[PATCH v4 0/4] Microchip soft ip corePWM driver

[PATCH v4 0/4] Microchip soft ip corePWM driver

[Conor Dooley]

Hey Uwe, all,

Added some extra patches so I have a cover letter this time.
You pointed out that I was overriding npwmcells in the driver and I 
realised that the dt & binding were not correct so I have added two
simple patches to deal with that. The dts patch I will take in my tree
once the binding is applied.

For the maintainers entry, I mentioned before that I have several
changes in-flight for it. We are late(ish) in the cycle so I doubt
you'll be applying this for v5.20, but in the off chance you do - I
would be happy to send it (with your Ack) alongside an i2c addition
that is "deferred".

In your review of v3, you had a lot of comments about the period and
duty cycle calculations, so I have had another run at them. I converted
the period calculation to "search" from the bottom up for the suitable
prescale value. The duty cycle calculation has been fixed - the problem
was exactly what I suspected in my replies to your review. I had to block
the use of a 0xFF period_steps register value (which I think should be
covered by the updated comment and limitation #2).

Beyond that, I have rebased on -next and converted to the devm_ stuff
in probe that was recently added & dropped remove() - as requested.
I added locking to protect the period racing, changed the #defines and
switched to returning -EINVAL when the period is locked to a value
greater than that requested.

Thanks,
Conor.

Conor Dooley (4):
  dt-bindings: pwm: fix microchip corePWM's pwm-cells
  riscv: dts: fix the icicle's #pwm-cells
  pwm: add microchip soft ip corePWM driver
  MAINTAINERS: add pwm to PolarFire SoC entry

 .../bindings/pwm/microchip,corepwm.yaml       |   4 +-
 MAINTAINERS                                   |   1 +
 .../dts/microchip/mpfs-icicle-kit-fabric.dtsi |   2 +-
 .../dts/microchip/mpfs-tysom-m-fabric.dtsi    |  18 +
 .../riscv/boot/dts/microchip/mpfs-tysom-m.dts | 185 +++++++++
 drivers/pwm/Kconfig                           |  10 +
 drivers/pwm/Makefile                          |   1 +
 drivers/pwm/pwm-microchip-core.c              | 355 ++++++++++++++++++
 8 files changed, 574 insertions(+), 2 deletions(-)
 create mode 100644 arch/riscv/boot/dts/microchip/mpfs-tysom-m-fabric.dtsi
 create mode 100644 arch/riscv/boot/dts/microchip/mpfs-tysom-m.dts
 create mode 100644 drivers/pwm/pwm-microchip-core.c


base-commit: 088b9c375534d905a4d337c78db3b3bfbb52c4a0
-- 
2.36.1

[PATCH v4 1/4] dt-bindings: pwm: fix microchip corePWM's pwm-cells

[Conor Dooley]

corePWM is capable of inverted operation but the binding requires
\#pwm-cells of 2. Expand the binding to support setting the polarity.

Fixes: df77f7735786 ("dt-bindings: pwm: add microchip corepwm binding")
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
---
 Documentation/devicetree/bindings/pwm/microchip,corepwm.yaml | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/pwm/microchip,corepwm.yaml b/Documentation/devicetree/bindings/pwm/microchip,corepwm.yaml
index a7fae1772a81..cd8e9a8907f8 100644
--- a/Documentation/devicetree/bindings/pwm/microchip,corepwm.yaml
+++ b/Documentation/devicetree/bindings/pwm/microchip,corepwm.yaml
@@ -30,7 +30,9 @@ properties:
     maxItems: 1
 
   "#pwm-cells":
-    const: 2
+    enum: [2, 3]
+    description:
+      The only flag supported by the controller is PWM_POLARITY_INVERTED.
 
   microchip,sync-update-mask:
     description: |
-- 
2.36.1

[PATCH v4 2/4] riscv: dts: fix the icicle's #pwm-cells

[Conor Dooley]

\#pwm-cells for the Icicle kit's fabric PWM was incorrectly set to 2 &
blindly overridden by the (out of tree) driver anyway. The core can
support inverted operation, so update the entry to correctly report its
capabilities.

Fixes: 72560c6559b8 ("riscv: dts: microchip: add fpga fabric section to icicle kit")
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
---
 .../dts/microchip/mpfs-icicle-kit-fabric.dtsi |   2 +-
 .../dts/microchip/mpfs-tysom-m-fabric.dtsi    |  18 ++
 .../riscv/boot/dts/microchip/mpfs-tysom-m.dts | 185 ++++++++++++++++++
 3 files changed, 204 insertions(+), 1 deletion(-)
 create mode 100644 arch/riscv/boot/dts/microchip/mpfs-tysom-m-fabric.dtsi
 create mode 100644 arch/riscv/boot/dts/microchip/mpfs-tysom-m.dts

