Merge branch 'hirschmann-hellcreek-dsa-driver'

Kurt Kanzenbach says: ==================== Hirschmann Hellcreek DSA driver this series adds a DSA driver for the Hirschmann Hellcreek TSN switch IP. Characteristics of that IP: * Full duplex Ethernet interface at 100/1000 Mbps on three ports * IEEE 802.1Q-compliant Ethernet Switch * IEEE 802.1Qbv Time-Aware scheduling support * IEEE 1588 and IEEE 802.1AS support That IP is used e.g. in https://www.arrow.com/en/campaigns/arrow-kairos Due to the hardware setup the switch driver is implemented using DSA. A special tagging protocol is leveraged. Furthermore, this driver supports PTP and hardware timestamping. This work is part of the AccessTSN project: https://www.accesstsn.com/ The previous versions can be found here: * https://lkml.kernel.org/netdev/20200618064029.32168-1-kurt@linutronix.de/ * https://lkml.kernel.org/netdev/20200710113611.3398-1-kurt@linutronix.de/ * https://lkml.kernel.org/netdev/20200723081714.16005-1-kurt@linutronix.de/ * https://lkml.kernel.org/netdev/20200820081118.10105-1-kurt@linutronix.de/ * https://lkml.kernel.org/netdev/20200901125014.17801-1-kurt@linutronix.de/ * https://lkml.kernel.org/netdev/20200904062739.3540-1-kurt@linutronix.de/ * https://lkml.kernel.org/netdev/20201004112911.25085-1-kurt@linutronix.de/ * https://lkml.kernel.org/netdev/20201028074221.29326-1-kurt@linutronix.de/ Changes since v7: * Simplify tagging code (rebase to net-next) * Pass info instead of ptr (Florian Fainelli) * Fix yamllint warnings (Rob Herring) Changes since v6: * Add .tail_tag = true (Vladimir Oltean) * Fix vlan_filtering=0 bridges (Vladimir Oltean) * Enforce restrictions (Vladimir Oltean) * Sort stuff alphabetically (Vladimir Oltean) * Rename hellcreek.yaml to hirschmann,hellcreek.yaml * Typo fixes Changes since v5: * Implement configure_vlan_while_not_filtering behavior (Vladimir Oltean) * Minor cleanups Changes since v4: * Fix W=1 compiler warnings (kernel test robot) * Add tags Changes since v3: * Drop TAPRIO support (David Miller) => Switch to mutexes due to the lack of hrtimers * Use more specific compatible strings and add platform data (Andrew Lunn) * Fix Kconfig ordering (Andrew Lunn) Changes since v2: * Make it compile by getting all requirements merged first (Jakub Kicinski, David Miller) * Use "tsn" for TSN register set (Rob Herring) * Fix DT binding issues (Rob Herring) Changes since v1: * Code simplifications (Florian Fainelli, Vladimir Oltean) * Fix issues with hellcreek.yaml bindings (Florian Fainelli) * Clear reserved field in ptp v2 event messages (Richard Cochran) * Make use of generic ptp parsing function (Richard Cochran, Vladimir Oltean) * Fix Kconfig (Florian Fainelli) * Add tags (Florian Fainelli, Rob Herring, Richard Cochran) Changes since RFC ordered by reviewers: * Andrew Lunn * Use dev_dbg for debug messages * Get rid of __ function names where possible * Use reverse xmas tree variable ordering * Remove redundant/useless checks * Improve comments e.g. for PTP * Fix Kconfig ordering * Make LED handling more generic and provide info via DT * Setup advertisement of PHYs according to hardware * Drop debugfs patch * Jakub Kicinski * Fix compiler warnings * Florian Fainelli * Switch to YAML DT bindings * Richard Cochran * Fix typo * Add missing NULL checks ==================== Link: https://lore.kernel.org/r/20201103071101.3222-1-kurt@linutronix.de Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-11-11 12:28:41 +08:00 · 2020-11-05 14:07:51 -08:00 · 2020-11-05 14:07:51 -08:00 · 67438feb2b
commit 67438feb2b
parent 94f44f2883 d5d29d527a
18 changed files with 2952 additions and 0 deletions
--- a/Documentation/devicetree/bindings/net/dsa/hirschmann,hellcreek.yaml
+++ b/Documentation/devicetree/bindings/net/dsa/hirschmann,hellcreek.yaml
@ -0,0 +1,127 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/net/dsa/hirschmann,hellcreek.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Hirschmann Hellcreek TSN Switch Device Tree Bindings
+
+allOf:
+  - $ref: dsa.yaml#
+
+maintainers:
+  - Andrew Lunn <andrew@lunn.ch>
+  - Florian Fainelli <f.fainelli@gmail.com>
+  - Vivien Didelot <vivien.didelot@gmail.com>
+  - Kurt Kanzenbach <kurt@linutronix.de>
+
+description:
+  The Hellcreek TSN Switch IP is a 802.1Q Ethernet compliant switch. It supports
+  the Precision Time Protocol, Hardware Timestamping as well the Time Aware
+  Shaper.
+
+properties:
+  compatible:
+    items:
+      - const: hirschmann,hellcreek-de1soc-r1
+
+  reg:
+    description:
+      The physical base address and size of TSN and PTP memory base
+    minItems: 2
+    maxItems: 2
+
+  reg-names:
+    items:
+      - const: tsn
+      - const: ptp
+
+  leds:
+    type: object
+    properties:
+      '#address-cells':
+        const: 1
+      '#size-cells':
+        const: 0
+
+    patternProperties:
+      "^led@[01]$":
+        type: object
+        description: Hellcreek leds
+        $ref: ../../leds/common.yaml#
+
+        properties:
+          reg:
+            items:
+              - enum: [0, 1]
+            description: Led number
+
+          label: true
+
+          default-state: true
+
+        required:
+          - reg
+
+        additionalProperties: false
+
+    additionalProperties: false
+
+required:
+  - compatible
+  - reg
+  - reg-names
+  - ethernet-ports
+  - leds
+
+unevaluatedProperties: false
+
+examples:
+  - |
+        switch0: switch@ff240000 {
+            compatible = "hirschmann,hellcreek-de1soc-r1";
+            reg = <0xff240000 0x1000>,
+                  <0xff250000 0x1000>;
+            reg-names = "tsn", "ptp";
+            dsa,member = <0 0>;
+
+            ethernet-ports {
+                #address-cells = <1>;
+                #size-cells = <0>;
+
+                port@0 {
+                    reg = <0>;
+                    label = "cpu";
+                    ethernet = <&gmac0>;
+                };
+
+                port@2 {
+                    reg = <2>;
+                    label = "lan0";
+                    phy-handle = <&phy1>;
+                };
+
+                port@3 {
+                    reg = <3>;
+                    label = "lan1";
+                    phy-handle = <&phy2>;
+                };
+            };
+
+            leds {
+                #address-cells = <1>;
+                #size-cells = <0>;
+
+                led@0 {
+                    reg = <0>;
+                    label = "sync_good";
+                    default-state = "on";
+                };
+
+                led@1 {
+                    reg = <1>;
+                    label = "is_gm";
+                    default-state = "off";
+                };
+            };
+        };
--- a/Documentation/devicetree/bindings/vendor-prefixes.yaml
+++ b/Documentation/devicetree/bindings/vendor-prefixes.yaml
@ -441,6 +441,8 @@ patternProperties:
    description: HiDeep Inc.
  "^himax,.*":
    description: Himax Technologies, Inc.
+  "^hirschmann,.*":
+    description: Hirschmann Automation and Control GmbH
  "^hisilicon,.*":
    description: Hisilicon Limited.
  "^hit,.*":
--- a/drivers/net/dsa/Kconfig
+++ b/drivers/net/dsa/Kconfig
@ -24,6 +24,8 @@ config NET_DSA_LOOP
 	  This enables support for a fake mock-up switch chip which
 	  exercises the DSA APIs.

+source "drivers/net/dsa/hirschmann/Kconfig"
+
 config NET_DSA_LANTIQ_GSWIP
 	tristate "Lantiq / Intel GSWIP"
 	depends on HAS_IOMEM && NET_DSA
--- a/drivers/net/dsa/Makefile
+++ b/drivers/net/dsa/Makefile
@ -18,6 +18,7 @@ obj-$(CONFIG_NET_DSA_VITESSE_VSC73XX) += vitesse-vsc73xx-core.o
 obj-$(CONFIG_NET_DSA_VITESSE_VSC73XX_PLATFORM) += vitesse-vsc73xx-platform.o
 obj-$(CONFIG_NET_DSA_VITESSE_VSC73XX_SPI) += vitesse-vsc73xx-spi.o
 obj-y				+= b53/
+obj-y				+= hirschmann/
 obj-y				+= microchip/
 obj-y				+= mv88e6xxx/
 obj-y				+= ocelot/
--- a/drivers/net/dsa/hirschmann/Kconfig
+++ b/drivers/net/dsa/hirschmann/Kconfig
@ -0,0 +1,9 @@
+# SPDX-License-Identifier: GPL-2.0
+config NET_DSA_HIRSCHMANN_HELLCREEK
+	tristate "Hirschmann Hellcreek TSN Switch support"
+	depends on HAS_IOMEM
+	depends on NET_DSA
+	depends on PTP_1588_CLOCK
+	select NET_DSA_TAG_HELLCREEK
+	help
+	  This driver adds support for Hirschmann Hellcreek TSN switches.
