Commit Graph

259 Commits

Author SHA1 Message Date
Jerome Brunet
6d6d2a24b2 clk: meson: axg-audio: don't register inputs in the onecell data
Clock inputs should not be exported outside the controller. It is a hack
to have a stable global clock name within the clock controller, even for
clocks external to the controller.

There is an ongoing effort to replace this hack with something better.
The first step is to not register those clocks in the provider anymore,
so we can completely remove them later on.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20190329160649.31603-4-jbrunet@baylibre.com
2019-04-08 09:58:41 +02:00
Jerome Brunet
b18819c4ac clk: meson: axg_audio: replace prefix axg by aud
The audio clock controller is compatible with axg and g12a SoC family.
Having each clock name prefixed with "axg_" looks weird on the g12a.
This change replace the "axg_" by "aud_" in fron the clock names.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20190329160649.31603-3-jbrunet@baylibre.com
2019-04-08 09:58:25 +02:00
Martin Blumenstingl
90751f686e clk: meson: meson8b: add the video decoder clock trees
This adds the four video decoder clock trees.

VDEC_1 is split into two paths on Meson8b and Meson8m2:
- input mux called "vdec_1_sel"
- two dividers ("vdec_1_1_div" and "vdec_1_2_div") and gates ("vdec_1_1"
  and "vdec_1_2")
- and an output mux (probably glitch-free) called "vdec_1"
On Meson8 the VDEC_1 tree is simpler because there's only one path:
- input mux called "vdec_1_sel"
- divider ("vdec_1_1_div") and gate ("vdec_1_1")
- (the gate is used as output directly, there's no mux)

The VDEC_HCODEC and VDEC_2 clocks are simple composite clocks each
consisting of an input mux, divider and a gate.

The VDEC_HEVC clock seems to have two paths similar to the VDEC_1 clock.
However, the register offsets of the second clock path is not known.
Amlogic's 3.10 kernel (which is used as reference) sets
HHI_VDEC2_CLK_CNTL[31] to 1 before changing the VDEC_HEVC clock and back
to 0 afterwards. For now, leave a TODO comment and only add the first
path.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Maxime Jourdan <mjourdan@baylibre.com>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20190324151423.19063-3-martin.blumenstingl@googlemail.com
2019-04-01 13:34:29 +02:00
Martin Blumenstingl
41785ce562 clk: meson: meson8b: add the VPU clock trees
The VPU clock tree is slightly different on all three supported SoCs:

Meson8 only has an input mux (which chooses between "fclk_div4",
"fclk_div3", "fclk_div5" and "fclk_div7"), a divider and a gate.

Meson8b has two VPU clock trees, each with an input mux (using the same
parents as the input mux on Meson8), divider and a gates. The final VPU
clock is a glitch-free mux which chooses between VPU_1 and VPU_2.

Meson8m2 uses a similar clock tree as Meson8b but the last input clock
is different: instead of using "fclk_div7" as input Meson8m2 uses
"gp_pll". This was probably done in hardware to improve the accuracy of
the clock because fclk_div7 gives us 2550MHz / 7 = 364.286MHz while
GP_PLL can achieve 364.0MHz.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20190324151104.18397-5-martin.blumenstingl@googlemail.com
2019-04-01 13:34:20 +02:00
Martin Blumenstingl
b882964b37 clk: meson: meson8b: add support for the GP_PLL clock on Meson8m2
Meson8m2 has a GP_PLL clock (similar to GP0_PLL on GXBB/GXL/GXM) which
is used as input for the VPU clocks.
The only supported frequency (based on Amlogic's vendor kernel sources)
is 364MHz which is achieved using the following parameters:
- input: XTAL (24MHz)
- M = 182
- N = 3
- OD = 2 ^ 2

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20190324151104.18397-4-martin.blumenstingl@googlemail.com
2019-04-01 13:34:09 +02:00
Martin Blumenstingl
32cd198a1a clk: meson: meson8b: use a separate clock table for Meson8m2
Meson8, Meson8b and Meson8m2 implement a similar clock controller.
However, there are a few differences between the three actual IP blocks.

One example where Meson8m2 differs from Meson8b is the VPU clock setup:
- the VPU input mux can choose between "fclk_div4", "fclk_div3",
  "fclk_div5" and "fclk_div7" on Meson8b
- however, on Meson8m2 it can choose between "fclk_div4", "fclk_div3",
  "fclk_div5" and "gp_pll" (GP_PLL only exists on Meson8m2, it's the
  predecessor of the GP0_PLL clock on GXBB/GXL/GXM))

Add a separate clk_hw_onecell_data table for Meson8m2 so these
differences can be implemented in our clock controller driver. For now
meson8m2_hw_onecell_data is a clone of our existing
meson8b_hw_onecell_data.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20190324151104.18397-3-martin.blumenstingl@googlemail.com
2019-04-01 13:33:52 +02:00
Maxime Jourdan
4b0f73055a clk: meson-g12a: add video decoder clocks
Add the necessary clock parts for:

 - VDEC_1: used to feed VDEC_1
 - VDEC_HEVC: the "back" part of the VDEC_HEVC block
 - VDEC_HEVCF: the "front" part of the VDEC_HEVC block

In previous SoC generations (GXL, GXBB), there was only one VDEC_HEVC
clock, which got split in two parts for G12A.

