* [PATCH v4 0/6] Nuvoton WPCM450 clock and reset driver
@ 2022-06-10 7:21 Jonathan Neuschäfer
2022-06-10 7:21 ` [PATCH v4 1/6] dt-bindings: timer: nuvoton,npcm7xx-timer: Allow specifying all clocks Jonathan Neuschäfer
` (5 more replies)
0 siblings, 6 replies; 8+ messages in thread
From: Jonathan Neuschäfer @ 2022-06-10 7:21 UTC (permalink / raw)
To: linux-clk, openbmc
Cc: linux-kernel, linux-watchdog, devicetree,
Jonathan Neuschäfer, Michael Turquette, Stephen Boyd,
Rob Herring, Krzysztof Kozlowski, Avi Fishman, Tomer Maimon,
Tali Perry, Patrick Venture, Nancy Yuen, Benjamin Fair,
Daniel Lezcano, Thomas Gleixner, Philipp Zabel, Wim Van Sebroeck,
Guenter Roeck
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.
v4:
- Leave WDT clock running during after restart handler
- Fix reset controller initialization
- Dropped patch 2/7 (clocksource: timer-npcm7xx: Enable timer 1 clock before use),
as it was applied by Daniel Lezcano
v3:
- https://lore.kernel.org/lkml/20220508194333.2170161-1-j.neuschaefer@gmx.net/
- Changed "refclk" string to "ref"
- Fixed some dead code in the driver
- Added clk_prepare_enable call to the watchdog restart handler
- Added a few review tags
v2:
- https://lore.kernel.org/lkml/20220429172030.398011-1-j.neuschaefer@gmx.net/
- various small improvements
v1:
- https://lore.kernel.org/lkml/20220422183012.444674-1-j.neuschaefer@gmx.net/
Jonathan Neuschäfer (6):
dt-bindings: timer: nuvoton,npcm7xx-timer: Allow specifying all clocks
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 | 364 ++++++++++++++++++
drivers/reset/Kconfig | 2 +-
drivers/watchdog/npcm_wdt.c | 16 +
.../dt-bindings/clock/nuvoton,wpcm450-clk.h | 67 ++++
8 files changed, 544 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
^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH v4 1/6] dt-bindings: timer: nuvoton,npcm7xx-timer: Allow specifying all clocks
2022-06-10 7:21 [PATCH v4 0/6] Nuvoton WPCM450 clock and reset driver Jonathan Neuschäfer
@ 2022-06-10 7:21 ` Jonathan Neuschäfer
2022-06-10 7:21 ` [PATCH v4 2/6] watchdog: npcm: Enable clock if provided Jonathan Neuschäfer
` (4 subsequent siblings)
5 siblings, 0 replies; 8+ messages in thread
From: Jonathan Neuschäfer @ 2022-06-10 7:21 UTC (permalink / raw)
To: linux-clk, openbmc
Cc: linux-kernel, linux-watchdog, devicetree,
Jonathan Neuschäfer, Michael Turquette, Stephen Boyd,
Rob Herring, Krzysztof Kozlowski, Avi Fishman, Tomer Maimon,
Tali Perry, Patrick Venture, Nancy Yuen, Benjamin Fair,
Daniel Lezcano, Thomas Gleixner, Philipp Zabel, Wim Van Sebroeck,
Guenter Roeck, Rob Herring, Krzysztof Kozlowski
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 <j.neuschaefer@gmx.net>
Reviewed-by: Rob Herring <robh@kernel.org>
---
v4:
- no changes
v3:
- Add R-b tag
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
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH v4 2/6] watchdog: npcm: Enable clock if provided
2022-06-10 7:21 [PATCH v4 0/6] Nuvoton WPCM450 clock and reset driver Jonathan Neuschäfer
2022-06-10 7:21 ` [PATCH v4 1/6] dt-bindings: timer: nuvoton,npcm7xx-timer: Allow specifying all clocks Jonathan Neuschäfer
@ 2022-06-10 7:21 ` Jonathan Neuschäfer
2022-09-25 17:00 ` Guenter Roeck
2022-06-10 7:21 ` [PATCH v4 3/6] dt-bindings: clock: Add Nuvoton WPCM450 clock/reset controller Jonathan Neuschäfer
` (3 subsequent siblings)
5 siblings, 1 reply; 8+ messages in thread
From: Jonathan Neuschäfer @ 2022-06-10 7:21 UTC (permalink / raw)
To: linux-clk, openbmc
Cc: linux-kernel, linux-watchdog, devicetree,
Jonathan Neuschäfer, Michael Turquette, Stephen Boyd,
Rob Herring, Krzysztof Kozlowski, Avi Fishman, Tomer Maimon,
Tali Perry, Patrick Venture, Nancy Yuen, Benjamin Fair,
Daniel Lezcano, Thomas Gleixner, Philipp Zabel, Wim Van Sebroeck,
Guenter Roeck
On the Nuvoton WPCM450 SoC, with its upcoming clock driver, peripheral
clocks are individually gated and ungated. Therefore, the watchdog
driver must be able to ungate the watchdog clock.
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
---
v4:
- Don't disable clock in npcm_wdt_restart function
v3:
- https://lore.kernel.org/lkml/20220508194333.2170161-4-j.neuschaefer@gmx.net/
- Add enable/disable calls to npcm_wdt_restart handler
- Not applied due to the above change: Acked-by: Guenter Roeck <linux@roeck-us.net>
v2:
- https://lore.kernel.org/lkml/20220429172030.398011-4-j.neuschaefer@gmx.net/
- Add clk_disable_unprepare call, suggested by Guenter Roeck
v1:
- https://lore.kernel.org/lkml/20220422183012.444674-4-j.neuschaefer@gmx.net/
---
drivers/watchdog/npcm_wdt.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/drivers/watchdog/npcm_wdt.c b/drivers/watchdog/npcm_wdt.c
index 28a24caa2627c..a5dd1c2301374 100644
--- a/drivers/watchdog/npcm_wdt.c
+++ b/drivers/watchdog/npcm_wdt.c
@@ -3,6 +3,7 @@
// Copyright (c) 2018 IBM Corp.