--- a/drivers/net/dsa/hirschmann/Makefile
+++ b/drivers/net/dsa/hirschmann/Makefile
@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_NET_DSA_HIRSCHMANN_HELLCREEK)	+= hellcreek_sw.o
+hellcreek_sw-objs := hellcreek.o
+hellcreek_sw-objs += hellcreek_ptp.o
+hellcreek_sw-objs += hellcreek_hwtstamp.o
--- a/drivers/net/dsa/hirschmann/hellcreek.c
+++ b/drivers/net/dsa/hirschmann/hellcreek.c
--- a/drivers/net/dsa/hirschmann/hellcreek.h
+++ b/drivers/net/dsa/hirschmann/hellcreek.h
@ -0,0 +1,286 @@
+/* SPDX-License-Identifier: (GPL-2.0 or MIT) */
+/*
+ * DSA driver for:
+ * Hirschmann Hellcreek TSN switch.
+ *
+ * Copyright (C) 2019,2020 Linutronix GmbH
+ * Author Kurt Kanzenbach <kurt@linutronix.de>
+ */
+
+#ifndef _HELLCREEK_H_
+#define _HELLCREEK_H_
+
+#include <linux/bitmap.h>
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/mutex.h>
+#include <linux/workqueue.h>
+#include <linux/leds.h>
+#include <linux/platform_data/hirschmann-hellcreek.h>
+#include <linux/ptp_clock_kernel.h>
+#include <linux/timecounter.h>
+#include <net/dsa.h>
+
+/* Ports:
+ *  - 0: CPU
+ *  - 1: Tunnel
+ *  - 2: TSN front port 1
+ *  - 3: TSN front port 2
+ *  - ...
+ */
+#define CPU_PORT			0
+#define TUNNEL_PORT			1
+
+#define HELLCREEK_VLAN_NO_MEMBER	0x0
+#define HELLCREEK_VLAN_UNTAGGED_MEMBER	0x1
+#define HELLCREEK_VLAN_TAGGED_MEMBER	0x3
+#define HELLCREEK_NUM_EGRESS_QUEUES	8
+
+/* Register definitions */
+#define HR_MODID_C			(0 * 2)
+#define HR_REL_L_C			(1 * 2)
+#define HR_REL_H_C			(2 * 2)
+#define HR_BLD_L_C			(3 * 2)
+#define HR_BLD_H_C			(4 * 2)
+#define HR_CTRL_C			(5 * 2)
+#define HR_CTRL_C_READY			BIT(14)
+#define HR_CTRL_C_TRANSITION		BIT(13)
+#define HR_CTRL_C_ENABLE		BIT(0)
+
+#define HR_PSEL				(0xa6 * 2)
+#define HR_PSEL_PTWSEL_SHIFT		4
+#define HR_PSEL_PTWSEL_MASK		GENMASK(5, 4)
+#define HR_PSEL_PRTCWSEL_SHIFT		0
+#define HR_PSEL_PRTCWSEL_MASK		GENMASK(2, 0)
+
+#define HR_PTCFG			(0xa7 * 2)
+#define HR_PTCFG_MLIMIT_EN		BIT(13)
+#define HR_PTCFG_UMC_FLT		BIT(10)
+#define HR_PTCFG_UUC_FLT		BIT(9)
+#define HR_PTCFG_UNTRUST		BIT(8)
+#define HR_PTCFG_TAG_REQUIRED		BIT(7)
+#define HR_PTCFG_PPRIO_SHIFT		4
+#define HR_PTCFG_PPRIO_MASK		GENMASK(6, 4)
+#define HR_PTCFG_INGRESSFLT		BIT(3)
+#define HR_PTCFG_BLOCKED		BIT(2)
+#define HR_PTCFG_LEARNING_EN		BIT(1)
+#define HR_PTCFG_ADMIN_EN		BIT(0)
+
+#define HR_PRTCCFG			(0xa8 * 2)
+#define HR_PRTCCFG_PCP_TC_MAP_SHIFT	0
+#define HR_PRTCCFG_PCP_TC_MAP_MASK	GENMASK(2, 0)
+
+#define HR_CSEL				(0x8d * 2)
+#define HR_CSEL_SHIFT			0
+#define HR_CSEL_MASK			GENMASK(7, 0)
+#define HR_CRDL				(0x8e * 2)
+#define HR_CRDH				(0x8f * 2)
+
+#define HR_SWTRC_CFG			(0x90 * 2)
+#define HR_SWTRC0			(0x91 * 2)
+#define HR_SWTRC1			(0x92 * 2)
+#define HR_PFREE			(0x93 * 2)
+#define HR_MFREE			(0x94 * 2)
+
+#define HR_FDBAGE			(0x97 * 2)
+#define HR_FDBMAX			(0x98 * 2)
+#define HR_FDBRDL			(0x99 * 2)
+#define HR_FDBRDM			(0x9a * 2)
+#define HR_FDBRDH			(0x9b * 2)
+
+#define HR_FDBMDRD			(0x9c * 2)
+#define HR_FDBMDRD_PORTMASK_SHIFT	0
+#define HR_FDBMDRD_PORTMASK_MASK	GENMASK(3, 0)
+#define HR_FDBMDRD_AGE_SHIFT		4
+#define HR_FDBMDRD_AGE_MASK		GENMASK(7, 4)
+#define HR_FDBMDRD_OBT			BIT(8)
+#define HR_FDBMDRD_PASS_BLOCKED		BIT(9)
+#define HR_FDBMDRD_STATIC		BIT(11)
+#define HR_FDBMDRD_REPRIO_TC_SHIFT	12
+#define HR_FDBMDRD_REPRIO_TC_MASK	GENMASK(14, 12)
+#define HR_FDBMDRD_REPRIO_EN		BIT(15)
+
+#define HR_FDBWDL			(0x9d * 2)
+#define HR_FDBWDM			(0x9e * 2)
+#define HR_FDBWDH			(0x9f * 2)
+#define HR_FDBWRM0			(0xa0 * 2)
+#define HR_FDBWRM0_PORTMASK_SHIFT	0
+#define HR_FDBWRM0_PORTMASK_MASK	GENMASK(3, 0)
+#define HR_FDBWRM0_OBT			BIT(8)
+#define HR_FDBWRM0_PASS_BLOCKED		BIT(9)
+#define HR_FDBWRM0_REPRIO_TC_SHIFT	12
+#define HR_FDBWRM0_REPRIO_TC_MASK	GENMASK(14, 12)
+#define HR_FDBWRM0_REPRIO_EN		BIT(15)
+#define HR_FDBWRM1			(0xa1 * 2)
+
+#define HR_FDBWRCMD			(0xa2 * 2)
+#define HR_FDBWRCMD_FDBDEL		BIT(9)
+
+#define HR_SWCFG			(0xa3 * 2)
+#define HR_SWCFG_GM_STATEMD		BIT(15)
+#define HR_SWCFG_LAS_MODE_SHIFT		12
+#define HR_SWCFG_LAS_MODE_MASK		GENMASK(13, 12)
+#define HR_SWCFG_LAS_OFF		(0x00)
+#define HR_SWCFG_LAS_ON			(0x01)
+#define HR_SWCFG_LAS_STATIC		(0x10)
+#define HR_SWCFG_CT_EN			BIT(11)
+#define HR_SWCFG_VLAN_UNAWARE		BIT(10)
+#define HR_SWCFG_ALWAYS_OBT		BIT(9)
+#define HR_SWCFG_FDBAGE_EN		BIT(5)
+#define HR_SWCFG_FDBLRN_EN		BIT(4)
+
+#define HR_SWSTAT			(0xa4 * 2)
+#define HR_SWSTAT_FAIL			BIT(4)
+#define HR_SWSTAT_BUSY			BIT(0)
+
+#define HR_SWCMD			(0xa5 * 2)
+#define HW_SWCMD_FLUSH			BIT(0)
+
+#define HR_VIDCFG			(0xaa * 2)
+#define HR_VIDCFG_VID_SHIFT		0
+#define HR_VIDCFG_VID_MASK		GENMASK(11, 0)
+#define HR_VIDCFG_PVID			BIT(12)
+
+#define HR_VIDMBRCFG			(0xab * 2)
+#define HR_VIDMBRCFG_P0MBR_SHIFT	0
+#define HR_VIDMBRCFG_P0MBR_MASK		GENMASK(1, 0)
+#define HR_VIDMBRCFG_P1MBR_SHIFT	2
+#define HR_VIDMBRCFG_P1MBR_MASK		GENMASK(3, 2)
+#define HR_VIDMBRCFG_P2MBR_SHIFT	4
+#define HR_VIDMBRCFG_P2MBR_MASK		GENMASK(5, 4)
+#define HR_VIDMBRCFG_P3MBR_SHIFT	6
+#define HR_VIDMBRCFG_P3MBR_MASK		GENMASK(7, 6)
+
+#define HR_FEABITS0			(0xac * 2)
+#define HR_FEABITS0_FDBBINS_SHIFT	4
+#define HR_FEABITS0_FDBBINS_MASK	GENMASK(7, 4)
+#define HR_FEABITS0_PCNT_SHIFT		8
+#define HR_FEABITS0_PCNT_MASK		GENMASK(11, 8)
+#define HR_FEABITS0_MCNT_SHIFT		12
+#define HR_FEABITS0_MCNT_MASK		GENMASK(15, 12)
+
+#define TR_QTRACK			(0xb1 * 2)
+#define TR_TGDVER			(0xb3 * 2)
+#define TR_TGDVER_REV_MIN_MASK		GENMASK(7, 0)
+#define TR_TGDVER_REV_MIN_SHIFT		0
+#define TR_TGDVER_REV_MAJ_MASK		GENMASK(15, 8)
+#define TR_TGDVER_REV_MAJ_SHIFT		8
+#define TR_TGDSEL			(0xb4 * 2)
+#define TR_TGDSEL_TDGSEL_MASK		GENMASK(1, 0)
+#define TR_TGDSEL_TDGSEL_SHIFT		0
+#define TR_TGDCTRL			(0xb5 * 2)
+#define TR_TGDCTRL_GATE_EN		BIT(0)
+#define TR_TGDCTRL_CYC_SNAP		BIT(4)
+#define TR_TGDCTRL_SNAP_EST		BIT(5)
+#define TR_TGDCTRL_ADMINGATESTATES_MASK	GENMASK(15, 8)
+#define TR_TGDCTRL_ADMINGATESTATES_SHIFT	8
+#define TR_TGDSTAT0			(0xb6 * 2)
+#define TR_TGDSTAT1			(0xb7 * 2)
+#define TR_ESTWRL			(0xb8 * 2)
+#define TR_ESTWRH			(0xb9 * 2)
+#define TR_ESTCMD			(0xba * 2)
+#define TR_ESTCMD_ESTSEC_MASK		GENMASK(2, 0)
+#define TR_ESTCMD_ESTSEC_SHIFT		0
+#define TR_ESTCMD_ESTARM		BIT(4)
+#define TR_ESTCMD_ESTSWCFG		BIT(5)
+#define TR_EETWRL			(0xbb * 2)
+#define TR_EETWRH			(0xbc * 2)
+#define TR_EETCMD			(0xbd * 2)
+#define TR_EETCMD_EETSEC_MASK		GEMASK(2, 0)
+#define TR_EETCMD_EETSEC_SHIFT		0
+#define TR_EETCMD_EETARM		BIT(4)
+#define TR_CTWRL			(0xbe * 2)
+#define TR_CTWRH			(0xbf * 2)
+#define TR_LCNSL			(0xc1 * 2)