diff --git a/arch/riscv/boot/dts/microchip/mpfs-icicle-kit-fabric.dtsi b/arch/riscv/boot/dts/microchip/mpfs-icicle-kit-fabric.dtsi
index 0d28858b83f2..e09a13aef268 100644
--- a/arch/riscv/boot/dts/microchip/mpfs-icicle-kit-fabric.dtsi
+++ b/arch/riscv/boot/dts/microchip/mpfs-icicle-kit-fabric.dtsi
@@ -8,7 +8,7 @@ core_pwm0: pwm@41000000 {
 		compatible = "microchip,corepwm-rtl-v4";
 		reg = <0x0 0x41000000 0x0 0xF0>;
 		microchip,sync-update-mask = /bits/ 32 <0>;
-		#pwm-cells = <2>;
+		#pwm-cells = <3>;
 		clocks = <&fabric_clk3>;
 		status = "disabled";
 	};
diff --git a/arch/riscv/boot/dts/microchip/mpfs-tysom-m-fabric.dtsi b/arch/riscv/boot/dts/microchip/mpfs-tysom-m-fabric.dtsi
new file mode 100644
index 000000000000..98f642e83ad4
--- /dev/null
+++ b/arch/riscv/boot/dts/microchip/mpfs-tysom-m-fabric.dtsi
@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/* Copyright (c) 2022 Microchip Technology Inc */
+
+// #include "dt-bindings/mailbox/miv-ihc.h"
+
+/ {
+	fabric_clk3: fabric-clk3 {
+		compatible = "fixed-clock";
+		#clock-cells = <0>;
+		clock-frequency = <62500000>;
+	};
+
+	fabric_clk1: fabric-clk1 {
+		compatible = "fixed-clock";
+		#clock-cells = <0>;
+		clock-frequency = <125000000>;
+	};
+};
diff --git a/arch/riscv/boot/dts/microchip/mpfs-tysom-m.dts b/arch/riscv/boot/dts/microchip/mpfs-tysom-m.dts
new file mode 100644
index 000000000000..0b664c591255
--- /dev/null
+++ b/arch/riscv/boot/dts/microchip/mpfs-tysom-m.dts
@@ -0,0 +1,185 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Original all-in-one devicetree:
+ * Copyright (C) 2020-2022 - Aldec
+ * Rewritten to use includes:
+ * Copyright (C) 2022 - Conor Dooley <conor.dooley@microchip.com>
+ */
+
+/dts-v1/;
+
+#include "mpfs.dtsi"
+#include "mpfs-tysom-m-fabric.dtsi"
+
+/* Clock frequency (in Hz) of the rtcclk */
+#define MTIMER_FREQ		1000000
+
+/ {
+	model = "Aldec TySOM-M-MPFS250T";
+	compatible = "aldec,tysom-m-mpfs250t", "microchip,mpfs";
+
+	aliases {
+		ethernet0 = &mac0;
+		ethernet1 = &mac1;
+		serial0 = &mmuart0;
+		serial1 = &mmuart1;
+		serial2 = &mmuart2;
+		serial3 = &mmuart3;
+		serial4 = &mmuart4;
+		gpio0 = &gpio0;
+		gpio1 = &gpio2;
+	};
+
+	chosen {
+		stdout-path = "serial1:115200n8";
+	};
+
+	cpus {
+		timebase-frequency = <MTIMER_FREQ>;
+	};
+
+	ddrc_cache_lo: memory@80000000 {
+		device_type = "memory";
+		reg = <0x0 0x80000000 0x0 0x2e000000>;
+		status = "okay";
+	};
+
+	ddrc_cache_hi: memory@1000000000 {
+		device_type = "memory";
+		reg = <0x10 0x00000000 0x0 0x40000000>;
+		status = "okay";
+	};
+
+	soc {
+	};
+
+	leds {
+		compatible = "gpio-leds";
+		status = "okay";
+
+		led0 {
+			gpios = <&gpio1 23 1>;
+			default-state = "on";
+			linux,default-trigger = "heartbeat";
+		};
+	};
+};
+
+&i2c0 {
+	status = "okay";
+};
+
+&i2c1 {
+	status = "okay";
+	ina219: ina219@45 {
+		status = "okay";
+		compatible = "ti,ina219";
+		reg = <0x45>;
+		shunt-resistor = <0x7d0>;
+	};
+};
+
+&gpio1 {
+	interrupts = <27 28 29 30 31 32 33 47 35 36 37 38 39 40 41 42 43 44 45 46 34 48 49 50>;
+	status = "okay";
+};
+
+&mac0 {
+	status = "okay";
+	phy-mode = "gmii";
+	phy-handle = <&phy0>;
+
+};
+
+&mac1 {
+	status = "okay";
+	phy-mode = "gmii";
+	phy-handle = <&phy1>;
+	phy1: ethernet-phy@1 {
+		reg = <1>;
+		ti,fifo-depth = <0x01>;
+	};
+	phy0: ethernet-phy@0 {
+		reg = <0>;
+		ti,fifo-depth = <0x01>;
+	};
+};
+
+&mbox {
+	status = "okay";
+};
+
+&mmc {
+	max-frequency = <200000000>;
+	cap-mmc-highspeed;
+	cap-sd-highspeed;
+	no-1-8-v;
+	disable-wp;
+	status = "okay";
+};
+
+&mmuart1 {
+	status = "okay";
+};
+
+&mmuart2 {
+	status = "okay";
+};
+
+&mmuart3 {
+	status = "okay";
+};
+
+&mmuart4 {
+	status = "okay";
+};
+
+&refclk {
+	clock-frequency = <125000000>;
+};
+
+&rtc {
+	status = "okay";
+};
+
+&spi0 {
+	status = "okay";
+};
+
+&spi1 {
+	status = "okay";
+	pseFlash@0 {
+		#address-cells = <1>;
+		#size-cells = <1>;
+		compatible = "n25q128a11", "jedec,spi-nor";
+		status = "okay";
+		reg = <0x0>;
+		spi-max-frequency = <10000000>;
+
+		partition@test-0 { /* test purposes */
+			label = "qspi-test-0";
+			reg = <0x00000000 0x00800000>;
+		};
+		partition@test-1 { /* test purposes */
+			label = "qspi-test-1";
+			reg = <0x00800000 0x00800000>;
+		};
+		partition@test-2 { /* test purposes */
+			label = "qspi-test-2";
+			reg = <0x01000000 0x00800000>;
+		};
+		partition@test-3 { /* test purposes */
+			label = "qspi-test-3";
+			reg = <0x01800000 0x00800000>;
+		};
+	};
+};
+
+&syscontroller {
+	status = "okay";
+};
+
+&usb {
+	status = "okay";
+	dr_mode = "host";
+};
-- 
2.36.1