#include <linux/bitops.h>
+#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
@@ -43,6 +44,7 @@
struct npcm_wdt {
struct watchdog_device wdd;
void __iomem *reg;
+ struct clk *clk;
};
static inline struct npcm_wdt *to_npcm_wdt(struct watchdog_device *wdd)
@@ -66,6 +68,9 @@ static int npcm_wdt_start(struct watchdog_device *wdd)
struct npcm_wdt *wdt = to_npcm_wdt(wdd);
u32 val;
+ if (wdt->clk)
+ clk_prepare_enable(wdt->clk);
+
if (wdd->timeout < 2)
val = 0x800;
else if (wdd->timeout < 3)
@@ -100,6 +105,9 @@ static int npcm_wdt_stop(struct watchdog_device *wdd)
writel(0, wdt->reg);
+ if (wdt->clk)
+ clk_disable_unprepare(wdt->clk);
+
return 0;
}
@@ -147,6 +155,10 @@ static int npcm_wdt_restart(struct watchdog_device *wdd,
{
struct npcm_wdt *wdt = to_npcm_wdt(wdd);
+ /* For reset, we start the WDT clock and leave it running. */
+ if (wdt->clk)
+ clk_prepare_enable(wdt->clk);
+
writel(NPCM_WTR | NPCM_WTRE | NPCM_WTE, wdt->reg);
udelay(1000);
@@ -191,6 +203,10 @@ static int npcm_wdt_probe(struct platform_device *pdev)
if (IS_ERR(wdt->reg))
return PTR_ERR(wdt->reg);
+ wdt->clk = devm_clk_get_optional(&pdev->dev, NULL);
+ if (IS_ERR(wdt->clk))
+ return PTR_ERR(wdt->clk);
+
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return irq;
--
2.35.1
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH v4 3/6] dt-bindings: clock: Add Nuvoton WPCM450 clock/reset controller
2022-06-10 7:21 [PATCH v4 0/6] Nuvoton WPCM450 clock and reset driver Jonathan Neuschäfer
2022-06-10 7:21 ` [PATCH v4 1/6] dt-bindings: timer: nuvoton,npcm7xx-timer: Allow specifying all clocks Jonathan Neuschäfer
2022-06-10 7:21 ` [PATCH v4 2/6] watchdog: npcm: Enable clock if provided Jonathan Neuschäfer
@ 2022-06-10 7:21 ` Jonathan Neuschäfer
2022-06-10 7:21 ` [PATCH v4 4/6] ARM: dts: wpcm450: Add clock controller node Jonathan Neuschäfer
` (2 subsequent siblings)
5 siblings, 0 replies; 8+ messages in thread
From: Jonathan Neuschäfer @ 2022-06-10 7:21 UTC (permalink / raw)
To: linux-clk, openbmc
Cc: linux-kernel, linux-watchdog, devicetree,
Jonathan Neuschäfer, Michael Turquette, Stephen Boyd,
Rob Herring, Krzysztof Kozlowski, Avi Fishman, Tomer Maimon,
Tali Perry, Patrick Venture, Nancy Yuen, Benjamin Fair,
Daniel Lezcano, Thomas Gleixner, Philipp Zabel, Wim Van Sebroeck,
Guenter Roeck, Krzysztof Kozlowski, Krzysztof Kozlowski
The Nuvoton WPCM450 SoC has a combined clock and reset controller.
Add a devicetree binding for it, as well as definitions for the bit
numbers used by it.
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
---
v4:
- Add R-b tag
v3:
- Change clock-output-names and clock-names from "refclk" to "ref", suggested
by Krzysztof Kozlowski
v2:
- https://lore.kernel.org/lkml/20220429172030.398011-5-j.neuschaefer@gmx.net/
- Various improvements, suggested by Krzysztof Kozlowski
v1:
- https://lore.kernel.org/lkml/20220422183012.444674-5-j.neuschaefer@gmx.net/
---
.../bindings/clock/nuvoton,wpcm450-clk.yaml | 66 ++++++++++++++++++
.../dt-bindings/clock/nuvoton,wpcm450-clk.h | 67 +++++++++++++++++++
2 files changed, 133 insertions(+)
create mode 100644 Documentation/devicetree/bindings/clock/nuvoton,wpcm450-clk.yaml
create mode 100644 include/dt-bindings/clock/nuvoton,wpcm450-clk.h
diff --git a/Documentation/devicetree/bindings/clock/nuvoton,wpcm450-clk.yaml b/Documentation/devicetree/bindings/clock/nuvoton,wpcm450-clk.yaml
new file mode 100644
index 0000000000000..525024a58df4c
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/nuvoton,wpcm450-clk.yaml
@@ -0,0 +1,66 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/clock/nuvoton,wpcm450-clk.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Nuvoton WPCM450 clock controller
+
+maintainers:
+ - Jonathan Neuschäfer <j.neuschaefer@gmx.net>
+
+description:
+ The clock controller of the Nuvoton WPCM450 SoC supplies clocks and resets to
+ the rest of the chip.
