[PATCH v4 0/3] Add support for Allwinner PWM on D1/T113s/R329 SoCs

[PATCH v4 0/3] Add support for Allwinner PWM on D1/T113s/R329 SoCs

[Aleksandr Shubin]

Hi,

This series adds support for PWM controller on new
Allwinner's SoCs, such as D1, T113s and R329. The implemented driver
provides basic functionality for control PWM channels.

v2:
 - fix dt-bindings
 - fix a remark in the driver

v3:
 - fix dt-bindings
 - fix sunxi-d1s-t113.dtsi

v4:
 - fix a remark in the driver

Aleksandr Shubin (3):
  dt-bindings: pwm: Add binding for Allwinner D1/T113-S3/R329 PWM
    controller
  pwm: Add Allwinner's D1/T113-S3/R329 SoCs PWM support
  riscv: dts: allwinner: d1: Add pwm node

 .../bindings/pwm/allwinner,sun20i-pwm.yaml    |  86 +++++
 .../boot/dts/allwinner/sunxi-d1s-t113.dtsi    |  11 +
 drivers/pwm/Kconfig                           |  10 +
 drivers/pwm/Makefile                          |   1 +
 drivers/pwm/pwm-sun20i.c                      | 323 ++++++++++++++++++
 5 files changed, 431 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/pwm/allwinner,sun20i-pwm.yaml
 create mode 100644 drivers/pwm/pwm-sun20i.c

-- 
2.25.1

[PATCH v4 1/3] dt-bindings: pwm: Add binding for Allwinner D1/T113-S3/R329 PWM controller

[Aleksandr Shubin]

Allwinner's D1, T113-S3 and R329 SoCs have a new pwm
controller witch is different from the previous pwm-sun4i.

The D1 and T113 are identical in terms of peripherals,
they differ only in the architecture of the CPU core, and
even share the majority of their DT. Because of that,
using the same compatible makes sense.
The R329 is a different SoC though, and should have
a different compatible string added, especially as there
is a difference in the number of channels.

D1 and T113s SoCs have one PWM controller with 8 channels.
R329 SoC has two PWM controllers in both power domains, one of
them has 9 channels (CPUX one) and the other has 6 (CPUS one).

Add a device tree binding for them.

Signed-off-by: Aleksandr Shubin <privatesub2@gmail.com>
---
 .../bindings/pwm/allwinner,sun20i-pwm.yaml    | 86 +++++++++++++++++++
 1 file changed, 86 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/pwm/allwinner,sun20i-pwm.yaml

diff --git a/Documentation/devicetree/bindings/pwm/allwinner,sun20i-pwm.yaml b/Documentation/devicetree/bindings/pwm/allwinner,sun20i-pwm.yaml
new file mode 100644
index 000000000000..4e6eaa18f342
--- /dev/null
+++ b/Documentation/devicetree/bindings/pwm/allwinner,sun20i-pwm.yaml
@@ -0,0 +1,86 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pwm/allwinner,sun20i-pwm.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Allwinner D1, T113-S3 and R329 PWM
+
+maintainers:
+  - Aleksandr Shubin <privatesub2@gmail.com>
+
+properties:
+  compatible:
+    oneOf:
+      - const: allwinner,sun20i-d1-pwm
+      - items:
+          - const: allwinner,sun20i-r329-pwm
+          - const: allwinner,sun20i-d1-pwm
+
+  reg:
+    maxItems: 1
+
+  "#pwm-cells":
+    const: 3
+
+  clocks:
+    items:
+      - description: 24 MHz oscillator
+      - description: Bus Clock
+
+  clock-names:
+    items:
+      - const: hosc
+      - const: bus
+
+  resets:
+    maxItems: 1
+
+  allwinner,pwm-channels:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description: The number of PWM channels configured for this instance
+    enum: [6, 9]
+
+allOf:
+  - $ref: pwm.yaml#
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: allwinner,sun20i-r329-pwm
+
+    then:
+      required:
+        - allwinner,pwm-channels
+
+    else:
+      not:
+        required:
+          - allwinner,pwm-channels
+
+unevaluatedProperties: false
+
+required:
+  - compatible
+  - reg
+  - "#pwm-cells"
+  - clocks
+  - clock-names
+  - resets
+
+examples:
+  - |
+    #include <dt-bindings/clock/sun20i-d1-ccu.h>
+    #include <dt-bindings/reset/sun20i-d1-ccu.h>
+
+    pwm: pwm@2000c00 {
+      compatible = "allwinner,sun20i-d1-pwm";
+      reg = <0x02000c00 0x400>;
+      clocks = <&dcxo>, <&ccu CLK_BUS_PWM>;
+      clock-names = "hosc", "bus";
+      resets = <&ccu RST_BUS_PWM>;
+      #pwm-cells = <0x3>;
+    };
+
+...
-- 
2.25.1

[PATCH v4 2/3] pwm: Add Allwinner's D1/T113-S3/R329 SoCs PWM support

[Aleksandr Shubin]

Allwinner's D1, T113-S3 and R329 SoCs have a quite different PWM
controllers with ones supported by pwm-sun4i driver.

