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
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
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
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
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
* 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
- 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
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
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
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>
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
Add the clocks entries used in the video clock path, the clock path
is doubled to permit having different synchronized clocks for different
parts of the video pipeline.
All dividers are flagged with CLK_GET_RATE_NOCACHE, and all gates are flagged
with CLK_IGNORE_UNUSED since they are currently directly handled by the
Meson DRM Driver.
Once the DRM Driver is fully migrated to using the Common Clock Framework
to handle the video clock tree, the CLK_GET_RATE_NOCACHE and CLK_IGNORE_UNUSED
will be dropped.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
Link: http://lkml.kernel.org/r/1541516257-16157-5-git-send-email-narmstrong@baylibre.com
In an attempt to better describe the HDMI PLL, a single DCO clock was
left for GXBB and GXL, but the GXL DCO does not have a pre-multiplier.
This patch adds back a GXL specific HDMI PLL DCO with xtal as parent.
Fixes: 87173557d2 ("clk: meson: clk-pll: remove od parameters")
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
Link: http://lkml.kernel.org/r/1541516257-16157-3-git-send-email-narmstrong@baylibre.com
Add support the VID_PLL fully programmable divider used right after the
HDMI PLL clock source. It is used to achieve complex fractional division
with a programmble bitfield.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
Link: http://lkml.kernel.org/r/1541516257-16157-2-git-send-email-narmstrong@baylibre.com
Similar to gxbb and gxl platforms, axg SCPI Cortex-M co-processor
uses the fdiv2 and fdiv3 to, among other things, provide the cpu
clock.
Until clock hand-off mechanism makes its way to CCF and the generic
SCPI claims platform specific clocks, these clocks must be marked as
critical to make sure they are never disabled when needed by the
co-processor.
Fixes: 05f814402d ("clk: meson: add fdiv clock gates")
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
On the Khadas VIM2 (GXM) and LePotato (GXL) board there are problems
with reboot; e.g. a ~60 second delay between issuing reboot and the
board power cycling (and in some OS configurations reboot will fail
and require manual power cycling).
Similar to 'commit c987ac6f1f ("clk:
meson-gxbb: set fclk_div2 as CLK_IS_CRITICAL")' the SCPI Cortex-M4
Co-Processor seems to depend on FCLK_DIV3 being operational.
Until commit 05f814402d ("clk:
meson: add fdiv clock gates"), this clock was modeled and left on by
the bootloader.
We don't have precise documentation about the SCPI Co-Processor and
its clock requirement so we are learning things the hard way.
Marking this clock as critical solves the problem but it should not
be viewed as final solution. Ideally, the SCPI driver should claim
these clocks. We also depends on some clock hand-off mechanism
making its way to CCF, to make sure the clock stays on between its
registration and the SCPI driver probe.
Fixes: 05f814402d ("clk: meson: add fdiv clock gates")
Signed-off-by: Christian Hewitt <christianshewitt@gmail.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
For now the reset controller was using raw register access because the
early init did not initialize the regmap. However, now that clocks are
initialized early we can simply use the regmap also for the reset
controller.
No functional changes.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Until now only the reset controller (part of the clock controller
register space) was registered early in the boot process, while the
clock controller itself was registered later on.
However, some parts of the SoC are initialized early in the boot process,
such as the SRAM and the TWD timer. The bootloader already enables these
clocks so we didn't see any issues so far.
Register the clock controller early so other drivers (such as the SRAM
and TWD timer) can use the clocks early in the boot process.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
We found the PCIe driver doesn't really work with
the mpll3 clock which is actually reserved for debug,
So drop it from the mux list.
Fixes: 33b89db68236 ("clk: meson-axg: add clocks required by pcie driver")
Tested-by: Jianxin Qin <jianxin.qin@amlogic.com>
Signed-off-by: Yixun Lan <yixun.lan@amlogic.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Some of the master clocks provided by the axg audio clock controller are
system clock (spdifin and pdm sysclk). They are used to clock an internal
DSP of the related devices. Having them constantly rounded down instead
of closest is preferable.
