_determine_rate
function and make it working for other SoCs.

As for the function itself it is left with the assumption that we
need to ping-pong over three parents. The reasons for this are:
1. The initial model was MSM8996, which has 3 parents for the
graphics clock pingpong;
2. The other example that was taken into consideration is the
SDM630/636/660 SoC gpu clock controller, which is ping-ponging
over two dynamic clocked and one fixed clock PLL.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Link: https://lore.kernel.org/r/20210113183817.447866-6-angelogioacchino.delregno@somainline.org
[sboyd@kernel.org: Grow some local variables, drop do_div() usage in
favor of plain division, we're not dealing with a u64 here]
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: qcom: dispcc: Update DP clk ops for phy design

The clk_rcg2_dp_determine_rate() function is used for the DP pixel clk.
This function should return the rate that can be achieved by the pixel
clk in 'struct clk_rate_request::rate' and match the logic similar to
what is seen in clk_rcg2_dp_set_rate(). But that isn't the case. Instead
the code merely bubbles the rate request up to the parent of the pixel
clk and doesn't try to do a rational approximation of the rate that
would be achieved by picking some m/n value for the RCG.

Let's change this logic so that we can assume the parent clk frequency
is fixed (it is because it's the VCO of the DP PLL that is configured
based on the link rate) and so that we can calculate what the m/n value
will be and adjust the req->rate appropriately.

Cc: Jeykumar Sankaran <jsanka@codeaurora.org>
Cc: Chandan Uddaraju <chandanu@codeaurora.org>
Cc: Vara Reddy <varar@codeaurora.org>
Cc: Tanmay Shah <tanmay@codeaurora.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Manu Gautam <mgautam@codeaurora.org>
Cc: Sandeep Maheswaram <sanm@codeaurora.org>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Jonathan Marek <jonathan@marek.ca>
Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Cc: Rob Clark <robdclark@chromium.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20200916231202.3637932-10-swboyd@chromium.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: qcom: rcg2: Don't crash if our parent can't be found; return an error

When I got my clock parenting slightly wrong I ended up with a crash
that looked like this:

Unable to handle kernel NULL pointer dereference at virtual
address 0000000000000000
...
pc : clk_hw_get_rate+0x14/0x44
...
Call trace:
clk_hw_get_rate+0x14/0x44
_freq_tbl_determine_rate+0x94/0xfc
clk_rcg2_determine_rate+0x2c/0x38
clk_core_determine_round_nolock+0x4c/0x88
clk_core_round_rate_nolock+0x6c/0xa8
clk_core_round_rate_nolock+0x9c/0xa8
clk_core_set_rate_nolock+0x70/0x180
clk_set_rate+0x3c/0x6c
of_clk_set_defaults+0x254/0x360
platform_drv_probe+0x28/0xb0
really_probe+0x120/0x2dc
driver_probe_device+0x64/0xfc
device_driver_attach+0x4c/0x6c
__driver_attach+0xac/0xc0
bus_for_each_dev+0x84/0xcc
driver_attach+0x2c/0x38
bus_add_driver+0xfc/0x1d0
driver_register+0x64/0xf8
__platform_driver_register+0x4c/0x58
msm_drm_register+0x5c/0x60
...

It turned out that clk_hw_get_parent_by_index() was returning NULL and
we weren't checking. Let's check it so that we don't crash.

Fixes: ac269395cdd8 ("clk: qcom: Convert to clk_hw based provider APIs")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Link: https://lkml.kernel.org/r/20200203103049.v4.1.I7487325fe8e701a68a07d3be8a6a4b571eca9cfa@changeid
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: qcom: Don't overwrite 'cfg' in clk_rcg2_dfs_populate_freq()

The DFS frequency table logic overwrites 'cfg' while detecting the
parent clk and then later on in clk_rcg2_dfs_populate_freq() we use that
same variable to figure out the mode of the clk, either MND or not. Add
a new variable to hold the parent clk bit so that 'cfg' is left
untouched for use later.