This patch adds a PWM controller driver for Allwinner's D1,
T113-S3 and R329 SoCs. The main difference between these SoCs
is the number of channels defined by the DT property.

Signed-off-by: Aleksandr Shubin <privatesub2@gmail.com>
---
 drivers/pwm/Kconfig      |  10 ++
 drivers/pwm/Makefile     |   1 +
 drivers/pwm/pwm-sun20i.c | 323 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 334 insertions(+)
 create mode 100644 drivers/pwm/pwm-sun20i.c

diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index 8df861b1f4a3..05c48a36969e 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -594,6 +594,16 @@ config PWM_SUN4I
 	  To compile this driver as a module, choose M here: the module
 	  will be called pwm-sun4i.
 
+config PWM_SUN20I
+	tristate "Allwinner D1/T113s/R329 PWM support"
+	depends on ARCH_SUNXI || COMPILE_TEST
+	depends on COMMON_CLK
+	help
+	  Generic PWM framework driver for Allwinner D1/T113s/R329 SoCs.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-sun20i.
+
 config PWM_SUNPLUS
 	tristate "Sunplus PWM support"
 	depends on ARCH_SUNPLUS || COMPILE_TEST
diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile
index 19899b912e00..cea872e22c78 100644
--- a/drivers/pwm/Makefile
+++ b/drivers/pwm/Makefile
@@ -55,6 +55,7 @@ obj-$(CONFIG_PWM_STM32)		+= pwm-stm32.o
 obj-$(CONFIG_PWM_STM32_LP)	+= pwm-stm32-lp.o
 obj-$(CONFIG_PWM_STMPE)		+= pwm-stmpe.o
 obj-$(CONFIG_PWM_SUN4I)		+= pwm-sun4i.o
+obj-$(CONFIG_PWM_SUN20I)	+= pwm-sun20i.o
 obj-$(CONFIG_PWM_SUNPLUS)	+= pwm-sunplus.o
 obj-$(CONFIG_PWM_TEGRA)		+= pwm-tegra.o
 obj-$(CONFIG_PWM_TIECAP)	+= pwm-tiecap.o
diff --git a/drivers/pwm/pwm-sun20i.c b/drivers/pwm/pwm-sun20i.c
new file mode 100644
index 000000000000..e2d425b64066
--- /dev/null
+++ b/drivers/pwm/pwm-sun20i.c
@@ -0,0 +1,323 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PWM Controller Driver for sunxi platforms (D1, T113-S3 and R329)
+ *
+ * Limitations:
+ * - When the parameters change, current running period will not be completed
+ *   and run new settings immediately.
+ * - It output HIGH-Z state when PWM channel disabled.
+ *
+ * Copyright (c) 2023 Aleksandr Shubin <privatesub2@gmail.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/pwm.h>
+#include <linux/reset.h>
+
+#define PWM_CLK_CFG(chan)		(0x20 + (((chan) >> 1) * 0x4))
+#define PWM_CLK_CFG_SRC			GENMASK(8, 7)
+#define PWM_CLK_CFG_DIV_M		GENMASK(3, 0)
+
+#define PWM_CLK_GATE			0x40
+#define PWM_CLK_GATE_BYPASS(chan)	BIT((chan) - 16)
+#define PWM_CLK_GATE_GATING(chan)	BIT(chan)
+
+#define PWM_ENABLE			0x80
+#define PWM_ENABLE_EN(chan)		BIT(chan)
+
+#define PWM_CTL(chan)			(0x100 + (chan) * 0x20)
+#define PWM_CTL_ACT_STA			BIT(8)
+#define PWM_CTL_PRESCAL_K		GENMASK(7, 0)
+
+#define PWM_PERIOD(chan)		(0x104 + (chan) * 0x20)
+#define PWM_PERIOD_ENTIRE_CYCLE		GENMASK(31, 16)
+#define PWM_PERIOD_ACT_CYCLE		GENMASK(15, 0)
+
+#define PWM_MAGIC			(255 * 65535 + 2 * 65534 + 1)
+