+#define TR_LCNSH			(0xc2 * 2)
+#define TR_LCS				(0xc3 * 2)
+#define TR_GCLDAT			(0xc4 * 2)
+#define TR_GCLDAT_GCLWRGATES_MASK	GENMASK(7, 0)
+#define TR_GCLDAT_GCLWRGATES_SHIFT	0
+#define TR_GCLDAT_GCLWRLAST		BIT(8)
+#define TR_GCLDAT_GCLOVRI		BIT(9)
+#define TR_GCLTIL			(0xc5 * 2)
+#define TR_GCLTIH			(0xc6 * 2)
+#define TR_GCLCMD			(0xc7 * 2)
+#define TR_GCLCMD_GCLWRADR_MASK		GENMASK(7, 0)
+#define TR_GCLCMD_GCLWRADR_SHIFT	0
+#define TR_GCLCMD_INIT_GATE_STATES_MASK	GENMASK(15, 8)
+#define TR_GCLCMD_INIT_GATE_STATES_SHIFT	8
+
+struct hellcreek_counter {
+	u8 offset;
+	const char *name;
+};
+
+struct hellcreek;
+
+/* State flags for hellcreek_port_hwtstamp::state */
+enum {
+	HELLCREEK_HWTSTAMP_ENABLED,
+	HELLCREEK_HWTSTAMP_TX_IN_PROGRESS,
+};
+
+/* A structure to hold hardware timestamping information per port */
+struct hellcreek_port_hwtstamp {
+	/* Timestamping state */
+	unsigned long state;
+
+	/* Resources for receive timestamping */
+	struct sk_buff_head rx_queue; /* For synchronization messages */
+
+	/* Resources for transmit timestamping */
+	unsigned long tx_tstamp_start;
+	struct sk_buff *tx_skb;
+
+	/* Current timestamp configuration */
+	struct hwtstamp_config tstamp_config;
+};
+
+struct hellcreek_port {
+	struct hellcreek *hellcreek;
+	unsigned long *vlan_dev_bitmap;
+	int port;
+	u16 ptcfg;		/* ptcfg shadow */
+	u64 *counter_values;
+
+	/* Per-port timestamping resources */
+	struct hellcreek_port_hwtstamp port_hwtstamp;
+};
+
+struct hellcreek_fdb_entry {
+	size_t idx;
+	unsigned char mac[ETH_ALEN];
+	u8 portmask;
+	u8 age;
+	u8 is_obt;
+	u8 pass_blocked;
+	u8 is_static;
+	u8 reprio_tc;
+	u8 reprio_en;
+};
+
+struct hellcreek {
+	const struct hellcreek_platform_data *pdata;
+	struct device *dev;
+	struct dsa_switch *ds;
+	struct ptp_clock *ptp_clock;
+	struct ptp_clock_info ptp_clock_info;
+	struct hellcreek_port *ports;
+	struct delayed_work overflow_work;
+	struct led_classdev led_is_gm;
+	struct led_classdev led_sync_good;
+	struct mutex reg_lock;	/* Switch IP register lock */
+	struct mutex vlan_lock;	/* VLAN bitmaps lock */
+	struct mutex ptp_lock;	/* PTP IP register lock */
+	void __iomem *base;
+	void __iomem *ptp_base;
+	u16 swcfg;		/* swcfg shadow */
+	u8 *vidmbrcfg;		/* vidmbrcfg shadow */
+	u64 seconds;		/* PTP seconds */
+	u64 last_ts;		/* Used for overflow detection */
+	u16 status_out;		/* ptp.status_out shadow */
+	size_t fdb_entries;
+};
+
+#endif /* _HELLCREEK_H_ */
--- a/drivers/net/dsa/hirschmann/hellcreek_hwtstamp.c
+++ b/drivers/net/dsa/hirschmann/hellcreek_hwtstamp.c
@ -0,0 +1,479 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/*
+ * DSA driver for:
+ * Hirschmann Hellcreek TSN switch.
+ *
+ * Copyright (C) 2019,2020 Hochschule Offenburg
+ * Copyright (C) 2019,2020 Linutronix GmbH
+ * Authors: Kamil Alkhouri <kamil.alkhouri@hs-offenburg.de>
+ *	    Kurt Kanzenbach <kurt@linutronix.de>
+ */
+
+#include <linux/ptp_classify.h>
+
+#include "hellcreek.h"
+#include "hellcreek_hwtstamp.h"
+#include "hellcreek_ptp.h"
+
+int hellcreek_get_ts_info(struct dsa_switch *ds, int port,
+			  struct ethtool_ts_info *info)
+{
+	struct hellcreek *hellcreek = ds->priv;
+
+	info->phc_index = hellcreek->ptp_clock ?
+		ptp_clock_index(hellcreek->ptp_clock) : -1;
+	info->so_timestamping = SOF_TIMESTAMPING_TX_HARDWARE |
+		SOF_TIMESTAMPING_RX_HARDWARE |
+		SOF_TIMESTAMPING_RAW_HARDWARE;
+
+	/* enabled tx timestamping */
+	info->tx_types = BIT(HWTSTAMP_TX_ON);
+
+	/* L2 & L4 PTPv2 event rx messages are timestamped */
+	info->rx_filters = BIT(HWTSTAMP_FILTER_PTP_V2_EVENT);
+
+	return 0;
+}
+
+/* Enabling/disabling TX and RX HW timestamping for different PTP messages is
+ * not available in the switch. Thus, this function only serves as a check if
+ * the user requested what is actually available or not
+ */
+static int hellcreek_set_hwtstamp_config(struct hellcreek *hellcreek, int port,
+					 struct hwtstamp_config *config)
+{
+	struct hellcreek_port_hwtstamp *ps =
+		&hellcreek->ports[port].port_hwtstamp;
+	bool tx_tstamp_enable = false;
+	bool rx_tstamp_enable = false;
+
+	/* Interaction with the timestamp hardware is prevented here.  It is
+	 * enabled when this config function ends successfully
+	 */
+	clear_bit_unlock(HELLCREEK_HWTSTAMP_ENABLED, &ps->state);
+
+	/* Reserved for future extensions */
+	if (config->flags)
+		return -EINVAL;
+
+	switch (config->tx_type) {
+	case HWTSTAMP_TX_ON:
+		tx_tstamp_enable = true;
+		break;
+
+	/* TX HW timestamping can't be disabled on the switch */
+	case HWTSTAMP_TX_OFF:
+		config->tx_type = HWTSTAMP_TX_ON;
+		break;
+
+	default:
+		return -ERANGE;
+	}
+
+	switch (config->rx_filter) {
+	/* RX HW timestamping can't be disabled on the switch */
+	case HWTSTAMP_FILTER_NONE:
+		config->rx_filter = HWTSTAMP_FILTER_PTP_V2_EVENT;
+		break;
+
+	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
+	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
+	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
+	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
+	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
+	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
+	case HWTSTAMP_FILTER_PTP_V2_EVENT:
+	case HWTSTAMP_FILTER_PTP_V2_SYNC:
+	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
+		config->rx_filter = HWTSTAMP_FILTER_PTP_V2_EVENT;
+		rx_tstamp_enable = true;
+		break;
+
+	/* RX HW timestamping can't be enabled for all messages on the switch */
+	case HWTSTAMP_FILTER_ALL:
+		config->rx_filter = HWTSTAMP_FILTER_PTP_V2_EVENT;
+		break;
+
+	default:
+		return -ERANGE;
+	}
+
+	if (!tx_tstamp_enable)
+		return -ERANGE;
+
+	if (!rx_tstamp_enable)
+		return -ERANGE;
+
+	/* If this point is reached, then the requested hwtstamp config is
+	 * compatible with the hwtstamp offered by the switch.  Therefore,
+	 * enable the interaction with the HW timestamping
+	 */
+	set_bit(HELLCREEK_HWTSTAMP_ENABLED, &ps->state);
+
+	return 0;
+}
+
+int hellcreek_port_hwtstamp_set(struct dsa_switch *ds, int port,
+				struct ifreq *ifr)
+{
+	struct hellcreek *hellcreek = ds->priv;
+	struct hellcreek_port_hwtstamp *ps;
+	struct hwtstamp_config config;
+	int err;
+
+	ps = &hellcreek->ports[port].port_hwtstamp;
+
+	if (copy_from_user(&config, ifr->ifr_data, sizeof(config)))
+		return -EFAULT;
+
+	err = hellcreek_set_hwtstamp_config(hellcreek, port, &config);
+	if (err)
+		return err;
+
+	/* Save the chosen configuration to be returned later */
+	memcpy(&ps->tstamp_config, &config, sizeof(config));
+
+	return copy_to_user(ifr->ifr_data, &config, sizeof(config)) ?
