[RFC,net-next,v2,2/8] net: dsa: microchip: adding the posix clock support

Message ID 20221121154150.9573-3-arun.ramadoss@microchip.com
State New
Headers
Series net: dsa: microchip: add PTP support for KSZ9x and LAN937x |

Commit Message

Arun Ramadoss Nov. 21, 2022, 3:41 p.m. UTC
  This patch implement routines (adjfine, adjtime, gettime and settime)
for manipulating the chip's PTP clock. It registers the ptp caps
to posix clock register.

Signed-off-by: Christian Eggers <ceggers@arri.de>
Signed-off-by: Arun Ramadoss <arun.ramadoss@microchip.com>
---
 drivers/net/dsa/microchip/Kconfig       |  12 ++
 drivers/net/dsa/microchip/Makefile      |   5 +
 drivers/net/dsa/microchip/ksz_common.c  |  14 +-
 drivers/net/dsa/microchip/ksz_common.h  |  17 ++
 drivers/net/dsa/microchip/ksz_ptp.c     | 270 ++++++++++++++++++++++++
 drivers/net/dsa/microchip/ksz_ptp.h     |  43 ++++
 drivers/net/dsa/microchip/ksz_ptp_reg.h |  52 +++++
 7 files changed, 412 insertions(+), 1 deletion(-)
 create mode 100644 drivers/net/dsa/microchip/ksz_ptp.c
 create mode 100644 drivers/net/dsa/microchip/ksz_ptp.h
 create mode 100644 drivers/net/dsa/microchip/ksz_ptp_reg.h
  

Comments

Vladimir Oltean Nov. 21, 2022, 9:33 p.m. UTC | #1
On Mon, Nov 21, 2022 at 09:11:44PM +0530, Arun Ramadoss wrote:
> +int ksz_ptp_clock_register(struct dsa_switch *ds)
> +{
> +	/* Register the PTP Clock */
> +	ptp_data->clock = ptp_clock_register(&ptp_data->caps, dev->dev);
> +	if (IS_ERR_OR_NULL(ptp_data->clock))
> +		return PTR_ERR(ptp_data->clock);
> +}
> +
> +void ksz_ptp_clock_unregister(struct dsa_switch *ds)
> +{
> +	struct ksz_device *dev = ds->priv;
> +	struct ksz_ptp_data *ptp_data = &dev->ptp_data;
> +
> +	if (IS_ERR_OR_NULL(ptp_data->clock))
> +		return;
> +
> +	ptp_clock_unregister(ptp_data->clock);
> +}

API usage seems to be incorrect here (probably copied from sja1105 which
is written by me and also incorrect, yay).

The intention with IS_ERR_OR_NULL() is for the caller to return 0
(success) when ptp_clock_register() returns NULL (when PTP support
is compiled out), and this will not make the driver fail to probe.

There isn't a reason to use IS_ERR_OR_NULL() in the normal unregister
code path, because the code won't get there in the IS_ERR() case.
So a simple "if (ptp_data->clock) ptp_clock_unregister(ptp_data->clock)"
would do.
  
Vladimir Oltean Nov. 21, 2022, 10:01 p.m. UTC | #2
On Mon, Nov 21, 2022 at 09:11:44PM +0530, Arun Ramadoss wrote:
> @@ -17,10 +18,21 @@ config NET_DSA_MICROCHIP_KSZ9477_I2C
>  config NET_DSA_MICROCHIP_KSZ_SPI
>  	tristate "KSZ series SPI connected switch driver"
>  	depends on NET_DSA_MICROCHIP_KSZ_COMMON && SPI
> +	depends on PTP_1588_CLOCK_OPTIONAL
>  	select REGMAP_SPI
>  	help
>  	  Select to enable support for registering switches configured through SPI.
>  
> +config NET_DSA_MICROCHIP_KSZ_PTP
> +	bool "Support for the PTP clock on the KSZ9563/LAN937x Ethernet Switch"
> +	depends on NET_DSA_MICROCHIP_KSZ_COMMON && PTP_1588_CLOCK
> +	help
> +	  This enables support for timestamping & PTP clock manipulation

Please use "and" instead of "&".