Signed-off-by: Maxime Jourdan <mjourdan@baylibre.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20190319101138.27520-2-mjourdan@baylibre.com
2019-04-01 10:45:11 +02:00
Neil Armstrong
34775209ba clk: meson-g12a: add PCIE PLL clocks
Add the PCIe reference clock feeding the USB3 + PCIE combo PHY.

This PLL needs a very precise register sequence to permit to be locked,
thus using the specific clk-pll pcie ops.

The PLL is then followed by :
- a fixed /2 divider
- a 5-bit 1-based divider
- a final /2 divider

This reference clock is fixed to 100MHz, thus only a single PLL setup
is added.

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lkml.kernel.org/r/20190307141455.23879-4-narmstrong@baylibre.com
2019-04-01 10:45:11 +02:00
Neil Armstrong
39b8500283 clk: meson-pll: add reduced specific clk_ops for G12A PCIe PLL
The Meson G12A PCIE PLL is fined tuned to deliver a very precise
100MHz reference clock for the PCIe Analog PHY, and thus requires
a strict register sequence to enable the PLL.
To simplify, use the _init() op to enable the PLL and keep
the other ops except set_rate since the rate is fixed.

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lkml.kernel.org/r/20190307141455.23879-2-narmstrong@baylibre.com
2019-04-01 10:45:11 +02:00
Neil Armstrong
370294e266 clk: meson: g12a: add cpu clocks
Add the Amlogic G12A Family CPU Clock tree in read/only for now.

The CPU clock can either use the SYS_PLL for > 1GHz frequencies or
use a couple of div+mux from 1GHz/667MHz/24MHz source with 2 non-glitch
muxes.

Proper DVFS support will come in a second time.

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
[narmstrong: fixed cpu clocks namings]
Link: https://lkml.kernel.org/r/20190304131129.7762-3-narmstrong@baylibre.com
2019-04-01 10:45:11 +02:00
Neil Armstrong
133bb341b9 dt-bindings: clock: g12a-aoclk: expose CLKID_AO_CTS_OSCIN
When submitted v2 of the G12A AO-CLK IDs, the CLKID_AO_CTS_OSCIN was moved
to the internal non-exported bindings, but this clock is necessary for
the second AO-CEC-B module since it embeds the 32768Hz dual-divider
clock generator unlike the AO-CEC-A module.

Export it back to the public bindings.

Fixes: be3d960b0a ("dt-bindings: clk: add G12A AO Clock and Reset Bindings")
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lkml.kernel.org/r/20190321092010.14382-1-narmstrong@baylibre.com
2019-04-01 10:45:11 +02:00
Jerome Brunet
e4c1e95fac dt-bindings: clock: axg-audio: unexpose controller inputs
Remove the bindings ID of the clock input of the controller. These
clocks are purely internal to the controller, exposing them was a
mistake. Actually, these should not even be in the provider and have
IDs to begin with.

Unexpose these IDs before:
 * someone starts using them (even if there no valid reason to do so)
 * the actual clocks are removed. The fact that they exist is just the
   result of an ugly hack. This will be resolved in CCF when we can
   reference DT directly in parent table.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Acked-by: Maxime Jourdan <mjourdan@baylibre.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20190213095835.17448-1-jbrunet@baylibre.com
2019-04-01 10:45:11 +02:00
Neil Armstrong
dc6276f576 clk: g12a-aoclk: re-export CLKID_AO_SAR_ADC_SEL clock id
When submitted v2 of the G12A AO-CLK IDs, the SAR_ADC_SEL ID was moved
to the internal non-exported bindings, but this clock is necessary and
mandatory for the SAR ADC bindings.

Export it back to the public bindings.

Fixes: be3d960b0a ("dt-bindings: clk: add G12A AO Clock and Reset Bindings")
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lkml.kernel.org/r/20190304105358.4987-1-narmstrong@baylibre.com
2019-03-19 21:10:21 +01:00
Martin Blumenstingl
c5f09e6bd8 clk: meson: meson8b: fix the naming of the APB clocks
Fix a typo in the APB clock names by renaming them from "abp" to "apb".
No functional changes.

Fixes: a7d19b05ce ("clk: meson: meson8b: add the CPU clock post divider clocks")
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lkml.kernel.org/r/20190210222603.6404-2-martin.blumenstingl@googlemail.com
2019-02-13 09:51:09 +01:00
Neil Armstrong
042f01bb7f clk: meson: Add G12A AO Clock + Reset Controller
Add the Amlogic G12A AO Clock and Reset controller driver handling
generation of Always-On clocks :
- AO Clocks and Reset for Always-On modules
- 32K Generation for USB and CEC
- SAR ADC controller clock