This fixes problems in detecting the supported frequencies for any clks
in DFS mode.

Fixes: cc4f6944d0e3 ("clk: qcom: Add support for RCG to register for DFS")
Reported-by: Rajendra Nayak <rnayak@codeaurora.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lkml.kernel.org/r/20200128193329.45635-1-sboyd@kernel.org
Tested-by: Rajendra Nayak <rnayak@codeaurora.org>

clk: qcom: rcg2: Add support for display port clock ops

New display port clock ops supported for display port clocks.

Signed-off-by: Taniya Das <tdas@codeaurora.org>
Link: https://lkml.kernel.org/r/20190731182713.8123-2-tdas@codeaurora.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: qcom: Allow constant ratio freq tables for rcg

Some RCGs (the gfx_3d_src_clk in msm8998 for example) are basically just
some constant ratio from the input across the entire frequency range. It
would be great if we could specify the frequency table as a single entry
constant ratio instead of a long list, ie:

{ .src = P_GPUPLL0_OUT_EVEN, .pre_div = 3 },
{ }

So, lets support that.

We need to fix a corner case in qcom_find_freq() where if the freq table
is non-null, but has no frequencies, we end up returning an "entry" before
the table array, which is bad. Then, we need ignore the freq from the
table, and instead base everything on the requested freq.

Suggested-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Jeffrey Hugo <jeffrey.l.hugo@gmail.com>
Link: https://lkml.kernel.org/r/20191031185715.15504-1-jeffrey.l.hugo@gmail.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: qcom: remove unneeded semicolon

remove unneeded semicolon.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lkml.kernel.org/r/20191025093332.27592-1-yuehaibing@huawei.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: qcom: rcg: Return failure for RCG update

In case of update config failure, return -EBUSY, so that consumers could
handle the failure gracefully.

Signed-off-by: Taniya Das <tdas@codeaurora.org>
Link: https://lkml.kernel.org/r/1557339895-21952-2-git-send-email-tdas@codeaurora.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: qcom: Remove error prints from DFS registration

These aren't useful and they reference the init structure name. Let's
just drop them.

Cc: Taniya Das <tdas@codeaurora.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lkml.kernel.org/r/20190815160020.183334-5-sboyd@kernel.org
Acked-by: Taniya Das <tdas@codeaurora.org>

clk: qcom: clk-rcg2: Introduce a cfg offset for RCGs

The RCG CFG/M/N/D register base could be at a different offset than
the CMD register, so introduce a cfg_offset to identify the offset
with respect to the CMD RCGR register.

Signed-off-by: Taniya Das <tdas@codeaurora.org>
Signed-off-by: Anu Ramanathan <anur@codeaurora.org>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: qcom: Allocate space for NULL terimation in DFS table

The table allocated in clk_rcg2_dfs_populate_freq_table() is
eventually iterated over by qcom_find_freq() which assumes that the
table is NULL terminated. Allocate one extra space in the array for
the NULL termination. Initting of the NULL termination is implicit
due to kcalloc().

Fixes: cc4f6944d0e3 ("clk: qcom: Add support for RCG to register for DFS")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: qcom: Add support for RCG to register for DFS

Dynamic Frequency switch is a feature of clock controller by which request
from peripherals allows automatic switching frequency of input clock
without SW intervention. There are various performance levels associated
with a root clock. When the input performance state changes, the source
clocks and division ratios of the new performance state are loaded on to
RCG via HW and the RCG switches to new clock frequency when the RCG is in
DFS HW enabled mode.

Register the root clock generators(RCG) to switch to use the dfs clock ops
in the cases where DFS is enabled. The clk_round_rate() called by the clock
consumer would invoke the dfs determine clock ops and would read the DFS
performance level registers to identify all the frequencies supported and
update the frequency table. The DFS clock consumers would maintain these
frequency mapping and request the desired performance levels.