+struct sun20i_pwm_chip {
+	struct clk *clk_bus, *clk_hosc;
+	struct reset_control *rst;
+	struct pwm_chip chip;
+	void __iomem *base;
+	/* Mutex to protect pwm apply state */
+	struct mutex mutex;
+};
+
+static inline struct sun20i_pwm_chip *to_sun20i_pwm_chip(struct pwm_chip *chip)
+{
+	return container_of(chip, struct sun20i_pwm_chip, chip);
+}
+
+static inline u32 sun20i_pwm_readl(struct sun20i_pwm_chip *chip,
+				   unsigned long offset)
+{
+	return readl(chip->base + offset);
+}
+
+static inline void sun20i_pwm_writel(struct sun20i_pwm_chip *chip,
+				     u32 val, unsigned long offset)
+{
+	writel(val, chip->base + offset);
+}
+
+static int sun20i_pwm_get_state(struct pwm_chip *chip,
+				struct pwm_device *pwm,
+				struct pwm_state *state)
+{
+	struct sun20i_pwm_chip *sun20i_chip = to_sun20i_pwm_chip(chip);
+	u16 ent_cycle, act_cycle, prescal;
+	u64 clk_rate, tmp;
+	u8 div_id;
+	u32 val;
+
+	mutex_lock(&sun20i_chip->mutex);
+
+	val = sun20i_pwm_readl(sun20i_chip, PWM_CLK_CFG(pwm->hwpwm));
+	div_id = FIELD_GET(PWM_CLK_CFG_DIV_M, val);
+	if (FIELD_GET(PWM_CLK_CFG_SRC, val) == 0)
+		clk_rate = clk_get_rate(sun20i_chip->clk_hosc);
+	else
+		clk_rate = clk_get_rate(sun20i_chip->clk_bus);
+
+	val = sun20i_pwm_readl(sun20i_chip, PWM_CTL(pwm->hwpwm));
+	state->polarity = (PWM_CTL_ACT_STA & val) ? PWM_POLARITY_NORMAL : PWM_POLARITY_INVERSED;
+
+	prescal = FIELD_GET(PWM_CTL_PRESCAL_K, val) + 1;
+
+	val = sun20i_pwm_readl(sun20i_chip, PWM_ENABLE);
+	state->enabled = (PWM_ENABLE_EN(pwm->hwpwm) & val) ? true : false;
+
+	val = sun20i_pwm_readl(sun20i_chip, PWM_PERIOD(pwm->hwpwm));
+	act_cycle = FIELD_GET(PWM_PERIOD_ACT_CYCLE, val);
+	ent_cycle = FIELD_GET(PWM_PERIOD_ENTIRE_CYCLE, val);
+
+	/*
+	 * The duration of the active phase should not be longer
+	 * than the duration of the period
+	 */
+	if (act_cycle > ent_cycle)
+		act_cycle = ent_cycle;
+
+	tmp = ((u64)(act_cycle) * prescal << div_id) * NSEC_PER_SEC;
+	state->duty_cycle = DIV_ROUND_UP_ULL(tmp, clk_rate);
+	tmp = ((u64)(ent_cycle) * prescal << div_id) * NSEC_PER_SEC;
+	state->period = DIV_ROUND_UP_ULL(tmp, clk_rate);
+	mutex_unlock(&sun20i_chip->mutex);
+
+	return 0;
+}
+
+static int sun20i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+			    const struct pwm_state *state)
+{
+	struct sun20i_pwm_chip *sun20i_chip = to_sun20i_pwm_chip(chip);
+	u32 clk_gate, clk_cfg, pwm_en, ctl, period;
+	u64 bus_rate, hosc_rate, clk_div, val, tmp;
+	u32 prescaler, div_m;
+	bool use_bus_clk;
+	int ret = 0;
+
+	mutex_lock(&sun20i_chip->mutex);
+
+	pwm_en = sun20i_pwm_readl(sun20i_chip, PWM_ENABLE);
+
+	if (state->enabled != pwm->state.enabled)
+		clk_gate = sun20i_pwm_readl(sun20i_chip, PWM_CLK_GATE);
+
+	if (state->enabled != pwm->state.enabled && !state->enabled) {
+		clk_gate &= ~PWM_CLK_GATE_GATING(pwm->hwpwm);
+		pwm_en &= ~PWM_ENABLE_EN(pwm->hwpwm);
+		sun20i_pwm_writel(sun20i_chip, pwm_en, PWM_ENABLE);