+		-EFAULT : 0;
+}
+
+int hellcreek_port_hwtstamp_get(struct dsa_switch *ds, int port,
+				struct ifreq *ifr)
+{
+	struct hellcreek *hellcreek = ds->priv;
+	struct hellcreek_port_hwtstamp *ps;
+	struct hwtstamp_config *config;
+
+	ps = &hellcreek->ports[port].port_hwtstamp;
+	config = &ps->tstamp_config;
+
+	return copy_to_user(ifr->ifr_data, config, sizeof(*config)) ?
+		-EFAULT : 0;
+}
+
+/* Returns a pointer to the PTP header if the caller should time stamp, or NULL
+ * if the caller should not.
+ */
+static struct ptp_header *hellcreek_should_tstamp(struct hellcreek *hellcreek,
+						  int port, struct sk_buff *skb,
+						  unsigned int type)
+{
+	struct hellcreek_port_hwtstamp *ps =
+		&hellcreek->ports[port].port_hwtstamp;
+	struct ptp_header *hdr;
+
+	hdr = ptp_parse_header(skb, type);
+	if (!hdr)
+		return NULL;
+
+	if (!test_bit(HELLCREEK_HWTSTAMP_ENABLED, &ps->state))
+		return NULL;
+
+	return hdr;
+}
+
+static u64 hellcreek_get_reserved_field(const struct ptp_header *hdr)
+{
+	return be32_to_cpu(hdr->reserved2);
+}
+
+static void hellcreek_clear_reserved_field(struct ptp_header *hdr)
+{
+	hdr->reserved2 = 0;
+}
+
+static int hellcreek_ptp_hwtstamp_available(struct hellcreek *hellcreek,
+					    unsigned int ts_reg)
+{
+	u16 status;
+
+	status = hellcreek_ptp_read(hellcreek, ts_reg);
+
+	if (status & PR_TS_STATUS_TS_LOST)
+		dev_err(hellcreek->dev,
+			"Tx time stamp lost! This should never happen!\n");
+
+	/* If hwtstamp is not available, this means the previous hwtstamp was
+	 * successfully read, and the one we need is not yet available
+	 */
+	return (status & PR_TS_STATUS_TS_AVAIL) ? 1 : 0;
+}
+
+/* Get nanoseconds timestamp from timestamping unit */
+static u64 hellcreek_ptp_hwtstamp_read(struct hellcreek *hellcreek,
+				       unsigned int ts_reg)
+{
+	u16 nsl, nsh;
+
+	nsh = hellcreek_ptp_read(hellcreek, ts_reg);
+	nsh = hellcreek_ptp_read(hellcreek, ts_reg);
+	nsh = hellcreek_ptp_read(hellcreek, ts_reg);
+	nsh = hellcreek_ptp_read(hellcreek, ts_reg);
+	nsl = hellcreek_ptp_read(hellcreek, ts_reg);
+
+	return (u64)nsl | ((u64)nsh << 16);
+}
+
+static int hellcreek_txtstamp_work(struct hellcreek *hellcreek,
+				   struct hellcreek_port_hwtstamp *ps, int port)
+{
+	struct skb_shared_hwtstamps shhwtstamps;
+	unsigned int status_reg, data_reg;
+	struct sk_buff *tmp_skb;
+	int ts_status;
+	u64 ns = 0;
+
+	if (!ps->tx_skb)
+		return 0;
+
+	switch (port) {
+	case 2:
+		status_reg = PR_TS_TX_P1_STATUS_C;
+		data_reg   = PR_TS_TX_P1_DATA_C;
+		break;
+	case 3:
+		status_reg = PR_TS_TX_P2_STATUS_C;
+		data_reg   = PR_TS_TX_P2_DATA_C;
+		break;
+	default:
+		dev_err(hellcreek->dev, "Wrong port for timestamping!\n");
+		return 0;
+	}
+
+	ts_status = hellcreek_ptp_hwtstamp_available(hellcreek, status_reg);
+
+	/* Not available yet? */
+	if (ts_status == 0) {
+		/* Check whether the operation of reading the tx timestamp has
+		 * exceeded its allowed period
+		 */
+		if (time_is_before_jiffies(ps->tx_tstamp_start +
+					   TX_TSTAMP_TIMEOUT)) {
+			dev_err(hellcreek->dev,
+				"Timeout while waiting for Tx timestamp!\n");
+			goto free_and_clear_skb;
+		}
+
+		/* The timestamp should be available quickly, while getting it
+		 * in high priority. Restart the work
+		 */
+		return 1;
+	}
+
+	mutex_lock(&hellcreek->ptp_lock);
+	ns  = hellcreek_ptp_hwtstamp_read(hellcreek, data_reg);
+	ns += hellcreek_ptp_gettime_seconds(hellcreek, ns);
+	mutex_unlock(&hellcreek->ptp_lock);
+
+	/* Now we have the timestamp in nanoseconds, store it in the correct
+	 * structure in order to send it to the user
+	 */
+	memset(&shhwtstamps, 0, sizeof(shhwtstamps));
+	shhwtstamps.hwtstamp = ns_to_ktime(ns);
+
+	tmp_skb = ps->tx_skb;
+	ps->tx_skb = NULL;
+
+	/* skb_complete_tx_timestamp() frees up the client to make another
+	 * timestampable transmit.  We have to be ready for it by clearing the
+	 * ps->tx_skb "flag" beforehand
+	 */
+	clear_bit_unlock(HELLCREEK_HWTSTAMP_TX_IN_PROGRESS, &ps->state);
+
+	/* Deliver a clone of the original outgoing tx_skb with tx hwtstamp */
+	skb_complete_tx_timestamp(tmp_skb, &shhwtstamps);
+
+	return 0;
+
+free_and_clear_skb:
+	dev_kfree_skb_any(ps->tx_skb);
+	ps->tx_skb = NULL;
+	clear_bit_unlock(HELLCREEK_HWTSTAMP_TX_IN_PROGRESS, &ps->state);
+
+	return 0;
+}
+
+static void hellcreek_get_rxts(struct hellcreek *hellcreek,
+			       struct hellcreek_port_hwtstamp *ps,
+			       struct sk_buff *skb, struct sk_buff_head *rxq,
+			       int port)
+{
+	struct skb_shared_hwtstamps *shwt;
+	struct sk_buff_head received;
+	unsigned long flags;
+
+	/* The latched timestamp belongs to one of the received frames. */
+	__skb_queue_head_init(&received);
+
+	/* Lock & disable interrupts */
+	spin_lock_irqsave(&rxq->lock, flags);
+
+	/* Add the reception queue "rxq" to the "received" queue an reintialize
+	 * "rxq".  From now on, we deal with "received" not with "rxq"
+	 */
+	skb_queue_splice_tail_init(rxq, &received);
+
+	spin_unlock_irqrestore(&rxq->lock, flags);
+
+	for (; skb; skb = __skb_dequeue(&received)) {
+		struct ptp_header *hdr;
+		unsigned int type;
+		u64 ns;
+
+		/* Get nanoseconds from ptp packet */
+		type = SKB_PTP_TYPE(skb);
+		hdr  = ptp_parse_header(skb, type);
+		ns   = hellcreek_get_reserved_field(hdr);
+		hellcreek_clear_reserved_field(hdr);
+
+		/* Add seconds part */
+		mutex_lock(&hellcreek->ptp_lock);
+		ns += hellcreek_ptp_gettime_seconds(hellcreek, ns);
+		mutex_unlock(&hellcreek->ptp_lock);
+
+		/* Save time stamp */
+		shwt = skb_hwtstamps(skb);
+		memset(shwt, 0, sizeof(*shwt));
+		shwt->hwtstamp = ns_to_ktime(ns);
+		netif_rx_ni(skb);
+	}
+}
+
+static void hellcreek_rxtstamp_work(struct hellcreek *hellcreek,
+				    struct hellcreek_port_hwtstamp *ps,
+				    int port)
+{
+	struct sk_buff *skb;
+
+	skb = skb_dequeue(&ps->rx_queue);
+	if (skb)
+		hellcreek_get_rxts(hellcreek, ps, skb, &ps->rx_queue, port);
+}
+
+long hellcreek_hwtstamp_work(struct ptp_clock_info *ptp)
+{
+	struct hellcreek *hellcreek = ptp_to_hellcreek(ptp);
+	struct dsa_switch *ds = hellcreek->ds;
+	int i, restart = 0;
+
+	for (i = 0; i < ds->num_ports; i++) {
+		struct hellcreek_port_hwtstamp *ps;
+
+		if (!dsa_is_user_port(ds, i))
+			continue;
+
+		ps = &hellcreek->ports[i].port_hwtstamp;
+
+		if (test_bit(HELLCREEK_HWTSTAMP_TX_IN_PROGRESS, &ps->state))
+			restart |= hellcreek_txtstamp_work(hellcreek, ps, i);
+
+		hellcreek_rxtstamp_work(hellcreek, ps, i);
+	}
+
+	return restart ? 1 : -1;
+}
+
+bool hellcreek_port_txtstamp(struct dsa_switch *ds, int port,
+			     struct sk_buff *clone, unsigned int type)
+{
+	struct hellcreek *hellcreek = ds->priv;
+	struct hellcreek_port_hwtstamp *ps;
+	struct ptp_header *hdr;
+
+	ps = &hellcreek->ports[port].port_hwtstamp;
+
+	/* Check if the driver is expected to do HW timestamping */
+	if (!(skb_shinfo(clone)->tx_flags & SKBTX_HW_TSTAMP))
+		return false;
+
+	/* Make sure the message is a PTP message that needs to be timestamped
+	 * and the interaction with the HW timestamping is enabled. If not, stop
+	 * here
+	 */
+	hdr = hellcreek_should_tstamp(hellcreek, port, clone, type);
+	if (!hdr)
+		return false;
+
+	if (test_and_set_bit_lock(HELLCREEK_HWTSTAMP_TX_IN_PROGRESS,
+				  &ps->state))
+		return false;
+
+	ps->tx_skb = clone;
+
+	/* store the number of ticks occurred since system start-up till this
+	 * moment
+	 */
+	ps->tx_tstamp_start = jiffies;
+
+	ptp_schedule_worker(hellcreek->ptp_clock, 0);
+
+	return true;
+}
+
+bool hellcreek_port_rxtstamp(struct dsa_switch *ds, int port,
+			     struct sk_buff *skb, unsigned int type)
+{
+	struct hellcreek *hellcreek = ds->priv;
+	struct hellcreek_port_hwtstamp *ps;
+	struct ptp_header *hdr;
+
+	ps = &hellcreek->ports[port].port_hwtstamp;
+
+	/* This check only fails if the user did not initialize hardware
+	 * timestamping beforehand.