+
+properties:
+ compatible:
+ const: nuvoton,wpcm450-clk
+
+ reg:
+ maxItems: 1
+
+ clocks:
+ items:
+ - description: Reference clock oscillator (should be 48 MHz)
+
+ clock-names:
+ items:
+ - const: ref
+
+ '#clock-cells':
+ const: 1
+
+ '#reset-cells':
+ const: 1
+
+additionalProperties: false
+
+required:
+ - compatible
+ - reg
+ - clocks
+ - clock-names
+ - '#clock-cells'
+
+examples:
+ - |
+ #include <dt-bindings/clock/nuvoton,wpcm450-clk.h>
+ #include <dt-bindings/interrupt-controller/irq.h>
+
+ refclk: clock-48mhz {
+ /* 48 MHz reference oscillator */
+ compatible = "fixed-clock";
+ clock-output-names = "ref";
+ clock-frequency = <48000000>;
+ #clock-cells = <0>;
+ };
+
+ clk: clock-controller@b0000200 {
+ reg = <0xb0000200 0x100>;
+ compatible = "nuvoton,wpcm450-clk";
+ clocks = <&refclk>;
+ clock-names = "ref";
+ #clock-cells = <1>;
+ #reset-cells = <1>;
+ };
diff --git a/include/dt-bindings/clock/nuvoton,wpcm450-clk.h b/include/dt-bindings/clock/nuvoton,wpcm450-clk.h
new file mode 100644
index 0000000000000..86e1c895921b7
--- /dev/null
+++ b/include/dt-bindings/clock/nuvoton,wpcm450-clk.h
@@ -0,0 +1,67 @@
+/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
+
+#ifndef _DT_BINDINGS_CLOCK_NUVOTON_WPCM450_CLK_H
+#define _DT_BINDINGS_CLOCK_NUVOTON_WPCM450_CLK_H
+
+/* Clocks based on CLKEN bits */
+#define WPCM450_CLK_FIU 0
+#define WPCM450_CLK_XBUS 1
+#define WPCM450_CLK_KCS 2
+#define WPCM450_CLK_SHM 4
+#define WPCM450_CLK_USB1 5
+#define WPCM450_CLK_EMC0 6
+#define WPCM450_CLK_EMC1 7
+#define WPCM450_CLK_USB0 8
+#define WPCM450_CLK_PECI 9
+#define WPCM450_CLK_AES 10
+#define WPCM450_CLK_UART0 11
+#define WPCM450_CLK_UART1 12
+#define WPCM450_CLK_SMB2 13
+#define WPCM450_CLK_SMB3 14
+#define WPCM450_CLK_SMB4 15
+#define WPCM450_CLK_SMB5 16
+#define WPCM450_CLK_HUART 17
+#define WPCM450_CLK_PWM 18
+#define WPCM450_CLK_TIMER0 19
+#define WPCM450_CLK_TIMER1 20
+#define WPCM450_CLK_TIMER2 21
+#define WPCM450_CLK_TIMER3 22
+#define WPCM450_CLK_TIMER4 23
+#define WPCM450_CLK_MFT0 24
+#define WPCM450_CLK_MFT1 25
+#define WPCM450_CLK_WDT 26
+#define WPCM450_CLK_ADC 27
+#define WPCM450_CLK_SDIO 28
+#define WPCM450_CLK_SSPI 29
+#define WPCM450_CLK_SMB0 30
+#define WPCM450_CLK_SMB1 31
+
+/* Other clocks */
+#define WPCM450_CLK_USBPHY 32
+
+#define WPCM450_NUM_CLKS 33
+
+/* Resets based on IPSRST bits */
+#define WPCM450_RESET_FIU 0
+#define WPCM450_RESET_EMC0 6
+#define WPCM450_RESET_EMC1 7
+#define WPCM450_RESET_USB0 8
+#define WPCM450_RESET_USB1 9
+#define WPCM450_RESET_AES_PECI 10
+#define WPCM450_RESET_UART 11
+#define WPCM450_RESET_MC 12
+#define WPCM450_RESET_SMB2 13
+#define WPCM450_RESET_SMB3 14
+#define WPCM450_RESET_SMB4 15
+#define WPCM450_RESET_SMB5 16
+#define WPCM450_RESET_PWM 18
+#define WPCM450_RESET_TIMER 19
+#define WPCM450_RESET_ADC 27
+#define WPCM450_RESET_SDIO 28
+#define WPCM450_RESET_SSPI 29
+#define WPCM450_RESET_SMB0 30
+#define WPCM450_RESET_SMB1 31
+
+#define WPCM450_NUM_RESETS 32
+
+#endif /* _DT_BINDINGS_CLOCK_NUVOTON_WPCM450_CLK_H */
--
2.35.1
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH v4 4/6] ARM: dts: wpcm450: Add clock controller node
2022-06-10 7:21 [PATCH v4 0/6] Nuvoton WPCM450 clock and reset driver Jonathan Neuschäfer
` (2 preceding siblings ...)
2022-06-10 7:21 ` [PATCH v4 3/6] dt-bindings: clock: Add Nuvoton WPCM450 clock/reset controller Jonathan Neuschäfer
@ 2022-06-10 7:21 ` Jonathan Neuschäfer
2022-06-10 7:21 ` [PATCH v4 5/6] clk: wpcm450: Add Nuvoton WPCM450 clock/reset controller driver Jonathan Neuschäfer
2022-06-10 7:21 ` [PATCH v4 6/6] ARM: dts: wpcm450: Switch clocks to clock controller Jonathan Neuschäfer
5 siblings, 0 replies; 8+ messages in thread
From: Jonathan Neuschäfer @ 2022-06-10 7:21 UTC (permalink / raw)
To: linux-clk, openbmc
Cc: linux-kernel, linux-watchdog, devicetree,
Jonathan Neuschäfer, Michael Turquette, Stephen Boyd,
Rob Herring, Krzysztof Kozlowski, Avi Fishman, Tomer Maimon,
Tali Perry, Patrick Venture, Nancy Yuen, Benjamin Fair,
Daniel Lezcano, Thomas Gleixner, Philipp Zabel, Wim Van Sebroeck,
Guenter Roeck, Krzysztof Kozlowski
This declares the clock controller and the necessary 48 Mhz reference
clock in the WPCM450 device. Switching devices over to the clock
controller is intentionally done in a separate patch to give time for
the clock controller driver to land.