+		sun20i_pwm_writel(sun20i_chip, clk_gate, PWM_CLK_GATE);
+	}
+
+	if (state->polarity != pwm->state.polarity ||
+	    state->duty_cycle != pwm->state.duty_cycle ||
+	    state->period != pwm->state.period) {
+		ctl = sun20i_pwm_readl(sun20i_chip, PWM_CTL(pwm->hwpwm));
+		clk_cfg = sun20i_pwm_readl(sun20i_chip, PWM_CLK_CFG(pwm->hwpwm));
+		hosc_rate = clk_get_rate(sun20i_chip->clk_hosc);
+		bus_rate = clk_get_rate(sun20i_chip->clk_bus);
+		if (pwm_en & PWM_ENABLE_EN(pwm->hwpwm ^ 1)) {
+			/* if the neighbor channel is enable, check period only */
+			use_bus_clk = FIELD_GET(PWM_CLK_CFG_SRC, clk_cfg) != 0;
+			val = state->period * (use_bus_clk ? bus_rate : hosc_rate);
+			do_div(val, NSEC_PER_SEC);
+
+			div_m = FIELD_GET(PWM_CLK_CFG_DIV_M, clk_cfg);
+		} else {
+			/* check period and select clock source */
+			use_bus_clk = false;
+			val = state->period * hosc_rate;
+			do_div(val, NSEC_PER_SEC);
+			if (val <= 1) {
+				use_bus_clk = true;
+				val = state->period * bus_rate;
+				do_div(val, NSEC_PER_SEC);
+				if (val <= 1) {
+					ret = -EINVAL;
+					goto unlock_mutex;
+				}
+			}
+			div_m = fls(DIV_ROUND_DOWN_ULL(val, PWM_MAGIC));
+			if (div_m >= 9) {
+				ret = -EINVAL;
+				goto unlock_mutex;
+			}
+
+			/* set up the CLK_DIV_M and clock CLK_SRC */
+			clk_cfg = FIELD_PREP(PWM_CLK_CFG_DIV_M, div_m);
+			clk_cfg |= FIELD_PREP(PWM_CLK_CFG_SRC, use_bus_clk);
+
+			sun20i_pwm_writel(sun20i_chip, clk_cfg, PWM_CLK_CFG(pwm->hwpwm));
+		}
+
+		/* calculate prescaler, PWM entire cycle */
+		clk_div = val >> div_m;
+		if (clk_div <= 65534) {
+			prescaler = 0;
+		} else {
+			prescaler = DIV_ROUND_UP_ULL(clk_div - 65534, 65535);
+			if (prescaler >= 256) {
+				ret = -EINVAL;
+				goto unlock_mutex;
+			}
+			do_div(clk_div, prescaler + 1);
+		}
+
+		period = FIELD_PREP(PWM_PERIOD_ENTIRE_CYCLE, clk_div);
+
+		/* set duty cycle */
+		val = state->duty_cycle * (use_bus_clk ? bus_rate : hosc_rate);
+		do_div(val, NSEC_PER_SEC);
+		clk_div = val >> div_m;
+		do_div(clk_div, prescaler + 1);
+
+		/*
+		 * The formula of the output period and the duty-cycle for PWM are as follows.
+		 * T period = (PWM01_CLK / PWM0_PRESCALE_K)^-1 * (PPR0.PWM_ENTIRE_CYCLE + 1)
+		 * T high-level = (PWM01_CLK / PWM0_PRESCALE_K)^-1 * PPR0.PWM_ACT_CYCLE
+		 * Duty-cycle = T high-level / T period
+		 * In accordance with this formula, in order to set the duty-cycle to 100%,
+		 * it is necessary that PWM_ACT_CYCLE >= PWM_ENTIRE_CYCLE + 1
+		 */
+		if (state->duty_cycle == state->period)
+			clk_div++;
+		period |= FIELD_PREP(PWM_PERIOD_ACT_CYCLE, clk_div);
+		sun20i_pwm_writel(sun20i_chip, period, PWM_PERIOD(pwm->hwpwm));
+
+		ctl = FIELD_PREP(PWM_CTL_PRESCAL_K, prescaler);
+		if (state->polarity == PWM_POLARITY_NORMAL)
+			ctl |= PWM_CTL_ACT_STA;
+
+		sun20i_pwm_writel(sun20i_chip, ctl, PWM_CTL(pwm->hwpwm));
+	}
+
+	if (state->enabled != pwm->state.enabled && state->enabled) {
