This series adds support for the clock and reset controller in the Nuvoton
WPCM450 SoC. This means that the clock rates for peripherals will be calculated
automatically based on the clock tree as it was preconfigured by the bootloader.
The 24 MHz dummy clock, that is currently in the devicetree, is no longer needed.
Somewhat unfortunately, this also means that there is a breaking change once
the devicetree starts relying on the clock driver, but I find it acceptable in
this case, because WPCM450 is still at a somewhat early stage.
Upstreaming plan (although other suggestions are welcome):
Once reviewed,
- The ARM/dts changes should go through Joel Stanley's bmc tree
- The clocksource/timer changes should probably go via Daniel Lezcano and TIP
- The watchdog patch should go via the watchdog tree
- The clock controller bindings and driver should go through the clk tree
- It might make sense to delay the final ARM/dts patch ("ARM: dts: wpcm450:
Switch clocks to clock controller") until next cycle to make sure it is
merged after the clock driver.
New in version 2:
- various small improvements
v1:
- https://lore.kernel.org/lkml/[email protected]/
Jonathan Neuschäfer (7):
dt-bindings: timer: nuvoton,npcm7xx-timer: Allow specifying all clocks
clocksource: timer-npcm7xx: Enable timer 1 clock before use
watchdog: npcm: Enable clock if provided
dt-bindings: clock: Add Nuvoton WPCM450 clock/reset controller
ARM: dts: wpcm450: Add clock controller node
clk: wpcm450: Add Nuvoton WPCM450 clock/reset controller driver
ARM: dts: wpcm450: Switch clocks to clock controller
.../bindings/clock/nuvoton,wpcm450-clk.yaml | 66 +++
.../bindings/timer/nuvoton,npcm7xx-timer.yaml | 8 +-
arch/arm/boot/dts/nuvoton-wpcm450.dtsi | 29 +-
drivers/clk/Makefile | 1 +
drivers/clk/clk-wpcm450.c | 378 ++++++++++++++++++
drivers/clocksource/timer-npcm7xx.c | 10 +
drivers/reset/Kconfig | 2 +-
drivers/watchdog/npcm_wdt.c | 12 +
.../dt-bindings/clock/nuvoton,wpcm450-clk.h | 67 ++++
9 files changed, 564 insertions(+), 9 deletions(-)
create mode 100644 Documentation/devicetree/bindings/clock/nuvoton,wpcm450-clk.yaml
create mode 100644 drivers/clk/clk-wpcm450.c
create mode 100644 include/dt-bindings/clock/nuvoton,wpcm450-clk.h
--
2.35.1
This change is incompatible with older kernels because it requires the
clock controller driver, but I think that's acceptable because WPCM450
support is generally still in an early phase.
Signed-off-by: Jonathan Neuschäfer <[email protected]>
---
v2:
- no changes
---
arch/arm/boot/dts/nuvoton-wpcm450.dtsi | 20 +++++++++-----------
1 file changed, 9 insertions(+), 11 deletions(-)
diff --git a/arch/arm/boot/dts/nuvoton-wpcm450.dtsi b/arch/arm/boot/dts/nuvoton-wpcm450.dtsi
index 62d70fda7b520..f868bd7db009a 100644
--- a/arch/arm/boot/dts/nuvoton-wpcm450.dtsi
+++ b/arch/arm/boot/dts/nuvoton-wpcm450.dtsi
@@ -2,6 +2,7 @@
// Copyright 2021 Jonathan Neuschäfer
#include <dt-bindings/interrupt-controller/irq.h>
+#include <dt-bindings/clock/nuvoton,wpcm450-clk.h>
/ {
compatible = "nuvoton,wpcm450";
@@ -32,13 +33,6 @@ cpu@0 {
};
};
- clk24m: clock-24mhz {
- /* 24 MHz dummy clock */
- compatible = "fixed-clock";
- clock-frequency = <24000000>;
- #clock-cells = <0>;
- };
-
refclk: clock-48mhz {
/* 48 MHz reference oscillator */
compatible = "fixed-clock";
@@ -73,7 +67,7 @@ serial0: serial@b8000000 {
reg = <0xb8000000 0x20>;
reg-shift = <2>;
interrupts = <7 IRQ_TYPE_LEVEL_HIGH>;
- clocks = <&clk24m>;
+ clocks = <&clk WPCM450_CLK_UART0>;
pinctrl-names = "default";
pinctrl-0 = <&bsp_pins>;
status = "disabled";
@@ -84,7 +78,7 @@ serial1: serial@b8000100 {
reg = <0xb8000100 0x20>;
reg-shift = <2>;
interrupts = <8 IRQ_TYPE_LEVEL_HIGH>;
- clocks = <&clk24m>;
+ clocks = <&clk WPCM450_CLK_UART1>;
status = "disabled";
};
@@ -92,14 +86,18 @@ timer0: timer@b8001000 {
compatible = "nuvoton,wpcm450-timer";
interrupts = <12 IRQ_TYPE_LEVEL_HIGH>;
reg = <0xb8001000 0x1c>;
- clocks = <&clk24m>;
+ clocks = <&clk WPCM450_CLK_TIMER0>,
+ <&clk WPCM450_CLK_TIMER1>,
+ <&clk WPCM450_CLK_TIMER2>,
+ <&clk WPCM450_CLK_TIMER3>,
+ <&clk WPCM450_CLK_TIMER4>;
};
watchdog0: watchdog@b800101c {
compatible = "nuvoton,wpcm450-wdt";
interrupts = <1 IRQ_TYPE_LEVEL_HIGH>;
reg = <0xb800101c 0x4>;
- clocks = <&clk24m>;
+ clocks = <&clk WPCM450_CLK_WDT>;
};
aic: interrupt-controller@b8002000 {
--
2.35.1
The timer module contains multiple timers. In the WPCM450 SoC, each timer
runs off a clock can be gated individually. To model this correctly, the
timer node in the devicetree needs to take multiple clock inputs.
Signed-off-by: Jonathan Neuschäfer <[email protected]>
---
v2:
- no changes
---
.../devicetree/bindings/timer/nuvoton,npcm7xx-timer.yaml | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/Documentation/devicetree/bindings/timer/nuvoton,npcm7xx-timer.yaml b/Documentation/devicetree/bindings/timer/nuvoton,npcm7xx-timer.yaml
index 0cbc26a721514..023c999113c38 100644
--- a/Documentation/devicetree/bindings/timer/nuvoton,npcm7xx-timer.yaml
+++ b/Documentation/devicetree/bindings/timer/nuvoton,npcm7xx-timer.yaml
@@ -23,7 +23,13 @@ properties:
- description: The timer interrupt of timer 0
clocks:
- maxItems: 1
+ items:
+ - description: The reference clock for timer 0
+ - description: The reference clock for timer 1
+ - description: The reference clock for timer 2
+ - description: The reference clock for timer 3
+ - description: The reference clock for timer 4
+ minItems: 1
required:
- compatible
--
2.35.1
On Fri, 29 Apr 2022 19:20:24 +0200, Jonathan Neusch?fer wrote:
> The timer module contains multiple timers. In the WPCM450 SoC, each timer
> runs off a clock can be gated individually. To model this correctly, the
> timer node in the devicetree needs to take multiple clock inputs.
>
> Signed-off-by: Jonathan Neusch?fer <[email protected]>
> ---
>
> v2:
> - no changes
> ---
> .../devicetree/bindings/timer/nuvoton,npcm7xx-timer.yaml | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
Reviewed-by: Rob Herring <[email protected]>