Signed-off-by: Taniya Das <tdas@codeaurora.org>
[sboyd@kernel.org: Rework registration logic to stop copying, change
recalc_rate() to index directly into the table if possible and fallback
to calculating on the fly with an assumed correct parent]
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: qcom: Base rcg parent rate off plan frequency

_freq_tbl_determine_rate uses the pre_div found in the clock plan
multiplied by the requested rate from the caller to determine the
best parent rate to set. If the requested rate is not exactly equal
to the rate that was found in the clock plan, then using the requested
rate in parent rate calculations is incorrect. For instance, if 150MHz
was requested, but 200MHz was the match found, and that plan had a
pre_div of 3, then the parent should be set to 600MHz, not 450MHz.

Signed-off-by: Evan Green <evgreen@chromium.org>
Fixes: bcd61c0f535a ("clk: qcom: Add support for root clock generators (RCGs)")
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: qcom: Configure the RCGs to a safe source as needed

For some root clock generators, there could be child branches which are
controlled by an entity other than application processor subsystem. For
such RCGs, as per application processor subsystem clock driver, all of
its downstream clocks are disabled and RCG is in disabled state but in
reality downstream clocks can be left enabled before.

So in this scenario, when RCG is disabled as per clock driver's point of
view and when rate scaling request comes before downstream clock enable
request, then RCG fails to update its configuration because in reality
RCG is on and it expects its new source to already be in enable state but
in reality new source is off. In order to avoid having the RCG to go into
an invalid state, add support to update the CFG, M, N and D registers
during set_rate() without configuration update and defer the actual RCG
configuration update to be done during clk_enable() as at this point of
time, both its new parent and safe source will be already enabled and RCG
can safely switch to new parent.

During clk_disable() request, configure it to safe source as both its
parents, safe source and current parent will be enabled and RCG can
safely execute a switch.

Signed-off-by: Taniya Das <tdas@codeaurora.org>
Signed-off-by: Amit Nischal <anischal@codeaurora.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: qcom: Clear hardware clock control bit of RCG

For upcoming targets like sdm845, POR value of the hardware clock control
bit is set for most of root clocks which needs to be cleared for software
to be able to control. For older targets like MSM8996, this bit is reserved
bit and having POR value as 0 so this patch will work for the older targets
too. So update the configuration mask to take care of the same to clear
hardware clock control bit.

Signed-off-by: Amit Nischal <anischal@codeaurora.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: qcom: Remove unused RCG ops

The RCGs ops for shared branches are not used now, so remove it.

Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: qcom: Add rcg ops to return floor value closest to the requested rate

The default behaviour with clk_rcg2_ops is for the
clk_round_rate()/clk_set_rate() to return/set a ceil clock
rate closest to the requested rate by looking up the corresponding
frequency table.
However, we do have some instances (mainly sdcc on various platforms)
of clients expecting a clk_set_rate() to set a floor value instead.
Add a new clk_rcg2_floor_ops to handle this for such specific
rcg instances

Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org>
Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: qcom: Add gfx3d ping-pong PLL frequency switching

The GPU clocks on msm8996 have three dedicated PLLs, MMPLL2,
MMPLL8, and MMPLL9. We leave MMPLL9 at the maximum speed (624
MHz), and we use MMPLL2 and MMPLL8 for the other frequencies. To
make switching frequencies faster, we ping-pong between MMPLL2
and MMPLL8 when we're switching between frequencies that aren't
the maximum. Implement custom rcg clk ops for this type of
frequency switching.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: qcom: Add support for RCGs with shared branches

Some root clock generators may have child branches that are controlled
by different CPUs. These RCGs require some special operations:
- some enable bits have to be toggled when we set the rate;
- if RCG is disabled we only cache the rate and set it later when enabled;
- when the RCG is disabled, the mux is set to the safe source;

Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>
[sboyd@codeaurora.org: Simplify recalc_rate implementation]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: qcom: Allow clk_set_parent() to work on display clocks

Sometimes the display driver may want to change the parent PLL of
the display clocks (byte and pixel clocks) depending on the
use-case. Currently the parent is fixed by means of having a
frequency table with one entry that chooses a particular parent.
Remove this restriction and use the parent the clock is
configured for in the hardware during clk_set_rate(). This
requires consumers to rely on the default parent or to configure
the parent with clk_set_parent()/assigned-clock-parents on the
clocks before calling clk_set_rate().