+		clk_gate &= ~PWM_CLK_GATE_BYPASS(pwm->hwpwm);
+		clk_gate |= PWM_CLK_GATE_GATING(pwm->hwpwm);
+		pwm_en |= PWM_ENABLE_EN(pwm->hwpwm);
+		sun20i_pwm_writel(sun20i_chip, pwm_en, PWM_ENABLE);
+		sun20i_pwm_writel(sun20i_chip, clk_gate, PWM_CLK_GATE);
+	}
+
+unlock_mutex:
+	mutex_unlock(&sun20i_chip->mutex);
+
+	return ret;
+}
+
+static const struct pwm_ops sun20i_pwm_ops = {
+	.get_state = sun20i_pwm_get_state,
+	.apply = sun20i_pwm_apply,
+	.owner = THIS_MODULE,
+};
+
+static const struct of_device_id sun20i_pwm_dt_ids[] = {
+	{ .compatible = "allwinner,sun20i-d1-pwm" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, sun20i_pwm_dt_ids);
+
+static int sun20i_pwm_probe(struct platform_device *pdev)
+{
+	struct sun20i_pwm_chip *sun20i_chip;
+	int ret;
+
+	sun20i_chip = devm_kzalloc(&pdev->dev, sizeof(*sun20i_chip), GFP_KERNEL);
+	if (!sun20i_chip)
+		return -ENOMEM;
+
+	sun20i_chip->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(sun20i_chip->base))
+		return PTR_ERR(sun20i_chip->base);
+
+	sun20i_chip->clk_bus = devm_clk_get_enabled(&pdev->dev, "bus");
+	if (IS_ERR(sun20i_chip->clk_bus))
+		return dev_err_probe(&pdev->dev, PTR_ERR(sun20i_chip->clk_bus),
+				     "failed to get bus clock\n");
+
+	sun20i_chip->clk_hosc = devm_clk_get_enabled(&pdev->dev, "hosc");
+	if (IS_ERR(sun20i_chip->clk_hosc))
+		return dev_err_probe(&pdev->dev, PTR_ERR(sun20i_chip->clk_hosc),
+				     "failed to get hosc clock\n");
+
+	sun20i_chip->rst = devm_reset_control_get_exclusive(&pdev->dev, NULL);
+	if (IS_ERR(sun20i_chip->rst))
+		return dev_err_probe(&pdev->dev, PTR_ERR(sun20i_chip->rst),
+				     "failed to get bus reset\n");
+
+	ret = of_property_read_u32(pdev->dev.of_node, "allwinner,pwm-channels",
+				   &sun20i_chip->chip.npwm);
+	if (ret)
+		sun20i_chip->chip.npwm = 8;
+
+	/* Deassert reset */
+	ret = reset_control_deassert(sun20i_chip->rst);
+	if (ret)
+		return dev_err_probe(&pdev->dev, ret, "failed to deassert reset\n");
+
+	sun20i_chip->chip.dev = &pdev->dev;
+	sun20i_chip->chip.ops = &sun20i_pwm_ops;
+
+	mutex_init(&sun20i_chip->mutex);
+
+	ret = pwmchip_add(&sun20i_chip->chip);
+	if (ret < 0) {
+		reset_control_assert(sun20i_chip->rst);
+		return dev_err_probe(&pdev->dev, ret, "failed to add PWM chip\n");
+	}
+
+	platform_set_drvdata(pdev, sun20i_chip);
+
+	return 0;
+}
+
+static void sun20i_pwm_remove(struct platform_device *pdev)
+{
+	struct sun20i_pwm_chip *sun20i_chip = platform_get_drvdata(pdev);
+
+	pwmchip_remove(&sun20i_chip->chip);
+
+	reset_control_assert(sun20i_chip->rst);
+}
+
+static struct platform_driver sun20i_pwm_driver = {
+	.driver = {
+		.name = "sun20i-pwm",
+		.of_match_table = sun20i_pwm_dt_ids,
+	},
+	.probe = sun20i_pwm_probe,
+	.remove_new = sun20i_pwm_remove,
+};
+module_platform_driver(sun20i_pwm_driver);
+
+MODULE_AUTHOR("Aleksandr Shubin <privatesub2@gmail.com>");
+MODULE_DESCRIPTION("Allwinner sun20i PWM driver");
+MODULE_LICENSE("GPL");
-- 
2.25.1