> +	  in the KSZ9563/LAN937x Ethernet switch
> +
> +	  Select to enable support for PTP feature for KSZ9563/lan937x series

Please capitalize both KSZ9563 and LAN937X. This help text is the
business card of the feature, you need it to look nice and shiny.

Also, "for PTP feature for ..."? How about "enable PTP hardware
timestamping and clock manipulation support for ..."?

> +	  of switch.

switches

> +
>  config NET_DSA_MICROCHIP_KSZ8863_SMI
>  	tristate "KSZ series SMI connected switch driver"
>  	depends on NET_DSA_MICROCHIP_KSZ_COMMON
> diff --git a/drivers/net/dsa/microchip/ksz_ptp.c b/drivers/net/dsa/microchip/ksz_ptp.c
> new file mode 100644
> index 000000000000..cad0c6087419
> --- /dev/null
> +++ b/drivers/net/dsa/microchip/ksz_ptp.c
> @@ -0,0 +1,270 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Microchip LAN937X PTP Implementation
> + * Copyright (C) 2021-2022 Microchip Technology Inc.
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/ptp_classify.h>
> +#include <linux/ptp_clock_kernel.h>
> +
> +#include "ksz_common.h"
> +#include "ksz_ptp.h"
> +#include "ksz_ptp_reg.h"
> +
> +#define ptp_caps_to_data(d) \
> +		container_of((d), struct ksz_ptp_data, caps)
> +#define ptp_data_to_ksz_dev(d) \
> +		container_of((d), struct ksz_device, ptp_data)
> +
> +#define MAX_DRIFT_CORR 6250000

KSZ_MAX_DRIFT_CORR maybe? Also maybe a small comment about the
assumptions that were made when it was calculated?

> +
> +#define KSZ_PTP_INC_NS 40  /* HW clock is incremented every 40 ns (by 40) */
> +#define KSZ_PTP_SUBNS_BITS 32  /* Number of bits in sub-nanoseconds counter */
> +
> +/* The function is return back the capability of timestamping feature when
> + * requested through ethtool -T <interface> utility
> + */
> +int ksz_get_ts_info(struct dsa_switch *ds, int port, struct ethtool_ts_info *ts)
> +{
> +	struct ksz_device *dev	= ds->priv;
> +	struct ksz_ptp_data *ptp_data = &dev->ptp_data;
> +
> +	ts->so_timestamping = SOF_TIMESTAMPING_TX_HARDWARE |
> +			      SOF_TIMESTAMPING_RX_HARDWARE |
> +			      SOF_TIMESTAMPING_RAW_HARDWARE;
> +
> +	ts->tx_types = (1 << HWTSTAMP_TX_OFF);
> +
> +	ts->rx_filters = (1 << HWTSTAMP_FILTER_NONE);
> +
> +	ts->phc_index = ptp_clock_index(ptp_data->clock);

Ah, but I don't think the optionality of ptp_data->clock is dealt with
very well here. ptp_data->clock can be NULL, and ethtool -T can still be
run on the interface. That will dereference a NULL pointer in ptp_clock_index().

int ptp_clock_index(struct ptp_clock *ptp)
{
	return ptp->index;
}
EXPORT_SYMBOL(ptp_clock_index);

> +
> +	return 0;
> +}
> +
> +int ksz_ptp_clock_register(struct dsa_switch *ds)
> +{
> +	struct ksz_device *dev = ds->priv;
> +	struct ksz_ptp_data *ptp_data = &dev->ptp_data;
> +	int ret;
> +
> +	mutex_init(&ptp_data->lock);
> +
> +	ptp_data->caps = ksz_ptp_caps;
> +
> +	/* Start hardware counter */
> +	ret = ksz_ptp_start_clock(dev);
> +	if (ret)
> +		return ret;
> +
> +	/* Register the PTP Clock */
> +	ptp_data->clock = ptp_clock_register(&ptp_data->caps, dev->dev);
> +	if (IS_ERR_OR_NULL(ptp_data->clock))
> +		return PTR_ERR(ptp_data->clock);
> +
> +	ret = ksz_rmw16(dev, REG_PTP_MSG_CONF1, PTP_802_1AS, PTP_802_1AS);

A small comment as to what this does? I see in other places you're
generous with comments, like "Register the PTP clock" above the
ptp_clock_register() call.