[PATCH v4 3/4] pwm: add microchip soft ip corePWM driver

[Conor Dooley]

Add a driver that supports the Microchip FPGA "soft" PWM IP core.

Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
---
 drivers/pwm/Kconfig              |  10 +
 drivers/pwm/Makefile             |   1 +
 drivers/pwm/pwm-microchip-core.c | 355 +++++++++++++++++++++++++++++++
 3 files changed, 366 insertions(+)
 create mode 100644 drivers/pwm/pwm-microchip-core.c

diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index 904de8d61828..007ea5750e73 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -383,6 +383,16 @@ config PWM_MEDIATEK
 	  To compile this driver as a module, choose M here: the module
 	  will be called pwm-mediatek.
 
+config PWM_MICROCHIP_CORE
+	tristate "Microchip corePWM PWM support"
+	depends on SOC_MICROCHIP_POLARFIRE || COMPILE_TEST
+	depends on HAS_IOMEM && OF
+	help
+	  PWM driver for Microchip FPGA soft IP core.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-microchip-core.
+
 config PWM_MXS
 	tristate "Freescale MXS PWM support"
 	depends on ARCH_MXS || COMPILE_TEST
diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile
index 5c08bdb817b4..43feb7cfc66a 100644
--- a/drivers/pwm/Makefile
+++ b/drivers/pwm/Makefile
@@ -33,6 +33,7 @@ obj-$(CONFIG_PWM_LPSS_PCI)	+= pwm-lpss-pci.o
 obj-$(CONFIG_PWM_LPSS_PLATFORM)	+= pwm-lpss-platform.o
 obj-$(CONFIG_PWM_MESON)		+= pwm-meson.o
 obj-$(CONFIG_PWM_MEDIATEK)	+= pwm-mediatek.o
+obj-$(CONFIG_PWM_MICROCHIP_CORE)	+= pwm-microchip-core.o
 obj-$(CONFIG_PWM_MTK_DISP)	+= pwm-mtk-disp.o
 obj-$(CONFIG_PWM_MXS)		+= pwm-mxs.o
 obj-$(CONFIG_PWM_NTXEC)		+= pwm-ntxec.o
diff --git a/drivers/pwm/pwm-microchip-core.c b/drivers/pwm/pwm-microchip-core.c
new file mode 100644
index 000000000000..3471eb2c8645
--- /dev/null
+++ b/drivers/pwm/pwm-microchip-core.c
@@ -0,0 +1,355 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * corePWM driver for Microchip "soft" FPGA IP cores.
+ *
+ * Copyright (c) 2021-2022 Microchip Corporation. All rights reserved.
+ * Author: Conor Dooley <conor.dooley@microchip.com>
+ * Documentation:
+ * https://www.microsemi.com/document-portal/doc_download/1245275-corepwm-hb
+ *
+ * Limitations:
+ * - If the IP block is configured without "shadow registers", all register
+ *   writes will take effect immediately, causing glitches on the output.
+ *   If shadow registers *are* enabled, a write to the "SYNC_UPDATE" register
+ *   notifies the core that it needs to update the registers defining the
+ *   waveform from the contents of the "shadow registers".
+ * - The IP block has no concept of a duty cycle, only rising/falling edges of
+ *   the waveform. Unfortunately, if the rising & falling edges registers have
+ *   the same value written to them the IP block will do whichever of a rising
+ *   or a falling edge is possible. I.E. a 50% waveform at twice the requested
+ *   period. Therefore to get a 0% waveform, the output is set the max high/low
+ *   time depending on polarity.
+ * - The PWM period is set for the whole IP block not per channel. The driver
+ *   will only change the period if no other PWM output is enabled.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/math.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/spinlock.h>
+
+#define PREG_TO_VAL(PREG) ((PREG) + 1)
+
+#define MCHPCOREPWM_PRESCALE_MAX	0x100
+#define MCHPCOREPWM_PERIOD_STEPS_MAX	0xff
+#define MCHPCOREPWM_PERIOD_MAX		0xff00
+
+#define MCHPCOREPWM_PRESCALE	0x00
+#define MCHPCOREPWM_PERIOD	0x04
+#define MCHPCOREPWM_EN(i)	(0x08 + 0x04 * (i)) /* 0x08, 0x0c */
+#define MCHPCOREPWM_POSEDGE(i)	(0x10 + 0x08 * (i)) /* 0x10, 0x18, ..., 0x88 */
+#define MCHPCOREPWM_NEGEDGE(i)	(0x14 + 0x08 * (i)) /* 0x14, 0x1c, ..., 0x8c */
+#define MCHPCOREPWM_SYNC_UPD	0xe4
+
+struct mchp_core_pwm_chip {
+	struct pwm_chip chip;
+	struct clk *clk;
+	spinlock_t lock; /* protect the shared period */
+	void __iomem *base;
+	u32 sync_update_mask;
+};
+
+static inline struct mchp_core_pwm_chip *to_mchp_core_pwm(struct pwm_chip *chip)
+{
+	return container_of(chip, struct mchp_core_pwm_chip, chip);
+}
+
+static void mchp_core_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm, bool enable)
+{
+	struct mchp_core_pwm_chip *mchp_core_pwm = to_mchp_core_pwm(chip);
+	u8 channel_enable, reg_offset, shift;
+
+	/*
+	 * There are two adjacent 8 bit control regs, the lower reg controls
+	 * 0-7 and the upper reg 8-15. Check if the pwm is in the upper reg
+	 * and if so, offset by the bus width.
+	 */
+	reg_offset = MCHPCOREPWM_EN(pwm->hwpwm >> 3);
+	shift = pwm->hwpwm > 7 ? pwm->hwpwm - 8 : pwm->hwpwm;
+
+	spin_lock(&mchp_core_pwm->lock);
+
+	channel_enable = readb_relaxed(mchp_core_pwm->base + reg_offset);
+	channel_enable &= ~(1 << shift);
+	channel_enable |= (enable << shift);
+
+	writel_relaxed(channel_enable, mchp_core_pwm->base + reg_offset);
+
+	/*
+	 * Write to the sync update registers so that channels with shadow
+	 * registers will also get their enable update. This operation is a NOP
+	 * for channels without shadow registers.
+	 */
+	writel_relaxed(1U, mchp_core_pwm->base + MCHPCOREPWM_SYNC_UPD);
+
+	spin_unlock(&mchp_core_pwm->lock);
+}
+
+static void mchp_core_pwm_apply_duty(struct pwm_chip *chip, struct pwm_device *pwm,
+				     const struct pwm_state *state, u8 prescale, u8 period_steps)
+{
+	struct mchp_core_pwm_chip *mchp_core_pwm = to_mchp_core_pwm(chip);
+	u64 duty_steps, period, tmp;
+	u8 posedge, negedge;
+	u16 prescale_val = PREG_TO_VAL(prescale);
+	u8 period_steps_val = PREG_TO_VAL(period_steps);
+
+	period = period_steps_val * prescale_val * NSEC_PER_SEC;
+	period = DIV64_U64_ROUND_UP(period, clk_get_rate(mchp_core_pwm->clk));
+
+	/*
+	 * Calculate the duty cycle in multiples of the prescaled period:
+	 * duty_steps = duty_in_ns / step_in_ns
+	 * step_in_ns = (prescale * NSEC_PER_SEC) / clk_rate
+	 * The code below is rearranged slightly to only divide once.
+	 *
+	 * Because the period is per channel, it is possible that the requested
+	 * duty cycle is longer than the period, in which case cap it to the
+	 * period.
+	 */
+	if (state->duty_cycle > period) {
+		duty_steps = period_steps_val;
+	} else {
+		duty_steps = state->duty_cycle * clk_get_rate(mchp_core_pwm->clk);
+		tmp = prescale_val * NSEC_PER_SEC;
+		duty_steps = div64_u64(duty_steps, tmp);
+	}
+
+	/*
+	 * Turn the output on unless posedge == negedge, in which case the
+	 * duty is intended to be 0, but limitations of the IP block don't
+	 * allow a zero length duty cycle - so just set the max high/low time
+	 * respectively.
+	 */
+	if (state->polarity == PWM_POLARITY_INVERSED) {
+		negedge = !duty_steps ? period_steps_val : 0u;
+		posedge = duty_steps;
+	} else {
+		posedge = !duty_steps ? period_steps_val : 0u;
+		negedge = duty_steps;
+	}
+
+	writel_relaxed(posedge, mchp_core_pwm->base + MCHPCOREPWM_POSEDGE(pwm->hwpwm));
+	writel_relaxed(negedge, mchp_core_pwm->base + MCHPCOREPWM_NEGEDGE(pwm->hwpwm));
+}
+