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Putting hard-coded rates inside the parameter tables assumes that
the parent is known and will never change. That's a big assumption
we should not make.
We have everything we need to recalculate the output rate using
the parent rate and the rest of the parameters. Let's do so and
drop the rates from the tables.
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Remove od parameters from pll clocks and add post dividers clocks
instead. Some clock, especially the one which feature several ods,
may provide output between those ods. Also, some drivers, such
as the hdmi driver, may require a more detailed control of the
clock dividers, compared to what CCF would perform automatically.
One added benefit of removing ods is that it also greatly reduce the
size of the rate parameter tables.
In the future, we could possibly take the predivider 'n' out of this
driver as well. To do so, we will need to understand the constraints
for the PLL to lock and whether or not it depends on the input clock
rate.
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
CLK_GET_RATE_NOCACHE should only be necessary when the registers
controlling the rate of clock may change outside of CCF. On Amlogic,
it should only be the case for the hdmi pll which is directly controlled
by the display driver (WIP to fix this).
The other plls should not require this flag.
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Add the enable the bit of the pll clocks.
These pll clocks may be disabled but we can't model this as an external
gate since the pll needs to lock when enabled.
Adding this bit allows to drop the poke of the first register of PLL.
This will be useful to model the different components of the pll using
generic clocks elements
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
GEN_CLK is able to route several internal clocks to one of the SoC
pads. In the future, even more clocks could be made accessible using
cts_msr_clk - the clock measure block.
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Adding clocks for the pcie driver. Due to the ASIC design,
the pcie controller re-use part of the mipi clock logic,
so the mipi clock is also added.
Tested-by: Jianxin Qin <jianxin.qin@amlogic.com>
Signed-off-by: Yixun Lan <yixun.lan@amlogic.com>
[amended to remove unnecessary locales]
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
clk-audio-divider is no longer used, we can remove it.
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
It is actually a lot easier to setup the PLL with carefully chosen rates
than relying on CCF clock propagation for this audio use case.
This way, we can make sure we will always be able to provide the common
audio clock rates, while having the PLL in the optimal operating range.
For this, we stop the rate propagation at the mux picking the
PLL and let it round to the closest matching PLL.
Doing so, we can use the generic divider for the i2s clock.
clk-audio-divider is no longer required. It was a (poor) attempt
to use CCF rate propagation while making sure the PLL rate would
be high enough to work with audio use cases.
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
The axg audio clock controller is the clock generation unit for the
amlogic audio subsystem of A113 based SoCs. It may be clocked by 8
different plls provided by the primary clock controller and also by
10 slave bit clocks and 10 slave sample clocks which may be provided
by external components, such as audio codecs, through the SoC pads.
It contains several muxes, dividers and gates which are fed into the
the different devices of the audio subsystem.
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Add a driver to control the clock divider found in the sample clock
generator of the axg audio clock controller.
The sclk divider accumulates specific features which make the generic
divider unsuitable to control it:
- zero based divider (div = val + 1), but zero value gates the clock,
so minimum divider value is 2.
- lrclk variant may adjust the duty cycle depending the divider value
and the 'hi' value.
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Add a driver to control the output of the sample clock generator found
in the axg audio clock controller.
The goal of this driver is to coherently control the phase provided to
the different element using the sample clock generator. This simplify
the usage of the sample clock generator a lot, without comprising the
ability of the SoC.
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Add a driver based meson clk-regmap to control clock phase on
amlogic SoCs
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Clean the dependencies in meson clock Kconfig.
CLK_AMLOGIC should actually select CLK_REGMAP_MESON which it uses. Also,
each platform should select CLK_AMLOGIC, so everything is properly turned
on when the platform Kconfig enable each configuration flag
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