+	 */
+	if (ps->tstamp_config.rx_filter != HWTSTAMP_FILTER_PTP_V2_EVENT)
+		return false;
+
+	/* Make sure the message is a PTP message that needs to be timestamped
+	 * and the interaction with the HW timestamping is enabled. If not, stop
+	 * here
+	 */
+	hdr = hellcreek_should_tstamp(hellcreek, port, skb, type);
+	if (!hdr)
+		return false;
+
+	SKB_PTP_TYPE(skb) = type;
+
+	skb_queue_tail(&ps->rx_queue, skb);
+
+	ptp_schedule_worker(hellcreek->ptp_clock, 0);
+
+	return true;
+}
+
+static void hellcreek_hwtstamp_port_setup(struct hellcreek *hellcreek, int port)
+{
+	struct hellcreek_port_hwtstamp *ps =
+		&hellcreek->ports[port].port_hwtstamp;
+
+	skb_queue_head_init(&ps->rx_queue);
+}
+
+int hellcreek_hwtstamp_setup(struct hellcreek *hellcreek)
+{
+	struct dsa_switch *ds = hellcreek->ds;
+	int i;
+
+	/* Initialize timestamping ports. */
+	for (i = 0; i < ds->num_ports; ++i) {
+		if (!dsa_is_user_port(ds, i))
+			continue;
+
+		hellcreek_hwtstamp_port_setup(hellcreek, i);
+	}
+
+	/* Select the synchronized clock as the source timekeeper for the
+	 * timestamps and enable inline timestamping.
+	 */
+	hellcreek_ptp_write(hellcreek, PR_SETTINGS_C_TS_SRC_TK_MASK |
+			    PR_SETTINGS_C_RES3TS,
+			    PR_SETTINGS_C);
+
+	return 0;
+}
+
+void hellcreek_hwtstamp_free(struct hellcreek *hellcreek)
+{
+	/* Nothing todo */
+}
--- a/drivers/net/dsa/hirschmann/hellcreek_hwtstamp.h
+++ b/drivers/net/dsa/hirschmann/hellcreek_hwtstamp.h
@ -0,0 +1,58 @@
+/* SPDX-License-Identifier: (GPL-2.0 OR MIT) */
+/*
+ * DSA driver for:
+ * Hirschmann Hellcreek TSN switch.
+ *
+ * Copyright (C) 2019,2020 Hochschule Offenburg
+ * Copyright (C) 2019,2020 Linutronix GmbH
+ * Authors: Kurt Kanzenbach <kurt@linutronix.de>
+ *	    Kamil Alkhouri <kamil.alkhouri@hs-offenburg.de>
+ */
+
+#ifndef _HELLCREEK_HWTSTAMP_H_
+#define _HELLCREEK_HWTSTAMP_H_
+
+#include <net/dsa.h>
+#include "hellcreek.h"
+
+/* Timestamp Register */
+#define PR_TS_RX_P1_STATUS_C	(0x1d * 2)
+#define PR_TS_RX_P1_DATA_C	(0x1e * 2)
+#define PR_TS_TX_P1_STATUS_C	(0x1f * 2)
+#define PR_TS_TX_P1_DATA_C	(0x20 * 2)
+#define PR_TS_RX_P2_STATUS_C	(0x25 * 2)
+#define PR_TS_RX_P2_DATA_C	(0x26 * 2)
+#define PR_TS_TX_P2_STATUS_C	(0x27 * 2)
+#define PR_TS_TX_P2_DATA_C	(0x28 * 2)
+
+#define PR_TS_STATUS_TS_AVAIL	BIT(2)
+#define PR_TS_STATUS_TS_LOST	BIT(3)
+
+#define SKB_PTP_TYPE(__skb) (*(unsigned int *)((__skb)->cb))
+
+/* TX_TSTAMP_TIMEOUT: This limits the time spent polling for a TX
+ * timestamp. When working properly, hardware will produce a timestamp
+ * within 1ms. Software may enounter delays, so the timeout is set
+ * accordingly.
+ */
+#define TX_TSTAMP_TIMEOUT	msecs_to_jiffies(40)
+
+int hellcreek_port_hwtstamp_set(struct dsa_switch *ds, int port,
+				struct ifreq *ifr);
+int hellcreek_port_hwtstamp_get(struct dsa_switch *ds, int port,
+				struct ifreq *ifr);
+
+bool hellcreek_port_rxtstamp(struct dsa_switch *ds, int port,
+			     struct sk_buff *clone, unsigned int type);
+bool hellcreek_port_txtstamp(struct dsa_switch *ds, int port,
+			     struct sk_buff *clone, unsigned int type);
+
+int hellcreek_get_ts_info(struct dsa_switch *ds, int port,
+			  struct ethtool_ts_info *info);
+
+long hellcreek_hwtstamp_work(struct ptp_clock_info *ptp);
+
+int hellcreek_hwtstamp_setup(struct hellcreek *chip);
+void hellcreek_hwtstamp_free(struct hellcreek *chip);
+
+#endif /* _HELLCREEK_HWTSTAMP_H_ */
--- a/drivers/net/dsa/hirschmann/hellcreek_ptp.c
+++ b/drivers/net/dsa/hirschmann/hellcreek_ptp.c
@ -0,0 +1,452 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/*
+ * DSA driver for:
+ * Hirschmann Hellcreek TSN switch.
+ *
+ * Copyright (C) 2019,2020 Hochschule Offenburg
+ * Copyright (C) 2019,2020 Linutronix GmbH
+ * Authors: Kamil Alkhouri <kamil.alkhouri@hs-offenburg.de>
+ *	    Kurt Kanzenbach <kurt@linutronix.de>
+ */
+
+#include <linux/ptp_clock_kernel.h>
+#include "hellcreek.h"
+#include "hellcreek_ptp.h"
+#include "hellcreek_hwtstamp.h"
+
+u16 hellcreek_ptp_read(struct hellcreek *hellcreek, unsigned int offset)
+{
+	return readw(hellcreek->ptp_base + offset);
+}
+
+void hellcreek_ptp_write(struct hellcreek *hellcreek, u16 data,
+			 unsigned int offset)
+{
+	writew(data, hellcreek->ptp_base + offset);
+}
+
+/* Get nanoseconds from PTP clock */
+static u64 hellcreek_ptp_clock_read(struct hellcreek *hellcreek)
+{
+	u16 nsl, nsh;
+
+	/* Take a snapshot */
+	hellcreek_ptp_write(hellcreek, PR_COMMAND_C_SS, PR_COMMAND_C);
+
+	/* The time of the day is saved as 96 bits. However, due to hardware
+	 * limitations the seconds are not or only partly kept in the PTP
+	 * core. Currently only three bits for the seconds are available. That's
+	 * why only the nanoseconds are used and the seconds are tracked in
+	 * software. Anyway due to internal locking all five registers should be
+	 * read.