+static int mchp_core_pwm_apply_period(struct pwm_chip *chip, const struct pwm_state *state,
+				      u8 *prescale, u8 *period_steps)
+{
+	struct mchp_core_pwm_chip *mchp_core_pwm = to_mchp_core_pwm(chip);
+	u64 tmp, clk_rate;
+	u16 prescale_val, period_steps_val;
+
+	/*
+	 * Calculate the period cycles and prescale values.
+	 * The registers are each 8 bits wide & multiplied to compute the period
+	 * using the formula:
+	 * (clock_period) * (prescale + 1) * (period_steps + 1)
+	 * so the maximum period that can be generated is 0x10000 times the
+	 * period of the input clock.
+	 * However, due to the design of the "hardware", it is not possible to
+	 * attain a 100% duty cycle if the full range of period_steps is used.
+	 * Therefore period_steps is restricted to 0xFE and the maximum multiple
+	 * of the clock period attainable is 0xFF00.
+	 */
+	clk_rate = clk_get_rate(mchp_core_pwm->clk);
+	if (clk_rate >= NSEC_PER_SEC)
+		return -EINVAL;
+
+	tmp = mul_u64_u64_div_u64(state->period, clk_rate, NSEC_PER_SEC);
+
+	if (tmp >= MCHPCOREPWM_PERIOD_MAX) {
+		*prescale = MCHPCOREPWM_PRESCALE_MAX - 1;
+		*period_steps = MCHPCOREPWM_PERIOD_STEPS_MAX - 1;
+		goto write_registers;
+	}
+
+	for (prescale_val = 1; prescale_val <= MCHPCOREPWM_PRESCALE_MAX; prescale_val++) {
+		period_steps_val = div_u64(tmp, prescale_val);
+		if (period_steps_val > MCHPCOREPWM_PERIOD_STEPS_MAX)
+			continue;
+		*period_steps = period_steps_val - 1;
+		*prescale = prescale_val - 1;
+		break;
+	}
+
+write_registers:
+	writel_relaxed(*prescale, mchp_core_pwm->base + MCHPCOREPWM_PRESCALE);
+	writel_relaxed(*period_steps, mchp_core_pwm->base + MCHPCOREPWM_PERIOD);
+
+	return 0;
+}
+
+static int mchp_core_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+			       const struct pwm_state *state)
+{
+	struct mchp_core_pwm_chip *mchp_core_pwm = to_mchp_core_pwm(chip);
+	struct pwm_state current_state = pwm->state;
+	bool period_locked;
+	u64 period;
+	u16 channel_enabled;
+	u8 prescale, period_steps;
+	int ret;
+
+	if (!state->enabled) {
+		mchp_core_pwm_enable(chip, pwm, false);
+		return 0;
+	}
+
+	/*
+	 * If the only thing that has changed is the duty cycle or the polarity,
+	 * we can shortcut the calculations and just compute/apply the new duty
+	 * cycle pos & neg edges
+	 * As all the channels share the same period, do not allow it to be
+	 * changed if any other channels are enabled.
+	 */
+	spin_lock(&mchp_core_pwm->lock);
+
+	channel_enabled = (((u16)readb_relaxed(mchp_core_pwm->base + MCHPCOREPWM_EN(1)) << 8) |
+		readb_relaxed(mchp_core_pwm->base + MCHPCOREPWM_EN(0)));
+	period_locked = channel_enabled & ~(1 << pwm->hwpwm);
+
+	if ((!current_state.enabled || current_state.period != state->period) && !period_locked) {
+		ret = mchp_core_pwm_apply_period(chip, state, &prescale, &period_steps);
+		if (ret) {
+			spin_unlock(&mchp_core_pwm->lock);
+			return ret;
+		}
+	} else {
+		prescale = readb_relaxed(mchp_core_pwm->base + MCHPCOREPWM_PRESCALE);
+		period_steps = readb_relaxed(mchp_core_pwm->base + MCHPCOREPWM_PERIOD);
+	}
+
+	/*
+	 * If the period is locked, it may not be possible to use a period less
+	 * than that requested.
+	 */
+	period = PREG_TO_VAL(period_steps) *  PREG_TO_VAL(prescale) * NSEC_PER_SEC;
+	do_div(period, clk_get_rate(mchp_core_pwm->clk));
+	if (period > state->period) {
+		spin_unlock(&mchp_core_pwm->lock);
+		return -EINVAL;
+	}
+
+	mchp_core_pwm_apply_duty(chip, pwm, state, prescale, period_steps);
+
+	/*
+	 * Notify the block to update the waveform from the shadow registers.