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
---
v4:
- no changes
v3:
- Change clock-output-names and clock-names from "refclk" to "ref"
v2:
- https://lore.kernel.org/lkml/20220429172030.398011-6-j.neuschaefer@gmx.net/
- no changes
---
arch/arm/boot/dts/nuvoton-wpcm450.dtsi | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/arch/arm/boot/dts/nuvoton-wpcm450.dtsi b/arch/arm/boot/dts/nuvoton-wpcm450.dtsi
index b9b669cd632f1..332cc222c7dc5 100644
--- a/arch/arm/boot/dts/nuvoton-wpcm450.dtsi
+++ b/arch/arm/boot/dts/nuvoton-wpcm450.dtsi
@@ -37,6 +37,14 @@ clk24m: clock-24mhz {
#clock-cells = <0>;
};
+ refclk: clock-48mhz {
+ /* 48 MHz reference oscillator */
+ compatible = "fixed-clock";
+ clock-output-names = "ref";
+ clock-frequency = <48000000>;
+ #clock-cells = <0>;
+ };
+
soc {
compatible = "simple-bus";
#address-cells = <1>;
@@ -49,6 +57,15 @@ gcr: syscon@b0000000 {
reg = <0xb0000000 0x200>;
};
+ clk: clock-controller@b0000200 {
+ compatible = "nuvoton,wpcm450-clk";
+ reg = <0xb0000200 0x100>;
+ clocks = <&refclk>;
+ clock-names = "ref";
+ #clock-cells = <1>;
+ #reset-cells = <1>;
+ };
+
serial0: serial@b8000000 {
compatible = "nuvoton,wpcm450-uart";
reg = <0xb8000000 0x20>;
--
2.35.1
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH v4 5/6] clk: wpcm450: Add Nuvoton WPCM450 clock/reset controller driver
2022-06-10 7:21 [PATCH v4 0/6] Nuvoton WPCM450 clock and reset driver Jonathan Neuschäfer
` (3 preceding siblings ...)
2022-06-10 7:21 ` [PATCH v4 4/6] ARM: dts: wpcm450: Add clock controller node Jonathan Neuschäfer
@ 2022-06-10 7:21 ` Jonathan Neuschäfer
2022-06-10 7:21 ` [PATCH v4 6/6] ARM: dts: wpcm450: Switch clocks to clock controller Jonathan Neuschäfer
5 siblings, 0 replies; 8+ messages in thread
From: Jonathan Neuschäfer @ 2022-06-10 7:21 UTC (permalink / raw)
To: linux-clk, openbmc
Cc: linux-kernel, linux-watchdog, devicetree,
Jonathan Neuschäfer, Michael Turquette, Stephen Boyd,
Rob Herring, Krzysztof Kozlowski, Avi Fishman, Tomer Maimon,
Tali Perry, Patrick Venture, Nancy Yuen, Benjamin Fair,
Daniel Lezcano, Thomas Gleixner, Philipp Zabel, Wim Van Sebroeck,
Guenter Roeck
This driver implements the following features w.r.t. the clock and reset
controller in the WPCM450 SoC:
- It calculates the rates for all clocks managed by the clock controller
- It leaves the clock tree mostly unchanged, except that it enables/
disables clock gates based on usage.
- It exposes the reset lines managed by the controller using the
Generic Reset Controller subsystem
NOTE: If the driver and the corresponding devicetree node are present,
the driver will disable "unused" clocks. This is problem until
the clock relations are properly declared in the devicetree (in a
later patch). Until then, the clk_ignore_unused kernel parameter
can be used as a workaround.
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
---
v4:
- Fix reset controller initialization
v3:
- https://lore.kernel.org/lkml/20220508194333.2170161-7-j.neuschaefer@gmx.net/
- Change reference clock name from "refclk" to "ref"
- Remove unused variable in return path of wpcm450_clk_register_pll
- Remove unused divisor tables
v2:
- https://lore.kernel.org/lkml/20220429172030.398011-7-j.neuschaefer@gmx.net/
- no changes
---
drivers/clk/Makefile | 1 +
drivers/clk/clk-wpcm450.c | 364 ++++++++++++++++++++++++++++++++++++++
drivers/reset/Kconfig | 2 +-
3 files changed, 366 insertions(+), 1 deletion(-)
create mode 100644 drivers/clk/clk-wpcm450.c
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index d5db170d38d2d..d6737e6d62feb 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -74,6 +74,7 @@ obj-$(CONFIG_ARCH_VT8500) += clk-vt8500.o
obj-$(CONFIG_COMMON_CLK_RS9_PCIE) += clk-renesas-pcie.o
obj-$(CONFIG_COMMON_CLK_VC5) += clk-versaclock5.o
obj-$(CONFIG_COMMON_CLK_WM831X) += clk-wm831x.o
+obj-$(CONFIG_ARCH_WPCM450) += clk-wpcm450.o
obj-$(CONFIG_COMMON_CLK_XGENE) += clk-xgene.o
# please keep this section sorted lexicographically by directory path name
diff --git a/drivers/clk/clk-wpcm450.c b/drivers/clk/clk-wpcm450.c
new file mode 100644
index 0000000000000..88fe5583e009d
--- /dev/null
+++ b/drivers/clk/clk-wpcm450.c
@@ -0,0 +1,364 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Nuvoton WPCM450 clock and reset controller driver.