+	 */
+	nsh = hellcreek_ptp_read(hellcreek, PR_SS_SYNC_DATA_C);
+	nsh = hellcreek_ptp_read(hellcreek, PR_SS_SYNC_DATA_C);
+	nsh = hellcreek_ptp_read(hellcreek, PR_SS_SYNC_DATA_C);
+	nsh = hellcreek_ptp_read(hellcreek, PR_SS_SYNC_DATA_C);
+	nsl = hellcreek_ptp_read(hellcreek, PR_SS_SYNC_DATA_C);
+
+	return (u64)nsl | ((u64)nsh << 16);
+}
+
+static u64 __hellcreek_ptp_gettime(struct hellcreek *hellcreek)
+{
+	u64 ns;
+
+	ns = hellcreek_ptp_clock_read(hellcreek);
+	if (ns < hellcreek->last_ts)
+		hellcreek->seconds++;
+	hellcreek->last_ts = ns;
+	ns += hellcreek->seconds * NSEC_PER_SEC;
+
+	return ns;
+}
+
+/* Retrieve the seconds parts in nanoseconds for a packet timestamped with @ns.
+ * There has to be a check whether an overflow occurred between the packet
+ * arrival and now. If so use the correct seconds (-1) for calculating the
+ * packet arrival time.
+ */
+u64 hellcreek_ptp_gettime_seconds(struct hellcreek *hellcreek, u64 ns)
+{
+	u64 s;
+
+	__hellcreek_ptp_gettime(hellcreek);
+	if (hellcreek->last_ts > ns)
+		s = hellcreek->seconds * NSEC_PER_SEC;
+	else
+		s = (hellcreek->seconds - 1) * NSEC_PER_SEC;
+
+	return s;
+}
+
+static int hellcreek_ptp_gettime(struct ptp_clock_info *ptp,
+				 struct timespec64 *ts)
+{
+	struct hellcreek *hellcreek = ptp_to_hellcreek(ptp);
+	u64 ns;
+
+	mutex_lock(&hellcreek->ptp_lock);
+	ns = __hellcreek_ptp_gettime(hellcreek);
+	mutex_unlock(&hellcreek->ptp_lock);
+
+	*ts = ns_to_timespec64(ns);
+
+	return 0;
+}
+
+static int hellcreek_ptp_settime(struct ptp_clock_info *ptp,
+				 const struct timespec64 *ts)
+{
+	struct hellcreek *hellcreek = ptp_to_hellcreek(ptp);
+	u16 secl, nsh, nsl;
+
+	secl = ts->tv_sec & 0xffff;
+	nsh  = ((u32)ts->tv_nsec & 0xffff0000) >> 16;
+	nsl  = ts->tv_nsec & 0xffff;
+
+	mutex_lock(&hellcreek->ptp_lock);
+
+	/* Update overflow data structure */
+	hellcreek->seconds = ts->tv_sec;
+	hellcreek->last_ts = ts->tv_nsec;
+
+	/* Set time in clock */
+	hellcreek_ptp_write(hellcreek, 0x00, PR_CLOCK_WRITE_C);
+	hellcreek_ptp_write(hellcreek, 0x00, PR_CLOCK_WRITE_C);
+	hellcreek_ptp_write(hellcreek, secl, PR_CLOCK_WRITE_C);
+	hellcreek_ptp_write(hellcreek, nsh,  PR_CLOCK_WRITE_C);
+	hellcreek_ptp_write(hellcreek, nsl,  PR_CLOCK_WRITE_C);
+
+	mutex_unlock(&hellcreek->ptp_lock);
+
+	return 0;
+}
+
+static int hellcreek_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
+{
+	struct hellcreek *hellcreek = ptp_to_hellcreek(ptp);
+	u16 negative = 0, addendh, addendl;
+	u32 addend;
+	u64 adj;
+
+	if (scaled_ppm < 0) {
+		negative = 1;
+		scaled_ppm = -scaled_ppm;
+	}
+
+	/* IP-Core adjusts the nominal frequency by adding or subtracting 1 ns
+	 * from the 8 ns (period of the oscillator) every time the accumulator
+	 * register overflows. The value stored in the addend register is added
+	 * to the accumulator register every 8 ns.
+	 *
+	 * addend value = (2^30 * accumulator_overflow_rate) /
+	 *                oscillator_frequency
+	 * where:
+	 *
+	 * oscillator_frequency = 125 MHz
+	 * accumulator_overflow_rate = 125 MHz * scaled_ppm * 2^-16 * 10^-6 * 8
+	 */
+	adj = scaled_ppm;
+	adj <<= 11;
+	addend = (u32)div_u64(adj, 15625);
+
+	addendh = (addend & 0xffff0000) >> 16;
+	addendl = addend & 0xffff;
+
+	negative = (negative << 15) & 0x8000;
+
+	mutex_lock(&hellcreek->ptp_lock);
+
+	/* Set drift register */
+	hellcreek_ptp_write(hellcreek, negative, PR_CLOCK_DRIFT_C);
+	hellcreek_ptp_write(hellcreek, 0x00, PR_CLOCK_DRIFT_C);
+	hellcreek_ptp_write(hellcreek, 0x00, PR_CLOCK_DRIFT_C);
+	hellcreek_ptp_write(hellcreek, addendh,  PR_CLOCK_DRIFT_C);
+	hellcreek_ptp_write(hellcreek, addendl,  PR_CLOCK_DRIFT_C);
+
+	mutex_unlock(&hellcreek->ptp_lock);
+
+	return 0;
+}
+
+static int hellcreek_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
+{
+	struct hellcreek *hellcreek = ptp_to_hellcreek(ptp);
+	u16 negative = 0, counth, countl;
+	u32 count_val;
+
+	/* If the offset is larger than IP-Core slow offset resources. Don't
+	 * consider slow adjustment. Rather, add the offset directly to the
+	 * current time
+	 */
+	if (abs(delta) > MAX_SLOW_OFFSET_ADJ) {
+		struct timespec64 now, then = ns_to_timespec64(delta);
+
+		hellcreek_ptp_gettime(ptp, &now);
+		now = timespec64_add(now, then);
+		hellcreek_ptp_settime(ptp, &now);
+
+		return 0;
+	}
+
+	if (delta < 0) {
+		negative = 1;
+		delta = -delta;
+	}
+
+	/* 'count_val' does not exceed the maximum register size (2^30) */
+	count_val = div_s64(delta, MAX_NS_PER_STEP);
+
+	counth = (count_val & 0xffff0000) >> 16;
+	countl = count_val & 0xffff;
+
+	negative = (negative << 15) & 0x8000;
+
+	mutex_lock(&hellcreek->ptp_lock);
+
+	/* Set offset write register */
+	hellcreek_ptp_write(hellcreek, negative, PR_CLOCK_OFFSET_C);
+	hellcreek_ptp_write(hellcreek, MAX_NS_PER_STEP, PR_CLOCK_OFFSET_C);
+	hellcreek_ptp_write(hellcreek, MIN_CLK_CYCLES_BETWEEN_STEPS,
+			    PR_CLOCK_OFFSET_C);
+	hellcreek_ptp_write(hellcreek, countl,  PR_CLOCK_OFFSET_C);
+	hellcreek_ptp_write(hellcreek, counth,  PR_CLOCK_OFFSET_C);
+
+	mutex_unlock(&hellcreek->ptp_lock);
+
+	return 0;
+}
+
+static int hellcreek_ptp_enable(struct ptp_clock_info *ptp,
+				struct ptp_clock_request *rq, int on)
+{
+	return -EOPNOTSUPP;
+}
+
+static void hellcreek_ptp_overflow_check(struct work_struct *work)
+{
+	struct delayed_work *dw = to_delayed_work(work);
+	struct hellcreek *hellcreek;
+
+	hellcreek = dw_overflow_to_hellcreek(dw);
+
+	mutex_lock(&hellcreek->ptp_lock);
+	__hellcreek_ptp_gettime(hellcreek);
+	mutex_unlock(&hellcreek->ptp_lock);
+
+	schedule_delayed_work(&hellcreek->overflow_work,
+			      HELLCREEK_OVERFLOW_PERIOD);
+}
+
+static enum led_brightness hellcreek_get_brightness(struct hellcreek *hellcreek,
+						    int led)
+{
+	return (hellcreek->status_out & led) ? 1 : 0;
+}
+
+static void hellcreek_set_brightness(struct hellcreek *hellcreek, int led,
+				     enum led_brightness b)
+{
+	mutex_lock(&hellcreek->ptp_lock);
+
+	if (b)
+		hellcreek->status_out |= led;
+	else
+		hellcreek->status_out &= ~led;
+
+	hellcreek_ptp_write(hellcreek, hellcreek->status_out, STATUS_OUT);
+
+	mutex_unlock(&hellcreek->ptp_lock);
+}
+
+static void hellcreek_led_sync_good_set(struct led_classdev *ldev,
+					enum led_brightness b)
+{
+	struct hellcreek *hellcreek = led_to_hellcreek(ldev, led_sync_good);
+
+	hellcreek_set_brightness(hellcreek, STATUS_OUT_SYNC_GOOD, b);
+}
+
+static enum led_brightness hellcreek_led_sync_good_get(struct led_classdev *ldev)
+{
+	struct hellcreek *hellcreek = led_to_hellcreek(ldev, led_sync_good);
+
+	return hellcreek_get_brightness(hellcreek, STATUS_OUT_SYNC_GOOD);
+}
+
+static void hellcreek_led_is_gm_set(struct led_classdev *ldev,
+				    enum led_brightness b)
+{
+	struct hellcreek *hellcreek = led_to_hellcreek(ldev, led_is_gm);
+
+	hellcreek_set_brightness(hellcreek, STATUS_OUT_IS_GM, b);
+}
+
+static enum led_brightness hellcreek_led_is_gm_get(struct led_classdev *ldev)
+{
+	struct hellcreek *hellcreek = led_to_hellcreek(ldev, led_is_gm);
+
+	return hellcreek_get_brightness(hellcreek, STATUS_OUT_IS_GM);
+}
+
+/* There two available LEDs internally called sync_good and is_gm. However, the
+ * user might want to use a different label and specify the default state. Take
+ * those properties from device tree.