[PATCH v4 3/3] riscv: dts: allwinner: d1: Add pwm node

[Aleksandr Shubin]

D1 and T113s contain a pwm controller with 8 channels.
This controller is supported by the sun20i-pwm driver.

Add a device tree node for it.

Signed-off-by: Aleksandr Shubin <privatesub2@gmail.com>
---
 arch/riscv/boot/dts/allwinner/sunxi-d1s-t113.dtsi | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/arch/riscv/boot/dts/allwinner/sunxi-d1s-t113.dtsi b/arch/riscv/boot/dts/allwinner/sunxi-d1s-t113.dtsi
index 922e8e0e2c09..e24543b6aff7 100644
--- a/arch/riscv/boot/dts/allwinner/sunxi-d1s-t113.dtsi
+++ b/arch/riscv/boot/dts/allwinner/sunxi-d1s-t113.dtsi
@@ -127,6 +127,17 @@ uart3_pb_pins: uart3-pb-pins {
 			};
 		};
 
+		pwm: pwm@2000c00 {
+			compatible = "allwinner,sun20i-d1-pwm";
+			reg = <0x02000c00 0x400>;
+			clocks = <&dcxo>,
+				 <&ccu CLK_BUS_PWM>;
+			clock-names = "hosc", "bus";
+			resets = <&ccu RST_BUS_PWM>;
+			status = "disabled";
+			#pwm-cells = <0x3>;
+		};
+
 		ccu: clock-controller@2001000 {
 			compatible = "allwinner,sun20i-d1-ccu";
 			reg = <0x2001000 0x1000>;
-- 
2.25.1

Re: [PATCH v4 1/3] dt-bindings: pwm: Add binding for Allwinner D1/T113-S3/R329 PWM controller

[Conor Dooley]

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On Thu, Aug 10, 2023 at 05:54:26PM +0300, Aleksandr Shubin wrote:

> +allOf:
> +  - $ref: pwm.yaml#
> +
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            const: allwinner,sun20i-r329-pwm
> +
> +    then:
> +      required:
> +        - allwinner,pwm-channels
> +
> +    else:
> +      not:
> +        required:
> +          - allwinner,pwm-channels

Hmm, I realise I lead you astray a little. This can be reduced to
    else:
      properties:
        allwinner,pwm-channels: false

If you respin, please update to that. Otherwise,
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>

Thanks,
Conor.

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Re: [PATCH v4 1/3] dt-bindings: pwm: Add binding for Allwinner D1/T113-S3/R329 PWM controller

[Rob Herring]

On Thu, 10 Aug 2023 17:54:26 +0300, Aleksandr Shubin wrote:
> Allwinner's D1, T113-S3 and R329 SoCs have a new pwm
> controller witch is different from the previous pwm-sun4i.
> 
> The D1 and T113 are identical in terms of peripherals,
> they differ only in the architecture of the CPU core, and
> even share the majority of their DT. Because of that,
> using the same compatible makes sense.
> The R329 is a different SoC though, and should have
> a different compatible string added, especially as there
> is a difference in the number of channels.
> 
> D1 and T113s SoCs have one PWM controller with 8 channels.
> R329 SoC has two PWM controllers in both power domains, one of
> them has 9 channels (CPUX one) and the other has 6 (CPUS one).
> 
> Add a device tree binding for them.
> 
> Signed-off-by: Aleksandr Shubin <privatesub2@gmail.com>
> ---
>  .../bindings/pwm/allwinner,sun20i-pwm.yaml    | 86 +++++++++++++++++++
>  1 file changed, 86 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/pwm/allwinner,sun20i-pwm.yaml
> 

My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check'
on your patch (DT_CHECKER_FLAGS is new in v5.13):

yamllint warnings/errors:

dtschema/dtc warnings/errors:


doc reference errors (make refcheckdocs):

See https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20230810145443.1053387-2-privatesub2@gmail.com

The base for the series is generally the latest rc1. A different dependency
should be noted in *this* patch.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit after running the above command yourself. Note
that DT_SCHEMA_FILES can be set to your schema file to speed up checking
your schema. However, it must be unset to test all examples with your schema.

Re: [PATCH v4 1/3] dt-bindings: pwm: Add binding for Allwinner D1/T113-S3/R329 PWM controller

[Rob Herring]