+	 * The updated values will not appear on the bus until they have been
+	 * applied to the waveform at the beginning of the next period. We must
+	 * write these registers and wait for them to be applied before calling
+	 * enable().
+	 */
+	if (mchp_core_pwm->sync_update_mask & (1 << pwm->hwpwm)) {
+		writel_relaxed(1U, mchp_core_pwm->base + MCHPCOREPWM_SYNC_UPD);
+		usleep_range(state->period, state->period * 2);
+	}
+
+	spin_unlock(&mchp_core_pwm->lock);
+
+	mchp_core_pwm_enable(chip, pwm, true);
+
+	return 0;
+}
+
+static void mchp_core_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
+				    struct pwm_state *state)
+{
+	struct mchp_core_pwm_chip *mchp_core_pwm = to_mchp_core_pwm(chip);
+	u8 prescale, period_steps, duty_steps;
+	u8 posedge, negedge;
+	u16 channel_enabled;
+
+	channel_enabled = (((u16)readb_relaxed(mchp_core_pwm->base + MCHPCOREPWM_EN(1)) << 8) |
+		readb_relaxed(mchp_core_pwm->base + MCHPCOREPWM_EN(0)));
+
+	if (channel_enabled & 1 << pwm->hwpwm)
+		state->enabled = true;
+	else
+		state->enabled = false;
+
+	prescale = PREG_TO_VAL(readb_relaxed(mchp_core_pwm->base + MCHPCOREPWM_PRESCALE));
+
+	posedge = readb_relaxed(mchp_core_pwm->base + MCHPCOREPWM_POSEDGE(pwm->hwpwm));
+	negedge = readb_relaxed(mchp_core_pwm->base + MCHPCOREPWM_NEGEDGE(pwm->hwpwm));
+
+	duty_steps = abs((s16)posedge - (s16)negedge);
+	state->duty_cycle = duty_steps * prescale * NSEC_PER_SEC;
+	do_div(state->duty_cycle, clk_get_rate(mchp_core_pwm->clk));
+
+	state->polarity = negedge < posedge ? PWM_POLARITY_INVERSED : PWM_POLARITY_NORMAL;
+
+	period_steps = PREG_TO_VAL(readb_relaxed(mchp_core_pwm->base + MCHPCOREPWM_PERIOD));
+	state->period = period_steps * prescale * NSEC_PER_SEC;
+	do_div(state->period, clk_get_rate(mchp_core_pwm->clk));
+}
+
+static const struct pwm_ops mchp_core_pwm_ops = {
+	.apply = mchp_core_pwm_apply,
+	.get_state = mchp_core_pwm_get_state,
+	.owner = THIS_MODULE,
+};
+
+static const struct of_device_id mchp_core_of_match[] = {
+	{
+		.compatible = "microchip,corepwm-rtl-v4",
+	},
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mchp_core_of_match);
+
+static int mchp_core_pwm_probe(struct platform_device *pdev)
+{
+	struct mchp_core_pwm_chip *mchp_pwm;
+	struct resource *regs;
+	int ret;
+
+	mchp_pwm = devm_kzalloc(&pdev->dev, sizeof(*mchp_pwm), GFP_KERNEL);
+	if (!mchp_pwm)
+		return -ENOMEM;
+
+	mchp_pwm->base = devm_platform_get_and_ioremap_resource(pdev, 0, &regs);
+	if (IS_ERR(mchp_pwm->base))
+		return PTR_ERR(mchp_pwm->base);
+
+	mchp_pwm->clk = devm_clk_get_enabled(&pdev->dev, NULL);
+	if (IS_ERR(mchp_pwm->clk))
+		return PTR_ERR(mchp_pwm->clk);
+
+	if (of_property_read_u32(pdev->dev.of_node, "microchip,sync-update-mask",
+				 &mchp_pwm->sync_update_mask))
+		mchp_pwm->sync_update_mask = 0u;
+
+	spin_lock_init(&mchp_pwm->lock);
+
+	mchp_pwm->chip.dev = &pdev->dev;
+	mchp_pwm->chip.ops = &mchp_core_pwm_ops;
+	mchp_pwm->chip.npwm = 16;
+
+	ret = devm_pwmchip_add(&pdev->dev, &mchp_pwm->chip);
+	if (ret < 0)
+		return dev_err_probe(&pdev->dev, ret, "failed to add PWM chip\n");
+
+	platform_set_drvdata(pdev, mchp_pwm);
+
+	return 0;
+}
+
+static struct platform_driver mchp_core_pwm_driver = {
+	.driver = {
+		.name = "mchp-core-pwm",
+		.of_match_table = mchp_core_of_match,
+	},
+	.probe = mchp_core_pwm_probe,
+};
+module_platform_driver(mchp_core_pwm_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>");
+MODULE_DESCRIPTION("corePWM driver for Microchip FPGAs");
-- 
2.36.1

[PATCH v4 4/4] MAINTAINERS: add pwm to PolarFire SoC entry

[Conor Dooley]

Add the newly introduced pwm driver to the existing PolarFire SoC entry.

Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
---
 MAINTAINERS | 1 +
 1 file changed, 1 insertion(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index d64d79eb36a2..f023ae8442ab 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -17429,6 +17429,7 @@ L:	linux-riscv@lists.infradead.org
 S:	Supported
 F:	arch/riscv/boot/dts/microchip/
 F:	drivers/mailbox/mailbox-mpfs.c
+F:	drivers/pwm/pwm-microchip-core.c
 F:	drivers/rtc/rtc-mpfs.c
 F:	drivers/soc/microchip/
 F:	drivers/spi/spi-microchip-core.c
-- 
2.36.1

Re: [PATCH v4 2/4] riscv: dts: fix the icicle's #pwm-cells

[Conor.Dooley]

On 08/07/2022 15:29, Conor Dooley wrote:
> \#pwm-cells for the Icicle kit's fabric PWM was incorrectly set to 2 &
> blindly overridden by the (out of tree) driver anyway. The core can
> support inverted operation, so update the entry to correctly report its
> capabilities.
> 
> Fixes: 72560c6559b8 ("riscv: dts: microchip: add fpga fabric section to icicle kit")
> Signed-off-by: Conor Dooley <conor.dooley@microchip.com>

Gah, I messed this patch up... I'll resend.

> ---
>   .../dts/microchip/mpfs-icicle-kit-fabric.dtsi |   2 +-
>   .../dts/microchip/mpfs-tysom-m-fabric.dtsi    |  18 ++
>   .../riscv/boot/dts/microchip/mpfs-tysom-m.dts | 185 ++++++++++++++++++
>   3 files changed, 204 insertions(+), 1 deletion(-)
>   create mode 100644 arch/riscv/boot/dts/microchip/mpfs-tysom-m-fabric.dtsi
>   create mode 100644 arch/riscv/boot/dts/microchip/mpfs-tysom-m.dts
> 
> diff --git a/arch/riscv/boot/dts/microchip/mpfs-icicle-kit-fabric.dtsi b/arch/riscv/boot/dts/microchip/mpfs-icicle-kit-fabric.dtsi
> index 0d28858b83f2..e09a13aef268 100644
> --- a/arch/riscv/boot/dts/microchip/mpfs-icicle-kit-fabric.dtsi
> +++ b/arch/riscv/boot/dts/microchip/mpfs-icicle-kit-fabric.dtsi
> @@ -8,7 +8,7 @@ core_pwm0: pwm@41000000 {
>   		compatible = "microchip,corepwm-rtl-v4";
>   		reg = <0x0 0x41000000 0x0 0xF0>;
>   		microchip,sync-update-mask = /bits/ 32 <0>;
> -		#pwm-cells = <2>;
> +		#pwm-cells = <3>;
>   		clocks = <&fabric_clk3>;
>   		status = "disabled";
>   	};
> diff --git a/arch/riscv/boot/dts/microchip/mpfs-tysom-m-fabric.dtsi b/arch/riscv/boot/dts/microchip/mpfs-tysom-m-fabric.dtsi
> new file mode 100644
> index 000000000000..98f642e83ad4
> --- /dev/null
> +++ b/arch/riscv/boot/dts/microchip/mpfs-tysom-m-fabric.dtsi
> @@ -0,0 +1,18 @@
> +// SPDX-License-Identifier: (GPL-2.0 OR MIT)
> +/* Copyright (c) 2022 Microchip Technology Inc */
> +
> +// #include "dt-bindings/mailbox/miv-ihc.h"
> +
> +/ {
> +	fabric_clk3: fabric-clk3 {
> +		compatible = "fixed-clock";
> +		#clock-cells = <0>;
> +		clock-frequency = <62500000>;
> +	};
> +
> +	fabric_clk1: fabric-clk1 {
> +		compatible = "fixed-clock";
> +		#clock-cells = <0>;
> +		clock-frequency = <125000000>;
> +	};
> +};
> diff --git a/arch/riscv/boot/dts/microchip/mpfs-tysom-m.dts b/arch/riscv/boot/dts/microchip/mpfs-tysom-m.dts
> new file mode 100644
> index 000000000000..0b664c591255
> --- /dev/null
> +++ b/arch/riscv/boot/dts/microchip/mpfs-tysom-m.dts
> @@ -0,0 +1,185 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Original all-in-one devicetree:
> + * Copyright (C) 2020-2022 - Aldec
> + * Rewritten to use includes:
> + * Copyright (C) 2022 - Conor Dooley <conor.dooley@microchip.com>
> + */
> +
> +/dts-v1/;
> +
> +#include "mpfs.dtsi"
> +#include "mpfs-tysom-m-fabric.dtsi"
> +
> +/* Clock frequency (in Hz) of the rtcclk */
> +#define MTIMER_FREQ		1000000
> +
> +/ {
> +	model = "Aldec TySOM-M-MPFS250T";
> +	compatible = "aldec,tysom-m-mpfs250t", "microchip,mpfs";
> +
> +	aliases {
> +		ethernet0 = &mac0;
> +		ethernet1 = &mac1;
> +		serial0 = &mmuart0;
> +		serial1 = &mmuart1;
> +		serial2 = &mmuart2;
> +		serial3 = &mmuart3;
> +		serial4 = &mmuart4;
> +		gpio0 = &gpio0;
> +		gpio1 = &gpio2;
> +	};
> +
> +	chosen {
> +		stdout-path = "serial1:115200n8";
> +	};
> +
> +	cpus {
> +		timebase-frequency = <MTIMER_FREQ>;
> +	};
> +
> +	ddrc_cache_lo: memory@80000000 {
> +		device_type = "memory";
> +		reg = <0x0 0x80000000 0x0 0x2e000000>;
> +		status = "okay";
> +	};
> +
> +	ddrc_cache_hi: memory@1000000000 {
> +		device_type = "memory";
> +		reg = <0x10 0x00000000 0x0 0x40000000>;
> +		status = "okay";
> +	};
> +
> +	soc {
> +	};
> +
> +	leds {
> +		compatible = "gpio-leds";
> +		status = "okay";
> +
> +		led0 {
> +			gpios = <&gpio1 23 1>;
> +			default-state = "on";
> +			linux,default-trigger = "heartbeat";
> +		};
> +	};
> +};
> +
> +&i2c0 {
> +	status = "okay";
> +};
> +
> +&i2c1 {
> +	status = "okay";
> +	ina219: ina219@45 {
> +		status = "okay";
> +		compatible = "ti,ina219";
> +		reg = <0x45>;
> +		shunt-resistor = <0x7d0>;
> +	};
> +};
> +
> +&gpio1 {
> +	interrupts = <27 28 29 30 31 32 33 47 35 36 37 38 39 40 41 42 43 44 45 46 34 48 49 50>;
> +	status = "okay";
> +};
> +
> +&mac0 {
> +	status = "okay";
> +	phy-mode = "gmii";
> +	phy-handle = <&phy0>;
> +
> +};
> +
> +&mac1 {
> +	status = "okay";
> +	phy-mode = "gmii";
> +	phy-handle = <&phy1>;
> +	phy1: ethernet-phy@1 {
> +		reg = <1>;
> +		ti,fifo-depth = <0x01>;
> +	};
> +	phy0: ethernet-phy@0 {
> +		reg = <0>;
> +		ti,fifo-depth = <0x01>;
> +	};
> +};
> +
> +&mbox {
> +	status = "okay";
> +};
> +
> +&mmc {
> +	max-frequency = <200000000>;
> +	cap-mmc-highspeed;
> +	cap-sd-highspeed;
> +	no-1-8-v;
> +	disable-wp;
> +	status = "okay";
> +};
> +
> +&mmuart1 {
> +	status = "okay";
> +};
> +
> +&mmuart2 {
> +	status = "okay";
> +};
> +
> +&mmuart3 {
> +	status = "okay";
> +};
> +
> +&mmuart4 {
> +	status = "okay";
> +};
> +
> +&refclk {
> +	clock-frequency = <125000000>;
> +};
> +
> +&rtc {
> +	status = "okay";
> +};
> +
> +&spi0 {
> +	status = "okay";
> +};
> +
> +&spi1 {
> +	status = "okay";
> +	pseFlash@0 {
> +		#address-cells = <1>;
> +		#size-cells = <1>;
> +		compatible = "n25q128a11", "jedec,spi-nor";
> +		status = "okay";
> +		reg = <0x0>;
> +		spi-max-frequency = <10000000>;
> +
> +		partition@test-0 { /* test purposes */
> +			label = "qspi-test-0";
> +			reg = <0x00000000 0x00800000>;
> +		};
> +		partition@test-1 { /* test purposes */
> +			label = "qspi-test-1";
> +			reg = <0x00800000 0x00800000>;
> +		};
> +		partition@test-2 { /* test purposes */
> +			label = "qspi-test-2";
> +			reg = <0x01000000 0x00800000>;
> +		};
> +		partition@test-3 { /* test purposes */
> +			label = "qspi-test-3";
> +			reg = <0x01800000 0x00800000>;
> +		};
> +	};
> +};
> +
> +&syscontroller {
> +	status = "okay";
> +};
> +
> +&usb {
> +	status = "okay";
> +	dr_mode = "host";
> +};