+ */
+static int hellcreek_led_setup(struct hellcreek *hellcreek)
+{
+	struct device_node *leds, *led = NULL;
+	const char *label, *state;
+	int ret = -EINVAL;
+
+	leds = of_find_node_by_name(hellcreek->dev->of_node, "leds");
+	if (!leds) {
+		dev_err(hellcreek->dev, "No LEDs specified in device tree!\n");
+		return ret;
+	}
+
+	hellcreek->status_out = 0;
+
+	led = of_get_next_available_child(leds, led);
+	if (!led) {
+		dev_err(hellcreek->dev, "First LED not specified!\n");
+		goto out;
+	}
+
+	ret = of_property_read_string(led, "label", &label);
+	hellcreek->led_sync_good.name = ret ? "sync_good" : label;
+
+	ret = of_property_read_string(led, "default-state", &state);
+	if (!ret) {
+		if (!strcmp(state, "on"))
+			hellcreek->led_sync_good.brightness = 1;
+		else if (!strcmp(state, "off"))
+			hellcreek->led_sync_good.brightness = 0;
+		else if (!strcmp(state, "keep"))
+			hellcreek->led_sync_good.brightness =
+				hellcreek_get_brightness(hellcreek,
+							 STATUS_OUT_SYNC_GOOD);
+	}
+
+	hellcreek->led_sync_good.max_brightness = 1;
+	hellcreek->led_sync_good.brightness_set = hellcreek_led_sync_good_set;
+	hellcreek->led_sync_good.brightness_get = hellcreek_led_sync_good_get;
+
+	led = of_get_next_available_child(leds, led);
+	if (!led) {
+		dev_err(hellcreek->dev, "Second LED not specified!\n");
+		ret = -EINVAL;
+		goto out;
+	}
+
+	ret = of_property_read_string(led, "label", &label);
+	hellcreek->led_is_gm.name = ret ? "is_gm" : label;
+
+	ret = of_property_read_string(led, "default-state", &state);
+	if (!ret) {
+		if (!strcmp(state, "on"))
+			hellcreek->led_is_gm.brightness = 1;
+		else if (!strcmp(state, "off"))
+			hellcreek->led_is_gm.brightness = 0;
+		else if (!strcmp(state, "keep"))
+			hellcreek->led_is_gm.brightness =
+				hellcreek_get_brightness(hellcreek,
+							 STATUS_OUT_IS_GM);
+	}
+
+	hellcreek->led_is_gm.max_brightness = 1;
+	hellcreek->led_is_gm.brightness_set = hellcreek_led_is_gm_set;
+	hellcreek->led_is_gm.brightness_get = hellcreek_led_is_gm_get;
+
+	/* Set initial state */
+	if (hellcreek->led_sync_good.brightness == 1)
+		hellcreek_set_brightness(hellcreek, STATUS_OUT_SYNC_GOOD, 1);
+	if (hellcreek->led_is_gm.brightness == 1)
+		hellcreek_set_brightness(hellcreek, STATUS_OUT_IS_GM, 1);
+
+	/* Register both leds */
+	led_classdev_register(hellcreek->dev, &hellcreek->led_sync_good);
+	led_classdev_register(hellcreek->dev, &hellcreek->led_is_gm);
+
+	ret = 0;
+
+out:
+	of_node_put(leds);
+
+	return ret;
+}
+
+int hellcreek_ptp_setup(struct hellcreek *hellcreek)
+{
+	u16 status;
+	int ret;
+
+	/* Set up the overflow work */
+	INIT_DELAYED_WORK(&hellcreek->overflow_work,
+			  hellcreek_ptp_overflow_check);
+
+	/* Setup PTP clock */
+	hellcreek->ptp_clock_info.owner = THIS_MODULE;
+	snprintf(hellcreek->ptp_clock_info.name,
+		 sizeof(hellcreek->ptp_clock_info.name),
+		 dev_name(hellcreek->dev));
+
+	/* IP-Core can add up to 0.5 ns per 8 ns cycle, which means
+	 * accumulator_overflow_rate shall not exceed 62.5 MHz (which adjusts
+	 * the nominal frequency by 6.25%)
+	 */
+	hellcreek->ptp_clock_info.max_adj     = 62500000;
+	hellcreek->ptp_clock_info.n_alarm     = 0;
+	hellcreek->ptp_clock_info.n_pins      = 0;
+	hellcreek->ptp_clock_info.n_ext_ts    = 0;
+	hellcreek->ptp_clock_info.n_per_out   = 0;
+	hellcreek->ptp_clock_info.pps	      = 0;
+	hellcreek->ptp_clock_info.adjfine     = hellcreek_ptp_adjfine;
+	hellcreek->ptp_clock_info.adjtime     = hellcreek_ptp_adjtime;
+	hellcreek->ptp_clock_info.gettime64   = hellcreek_ptp_gettime;
+	hellcreek->ptp_clock_info.settime64   = hellcreek_ptp_settime;
+	hellcreek->ptp_clock_info.enable      = hellcreek_ptp_enable;
+	hellcreek->ptp_clock_info.do_aux_work = hellcreek_hwtstamp_work;
+
+	hellcreek->ptp_clock = ptp_clock_register(&hellcreek->ptp_clock_info,
+						  hellcreek->dev);
+	if (IS_ERR(hellcreek->ptp_clock))
+		return PTR_ERR(hellcreek->ptp_clock);
+
+	/* Enable the offset correction process, if no offset correction is
+	 * already taking place
+	 */
+	status = hellcreek_ptp_read(hellcreek, PR_CLOCK_STATUS_C);
+	if (!(status & PR_CLOCK_STATUS_C_OFS_ACT))
+		hellcreek_ptp_write(hellcreek,
+				    status | PR_CLOCK_STATUS_C_ENA_OFS,
+				    PR_CLOCK_STATUS_C);
+
+	/* Enable the drift correction process */
+	hellcreek_ptp_write(hellcreek, status | PR_CLOCK_STATUS_C_ENA_DRIFT,
+			    PR_CLOCK_STATUS_C);
+
+	/* LED setup */
+	ret = hellcreek_led_setup(hellcreek);
+	if (ret) {
+		if (hellcreek->ptp_clock)
+			ptp_clock_unregister(hellcreek->ptp_clock);
+		return ret;
+	}
+
+	schedule_delayed_work(&hellcreek->overflow_work,
+			      HELLCREEK_OVERFLOW_PERIOD);
+
+	return 0;
+}
+
+void hellcreek_ptp_free(struct hellcreek *hellcreek)
+{
+	led_classdev_unregister(&hellcreek->led_is_gm);
+	led_classdev_unregister(&hellcreek->led_sync_good);
+	cancel_delayed_work_sync(&hellcreek->overflow_work);
+	if (hellcreek->ptp_clock)
+		ptp_clock_unregister(hellcreek->ptp_clock);
+	hellcreek->ptp_clock = NULL;
+}
--- a/drivers/net/dsa/hirschmann/hellcreek_ptp.h
+++ b/drivers/net/dsa/hirschmann/hellcreek_ptp.h
@ -0,0 +1,76 @@
+/* SPDX-License-Identifier: (GPL-2.0 OR MIT) */
+/*
+ * DSA driver for:
+ * Hirschmann Hellcreek TSN switch.