+ *
+ * Copyright (C) 2022 Jonathan Neuschäfer <j.neuschaefer@gmx.net>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/bitfield.h>
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/reset-controller.h>
+#include <linux/reset/reset-simple.h>
+#include <linux/slab.h>
+
+#include <dt-bindings/clock/nuvoton,wpcm450-clk.h>
+
+struct wpcm450_clk_pll {
+ struct clk_hw hw;
+ void __iomem *pllcon;
+ u8 flags;
+};
+
+#define to_wpcm450_clk_pll(_hw) container_of(_hw, struct wpcm450_clk_pll, hw)
+
+#define PLLCON_FBDV GENMASK(24, 16)
+#define PLLCON_PRST BIT(13)
+#define PLLCON_PWDEN BIT(12)
+#define PLLCON_OTDV GENMASK(10, 8)
+#define PLLCON_INDV GENMASK(5, 0)
+
+static unsigned long wpcm450_clk_pll_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct wpcm450_clk_pll *pll = to_wpcm450_clk_pll(hw);
+ unsigned long fbdv, indv, otdv;
+ u64 rate;
+ u32 pllcon;
+
+ if (parent_rate == 0) {
+ pr_err("%s: parent rate is zero", __func__);
+ return 0;
+ }
+
+ pllcon = readl_relaxed(pll->pllcon);
+
+ indv = FIELD_GET(PLLCON_INDV, pllcon) + 1;
+ fbdv = FIELD_GET(PLLCON_FBDV, pllcon) + 1;
+ otdv = FIELD_GET(PLLCON_OTDV, pllcon) + 1;
+
+ rate = (u64)parent_rate * fbdv;
+ do_div(rate, indv * otdv);
+
+ return rate;
+}
+
+static int wpcm450_clk_pll_is_enabled(struct clk_hw *hw)
+{
+ struct wpcm450_clk_pll *pll = to_wpcm450_clk_pll(hw);
+ u32 pllcon;
+
+ pllcon = readl_relaxed(pll->pllcon);
+
+ return !(pllcon & PLLCON_PRST);
+}
+
+static void wpcm450_clk_pll_disable(struct clk_hw *hw)
+{
+ struct wpcm450_clk_pll *pll = to_wpcm450_clk_pll(hw);
+ u32 pllcon;
+
+ pllcon = readl_relaxed(pll->pllcon);
+ pllcon |= PLLCON_PRST | PLLCON_PWDEN;
+ writel(pllcon, pll->pllcon);
+}
+
+static const struct clk_ops wpcm450_clk_pll_ops = {
+ .recalc_rate = wpcm450_clk_pll_recalc_rate,
+ .is_enabled = wpcm450_clk_pll_is_enabled,
+ .disable = wpcm450_clk_pll_disable
+};
+
+static struct clk_hw *
+wpcm450_clk_register_pll(void __iomem *pllcon, const char *name,
+ const char *parent_name, unsigned long flags)
+{
+ struct wpcm450_clk_pll *pll;
+ struct clk_init_data init;
+ int ret;
+
+ pll = kzalloc(sizeof(*pll), GFP_KERNEL);
+ if (!pll)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &wpcm450_clk_pll_ops;
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
+ init.flags = flags;
+
+ pll->pllcon = pllcon;
+ pll->hw.init = &init;
+
+ ret = clk_hw_register(NULL, &pll->hw);
+ if (ret) {
+ kfree(pll);
+ return ERR_PTR(ret);
+ }
+
+ return &pll->hw;
+}
+
+#define REG_CLKEN 0x00
+#define REG_CLKSEL 0x04
+#define REG_CLKDIV 0x08
+#define REG_PLLCON0 0x0c
+#define REG_PLLCON1 0x10
+#define REG_PMCON 0x14
+#define REG_IRQWAKECON 0x18
+#define REG_IRQWAKEFLAG 0x1c
+#define REG_IPSRST 0x20
+
+struct wpcm450_pll_data {
+ const char *name;
+ const char *parent_name;
+ unsigned int reg;
+ unsigned long flags;
+};
+
+static const struct wpcm450_pll_data pll_data[] = {
+ { "pll0", "ref", REG_PLLCON0, 0 },
+ { "pll1", "ref", REG_PLLCON1, 0 },
+};
+
+struct wpcm450_clksel_data {
+ const char *name;
+ const char *const *parent_names;
+ unsigned int num_parents;
+ const u32 *table;
+ int shift;
+ int width;
+ int index;
+ unsigned long flags;
+};
+
+static const u32 parent_table[] = { 0, 1, 2 };
+static const char *const default_parents[] = { "pll0", "pll1", "ref" };
+static const char *const huart_parents[] = { "ref", "refdiv2" };
+
+static const struct wpcm450_clksel_data clksel_data[] = {
+ { "cpusel", default_parents, ARRAY_SIZE(default_parents),
+ parent_table, 0, 2, -1, CLK_IS_CRITICAL },
+ { "clkout", default_parents, ARRAY_SIZE(default_parents),
+ parent_table, 2, 2, -1, 0 },
+ { "usbphy", default_parents, ARRAY_SIZE(default_parents),
+ parent_table, 6, 2, -1, 0 },
+ { "uartsel", default_parents, ARRAY_SIZE(default_parents),
+ parent_table, 8, 2, WPCM450_CLK_USBPHY, 0 },
+ { "huartsel", huart_parents, ARRAY_SIZE(huart_parents),
+ parent_table, 10, 1, -1, 0 },
+};
+
+static const struct clk_div_table div_fixed2[] = {
+ { .val = 0, .div = 2 },
+ { }
+};
+
+struct wpcm450_clkdiv_data {
+ const char *name;
+ const char *parent_name;
+ int div_flags;
+ const struct clk_div_table *table;
+ int shift;
+ int width;
+ unsigned long flags;
+};
+
+static struct wpcm450_clkdiv_data clkdiv_data_early[] = {
+ { "refdiv2", "ref", 0, div_fixed2, 0, 0 },
+};
+