> +	if (ret)
> +		goto error_unregister_clock;
> +
> +	return 0;
> +
> +error_unregister_clock:
> +	ptp_clock_unregister(ptp_data->clock);
> +	return ret;
> +}
> +
> +MODULE_AUTHOR("Christian Eggers <ceggers@arri.de>");
> +MODULE_AUTHOR("Arun Ramadoss <arun.ramadoss@microchip.com>");
> +MODULE_DESCRIPTION("PTP support for KSZ switch");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/net/dsa/microchip/ksz_ptp.h b/drivers/net/dsa/microchip/ksz_ptp.h
> new file mode 100644
> index 000000000000..ac53b0df2733
> --- /dev/null
> +++ b/drivers/net/dsa/microchip/ksz_ptp.h
> @@ -0,0 +1,43 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/* Microchip LAN937X PTP Implementation
> + * Copyright (C) 2020-2021 Microchip Technology Inc.
> + */
> +
> +#ifndef _NET_DSA_DRIVERS_KSZ_PTP_H
> +#define _NET_DSA_DRIVERS_KSZ_PTP_H
> +
> +#if IS_ENABLED(CONFIG_NET_DSA_MICROCHIP_KSZ_PTP)
> +
> +#endif	/* End of CONFIG_NET_DSA_MICROCHIOP_KSZ_PTP */

MICROCHIP not MICROCHIOP

> +
> +#endif
  

Patch

diff --git a/drivers/net/dsa/microchip/Kconfig b/drivers/net/dsa/microchip/Kconfig
index 06b1efdb5e7d..a1a3a04d0ea2 100644
--- a/drivers/net/dsa/microchip/Kconfig
+++ b/drivers/net/dsa/microchip/Kconfig
@@ -10,6 +10,7 @@  menuconfig NET_DSA_MICROCHIP_KSZ_COMMON
 config NET_DSA_MICROCHIP_KSZ9477_I2C
 	tristate "KSZ series I2C connected switch driver"
 	depends on NET_DSA_MICROCHIP_KSZ_COMMON && I2C
+	depends on PTP_1588_CLOCK_OPTIONAL
 	select REGMAP_I2C
 	help
 	  Select to enable support for registering switches configured through I2C.
@@ -17,10 +18,21 @@  config NET_DSA_MICROCHIP_KSZ9477_I2C
 config NET_DSA_MICROCHIP_KSZ_SPI
 	tristate "KSZ series SPI connected switch driver"
 	depends on NET_DSA_MICROCHIP_KSZ_COMMON && SPI
+	depends on PTP_1588_CLOCK_OPTIONAL
 	select REGMAP_SPI
 	help
 	  Select to enable support for registering switches configured through SPI.
 