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lkml.kernel.org/r/20190212162859.20743-3-narmstrong@baylibre.com
2019-02-13 09:49:32 +01:00
Jerome Brunet
6682bd4d44 clk: meson: factorise meson64 peripheral clock controller drivers
The function used to probe the peripheral clock controller of the arm64
amlogic SoCs is mostly the same. We now have 3 of those controllers so
it is time to factorize things a bit.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20190201145345.6795-5-jbrunet@baylibre.com
2019-02-04 09:52:11 +01:00
Jian Hu
085a4ea93d clk: meson: g12a: add peripheral clock controller
Add the peripheral clock controller found in the g12a SoC family

Signed-off-by: Jian Hu <jian.hu@amlogic.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20190201145345.6795-4-jbrunet@baylibre.com
2019-02-04 09:52:11 +01:00
Jerome Brunet
8eed1db1ad clk: meson: pll: update driver for the g12a
The g12a use fractional parameter of 17 useful bits. At the moment, this
parameter in encoded using u16 value. Use this opportunity to switch all
the pll to parameter to unsigned int. This should save us some annoying
trouble shooting when and m and n field eventually grow as well.

This patch also introduce pll multiplier range. On the g12a, the hifi and
gp0 plls are able to lock as long as the following condition is met:
55 <= m/n <= 255.

The param table describing this would be huge which is a waste of memory.
Using ranges, we can save memory. Ranges also help find the best pll
parameter significantly faster since we don't have to try all the possible
settings.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
[jbrunet: fixed fix pll settings calculation with arm32]
Link: https://lkml.kernel.org/r/20190201145345.6795-2-jbrunet@baylibre.com
2019-02-04 09:51:37 +01:00
Jerome Brunet
889c2b7ec4 clk: meson: rework and clean drivers dependencies
Initially, the meson clock directory only hosted 2 controllers drivers,
for meson8 and gxbb. At the time, both used the same set of clock drivers
so managing the dependencies was not a big concern.

Since this ancient time, entropy did its job, controllers with different
requirement and specific clock drivers have been added. Unfortunately, we
did not do a great job at managing the dependencies between the
controllers and the different clock drivers. Some drivers, such as
clk-phase or vid-pll-div, are compiled even if they are useless on the
target (meson8). As we are adding new controllers, we need to be able to
pick a driver w/o pulling the whole thing.

The patch aims to clean things up by:
* providing a dedicated CONFIG_ for each clock drivers
* allowing clock drivers to be compiled as a modules, if possible
* stating explicitly which drivers are required by each controller.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20190201125841.26785-5-jbrunet@baylibre.com
2019-02-02 17:43:32 +01:00
Jerome Brunet
cb78ba7629 clk: meson: axg-audio does not require syscon
The axg audio clock controller uses regmap mmio, not syscon.

Fixes: 1cd5018175 ("clk: meson: axg: add the audio clock controller driver")
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20190201125841.26785-4-jbrunet@baylibre.com
2019-02-02 17:43:08 +01:00
Jerome Brunet
439a6bb5bf clk: meson: ao-clkc: claim clock controller input clocks from DT
Instead of relying on a fixed names for the differents input clocks
of the controller, get them through DT.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20190116175435.4990-4-jbrunet@baylibre.com
2019-01-18 10:51:39 +01:00
Jerome Brunet
6e73dac707 clk: meson: axg: claim clock controller input clock from DT
Instead of relying on a fixed name for the xtal clock, claim the
controller input clock trough DT.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20190116175435.4990-3-jbrunet@baylibre.com
2019-01-18 10:51:14 +01:00
Jerome Brunet
c0e6f5bf76 clk: meson: gxbb: claim clock controller input clock from DT
Instead of relying on a fixed name for the xtal clock, claim the
controller input clock trough DT.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20190116175435.4990-2-jbrunet@baylibre.com
2019-01-18 10:49:26 +01:00
Martin Blumenstingl
74e1f2521f clk: meson: meson8b: add the GPU clock tree
Add the GPU clock tree on Meson8, Meson8b and Meson8m2.

The GPU clock tree on Meson8b and Meson8m2 is almost identical to the
one one GXBB:
- there's a glitch-free mux at HHI_MALI_CLK_CNTL[31]
- there are two identical parents for this mux: mali_0 and mali_1, each
  with a gate, divider and mux
- the parents of mali_0_sel and mali_1_sel are identical to GXBB except
  there's no GP0_PLL on these 32-bit SoCs

Meson8 is different because it does not have the glitch-free mux.
Instead if only has the mali_0 clock tree. The parents of mali_0_sel are
identical to the ones on Meson8b and Meson8m2.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20181208171247.22238-4-martin.blumenstingl@googlemail.com
2019-01-07 15:35:13 +01:00
Martin Blumenstingl
cce433e6bc clk: meson: meson8b: use a separate clock table for Meson8
The Meson8 SoC is slightly different compared to Meson8b and Meson8m2
because it does not have the glitch-free Mali GPU clock mux. For Meson8b
and Meson8m2 there are currently no known differences.