+static const struct wpcm450_clkdiv_data clkdiv_data[] = {
+ { "cpu", "cpusel", 0, div_fixed2, 0, 0, CLK_IS_CRITICAL },
+ { "adcdiv", "ref", CLK_DIVIDER_POWER_OF_TWO, NULL, 28, 2, 0 },
+ { "apb", "ahb", CLK_DIVIDER_POWER_OF_TWO, NULL, 26, 2, 0 },
+ { "ahb", "cpu", CLK_DIVIDER_POWER_OF_TWO, NULL, 24, 2, 0 },
+ { "uart", "uartsel", 0, NULL, 16, 4, 0 },
+ { "ahb3", "ahb", CLK_DIVIDER_POWER_OF_TWO, NULL, 8, 2, 0 },
+};
+
+struct wpcm450_clken_data {
+ const char *name;
+ const char *parent_name;
+ int bitnum;
+ unsigned long flags;
+};
+
+static const struct wpcm450_clken_data clken_data[] = {
+ { "fiu", "ahb3", WPCM450_CLK_FIU, 0 },
+ { "xbus", "ahb3", WPCM450_CLK_XBUS, 0 },
+ { "kcs", "apb", WPCM450_CLK_KCS, 0 },
+ { "shm", "ahb3", WPCM450_CLK_SHM, 0 },
+ { "usb1", "ahb", WPCM450_CLK_USB1, 0 },
+ { "emc0", "ahb", WPCM450_CLK_EMC0, 0 },
+ { "emc1", "ahb", WPCM450_CLK_EMC1, 0 },
+ { "usb0", "ahb", WPCM450_CLK_USB0, 0 },
+ { "peci", "apb", WPCM450_CLK_PECI, 0 },
+ { "aes", "apb", WPCM450_CLK_AES, 0 },
+ { "uart0", "uart", WPCM450_CLK_UART0, 0 },
+ { "uart1", "uart", WPCM450_CLK_UART1, 0 },
+ { "smb2", "apb", WPCM450_CLK_SMB2, 0 },
+ { "smb3", "apb", WPCM450_CLK_SMB3, 0 },
+ { "smb4", "apb", WPCM450_CLK_SMB4, 0 },
+ { "smb5", "apb", WPCM450_CLK_SMB5, 0 },
+ { "huart", "huartsel", WPCM450_CLK_HUART, 0 },
+ { "pwm", "apb", WPCM450_CLK_PWM, 0 },
+ { "timer0", "refdiv2", WPCM450_CLK_TIMER0, 0 },
+ { "timer1", "refdiv2", WPCM450_CLK_TIMER1, 0 },
+ { "timer2", "refdiv2", WPCM450_CLK_TIMER2, 0 },
+ { "timer3", "refdiv2", WPCM450_CLK_TIMER3, 0 },
+ { "timer4", "refdiv2", WPCM450_CLK_TIMER4, 0 },
+ { "mft0", "apb", WPCM450_CLK_MFT0, 0 },
+ { "mft1", "apb", WPCM450_CLK_MFT1, 0 },
+ { "wdt", "refdiv2", WPCM450_CLK_WDT, 0 },
+ { "adc", "adcdiv", WPCM450_CLK_ADC, 0 },
+ { "sdio", "ahb", WPCM450_CLK_SDIO, 0 },
+ { "sspi", "apb", WPCM450_CLK_SSPI, 0 },
+ { "smb0", "apb", WPCM450_CLK_SMB0, 0 },
+ { "smb1", "apb", WPCM450_CLK_SMB1, 0 },
+};
+
+static DEFINE_SPINLOCK(wpcm450_clk_lock);
+
+static void __init wpcm450_clk_init(struct device_node *clk_np)
+{
+ struct clk_hw_onecell_data *clk_data;
+ static struct clk_hw **hws;
+ static struct clk_hw *hw;
+ void __iomem *clk_base;
+ int i, ret;
+ struct reset_simple_data *reset;
+
+ clk_base = of_iomap(clk_np, 0);
+ if (!clk_base) {
+ pr_err("%pOFP: failed to map registers\n", clk_np);
+ of_node_put(clk_np);
+ return;
+ }
+ of_node_put(clk_np);
+
+ clk_data = kzalloc(struct_size(clk_data, hws, WPCM450_NUM_CLKS), GFP_KERNEL);
+ if (!clk_data)
+ goto err_unmap;
+
+ clk_data->num = WPCM450_NUM_CLKS;
+ hws = clk_data->hws;
+
+ for (i = 0; i < WPCM450_NUM_CLKS; i++)
+ hws[i] = ERR_PTR(-ENOENT);
+
+ // PLLs
+ for (i = 0; i < ARRAY_SIZE(pll_data); i++) {
+ const struct wpcm450_pll_data *data = &pll_data[i];
+
+ hw = wpcm450_clk_register_pll(clk_base + data->reg, data->name,
+ data->parent_name, data->flags);
+ if (IS_ERR(hw)) {
+ pr_info("Failed to register PLL: %pe", hw);
+ goto err_free;
+ }
+ }
+
+ // Early divisors (REF/2)
+ for (i = 0; i < ARRAY_SIZE(clkdiv_data_early); i++) {
+ const struct wpcm450_clkdiv_data *data = &clkdiv_data_early[i];
+
+ hw = clk_hw_register_divider_table(NULL, data->name, data->parent_name,
+ data->flags, clk_base + REG_CLKDIV,
+ data->shift, data->width, data->div_flags,
+ data->table, &wpcm450_clk_lock);
+ if (IS_ERR(hw)) {
+ pr_err("Failed to register div table: %pe\n", hw);
+ goto err_free;
+ }
+ }
+
+ // Selects/muxes
+ for (i = 0; i < ARRAY_SIZE(clksel_data); i++) {
+ const struct wpcm450_clksel_data *data = &clksel_data[i];
+
+ hw = clk_hw_register_mux_table(NULL, data->name, data->parent_names,
+ data->num_parents, data->flags,
+ clk_base + REG_CLKSEL, data->shift,
+ BIT(data->width) - 1, 0, data->table,
+ &wpcm450_clk_lock);
+ if (IS_ERR(hw)) {
+ pr_err("Failed to register mux: %pe\n", hw);
+ goto err_free;
+ }
+ if (data->index >= 0)
+ clk_data->hws[data->index] = hw;
+ }
+
+ // Divisors
+ for (i = 0; i < ARRAY_SIZE(clkdiv_data); i++) {
+ const struct wpcm450_clkdiv_data *data = &clkdiv_data[i];
+
+ hw = clk_hw_register_divider_table(NULL, data->name, data->parent_name,
+ data->flags, clk_base + REG_CLKDIV,
+ data->shift, data->width, data->div_flags,
+ data->table, &wpcm450_clk_lock);
+ if (IS_ERR(hw)) {
+ pr_err("Failed to register divider: %pe\n", hw);
+ goto err_free;
+ }
+ }