Tested-by: Archit Taneja <architt@codeaurora.org>
Cc: Hai Li <hali@codeaurora.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: qcom: Convert to clk_hw based provider APIs

We're removing struct clk from the clk provider API, so switch
this code to using the clk_hw based provider APIs.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: Convert __clk_get_flags() to clk_hw_get_flags()

Mostly converted with the following snippet:

@@
struct clk_hw *E;
@@

-__clk_get_flags(E->clk)
+clk_hw_get_flags(E)

Acked-by: Tero Kristo <t-kristo@ti.com>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Acked-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Coquelin <mcoquelin.stm32@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: Replace __clk_get_num_parents with clk_hw_get_num_parents()

Mostly converted with the following semantic patch:

@@
struct clk_hw *E;
@@

-__clk_get_num_parents(E->clk)
+clk_hw_get_num_parents(E)

Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Cc: Chao Xie <chao.xie@marvell.com>
Cc: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Cc: Tomasz Figa <tomasz.figa@gmail.com>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: "Emilio López" <emilio@elopez.com.ar>
Acked-by: Tero Kristo <t-kristo@ti.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: change clk_ops' ->determine_rate() prototype

Clock rates are stored in an unsigned long field, but ->determine_rate()
(which returns a rounded rate from a requested one) returns a long
value (errors are reported using negative error codes), which can lead
to long overflow if the clock rate exceed 2Ghz.

Change ->determine_rate() prototype to return 0 or an error code, and pass
a pointer to a clk_rate_request structure containing the expected target
rate and the rate constraints imposed by clk users.

The clk_rate_request structure might be extended in the future to contain
other kind of constraints like the rounding policy, the maximum clock
inaccuracy or other things that are not yet supported by the CCF
(power consumption constraints ?).

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
CC: Jonathan Corbet <corbet@lwn.net>
CC: Tony Lindgren <tony@atomide.com>
CC: Ralf Baechle <ralf@linux-mips.org>
CC: "Emilio López" <emilio@elopez.com.ar>
CC: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Tero Kristo <t-kristo@ti.com>
CC: Peter De Schrijver <pdeschrijver@nvidia.com>
CC: Prashant Gaikwad <pgaikwad@nvidia.com>
CC: Stephen Warren <swarren@wwwdotorg.org>
CC: Thierry Reding <thierry.reding@gmail.com>
CC: Alexandre Courbot <gnurou@gmail.com>
CC: linux-doc@vger.kernel.org
CC: linux-kernel@vger.kernel.org
CC: linux-arm-kernel@lists.infradead.org
CC: linux-omap@vger.kernel.org
CC: linux-mips@linux-mips.org
CC: linux-tegra@vger.kernel.org
[sboyd@codeaurora.org: Fix parent dereference problem in
__clk_determine_rate()]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Tested-by: Romain Perier <romain.perier@gmail.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
[sboyd@codeaurora.org: Folded in fix from Heiko for fixed-rate
clocks without parents or a rate determining op]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: qcom: Use parent rate when set rate to pixel RCG clock

Since the parent rate has been recalculated, pixel RCG clock
should rely on it to find the correct M/N values during set_rate,
instead of calling __clk_round_rate() to its parent again.