+config NET_DSA_MICROCHIP_KSZ_PTP
+	bool "Support for the PTP clock on the KSZ9563/LAN937x Ethernet Switch"
+	depends on NET_DSA_MICROCHIP_KSZ_COMMON && PTP_1588_CLOCK
+	help
+	  This enables support for timestamping & PTP clock manipulation
+	  in the KSZ9563/LAN937x Ethernet switch
+
+	  Select to enable support for PTP feature for KSZ9563/lan937x series
+	  of switch.
+
 config NET_DSA_MICROCHIP_KSZ8863_SMI
 	tristate "KSZ series SMI connected switch driver"
 	depends on NET_DSA_MICROCHIP_KSZ_COMMON
diff --git a/drivers/net/dsa/microchip/Makefile b/drivers/net/dsa/microchip/Makefile
index 28873559efc2..48360cc9fc68 100644
--- a/drivers/net/dsa/microchip/Makefile
+++ b/drivers/net/dsa/microchip/Makefile
@@ -4,6 +4,11 @@  ksz_switch-objs := ksz_common.o
 ksz_switch-objs += ksz9477.o
 ksz_switch-objs += ksz8795.o
 ksz_switch-objs += lan937x_main.o
+
+ifdef CONFIG_NET_DSA_MICROCHIP_KSZ_PTP
+ksz_switch-objs += ksz_ptp.o
+endif
+
 obj-$(CONFIG_NET_DSA_MICROCHIP_KSZ9477_I2C)	+= ksz9477_i2c.o
 obj-$(CONFIG_NET_DSA_MICROCHIP_KSZ_SPI)		+= ksz_spi.o
 obj-$(CONFIG_NET_DSA_MICROCHIP_KSZ8863_SMI)	+= ksz8863_smi.o
diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
index 8c8db315317d..eb77eca0dcb2 100644
--- a/drivers/net/dsa/microchip/ksz_common.c
+++ b/drivers/net/dsa/microchip/ksz_common.c
@@ -27,6 +27,7 @@ 
 #include "ksz8.h"
 #include "ksz9477.h"
 #include "lan937x.h"
+#include "ksz_ptp.h"
 
 #define MIB_COUNTER_NUM 0x20
 
@@ -2016,10 +2017,16 @@  static int ksz_setup(struct dsa_switch *ds)
 		}
 	}
 
+	ret = ksz_ptp_clock_register(ds);
+	if (ret) {
+		dev_err(dev->dev, "Failed to register PTP clock: %d\n", ret);
+		goto out_pirq;
+	}
+
 	ret = ksz_mdio_register(dev);
 	if (ret < 0) {
 		dev_err(dev->dev, "failed to register the mdio");
-		goto out_pirq;
+		goto out_ptp_clock_unregister;
 	}
 
 	/* start switch */
@@ -2028,6 +2035,8 @@  static int ksz_setup(struct dsa_switch *ds)
 
 	return 0;
 
+out_ptp_clock_unregister:
+	ksz_ptp_clock_unregister(ds);
 out_pirq:
 	if (dev->irq > 0)
 		dsa_switch_for_each_user_port(dp, dev->ds)
@@ -2044,6 +2053,8 @@  static void ksz_teardown(struct dsa_switch *ds)
 	struct ksz_device *dev = ds->priv;
 	struct dsa_port *dp;
 
+	ksz_ptp_clock_unregister(ds);
+
 	if (dev->irq > 0) {
 		dsa_switch_for_each_user_port(dp, dev->ds)
 			ksz_irq_free(&dev->ports[dp->index].pirq);
@@ -2861,6 +2872,7 @@  static const struct dsa_switch_ops ksz_switch_ops = {
 	.get_pause_stats	= ksz_get_pause_stats,
 	.port_change_mtu	= ksz_change_mtu,
 	.port_max_mtu		= ksz_max_mtu,
+	.get_ts_info            = ksz_get_ts_info,
 };
 
 struct ksz_device *ksz_switch_alloc(struct device *base, void *priv)
diff --git a/drivers/net/dsa/microchip/ksz_common.h b/drivers/net/dsa/microchip/ksz_common.h
index c6726cbd5465..767f17d2c75d 100644
--- a/drivers/net/dsa/microchip/ksz_common.h
+++ b/drivers/net/dsa/microchip/ksz_common.h
@@ -14,6 +14,9 @@ 
 #include <linux/regmap.h>
 #include <net/dsa.h>
 #include <linux/irq.h>
+#include <linux/ptp_clock_kernel.h>
+
+#include "ksz_ptp.h"
 
 #define KSZ_MAX_NUM_PORTS 8
 
@@ -141,6 +144,7 @@  struct ksz_device {
 	u16 port_mask;
 	struct mutex lock_irq;		/* IRQ Access */
 	struct ksz_irq girq;
+	struct ksz_ptp_data ptp_data;
 };
 
 /* List of supported models */
@@ -444,6 +448,19 @@  static inline int ksz_write32(struct ksz_device *dev, u32 reg, u32 value)
 	return ret;
 }
 
+static inline int ksz_rmw16(struct ksz_device *dev, u32 reg, u16 mask,
+			    u16 value)
+{
+	int ret;
+
+	ret = regmap_update_bits(dev->regmap[1], reg, mask, value);
+	if (ret)
+		dev_err(dev->dev, "can't rmw 16bit reg: 0x%x %pe\n", reg,
+			ERR_PTR(ret));
+
+	return ret;
+}
+
 static inline int ksz_write64(struct ksz_device *dev, u32 reg, u64 value)
 {
 	u32 val[2];
diff --git a/drivers/net/dsa/microchip/ksz_ptp.c b/drivers/net/dsa/microchip/ksz_ptp.c
new file mode 100644
index 000000000000..cad0c6087419
--- /dev/null
+++ b/drivers/net/dsa/microchip/ksz_ptp.c
@@ -0,0 +1,270 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/* Microchip LAN937X PTP Implementation
+ * Copyright (C) 2021-2022 Microchip Technology Inc.
+ */
+
+#include <linux/kernel.h>
+#include <linux/ptp_classify.h>
+#include <linux/ptp_clock_kernel.h>
+
+#include "ksz_common.h"
+#include "ksz_ptp.h"
+#include "ksz_ptp_reg.h"
+
+#define ptp_caps_to_data(d) \
+		container_of((d), struct ksz_ptp_data, caps)
+#define ptp_data_to_ksz_dev(d) \
+		container_of((d), struct ksz_device, ptp_data)
+
+#define MAX_DRIFT_CORR 6250000
+
+#define KSZ_PTP_INC_NS 40  /* HW clock is incremented every 40 ns (by 40) */
+#define KSZ_PTP_SUBNS_BITS 32  /* Number of bits in sub-nanoseconds counter */
+
+/* The function is return back the capability of timestamping feature when
+ * requested through ethtool -T <interface> utility
+ */
+int ksz_get_ts_info(struct dsa_switch *ds, int port, struct ethtool_ts_info *ts)
+{
+	struct ksz_device *dev	= ds->priv;
+	struct ksz_ptp_data *ptp_data = &dev->ptp_data;
+
+	ts->so_timestamping = SOF_TIMESTAMPING_TX_HARDWARE |
+			      SOF_TIMESTAMPING_RX_HARDWARE |
+			      SOF_TIMESTAMPING_RAW_HARDWARE;
+
+	ts->tx_types = (1 << HWTSTAMP_TX_OFF);
+
+	ts->rx_filters = (1 << HWTSTAMP_FILTER_NONE);
+
+	ts->phc_index = ptp_clock_index(ptp_data->clock);
+
+	return 0;
+}
+
+/* These are function related to the ptp clock info */
+static int _ksz_ptp_gettime(struct ksz_device *dev, struct timespec64 *ts)
+{
+	u32 nanoseconds;
+	u32 seconds;
+	u8 phase;
+	int ret;
+
+	/* Copy current PTP clock into shadow registers */
+	ret = ksz_rmw16(dev, REG_PTP_CLK_CTRL, PTP_READ_TIME, PTP_READ_TIME);
+	if (ret)
+		return ret;
+
+	/* Read from shadow registers */
+	ret = ksz_read8(dev, REG_PTP_RTC_SUB_NANOSEC__2, &phase);
+	if (ret)
+		return ret;
+
+	ret = ksz_read32(dev, REG_PTP_RTC_NANOSEC, &nanoseconds);
+	if (ret)
+		return ret;
+
+	ret = ksz_read32(dev, REG_PTP_RTC_SEC, &seconds);
+	if (ret)
+		return ret;
+
+	ts->tv_sec = seconds;
+	ts->tv_nsec = nanoseconds + phase * 8;
+
+	return 0;
+}
+
+static int ksz_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
+{
+	struct ksz_ptp_data *ptp_data = ptp_caps_to_data(ptp);
+	struct ksz_device *dev = ptp_data_to_ksz_dev(ptp_data);
+	int ret;
+
+	mutex_lock(&ptp_data->lock);
+	ret = _ksz_ptp_gettime(dev, ts);
+	mutex_unlock(&ptp_data->lock);
+
+	return ret;
+}
+
+static int ksz_ptp_settime(struct ptp_clock_info *ptp,
+			   const struct timespec64 *ts)
+{
+	struct ksz_ptp_data *ptp_data = ptp_caps_to_data(ptp);
+	struct ksz_device *dev = ptp_data_to_ksz_dev(ptp_data);
+	int ret;
+
+	mutex_lock(&ptp_data->lock);
+
+	/* Write to shadow registers */
+
+	/* Write 0 to clock phase */
+	ret = ksz_write16(dev, REG_PTP_RTC_SUB_NANOSEC__2, PTP_RTC_0NS);
+	if (ret)
+		goto error_return;
+
+	/* nanoseconds */
+	ret = ksz_write32(dev, REG_PTP_RTC_NANOSEC, ts->tv_nsec);
+	if (ret)
+		goto error_return;
+
+	/* seconds */
+	ret = ksz_write32(dev, REG_PTP_RTC_SEC, ts->tv_sec);
+	if (ret)
+		goto error_return;
+
+	/* Load PTP clock from shadow registers */
+	ret = ksz_rmw16(dev, REG_PTP_CLK_CTRL, PTP_LOAD_TIME, PTP_LOAD_TIME);
+
+error_return:
+	mutex_unlock(&ptp_data->lock);
+
+	return ret;
+}
+
+static int ksz_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
+{
+	struct ksz_ptp_data *ptp_data = ptp_caps_to_data(ptp);
+	struct ksz_device *dev = ptp_data_to_ksz_dev(ptp_data);
+	int ret;
+
+	mutex_lock(&ptp_data->lock);
+
+	if (scaled_ppm) {
+		s64 ppb, adj;
+		u32 data32;
+
+		/* see scaled_ppm_to_ppb() in ptp_clock.c for details */
+		ppb = 1 + scaled_ppm;
+		ppb *= 125;
+		ppb *= KSZ_PTP_INC_NS;
+		ppb <<= KSZ_PTP_SUBNS_BITS - 13;
+		adj = div_s64(ppb, NSEC_PER_SEC);
+
+		data32 = abs(adj);
+		data32 &= PTP_SUBNANOSEC_M;
+		if (adj >= 0)
+			data32 |= PTP_RATE_DIR;
+
+		ret = ksz_write32(dev, REG_PTP_SUBNANOSEC_RATE, data32);
+		if (ret)
+			goto error_return;
+
+		ret = ksz_rmw16(dev, REG_PTP_CLK_CTRL, PTP_CLK_ADJ_ENABLE,
+				PTP_CLK_ADJ_ENABLE);
+		if (ret)
+			goto error_return;
+	} else {
+		ret = ksz_rmw16(dev, REG_PTP_CLK_CTRL, PTP_CLK_ADJ_ENABLE, 0);
+		if (ret)
+			goto error_return;
+	}
+
+error_return:
+	mutex_unlock(&ptp_data->lock);
+	return ret;
+}
+
+static int ksz_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
+{
+	struct ksz_ptp_data *ptp_data = ptp_caps_to_data(ptp);
+	struct ksz_device *dev = ptp_data_to_ksz_dev(ptp_data);
+	s32 sec, nsec;
+	u16 data16;
+	int ret;
+
+	mutex_lock(&ptp_data->lock);
+
+	/* do not use ns_to_timespec64(),
+	 * both sec and nsec are subtracted by hw
+	 */
+	sec = div_s64_rem(delta, NSEC_PER_SEC, &nsec);
+
+	ret = ksz_write32(dev, REG_PTP_RTC_NANOSEC, abs(nsec));
+	if (ret)
+		goto error_return;
+
+	ret = ksz_write32(dev, REG_PTP_RTC_SEC, abs(sec));
+	if (ret)
+		goto error_return;
+
+	ret = ksz_read16(dev, REG_PTP_CLK_CTRL, &data16);
+	if (ret)
+		goto error_return;
+
+	data16 |= PTP_STEP_ADJ;
+
+	/*PTP_STEP_DIR -- 0: subtract, 1: add */
+	if (delta < 0)
+		data16 &= ~PTP_STEP_DIR;
+	else
+		data16 |= PTP_STEP_DIR;
+
+	ret = ksz_write16(dev, REG_PTP_CLK_CTRL, data16);
+
+error_return:
+	mutex_unlock(&ptp_data->lock);
+	return ret;
+}
+
+static int ksz_ptp_start_clock(struct ksz_device *dev)
+{
+	return ksz_rmw16(dev, REG_PTP_CLK_CTRL, PTP_CLK_ENABLE, PTP_CLK_ENABLE);
+}
+
+static const struct ptp_clock_info ksz_ptp_caps = {
+	.owner		= THIS_MODULE,
+	.name		= "Microchip Clock",
+	.max_adj	= MAX_DRIFT_CORR,
+	.gettime64	= ksz_ptp_gettime,
+	.settime64	= ksz_ptp_settime,
+	.adjfine	= ksz_ptp_adjfine,
+	.adjtime	= ksz_ptp_adjtime,
+};
+
+int ksz_ptp_clock_register(struct dsa_switch *ds)
+{
+	struct ksz_device *dev = ds->priv;
+	struct ksz_ptp_data *ptp_data = &dev->ptp_data;
+	int ret;
+
+	mutex_init(&ptp_data->lock);
+
+	ptp_data->caps = ksz_ptp_caps;
+
+	/* Start hardware counter */
+	ret = ksz_ptp_start_clock(dev);
+	if (ret)
+		return ret;
+
+	/* Register the PTP Clock */
+	ptp_data->clock = ptp_clock_register(&ptp_data->caps, dev->dev);
+	if (IS_ERR_OR_NULL(ptp_data->clock))
+		return PTR_ERR(ptp_data->clock);
+
+	ret = ksz_rmw16(dev, REG_PTP_MSG_CONF1, PTP_802_1AS, PTP_802_1AS);
+	if (ret)
+		goto error_unregister_clock;
+
+	return 0;
+
+error_unregister_clock:
+	ptp_clock_unregister(ptp_data->clock);
+	return ret;
+}
+
+void ksz_ptp_clock_unregister(struct dsa_switch *ds)
+{
+	struct ksz_device *dev = ds->priv;
+	struct ksz_ptp_data *ptp_data = &dev->ptp_data;
+
+	if (IS_ERR_OR_NULL(ptp_data->clock))
+		return;
+
+	ptp_clock_unregister(ptp_data->clock);
+}
+
+MODULE_AUTHOR("Christian Eggers <ceggers@arri.de>");
+MODULE_AUTHOR("Arun Ramadoss <arun.ramadoss@microchip.com>");
+MODULE_DESCRIPTION("PTP support for KSZ switch");
+MODULE_LICENSE("GPL");
diff --git a/drivers/net/dsa/microchip/ksz_ptp.h b/drivers/net/dsa/microchip/ksz_ptp.h
new file mode 100644
index 000000000000..ac53b0df2733
--- /dev/null
+++ b/drivers/net/dsa/microchip/ksz_ptp.h
@@ -0,0 +1,43 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Microchip LAN937X PTP Implementation
+ * Copyright (C) 2020-2021 Microchip Technology Inc.
+ */
+
+#ifndef _NET_DSA_DRIVERS_KSZ_PTP_H
+#define _NET_DSA_DRIVERS_KSZ_PTP_H
+
+#if IS_ENABLED(CONFIG_NET_DSA_MICROCHIP_KSZ_PTP)
+
+struct ksz_ptp_data {
+	struct ptp_clock_info caps;
+	struct ptp_clock *clock;
+	/* Serializes all operations on the PTP hardware clock */
+	struct mutex lock;
+};
+
+int ksz_ptp_clock_register(struct dsa_switch *ds);
+
+void ksz_ptp_clock_unregister(struct dsa_switch *ds);
+
+int ksz_get_ts_info(struct dsa_switch *ds, int port,
+		    struct ethtool_ts_info *ts);
+
+#else
+
+struct ksz_ptp_data {
+	/* Serializes all operations on the PTP hardware clock */
+	struct mutex lock;
+};
+
+static inline int ksz_ptp_clock_register(struct dsa_switch *ds)
+{
+	return 0;
+}
+
+static inline void ksz_ptp_clock_unregister(struct dsa_switch *ds) { }
+
+#define ksz_get_ts_info NULL
+
+#endif	/* End of CONFIG_NET_DSA_MICROCHIOP_KSZ_PTP */
+
+#endif
diff --git a/drivers/net/dsa/microchip/ksz_ptp_reg.h b/drivers/net/dsa/microchip/ksz_ptp_reg.h
new file mode 100644
index 000000000000..2bf8395475b9
--- /dev/null
+++ b/drivers/net/dsa/microchip/ksz_ptp_reg.h
@@ -0,0 +1,52 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Microchip KSZ PTP register definitions
+ * Copyright (C) 2019-2021 Microchip Technology Inc.
+ */
+
+/* 5 - PTP Clock */
+#define REG_PTP_CLK_CTRL		0x0500
+
+#define PTP_STEP_ADJ			BIT(6)
+#define PTP_STEP_DIR			BIT(5)
+#define PTP_READ_TIME			BIT(4)
+#define PTP_LOAD_TIME			BIT(3)
+#define PTP_CLK_ADJ_ENABLE		BIT(2)
+#define PTP_CLK_ENABLE			BIT(1)
+#define PTP_CLK_RESET			BIT(0)
+
+#define REG_PTP_RTC_SUB_NANOSEC__2	0x0502
+
+#define PTP_RTC_SUB_NANOSEC_M		0x0007
+#define PTP_RTC_0NS			0x00
+
+#define REG_PTP_RTC_NANOSEC		0x0504
+#define REG_PTP_RTC_NANOSEC_H		0x0504
+#define REG_PTP_RTC_NANOSEC_L		0x0506
+
+#define REG_PTP_RTC_SEC			0x0508
+#define REG_PTP_RTC_SEC_H		0x0508
+#define REG_PTP_RTC_SEC_L		0x050A
+
+#define REG_PTP_SUBNANOSEC_RATE		0x050C
+#define REG_PTP_SUBNANOSEC_RATE_H	0x050C
+#define PTP_SUBNANOSEC_M		0x3FFFFFFF
+
+#define PTP_RATE_DIR			BIT(31)
+#define PTP_TMP_RATE_ENABLE		BIT(30)
+
+#define REG_PTP_SUBNANOSEC_RATE_L	0x050E
+
+#define REG_PTP_RATE_DURATION		0x0510
+#define REG_PTP_RATE_DURATION_H		0x0510
+#define REG_PTP_RATE_DURATION_L		0x0512
+
+#define REG_PTP_MSG_CONF1		0x0514
+
+#define PTP_802_1AS			BIT(7)
+#define PTP_ENABLE			BIT(6)
+#define PTP_ETH_ENABLE			BIT(5)
+#define PTP_IPV4_UDP_ENABLE		BIT(4)
+#define PTP_IPV6_UDP_ENABLE		BIT(3)
+#define PTP_TC_P2P			BIT(2)
+#define PTP_MASTER			BIT(1)
+#define PTP_1STEP			BIT(0)