On Thu, Aug 10, 2023 at 10:21:30AM -0600, Rob Herring wrote:
> 
> On Thu, 10 Aug 2023 17:54:26 +0300, Aleksandr Shubin wrote:
> > Allwinner's D1, T113-S3 and R329 SoCs have a new pwm
> > controller witch is different from the previous pwm-sun4i.
> > 
> > The D1 and T113 are identical in terms of peripherals,
> > they differ only in the architecture of the CPU core, and
> > even share the majority of their DT. Because of that,
> > using the same compatible makes sense.
> > The R329 is a different SoC though, and should have
> > a different compatible string added, especially as there
> > is a difference in the number of channels.
> > 
> > D1 and T113s SoCs have one PWM controller with 8 channels.
> > R329 SoC has two PWM controllers in both power domains, one of
> > them has 9 channels (CPUX one) and the other has 6 (CPUS one).
> > 
> > Add a device tree binding for them.
> > 
> > Signed-off-by: Aleksandr Shubin <privatesub2@gmail.com>
> > ---
> >  .../bindings/pwm/allwinner,sun20i-pwm.yaml    | 86 +++++++++++++++++++
> >  1 file changed, 86 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/pwm/allwinner,sun20i-pwm.yaml
> > 
> 
> My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check'
> on your patch (DT_CHECKER_FLAGS is new in v5.13):
> 
> yamllint warnings/errors:
> 
> dtschema/dtc warnings/errors:
> 
> 
> doc reference errors (make refcheckdocs):
> 
> See https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20230810145443.1053387-2-privatesub2@gmail.com

The bot was having an issue. This can be ignored.

Rob

Re: [PATCH v4 2/3] pwm: Add Allwinner's D1/T113-S3/R329 SoCs PWM support

[kernel test robot]

Hi Aleksandr,

kernel test robot noticed the following build warnings:

[auto build test WARNING on thierry-reding-pwm/for-next]
[also build test WARNING on sunxi/sunxi/for-next robh/for-next linus/master v6.5-rc5 next-20230809]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Aleksandr-Shubin/dt-bindings-pwm-Add-binding-for-Allwinner-D1-T113-S3-R329-PWM-controller/20230810-225849
base:   https://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm.git for-next
patch link:    https://lore.kernel.org/r/20230810145443.1053387-3-privatesub2%40gmail.com
patch subject: [PATCH v4 2/3] pwm: Add Allwinner's D1/T113-S3/R329 SoCs PWM support
config: x86_64-allyesconfig (https://download.01.org/0day-ci/archive/20230812/202308122212.SOHP09RP-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce: (https://download.01.org/0day-ci/archive/20230812/202308122212.SOHP09RP-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202308122212.SOHP09RP-lkp@intel.com/

All warnings (new ones prefixed by >>):

   drivers/pwm/pwm-sun20i.c: In function 'sun20i_pwm_apply':
>> drivers/pwm/pwm-sun20i.c:121:48: warning: unused variable 'tmp' [-Wunused-variable]
     121 |         u64 bus_rate, hosc_rate, clk_div, val, tmp;
         |                                                ^~~