Add a separate clk_hw_onecell_data table for Meson8 so these differences
can be implemented. For now meson8_hw_onecell_data is a clone of our
existing meson8b_hw_onecell_data.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20181208171247.22238-3-martin.blumenstingl@googlemail.com
2019-01-07 15:34:54 +01:00
Jerome Brunet
172e95346d clk: meson: axg-ao: add 32k generation subtree
Add the clock subtree generating the 32k clock in amlogic axg ao block.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20181221160239.26265-6-jbrunet@baylibre.com
2019-01-07 15:21:43 +01:00
Jerome Brunet
b249623fd1 clk: meson: gxbb-ao: replace cec-32k with the dual divider
Replace the cec-32k clock of gxbb-ao with the simpler dual divider
driver. The dual divider implements only the dividing part. All the
other bits are now exposed using simple elements, such as gates and
muxes

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20181221160239.26265-5-jbrunet@baylibre.com
2019-01-07 15:21:22 +01:00
Jerome Brunet
a8d552a638 clk: meson: add dual divider clock driver
Add the dual divider driver. This special divider make a weighted
average between 2 dividers to reach fractional divider values.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20181221160239.26265-4-jbrunet@baylibre.com
2019-01-07 15:21:01 +01:00
Jerome Brunet
8d9981efbc clk: meson: clean-up clock registration
Order, ids and size  between the table of regmap clocks and the onecell
data table could be different.

Set regmap pointer in all the regmap clocks before starting the
registration using the onecell data, to make sure we don't
get into an incoherent situation.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20181221160239.26265-3-jbrunet@baylibre.com
2019-01-07 15:20:41 +01:00
Stephen Boyd
9dc3204247 Merge branch 'clk-fixes' into clk-next
* clk-fixes:
  clk: qcom: qcs404: Fix gpll0_out_main parent
  clk: zynqmp: Off by one in zynqmp_is_valid_clock()
  clk: mmp: Off by one in mmp_clk_add()
  clk: mvebu: Off by one bugs in cp110_of_clk_get()
  arm64: dts: qcom: sdm845-mtp: Mark protected gcc clocks
  clk: zynqmp: handle fixed factor param query error
  clk: qcom: gcc: Fix board clock node name
  clk: meson: axg: mark fdiv2 and fdiv3 as critical
  clk: meson-gxbb: set fclk_div3 as CLK_IS_CRITICAL
  clk: fixed-factor: fix of_node_get-put imbalance
2018-12-14 13:42:08 -08:00
Stephen Boyd
e74581b79d Update for meson clocks targeted at v4.21, round 2:
- Fix GXL HDMI Pll fractional bits (from first round)
 - Add the Meson8/Meson8b video clocks
 - Add clk-input helper and use it for axg-audio clock driver
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Merge tag 'meson-clk-4.21-2' of https://github.com/BayLibre/clk-meson into clk-meson

Pull more meson clk driver updates from Neil Armstrong:

 - Fix GXL HDMI Pll fractional bits (from first round)
 - Add the Meson8/Meson8b video clocks
 - Add clk-input helper and use it for axg-audio clock driver

* tag 'meson-clk-4.21-2' of https://github.com/BayLibre/clk-meson:
  clk: meson: axg-audio: use the clk input helper function
  clk: meson: add clk-input helper function
  clk: meson: meson8b: add the read-only video clock trees
  clk: meson: meson8b: add the fractional divider for vid_pll_dco
  clk: meson: meson8b: fix the offset of vid_pll_dco's N value
  clk: meson: Fix GXL HDMI PLL fractional bits width
2018-12-13 01:05:44 -08:00
Jerome Brunet
f03566d0aa clk: meson: axg-audio: use the clk input helper function
Rework the axg audio clock controller to use the new clk-input helper
function.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
[narmstrong: fixed pclk input clock name to axg_audio_pclk]
Link: http://lkml.kernel.org/r/20181204165819.21541-3-jbrunet@baylibre.com
2018-12-11 16:07:03 +01:00
Jerome Brunet
e456e6a12b clk: meson: add clk-input helper function
Add the clock input helper function. Several amlogic clock controllers
will now be registering bypass clock input. Instead of copying this
code in every of them, let's make an helper function for it

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
[narmstrong: fixed up to apply on Makefile and clkc.h]
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20181204165819.21541-2-jbrunet@baylibre.com
2018-12-05 11:24:40 +01:00
Stephen Boyd
8913e8a73d clk: meson: Mark some things static
These are missing 'static' so sparse complains:

drivers/clk/meson/vid-pll-div.c:58:26: warning: symbol '_get_table_val' was not declared. Should it be static?
drivers/clk/meson/gxbb.c:1585:12: warning: symbol 'gxbb_vid_pll_parent_names' was not declared. Should it be static?
drivers/clk/meson/gxbb.c:1620:12: warning: symbol 'gxbb_vclk_parent_names' was not declared. Should it be static?
drivers/clk/meson/gxbb.c:1980:12: warning: symbol 'gxbb_cts_parent_names' was not declared. Should it be static?
drivers/clk/meson/gxbb.c:2036:12: warning: symbol 'gxbb_cts_hdmi_tx_parent_names' was not declared. Should it be static?

Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2018-12-03 13:52:56 -08:00
Martin Blumenstingl
6cb57c678b clk: meson: meson8b: add the read-only video clock trees
Add all clocks to give us the final video clocks within the Meson8,
Meson8b and Meson8m2 SoCs. The final video clocks are:
- cts_enct
- cts_encl
- cts_encp
- cts_enci
- cts_vdac0
- hdmi_tx_pixel
- hdmi_sys

Add multiple clocks in between which are needed to implement these
clocks:
- Opposed to GXBB there is no pre-multiplier for the PLL input. The
  assumption here is that the multiplier is required to achieve the HDMI
  2.0 clock rates (which are up to twice the rate of the HDMI 1.4
  rates).
- The main PLL is called "HDMI PLL" or "HPLL" in the datasheet. Rename
  our existing "vid_pll_dco" to "hdmi_pll_dco". The actual VID_PLL clock
  also exists further down the tree.
- Rename the existing "vid_pll" clock (which is the OD divider at
  HHI_VID_PLL_CNTL[17:16]) to "hdmi_pll_lvds_out" to match the naming
  from the datasheet.
- Add the second OD divider called "hdmi_pll_hdmi_out" at
  HHI_VID_PLL_CNTL[19:18].
- Add the "vid_pll_in_sel" which can choose between "hdmi_pll_dco" and
  another parent. However, the second parent is not use on Amlogic's
  3.10 kernel for HDMI or CVBS output so just leave a TODO in the code.
- Add the "vid_pll_in_en" which is located after "vid_pll_in_sel"
  according to the datasheet.
- Add "vid_pll_pre_div" which is used for divide-by-5 and divide-by-6 in
  Amlogic's 3.10 kernel sources.
- Add "vid_pll_post_div" which divides the output of "vid_pll_pre_div"
  further down. The Amlogic 3.10 kernel configures this as divide-by-2
  with "vid_pll_pre_div" being configured as divide-by-5 to achieve a
  total divider of 10.
- Add the real "vid_pll" clock which selects between "vid_pll_pre_div",
  "vid_pll_post_div" and a third "vid_pll_pre_div_mult7_div2" (which is
  "vid_pll_pre_div" divided by 3.5). The latter is not supported yet
  because it's not used in Amlogic's 3.10 kernel. The "vid_pll" clock
  rate can also be measured by clkmsr to check whether this
  implementation is correct.
- Add "vid_pll_final_div" which is a post-divider for "vid_pll" and it's
  used as input for "vclk" and "vclk2"
- Add the two symmetric "vclk" and "vclk" clock trees, each with a
  divide-by-1, divide-by-2, divide-by-4, divide-by-6 and divide-by-12
  clock and a divider for each clock.
- Add the "cts_enct", "cts_encp" and "hdmi_tx_pixel" clocks which each
  have their own gate and can select between any of the five "vclk"
  dividers.
- Add the "cts_encl" and "cts_vdac0" clocks which each have their own
  gate and can select between any of the five "vclk2" dividers.

The "hdmi_sys" clock is a different than these video clocks. It takes
"xtal" as input (there are three more but unknown parents). Add this
clock as well as it's used by the HDMI controller. Amlogic's 3.10 kernel
always configures this as "xtal divided by 1", so we can ignore the
other parents for now.

This was tested on Meson8b and Meson8m2 boards by comparing the common
clock framework output with the clock measurer output. The following
video modes were first set in u-boot (by running "video dev open $mode")
before booting Linux:
4K2K30HZ (only supported by Meson8m2, not tested on Meson8b):
- vid_pll: 297000000Hz
- cts_encp: 297000000Hz
- hdmi_tx_pixel: 297000000Hz
1080P:
- vid_pll: 148500000Hz
- cts_encp: 148500000Hz
- hdmi_tx_pixel: 148500000Hz
720P:
- vid_pll: 148500000Hz
- cts_encp: 148500000Hz
- hdmi_tx_pixel: 74250000Hz
480P:
- vid_pll: 216000000Hz
- cts_encp: 54000000Hz
- hdmi_tx_pixel: 27000000Hz

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20181202214220.7715-4-martin.blumenstingl@googlemail.com
2018-12-03 11:50:06 +01:00
Martin Blumenstingl
007f3da7d3 clk: meson: meson8b: add the fractional divider for vid_pll_dco
This "vid_pll_dco" (which should be named HDMI_PLL or - as the datasheet
calls it - HPLL) has a 12-bit wide fractional parameter at
HHI_VID_PLL_CNTL2[11:0]. Add this so we correctly calculate the rate of
this PLL when u-boot is configured for a video mode which uses this
fractional parameter.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20181202214220.7715-3-martin.blumenstingl@googlemail.com
2018-12-03 11:49:51 +01:00
Martin Blumenstingl
376d8c45bd clk: meson: meson8b: fix the offset of vid_pll_dco's N value
Unlike the other PLLs on Meson8b the N value "vid_pll_dco" (a better
name would be hdmi_pll_dco or - as the datasheet calls it - HPLL) is
located at HHI_VID_PLL_CNTL[14:10] instead of [13:9].
This results in an incorrect calculation of the rate of this PLL because
the value seen by the kernel is double the actual N (divider) value.
Update the offset of the N value to fix the calculation of the PLL rate.

Fixes: 28b9fcd016 ("clk: meson8b: Add support for Meson8b clocks")
Reported-by: Jianxin Pan <jianxin.pan@amlogic.com>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20181202214220.7715-2-martin.blumenstingl@googlemail.com
2018-12-03 11:49:13 +01:00
Neil Armstrong
21310c39ec clk: meson: Fix GXL HDMI PLL fractional bits width
The GXL Documentation specifies 12 bits for the Fractional bit field,
bit the last bits have a different purpose that we cannot handle right
now, so update the bitwidth to have correct fractional calculations.

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
[narmstrong: added comment on GXL HHI_HDMI_PLL_CNTL register shift]
Acked-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Link: https://lkml.kernel.org/r/20181121111922.1277-1-narmstrong@baylibre.com
2018-11-27 16:30:54 +01:00
Martin Blumenstingl
a7d19b05ce clk: meson: meson8b: add the CPU clock post divider clocks
There are four CPU clock post dividers:
- ABP
- PERIPH (used for the ARM global timer and ARM TWD timer)
- AXI
- L2 DRAM

Each of these clocks consists of two clocks:
- a mux to select between "cpu_clk" divided by 2, 3, 4, 5, 6, 7 or 8
- a "_clk_dis" gate. The public S805 datasheet states that this should
  be set to 1 to disable the clock, the default value is 0. There is
  also a hint that these are "just in case" bits which only exist in
  case the corresponding mux implementation does not allow glitch-free
  parent changes (the muxes are designed in a way that the clock can
  stay enabled when changing the mux). It's still good practise to
  describe this clock even if we're not supposed to modify it. Thus
  this uses the read-only gate ops.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20181122214017.25643-5-martin.blumenstingl@googlemail.com
2018-11-23 15:11:58 +01:00
Martin Blumenstingl
700ecf7f51 clk: meson: meson8b: rename cpu_div2/cpu_div3 to cpu_in_div2/cpu_in_div3
The "cpu_div2" and "cpu_div3" take "cpu_in" as input and divide that by
2 or 3. The clock controller can also generate various CPU clock
post-dividers (2, 3, 4, 5, 6, 7, 8) which are derived from "cpu_clk".
When adding support for these post-dividers our clock naming could be
misleading as we have "cpu_div2" as well as "cpu_clk_div2".
Rename the existing "cpu_in" dividers so the name of the divider's
parent is part of the divider clock's name.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20181122214017.25643-4-martin.blumenstingl@googlemail.com
2018-11-23 15:11:58 +01:00
Martin Blumenstingl
3cf94c94e8 clk: meson: clk-regmap: add read-only gate ops
Some of the gate clocks are described as "just in case" bits in the
datasheet. Examples are the ABP, PERIPH, AXI and L2 DRAM clocks on
Meson8b.
The datasheet suggests that these bits are not touched. The full
explanation is:
"Set to 1 to manually disable the [...] clock when changing the mux
selection. Typically this bit is set to 0 since the clock muxes can
switch without glitches.".

This adds new read-only ops for gate clocks so we can describe these
clocks in our clock controller drivers while ensuring that we can't
accidentally modify the registers.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20181122214017.25643-3-martin.blumenstingl@googlemail.com
2018-11-23 15:11:58 +01:00
Martin Blumenstingl
7fc1609b0c clk: meson: meson8b: allow changing the CPU clock tree
Currently all clocks in the CPU clock tree are marked as read-only
(using the corresponding _ro_ clk_ops). This was correct since changing
the clock tree could cause the system to lock up.
Switch all clocks to their corresponding clk_ops variant which is not
read-only to allow changing the CPU clock tree since the bug which
locked up the system is now fixed (by switching the CPU clock temporary
to run off XTAL while changing the CPU clock tree).

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20181115224048.13511-7-martin.blumenstingl@googlemail.com
2018-11-23 15:11:58 +01:00
Martin Blumenstingl
7dc7eeb8c0 clk: meson: meson8b: run from the XTAL when changing the CPU frequency
Changing the CPU clock requires changing various clocks including the
SYS PLL. The existing meson clk-pll and clk-regmap drivers can change
all of the relevant clocks already.
However, changing for exampe the SYS PLL is problematic because as long
as the CPU is running off a clock derived from SYS PLL changing the
latter results in a full system lockup.
Fix this system lockup by switching the CPU clock to run off the XTAL
while we are changing the any of the clocks in the CPU clock tree.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20181115224048.13511-6-martin.blumenstingl@googlemail.com
2018-11-23 15:11:58 +01:00
Martin Blumenstingl
e36c7e9898 clk: meson: meson8b: add support for more M/N values in sys_pll
The sys_pll on the EC-100 board is configured to 1584MHz at boot
(either by u-boot, firmware or chip defaults). This is achieved by using
M = 66, N = 1 (24MHz * 66 / 1).
At boot the CPU clock is running off sys_pll divided by 2 which results
in 792MHz. Thus M = 66 is considered to be a "safe" value for Meson8b.

To achieve 1608MHz (one of the CPU OPPs on Meson8 and Meson8m2) we need
M = 67, N = 1. I ran "stress --cpu 4" while infinitely cycling through
all available frequencies on my Meson8m2 board and could not spot any
issues with this setting (after ~12 hours of running this).

On Meson8, Meson8b and Meson8m2 we also want to be able to use 408MHz
and 816MHz CPU frequencies. These can be achieved by dividing sys_pll by
4 (for 408MHz) or 2 (for 816MHz). That means that sys_pll has to run at
1632MHz which can be generated using M = 68, N = 1.
Similarily we also want to be able to use 1008MHz as CPU frequency. This
means that sys_pll has to run either at 1008MHz or 2016MHz. The former
would result in an M value of 42, which is lower than the smallest value
used by the 3.10 GPL kernel sources from Amlogic (50 is the lower limit
there). Thus we need to run sys_pll at 2016MHz which can ge generated
using M = 84, N = 1.
I tested M = 68 and M = 84 on my Meson8b Odroid-C1 and my Meson8m2 board
by running "stress --cpu 4" while infinitely cycling thorugh all
available frequencies. I could not spot any issues after ~12 hours of
running this.

Amlogic's 3.10 GPL kernel sources have more M/N combinations. I did not
add them yet because M = 74 (to achieve close to 1800MHz on Meson8) and
M = 82 (to achieve close to 1992MHz on Meson8 as well) caused my
Meson8m2 board to hang randomly. It's not clear why this is (for example
because the board's voltage regulator design is bad, some missing bits
for these values in our clk-pll driver, etc.). Thus the following M
values from the Amlogic 3.10 GPL kernel sources are skipped as of now:
69, 70, 71, 72, 73, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20181115224048.13511-5-martin.blumenstingl@googlemail.com
2018-11-23 15:11:58 +01:00
Martin Blumenstingl
0dad1ec65b clk: meson: meson8b: mark the CPU clock as CLK_IS_CRITICAL
We don't want the common clock framework to disable the "cpu_clk" if
it's not used by any device. The cpufreq-dt driver does not enable the
CPU clocks. However, even if it would we would still want the CPU clock
to be enabled at all times because the CPU clock is also required even
if we disable CPU frequency scaling on a specific board.

The reason why we want the CPU clock to be enabled is a clock further up
in the tree:
Since commit 6f888e7bc7bd58 ("clk: meson: clk-pll: add enable bit") the
sys_pll can be disabled. However, since the CPU clock is derived from
sys_pll we don't want sys_pll to get disabled. The common clock
framework takes care of that for us by enabling all parent clocks of our
CPU clock when we mark the CPU clock with CLK_IS_CRITICAL.

Until now this is not a problem yet because all clocks in the CPU
clock's tree (including sys_pll) are read-only. However, once we allow
modifications to the clocks in that tree we will need this.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20181115224048.13511-4-martin.blumenstingl@googlemail.com
2018-11-23 15:11:57 +01:00
Martin Blumenstingl
a5ac1ead32 clk: meson: meson8b: do not use cpu_div3 for cpu_scale_out_sel
The cpu_div3 clock (cpu_in divided by 3) generates a signal with a duty
cycle of 33%. The CPU clock however requires a clock signal with a duty
cycle of 50% to run stable.
cpu_div3 was observed to be problematic when cycling through all
available CPU frequencies (with additional patches on top of this one)
while running "stress --cpu 4" in the background. This caused sporadic
hangs where the whole system would fully lock up.

Amlogic's 3.10 kernel code also does not use the cpu_div3 clock either
when changing the CPU clock.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20181115224048.13511-3-martin.blumenstingl@googlemail.com
2018-11-23 15:11:57 +01:00
Martin Blumenstingl
d6e81845b7 clk: meson: clk-pll: check if the clock is already enabled
Since commit 6f888e7bc7bd58 ("clk: meson: clk-pll: add enable bit") our
PLLs also support the "enable" bit. Currently meson_clk_pll_enable
unconditionally resets the PLL, enables it, takes it out of reset and
waits until it is locked.

This works fine for our current clock trees. However, there will be a
problem once we allow modifications to sys_pll on Meson8, Meson8b and
Meson8m2 (which will be required for CPU frequency scaling):
the CPU clock is derived from the sys_pll clock. Once clk_enable is
called on the CPU clock this will be propagated by the common clock
framework up until the sys_pll clock. If we reset the PLL
unconditionally in meson_clk_pll_enable the CPU will be stopped (on
Meson8, Meson8b and Meson8m2).
To prevent this we simply check if the PLL is already enabled and do
reset the PLL if it's already enabled and locked.

Now that we have a utility function to check whether the PLL is enabled
we can also pass that to our clk_ops to let the common clock framework
know about the status of the hardware clock.
For now this is of limited use since the only common clock framework's
internal "disabled unused clocks" mechanism checks for this. Everything
else still uses the ref-counting (internal to the common clock
framework) when clk_enable is called.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20181115224048.13511-2-martin.blumenstingl@googlemail.com
2018-11-23 15:11:57 +01:00
Martin Blumenstingl
a8662eadd1 clk: meson: meson8b: fix the width of the cpu_scale_div clock
According to the public S805 datasheet HHI_SYS_CPU_CLK_CNTL1[29:20] is
the register for the CPU scale_div clock. This matches the code in
Amlogic's 3.10 GPL kernel sources:
N = (aml_read_reg32(P_HHI_SYS_CPU_CLK_CNTL1) >> 20) & 0x3FF;

This means that the divider register is 10 bit wide instead of 9 bits.
So far this is not a problem since all u-boot versions I have seen are
not using the cpu_scale_div clock at all (instead they are configuring
the CPU clock to run off cpu_in_sel directly).