+
+ // Enables/gates
+ for (i = 0; i < ARRAY_SIZE(clken_data); i++) {
+ const struct wpcm450_clken_data *data = &clken_data[i];
+
+ hw = clk_hw_register_gate(NULL, data->name, data->parent_name, data->flags,
+ clk_base + REG_CLKEN, data->bitnum,
+ data->flags, &wpcm450_clk_lock);
+ if (IS_ERR(hw)) {
+ pr_err("Failed to register gate: %pe\n", hw);
+ goto err_free;
+ }
+ clk_data->hws[data->bitnum] = hw;
+ }
+
+ ret = of_clk_add_hw_provider(clk_np, of_clk_hw_onecell_get, clk_data);
+ if (ret)
+ pr_err("Failed to add DT provider: %d\n", ret);
+
+ // Reset controller
+ reset = kzalloc(sizeof(*reset), GFP_KERNEL);
+ if (!reset)
+ goto err_free;
+ reset->rcdev.owner = THIS_MODULE;
+ reset->rcdev.nr_resets = WPCM450_NUM_RESETS;
+ reset->rcdev.ops = &reset_simple_ops;
+ reset->rcdev.of_node = clk_np;
+ reset->membase = clk_base + REG_IPSRST;
+ ret = reset_controller_register(&reset->rcdev);
+ if (ret)
+ pr_err("Failed to register reset controller: %d\n", ret);
+
+ of_node_put(clk_np);
+ return;
+
+err_free:
+ kfree(clk_data->hws);
+err_unmap:
+ iounmap(clk_base);
+ of_node_put(clk_np);
+}
+
+CLK_OF_DECLARE(wpcm450_clk_init, "nuvoton,wpcm450-clk", wpcm450_clk_init);
diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig
index 93c8d07ee3280..1e9badf8878bb 100644
--- a/drivers/reset/Kconfig
+++ b/drivers/reset/Kconfig
@@ -201,7 +201,7 @@ config RESET_SCMI
config RESET_SIMPLE
bool "Simple Reset Controller Driver" if COMPILE_TEST
- default ARCH_ASPEED || ARCH_BCM4908 || ARCH_BITMAIN || ARCH_REALTEK || ARCH_STM32 || (ARCH_INTEL_SOCFPGA && ARM64) || ARCH_SUNXI || ARC
+ default ARCH_ASPEED || ARCH_BCM4908 || ARCH_BITMAIN || ARCH_REALTEK || ARCH_STM32 || (ARCH_INTEL_SOCFPGA && ARM64) || ARCH_SUNXI || ARC || ARCH_NPCM
help
This enables a simple reset controller driver for reset lines that
that can be asserted and deasserted by toggling bits in a contiguous,
--
2.35.1
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH v4 6/6] ARM: dts: wpcm450: Switch clocks to clock controller
2022-06-10 7:21 [PATCH v4 0/6] Nuvoton WPCM450 clock and reset driver Jonathan Neuschäfer
` (4 preceding siblings ...)
2022-06-10 7:21 ` [PATCH v4 5/6] clk: wpcm450: Add Nuvoton WPCM450 clock/reset controller driver Jonathan Neuschäfer
@ 2022-06-10 7:21 ` Jonathan Neuschäfer
5 siblings, 0 replies; 8+ messages in thread
From: Jonathan Neuschäfer @ 2022-06-10 7:21 UTC (permalink / raw)
To: linux-clk, openbmc
Cc: linux-kernel, linux-watchdog, devicetree,
Jonathan Neuschäfer, Michael Turquette, Stephen Boyd,
Rob Herring, Krzysztof Kozlowski, Avi Fishman, Tomer Maimon,
Tali Perry, Patrick Venture, Nancy Yuen, Benjamin Fair,
Daniel Lezcano, Thomas Gleixner, Philipp Zabel, Wim Van Sebroeck,
Guenter Roeck, Krzysztof Kozlowski
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 <j.neuschaefer@gmx.net>
---
v2-v4:
- 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 332cc222c7dc5..439f9047ad651 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";
@@ -30,13 +31,6 @@ 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";
@@ -71,7 +65,7 @@ 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";
@@ -82,7 +76,7 @@ serial1: serial@b8000100 {
reg = <0xb8000100 0x20>;
reg-shift = <2>;
interrupts = <8 IRQ_TYPE_LEVEL_HIGH>;
- clocks = <&clk24m>;
+ clocks = <&clk WPCM450_CLK_UART1>;
status = "disabled";
};
@@ -90,14 +84,18 @@ 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
^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH v4 2/6] watchdog: npcm: Enable clock if provided
2022-06-10 7:21 ` [PATCH v4 2/6] watchdog: npcm: Enable clock if provided Jonathan Neuschäfer
@ 2022-09-25 17:00 ` Guenter Roeck
0 siblings, 0 replies; 8+ messages in thread
From: Guenter Roeck @ 2022-09-25 17:00 UTC (permalink / raw)
To: Jonathan Neuschäfer
Cc: linux-clk, openbmc, linux-kernel, linux-watchdog, devicetree,
Michael Turquette, Stephen Boyd, Rob Herring,
Krzysztof Kozlowski, Avi Fishman, Tomer Maimon, Tali Perry,
Patrick Venture, Nancy Yuen, Benjamin Fair, Daniel Lezcano,
Thomas Gleixner, Philipp Zabel, Wim Van Sebroeck
On Fri, Jun 10, 2022 at 09:21:37AM +0200, Jonathan Neuschäfer wrote:
> On the Nuvoton WPCM450 SoC, with its upcoming clock driver, peripheral
> clocks are individually gated and ungated. Therefore, the watchdog
> driver must be able to ungate the watchdog clock.