+ *
+ * Copyright (C) 2019,2020 Hochschule Offenburg
+ * Copyright (C) 2019,2020 Linutronix GmbH
+ * Authors: Kurt Kanzenbach <kurt@linutronix.de>
+ *	    Kamil Alkhouri <kamil.alkhouri@hs-offenburg.de>
+ */
+
+#ifndef _HELLCREEK_PTP_H_
+#define _HELLCREEK_PTP_H_
+
+#include <linux/bitops.h>
+#include <linux/ptp_clock_kernel.h>
+
+#include "hellcreek.h"
+
+/* Every jump in time is 7 ns */
+#define MAX_NS_PER_STEP			7L
+
+/* Correct offset at every clock cycle */
+#define MIN_CLK_CYCLES_BETWEEN_STEPS	0
+
+/* Maximum available slow offset resources */
+#define MAX_SLOW_OFFSET_ADJ					\
+	((unsigned long long)((1 << 30) - 1) * MAX_NS_PER_STEP)
+
+/* four times a second overflow check */
+#define HELLCREEK_OVERFLOW_PERIOD	(HZ / 4)
+
+/* PTP Register */
+#define PR_SETTINGS_C			(0x09 * 2)
+#define PR_SETTINGS_C_RES3TS		BIT(4)
+#define PR_SETTINGS_C_TS_SRC_TK_SHIFT	8
+#define PR_SETTINGS_C_TS_SRC_TK_MASK	GENMASK(9, 8)
+#define PR_COMMAND_C			(0x0a * 2)
+#define PR_COMMAND_C_SS			BIT(0)
+
+#define PR_CLOCK_STATUS_C		(0x0c * 2)
+#define PR_CLOCK_STATUS_C_ENA_DRIFT	BIT(12)
+#define PR_CLOCK_STATUS_C_OFS_ACT	BIT(13)
+#define PR_CLOCK_STATUS_C_ENA_OFS	BIT(14)
+
+#define PR_CLOCK_READ_C			(0x0d * 2)
+#define PR_CLOCK_WRITE_C		(0x0e * 2)
+#define PR_CLOCK_OFFSET_C		(0x0f * 2)
+#define PR_CLOCK_DRIFT_C		(0x10 * 2)
+
+#define PR_SS_FREE_DATA_C		(0x12 * 2)
+#define PR_SS_SYNT_DATA_C		(0x14 * 2)
+#define PR_SS_SYNC_DATA_C		(0x16 * 2)
+#define PR_SS_DRAC_DATA_C		(0x18 * 2)
+
+#define STATUS_OUT			(0x60 * 2)
+#define STATUS_OUT_SYNC_GOOD		BIT(0)
+#define STATUS_OUT_IS_GM		BIT(1)
+
+int hellcreek_ptp_setup(struct hellcreek *hellcreek);
+void hellcreek_ptp_free(struct hellcreek *hellcreek);
+u16 hellcreek_ptp_read(struct hellcreek *hellcreek, unsigned int offset);
+void hellcreek_ptp_write(struct hellcreek *hellcreek, u16 data,
+			 unsigned int offset);
+u64 hellcreek_ptp_gettime_seconds(struct hellcreek *hellcreek, u64 ns);
+
+#define ptp_to_hellcreek(ptp)					\
+	container_of(ptp, struct hellcreek, ptp_clock_info)
+
+#define dw_overflow_to_hellcreek(dw)				\
+	container_of(dw, struct hellcreek, overflow_work)
+
+#define led_to_hellcreek(ldev, led)				\
+	container_of(ldev, struct hellcreek, led)
+
+#endif /* _HELLCREEK_PTP_H_ */
--- a/include/linux/platform_data/hirschmann-hellcreek.h
+++ b/include/linux/platform_data/hirschmann-hellcreek.h
@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: (GPL-2.0 or MIT) */
+/*
+ * Hirschmann Hellcreek TSN switch platform data.
+ *
+ * Copyright (C) 2020 Linutronix GmbH
+ * Author Kurt Kanzenbach <kurt@linutronix.de>
+ */
+
+#ifndef _HIRSCHMANN_HELLCREEK_H_
+#define _HIRSCHMANN_HELLCREEK_H_
+
+#include <linux/types.h>
+
+struct hellcreek_platform_data {
+	int num_ports;		/* Amount of switch ports */
+	int is_100_mbits;	/* Is it configured to 100 or 1000 mbit/s */
+	int qbv_support;	/* Qbv support on front TSN ports */
+	int qbv_on_cpu_port;	/* Qbv support on the CPU port */
+	int qbu_support;	/* Qbu support on front TSN ports */
+	u16 module_id;		/* Module identificaton */
+};
+
+#endif /* _HIRSCHMANN_HELLCREEK_H_ */
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@ -45,6 +45,7 @@ struct phylink_link_state;
 #define DSA_TAG_PROTO_OCELOT_VALUE		15
 #define DSA_TAG_PROTO_AR9331_VALUE		16
 #define DSA_TAG_PROTO_RTL4_A_VALUE		17
+#define DSA_TAG_PROTO_HELLCREEK_VALUE		18

 enum dsa_tag_protocol {
 	DSA_TAG_PROTO_NONE		= DSA_TAG_PROTO_NONE_VALUE,
@ -65,6 +66,7 @@ enum dsa_tag_protocol {
 	DSA_TAG_PROTO_OCELOT		= DSA_TAG_PROTO_OCELOT_VALUE,
 	DSA_TAG_PROTO_AR9331		= DSA_TAG_PROTO_AR9331_VALUE,
 	DSA_TAG_PROTO_RTL4_A		= DSA_TAG_PROTO_RTL4_A_VALUE,
+	DSA_TAG_PROTO_HELLCREEK		= DSA_TAG_PROTO_HELLCREEK_VALUE,
 };

 struct packet_type;
@ -534,6 +536,12 @@ struct dsa_switch_ops {
 	void	(*get_regs)(struct dsa_switch *ds, int port,
 			    struct ethtool_regs *regs, void *p);

+	/*
+	 * Upper device tracking.
+	 */
+	int	(*port_prechangeupper)(struct dsa_switch *ds, int port,
+				       struct netdev_notifier_changeupper_info *info);
+
 	/*
 	 * Bridge integration
 	 */
--- a/net/dsa/Kconfig
+++ b/net/dsa/Kconfig
@ -56,6 +56,12 @@ config NET_DSA_TAG_BRCM_PREPEND
 	  Broadcom switches which places the tag before the Ethernet header
 	  (prepended).

+config NET_DSA_TAG_HELLCREEK
+	tristate "Tag driver for Hirschmann Hellcreek TSN switches"
+	help
+	  Say Y or M if you want to enable support for tagging frames
+	  for the Hirschmann Hellcreek TSN switches.
+
 config NET_DSA_TAG_GSWIP
 	tristate "Tag driver for Lantiq / Intel GSWIP switches"
 	help
--- a/net/dsa/Makefile
+++ b/net/dsa/Makefile
@ -10,6 +10,7 @@ obj-$(CONFIG_NET_DSA_TAG_BRCM_COMMON) += tag_brcm.o
 obj-$(CONFIG_NET_DSA_TAG_DSA) += tag_dsa.o
 obj-$(CONFIG_NET_DSA_TAG_EDSA) += tag_edsa.o
 obj-$(CONFIG_NET_DSA_TAG_GSWIP) += tag_gswip.o
+obj-$(CONFIG_NET_DSA_TAG_HELLCREEK) += tag_hellcreek.o
 obj-$(CONFIG_NET_DSA_TAG_KSZ) += tag_ksz.o
 obj-$(CONFIG_NET_DSA_TAG_RTL4_A) += tag_rtl4_a.o
 obj-$(CONFIG_NET_DSA_TAG_LAN9303) += tag_lan9303.o
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@ -2032,10 +2032,22 @@ static int dsa_slave_netdevice_event(struct notifier_block *nb,
 	switch (event) {
 	case NETDEV_PRECHANGEUPPER: {
 		struct netdev_notifier_changeupper_info *info = ptr;
+		struct dsa_switch *ds;
+		struct dsa_port *dp;
+		int err;

 		if (!dsa_slave_dev_check(dev))
 			return dsa_prevent_bridging_8021q_upper(dev, ptr);

+		dp = dsa_slave_to_port(dev);
+		ds = dp->ds;
+
+		if (ds->ops->port_prechangeupper) {
+			err = ds->ops->port_prechangeupper(ds, dp->index, info);
+			if (err)
+				return notifier_from_errno(err);
+		}
+
 		if (is_vlan_dev(info->upper_dev))
 			return dsa_slave_check_8021q_upper(dev, ptr);
 		break;
--- a/net/dsa/tag_hellcreek.c
+++ b/net/dsa/tag_hellcreek.c
@ -0,0 +1,66 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/*
+ * net/dsa/tag_hellcreek.c - Hirschmann Hellcreek switch tag format handling
+ *
+ * Copyright (C) 2019,2020 Linutronix GmbH
+ * Author Kurt Kanzenbach <kurt@linutronix.de>
+ *
+ * Based on tag_ksz.c.
+ */
+
+#include <linux/etherdevice.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <net/dsa.h>
+
+#include "dsa_priv.h"
+
+#define HELLCREEK_TAG_LEN	1
+
+static struct sk_buff *hellcreek_xmit(struct sk_buff *skb,
+				      struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	u8 *tag;
+
+	/* Tag encoding */
+	tag  = skb_put(skb, HELLCREEK_TAG_LEN);
+	*tag = BIT(dp->index);
+
+	return skb;
+}
+
+static struct sk_buff *hellcreek_rcv(struct sk_buff *skb,
+				     struct net_device *dev,
+				     struct packet_type *pt)
+{
+	/* Tag decoding */
+	u8 *tag = skb_tail_pointer(skb) - HELLCREEK_TAG_LEN;
+	unsigned int port = tag[0] & 0x03;
+
+	skb->dev = dsa_master_find_slave(dev, 0, port);
+	if (!skb->dev) {
+		netdev_warn(dev, "Failed to get source port: %d\n", port);
+		return NULL;
+	}
+
+	pskb_trim_rcsum(skb, skb->len - HELLCREEK_TAG_LEN);
+
+	skb->offload_fwd_mark = true;
+
+	return skb;
+}
+
+static const struct dsa_device_ops hellcreek_netdev_ops = {
+	.name	  = "hellcreek",
+	.proto	  = DSA_TAG_PROTO_HELLCREEK,
+	.xmit	  = hellcreek_xmit,
+	.rcv	  = hellcreek_rcv,
+	.overhead = HELLCREEK_TAG_LEN,
+	.tail_tag = true,
+};
+
+MODULE_LICENSE("Dual MIT/GPL");
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_HELLCREEK);
+
+module_dsa_tag_driver(hellcreek_netdev_ops);