The fixes tag points to the latest rework of the CPU clocks. However,
even before the rework it was wrong. Commit 7a29a86943 ("clk: meson:
Add support for Meson clock controller") defines MESON_N_WIDTH as 9 (in
drivers/clk/meson/clk-cpu.c). But since the old clk-cpu implementation
this only carries the fixes tag for the CPU clock rewordk.

Fixes: 251b6fd38b ("clk: meson: rework meson8b cpu clock")
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20180927085921.24627-3-martin.blumenstingl@googlemail.com
2018-11-23 15:11:57 +01:00
Martin Blumenstingl
ad9b2b8e53 clk: meson: meson8b: fix incorrect divider mapping in cpu_scale_table
The public S805 datasheet only mentions that
HHI_SYS_CPU_CLK_CNTL1[20:29] contains a divider called "cpu_scale_div".
Unfortunately it does not mention how to use the register contents.

The Amlogic 3.10 GPL kernel sources are using the following code to
calculate the CPU clock based on that register (taken from
arch/arm/mach-meson8/clock.c in the 3.10 Amlogic kernel, shortened to
make it easier to read):
N = (aml_read_reg32(P_HHI_SYS_CPU_CLK_CNTL1) >> 20) & 0x3FF;
if (sel == 3) /* use cpu_scale_div */
  div = 2 * N;
else
  div = ... /* not relevant for this example */
cpu_clk = parent_clk / div;

This suggests that the formula is: parent_rate / 2 * register_value
However, running perf (which can measure the CPU clock rate thanks to
the ARM PMU) shows that this formula is not correct.
This can be reproduced with the following steps:
1. boot into u-boot
2. let the CPU clock run off the XTAL clock:
   mw.l 0xC110419C 0x30 1
3. set the cpu_scale_div register:
   to value 0x1: mw.l 0xC110415C 0x801016A2 1
   to value 0x2: mw.l 0xC110415C 0x802016A2 1
   to value 0x5: mw.l 0xC110415C 0x805016A2 1
4. let the CPU clock run off cpu_scale_div:
   mw.l 0xC110419C 0xbd 1
5. boot Linux
6. run: perf stat -aB stress --cpu 4 --timeout 10
7. check the "cycles" value

I get the following results depending on the cpu_scale_div value:
- (cpu_in_sel - this is the input clock for cpu_scale_div - runs at
   1.2GHz)
- 0x1 = 300MHz
- 0x2 = 200MHz
- 0x5 = 100MHz

This means that the actual formula to calculate the output of the
cpu_scale_div clock is: parent_rate / 2 * (register value + 1).

The register value 0x0 is reserved. When letting the CPU clock run off
the cpu_scale_div while the value is 0x0 the whole board hangs (even in
u-boot).

I also verified this with the TWD timer: when adding this to the .dts
without specifying it's clock it will auto-detect the PERIPH (which is
the input clock of the TWD) clock rate (and the result is shown in the
kernel log). On Meson8, Meson8b and Meson8m2 the PERIPH clock is CPUCLK
divided by 4. This also matched for all three test-cases from above (in
all cases the TWD timer clock rate was approx. one fourth of the CPU
clock rate).

A small note regarding the "fixes" tag: the original issue seems to
exist virtually since forever. Even commit 28b9fcd016 ("clk:
meson8b: Add support for Meson8b clocks") seems to handle this wrong. I
still decided to use commit 251b6fd38b ("clk: meson: rework meson8b
cpu clock") because this is the first commit which gets the CPU hiearchy
correct and thus it's the first commit where the cpu_scale_div register
is used correctly (apart from the bug in the cpu_scale_table).

Fixes: 251b6fd38b ("clk: meson: rework meson8b cpu clock")
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20180927085921.24627-2-martin.blumenstingl@googlemail.com
2018-11-23 15:11:57 +01:00
Martin Blumenstingl
bb6eddd1d2 clk: meson: meson8b: use the HHI syscon if available
The clock controller is located in a register range (called "HHI") which
contains more than just registers for the clock controller. Known
consumers of the HHI register range are:
- the clock controller
- a reset controller
- temperature sensor calibration coefficient (TSC) (only on Meson8b and
  Meson8m2)
- HDMI controller

The main reason for using a syscon is the "temperature sensor
calibration coefficient" which has to be set for the built-in temperature
sensor to work correctly. Four TSC bits are located in the SAR ADC's
register space. However on Meson8b and Meson8m2 there is a fifth TSC bit
which is unfortunately located in the HHI register space. To be more
precise, bit 9 of the HHI_DPLL_TOP_0 register (which sits right between
the HHI_SYS_PLL and HHI_VID_PLL registers).

Get the regmap from the parent (HHI syscon) node to support all
functionality of the HHI register range. Backwards compatibility with
old .dtbs is ensured by falling back to parsing the registers just like
before this change.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20181028120859.5735-3-martin.blumenstingl@googlemail.com
2018-11-23 15:11:56 +01:00