>
> Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
> ---
>
> v4:
> - Don't disable clock in npcm_wdt_restart function
>
> v3:
> - https://lore.kernel.org/lkml/20220508194333.2170161-4-j.neuschaefer@gmx.net/
> - Add enable/disable calls to npcm_wdt_restart handler
> - Not applied due to the above change: Acked-by: Guenter Roeck <linux@roeck-us.net>
>
> v2:
> - https://lore.kernel.org/lkml/20220429172030.398011-4-j.neuschaefer@gmx.net/
> - Add clk_disable_unprepare call, suggested by Guenter Roeck
>
> v1:
> - https://lore.kernel.org/lkml/20220422183012.444674-4-j.neuschaefer@gmx.net/
> ---
> drivers/watchdog/npcm_wdt.c | 16 ++++++++++++++++
> 1 file changed, 16 insertions(+)
>
> --
> 2.35.1
>
> diff --git a/drivers/watchdog/npcm_wdt.c b/drivers/watchdog/npcm_wdt.c
> index 28a24caa2627c..a5dd1c2301374 100644
> --- a/drivers/watchdog/npcm_wdt.c
> +++ b/drivers/watchdog/npcm_wdt.c
> @@ -3,6 +3,7 @@
> // Copyright (c) 2018 IBM Corp.
>
> #include <linux/bitops.h>
> +#include <linux/clk.h>
> #include <linux/delay.h>
> #include <linux/interrupt.h>
> #include <linux/kernel.h>
> @@ -43,6 +44,7 @@
> struct npcm_wdt {
> struct watchdog_device wdd;
> void __iomem *reg;
> + struct clk *clk;
> };
>
> static inline struct npcm_wdt *to_npcm_wdt(struct watchdog_device *wdd)
> @@ -66,6 +68,9 @@ static int npcm_wdt_start(struct watchdog_device *wdd)
> struct npcm_wdt *wdt = to_npcm_wdt(wdd);
> u32 val;
>
> + if (wdt->clk)
> + clk_prepare_enable(wdt->clk);
> +
> if (wdd->timeout < 2)
> val = 0x800;
> else if (wdd->timeout < 3)
> @@ -100,6 +105,9 @@ static int npcm_wdt_stop(struct watchdog_device *wdd)
>
> writel(0, wdt->reg);
>
> + if (wdt->clk)
> + clk_disable_unprepare(wdt->clk);
> +
> return 0;
> }
>
> @@ -147,6 +155,10 @@ static int npcm_wdt_restart(struct watchdog_device *wdd,
> {
> struct npcm_wdt *wdt = to_npcm_wdt(wdd);
>
> + /* For reset, we start the WDT clock and leave it running. */
> + if (wdt->clk)
> + clk_prepare_enable(wdt->clk);
> +
> writel(NPCM_WTR | NPCM_WTRE | NPCM_WTE, wdt->reg);
> udelay(1000);
>
> @@ -191,6 +203,10 @@ static int npcm_wdt_probe(struct platform_device *pdev)
> if (IS_ERR(wdt->reg))
> return PTR_ERR(wdt->reg);
>
> + wdt->clk = devm_clk_get_optional(&pdev->dev, NULL);
> + if (IS_ERR(wdt->clk))
> + return PTR_ERR(wdt->clk);
> +
> irq = platform_get_irq(pdev, 0);
> if (irq < 0)
> return irq;
^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2022-09-25 17:01 UTC | newest]
Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-06-10 7:21 [PATCH v4 0/6] Nuvoton WPCM450 clock and reset driver Jonathan Neuschäfer
2022-06-10 7:21 ` [PATCH v4 1/6] dt-bindings: timer: nuvoton,npcm7xx-timer: Allow specifying all clocks Jonathan Neuschäfer
2022-06-10 7:21 ` [PATCH v4 2/6] watchdog: npcm: Enable clock if provided Jonathan Neuschäfer
2022-09-25 17:00 ` Guenter Roeck
2022-06-10 7:21 ` [PATCH v4 3/6] dt-bindings: clock: Add Nuvoton WPCM450 clock/reset controller Jonathan Neuschäfer
2022-06-10 7:21 ` [PATCH v4 4/6] ARM: dts: wpcm450: Add clock controller node Jonathan Neuschäfer
2022-06-10 7:21 ` [PATCH v4 5/6] clk: wpcm450: Add Nuvoton WPCM450 clock/reset controller driver Jonathan Neuschäfer
2022-06-10 7:21 ` [PATCH v4 6/6] ARM: dts: wpcm450: Switch clocks to clock controller Jonathan Neuschäfer
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