Signed-off-by: Hai Li <hali@codeaurora.org>
Tested-by: Archit Taneja <architt@codeaurora.org>
Fixes: 99cbd064b059 ("clk: qcom: Support display RCG clocks")
[sboyd@codeaurora.org: Silenced unused parent variable warning]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: qcom: Fix parent_map translations

When we introduced the parent_map tables, we missed to update
some of the functions where mapping is translated. Fix this.

Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>
Tested-by: Nicolas Dechesne <nicolas.dechesne@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: qcom: Introduce parent_map tables

In the current parent mapping code, we can get duplicate or inconsistent
indexes, which leads to discrepancy between the number of elements in the
array and the number of parents. Until now, this was solved with some
reordering but this is not always possible.

This patch introduces index tables that are used to define the relations
between the PLL source and the hardware mux configuration value.
To accomplish this, here we do the following:
- Define a parent_map struct to map the relations between PLL source index
and register configuration value.
- Add a qcom_find_src_index() function for finding the index of a clock
matching the specific PLL configuration.
- Update the {set,get}_parent RCG functions use the newly introduced
parent_map struct.
- Convert all existing drivers to the new parent_map tables.

Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: qcom: Fix clk_get_parent function return value

According to the common clock framework API, the clk_get_parent() function
should return u8. Currently we are returning negative values on error. Fix
this and use the default parent in case of an error.

Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: qcom: fix RCG M/N counter configuration

Currently, a RCG's M/N counter (used for fraction division) is
set to either 'bypass' (counter disabled) or 'dual edge' (counter
enabled) based on whether the corresponding rcg struct has a mnd
field specified and a non-zero N.

In the case where M and N are the same value, the M/N counter is
still enabled by code even though no division takes place.
Leaving the RCG in such a state can result in improper behavior.
This was observed with the DSI pixel clock RCG when M and N were
both set to 1.

Add an additional check (M != N) to enable the M/N counter only
when it's needed for fraction division.

Signed-off-by: Archit Taneja <architt@codeaurora.org>
Fixes: bcd61c0f535a (clk: qcom: Add support for root clock
generators (RCGs))
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: Add rate constraints to clocks

Adds a way for clock consumers to set maximum and minimum rates. This
can be used for thermal drivers to set minimum rates, or by misc.
drivers to set maximum rates to assure a minimum performance level.

Changes the signature of the determine_rate callback by adding the
parameters min_rate and max_rate.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
[sboyd@codeaurora.org: set req_rate in __clk_init]
Signed-off-by: Michael Turquette <mturquette@linaro.org>
[mturquette@linaro.org: min/max rate for sun6i_ahb1_clk_determine_rate
migrated clk-private.h changes to clk.c]

clk: Change clk_ops->determine_rate to return a clk_hw as the best parent

This is in preparation for clock providers to not have to deal with struct clk.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>

clk: qcom: Consolidate frequency finding logic

There are two find_freq() functions in clk-rcg.c and clk-rcg2.c
that are almost exactly the same. Consolidate them into one
function to save on some code space.

Cc: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: qcom: Support display RCG clocks

Add support for the DSI/EDP/HDMI RCG clocks. With the proper
display driver in place this should allow us to support display
clocks on msm8974 based devices.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

clk: qcom: Return highest rate when round_rate() exceeds plan

Some drivers may want to call clk_set_rate() with a very large
number to force the clock to go as fast as it possibly can
without having to know the range between the highest rate and
second highest rate. Add support for this by defaulting to the
highest rate in the frequency table if we can't find a frequency
greater than what is requested.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

clk: qcom: Fix clk_rcg2_is_enabled() check

If the bit is set the clock is off so we should be checking for
a clear bit, not a set bit. Invert the logic.

Fixes: bcd61c0f535a (clk: qcom: Add support for root clock generators (RCGs))
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

clk: qcom: Add support for root clock generators (RCGs)

Add support for the root clock generators on Qualcomm devices.
RCGs are highly customizable mux/divider/counter clocks that can
be used to generate almost any rate desired given some input
source that is faster than the desired rate.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>