vim +/tmp +121 drivers/pwm/pwm-sun20i.c

   115	
   116	static int sun20i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
   117				    const struct pwm_state *state)
   118	{
   119		struct sun20i_pwm_chip *sun20i_chip = to_sun20i_pwm_chip(chip);
   120		u32 clk_gate, clk_cfg, pwm_en, ctl, period;
 > 121		u64 bus_rate, hosc_rate, clk_div, val, tmp;
   122		u32 prescaler, div_m;
   123		bool use_bus_clk;
   124		int ret = 0;
   125	
   126		mutex_lock(&sun20i_chip->mutex);
   127	
   128		pwm_en = sun20i_pwm_readl(sun20i_chip, PWM_ENABLE);
   129	
   130		if (state->enabled != pwm->state.enabled)
   131			clk_gate = sun20i_pwm_readl(sun20i_chip, PWM_CLK_GATE);
   132	
   133		if (state->enabled != pwm->state.enabled && !state->enabled) {
   134			clk_gate &= ~PWM_CLK_GATE_GATING(pwm->hwpwm);
   135			pwm_en &= ~PWM_ENABLE_EN(pwm->hwpwm);
   136			sun20i_pwm_writel(sun20i_chip, pwm_en, PWM_ENABLE);
   137			sun20i_pwm_writel(sun20i_chip, clk_gate, PWM_CLK_GATE);
   138		}
   139	
   140		if (state->polarity != pwm->state.polarity ||
   141		    state->duty_cycle != pwm->state.duty_cycle ||
   142		    state->period != pwm->state.period) {
   143			ctl = sun20i_pwm_readl(sun20i_chip, PWM_CTL(pwm->hwpwm));
   144			clk_cfg = sun20i_pwm_readl(sun20i_chip, PWM_CLK_CFG(pwm->hwpwm));
   145			hosc_rate = clk_get_rate(sun20i_chip->clk_hosc);
   146			bus_rate = clk_get_rate(sun20i_chip->clk_bus);
   147			if (pwm_en & PWM_ENABLE_EN(pwm->hwpwm ^ 1)) {
   148				/* if the neighbor channel is enable, check period only */
   149				use_bus_clk = FIELD_GET(PWM_CLK_CFG_SRC, clk_cfg) != 0;
   150				val = state->period * (use_bus_clk ? bus_rate : hosc_rate);
   151				do_div(val, NSEC_PER_SEC);
   152	
   153				div_m = FIELD_GET(PWM_CLK_CFG_DIV_M, clk_cfg);
   154			} else {
   155				/* check period and select clock source */
   156				use_bus_clk = false;
   157				val = state->period * hosc_rate;
   158				do_div(val, NSEC_PER_SEC);
   159				if (val <= 1) {
   160					use_bus_clk = true;
   161					val = state->period * bus_rate;
   162					do_div(val, NSEC_PER_SEC);
   163					if (val <= 1) {
   164						ret = -EINVAL;
   165						goto unlock_mutex;
   166					}
   167				}
   168				div_m = fls(DIV_ROUND_DOWN_ULL(val, PWM_MAGIC));
   169				if (div_m >= 9) {
   170					ret = -EINVAL;
   171					goto unlock_mutex;
   172				}
   173	
   174				/* set up the CLK_DIV_M and clock CLK_SRC */
   175				clk_cfg = FIELD_PREP(PWM_CLK_CFG_DIV_M, div_m);
   176				clk_cfg |= FIELD_PREP(PWM_CLK_CFG_SRC, use_bus_clk);
   177	
   178				sun20i_pwm_writel(sun20i_chip, clk_cfg, PWM_CLK_CFG(pwm->hwpwm));
   179			}
   180	
   181			/* calculate prescaler, PWM entire cycle */
   182			clk_div = val >> div_m;
   183			if (clk_div <= 65534) {
   184				prescaler = 0;
   185			} else {
   186				prescaler = DIV_ROUND_UP_ULL(clk_div - 65534, 65535);
   187				if (prescaler >= 256) {
   188					ret = -EINVAL;
   189					goto unlock_mutex;
   190				}
   191				do_div(clk_div, prescaler + 1);
   192			}
   193	
   194			period = FIELD_PREP(PWM_PERIOD_ENTIRE_CYCLE, clk_div);
   195	
   196			/* set duty cycle */
   197			val = state->duty_cycle * (use_bus_clk ? bus_rate : hosc_rate);
   198			do_div(val, NSEC_PER_SEC);
   199			clk_div = val >> div_m;
   200			do_div(clk_div, prescaler + 1);
   201	
   202			/*
   203			 * The formula of the output period and the duty-cycle for PWM are as follows.
   204			 * T period = (PWM01_CLK / PWM0_PRESCALE_K)^-1 * (PPR0.PWM_ENTIRE_CYCLE + 1)
   205			 * T high-level = (PWM01_CLK / PWM0_PRESCALE_K)^-1 * PPR0.PWM_ACT_CYCLE
   206			 * Duty-cycle = T high-level / T period
   207			 * In accordance with this formula, in order to set the duty-cycle to 100%,
   208			 * it is necessary that PWM_ACT_CYCLE >= PWM_ENTIRE_CYCLE + 1
   209			 */
   210			if (state->duty_cycle == state->period)
   211				clk_div++;
   212			period |= FIELD_PREP(PWM_PERIOD_ACT_CYCLE, clk_div);
   213			sun20i_pwm_writel(sun20i_chip, period, PWM_PERIOD(pwm->hwpwm));
   214	
   215			ctl = FIELD_PREP(PWM_CTL_PRESCAL_K, prescaler);
   216			if (state->polarity == PWM_POLARITY_NORMAL)
   217				ctl |= PWM_CTL_ACT_STA;
   218	
   219			sun20i_pwm_writel(sun20i_chip, ctl, PWM_CTL(pwm->hwpwm));
   220		}
   221	
   222		if (state->enabled != pwm->state.enabled && state->enabled) {
   223			clk_gate &= ~PWM_CLK_GATE_BYPASS(pwm->hwpwm);
   224			clk_gate |= PWM_CLK_GATE_GATING(pwm->hwpwm);
   225			pwm_en |= PWM_ENABLE_EN(pwm->hwpwm);
   226			sun20i_pwm_writel(sun20i_chip, pwm_en, PWM_ENABLE);
   227			sun20i_pwm_writel(sun20i_chip, clk_gate, PWM_CLK_GATE);
   228		}
   229	
   230	unlock_mutex:
   231		mutex_unlock(&sun20i_chip->mutex);
   232	
   233		return ret;
   234	}
   235	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki