net: ti: icss-iep: Add IEP driver

Add a driver for Industrial Ethernet Peripheral (IEP) block of PRUSS to
support timestamping of ethernet packets and thus support PTP and PPS
for PRU ethernet ports.

Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/ti/Kconfig

@@ -196,4 +196,15 @@ config TI_ICSSG_PRUETH
 	  to support the Ethernet operation. Currently, it supports Ethernet
 	  with 1G and 100M link speed.
 
+config TI_ICSS_IEP
+	tristate "TI PRU ICSS IEP driver"
+	depends on TI_PRUSS
+	default TI_PRUSS
+	help
+	  This driver enables support for the PRU-ICSS Industrial Ethernet
+	  Peripheral within a PRU-ICSS subsystem present on various TI SoCs.
+
+	  To compile this driver as a module, choose M here. The module
+	  will be called icss_iep.
+
 endif # NET_VENDOR_TI

drivers/net/ethernet/ti/Makefile

@@ -38,3 +38,4 @@ icssg-prueth-y := k3-cppi-desc-pool.o \
 		  icssg/icssg_mii_cfg.o \
 		  icssg/icssg_stats.o \
 		  icssg/icssg_ethtool.o
+obj-$(CONFIG_TI_ICSS_IEP) += icssg/icss_iep.o

drivers/net/ethernet/ti/icssg/icss_iep.h

@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Texas Instruments ICSSG Industrial Ethernet Peripheral (IEP) Driver
+ *
+ * Copyright (C) 2023 Texas Instruments Incorporated - https://www.ti.com/
+ *
+ */
+
+#ifndef __NET_TI_ICSS_IEP_H
+#define __NET_TI_ICSS_IEP_H
+
+#include <linux/mutex.h>
+#include <linux/ptp_clock_kernel.h>
+#include <linux/regmap.h>
+
+struct icss_iep;
+
+/* Firmware specific clock operations */
+struct icss_iep_clockops {
+	void (*settime)(void *clockops_data, u64 ns);
+	void (*adjtime)(void *clockops_data, s64 delta);
+	u64 (*gettime)(void *clockops_data, struct ptp_system_timestamp *sts);
+	int (*perout_enable)(void *clockops_data,
+			     struct ptp_perout_request *req, int on,
+			     u64 *cmp);
+	int (*extts_enable)(void *clockops_data, u32 index, int on);
+};
+
+struct icss_iep *icss_iep_get(struct device_node *np);
+struct icss_iep *icss_iep_get_idx(struct device_node *np, int idx);
+void icss_iep_put(struct icss_iep *iep);
+int icss_iep_init(struct icss_iep *iep, const struct icss_iep_clockops *clkops,
+		  void *clockops_data, u32 cycle_time_ns);
+int icss_iep_exit(struct icss_iep *iep);
+int icss_iep_get_count_low(struct icss_iep *iep);
+int icss_iep_get_count_hi(struct icss_iep *iep);
+int icss_iep_get_ptp_clock_idx(struct icss_iep *iep);
+
+#endif /* __NET_TI_ICSS_IEP_H */