net: marvell: prestera: Add driver for Prestera family ASIC devices

Marvell Prestera 98DX326x integrates up to 24 ports of 1GbE with 8
ports of 10GbE uplinks or 2 ports of 40Gbps stacking for a largely
wireless SMB deployment.

The current implementation supports only boards designed for the Marvell
Switchdev solution and requires special firmware.

The core Prestera switching logic is implemented in prestera_main.c,
there is an intermediate hw layer between core logic and firmware. It is
implemented in prestera_hw.c, the purpose of it is to encapsulate hw
related logic, in future there is a plan to support more devices with
different HW related configurations.

This patch contains only basic switch initialization and RX/TX support
over SDMA mechanism.

Currently supported devices have DMA access range <= 32bit and require
ZONE_DMA to be enabled, for such cases SDMA driver checks if the skb
allocated in proper range supported by the Prestera device.

Also meanwhile there is no TX interrupt support in current firmware
version so recycling work is scheduled on each xmit.

Port's mac address is generated from the switch base mac which may be
provided via device-tree (static one or as nvme cell), or randomly
generated. This is required by the firmware.

Co-developed-by: Andrii Savka <andrii.savka@plvision.eu>
Signed-off-by: Andrii Savka <andrii.savka@plvision.eu>
Co-developed-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Co-developed-by: Serhiy Boiko <serhiy.boiko@plvision.eu>
Signed-off-by: Serhiy Boiko <serhiy.boiko@plvision.eu>
Co-developed-by: Serhiy Pshyk <serhiy.pshyk@plvision.eu>
Signed-off-by: Serhiy Pshyk <serhiy.pshyk@plvision.eu>
Co-developed-by: Taras Chornyi <taras.chornyi@plvision.eu>
Signed-off-by: Taras Chornyi <taras.chornyi@plvision.eu>
Co-developed-by: Volodymyr Mytnyk <volodymyr.mytnyk@plvision.eu>
Signed-off-by: Volodymyr Mytnyk <volodymyr.mytnyk@plvision.eu>
Signed-off-by: Vadym Kochan <vadym.kochan@plvision.eu>

drivers/net/ethernet/marvell/Kconfig

@@ -178,5 +178,6 @@ config SKY2_DEBUG
 
 
 source "drivers/net/ethernet/marvell/octeontx2/Kconfig"
+source "drivers/net/ethernet/marvell/prestera/Kconfig"
 
 endif # NET_VENDOR_MARVELL

drivers/net/ethernet/marvell/Makefile

@@ -12,3 +12,4 @@ obj-$(CONFIG_PXA168_ETH) += pxa168_eth.o
 obj-$(CONFIG_SKGE) += skge.o
 obj-$(CONFIG_SKY2) += sky2.o
 obj-y		+= octeontx2/
+obj-y		+= prestera/

drivers/net/ethernet/marvell/prestera/Kconfig

@@ -0,0 +1,13 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Marvell Prestera drivers configuration
+#
+
+config PRESTERA
+	tristate "Marvell Prestera Switch ASICs support"
+	depends on NET_SWITCHDEV && VLAN_8021Q
+	help
+	  This driver supports Marvell Prestera Switch ASICs family.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called prestera.

drivers/net/ethernet/marvell/prestera/Makefile

@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_PRESTERA)	+= prestera.o
+prestera-objs		:= prestera_main.o prestera_hw.o prestera_dsa.o \
+			   prestera_rxtx.o

drivers/net/ethernet/marvell/prestera/prestera.h

@@ -0,0 +1,168 @@
+/* SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0 */
+/* Copyright (c) 2019-2020 Marvell International Ltd. All rights reserved. */
+
+#ifndef _PRESTERA_H_
+#define _PRESTERA_H_
+
+#include <linux/notifier.h>
+#include <linux/skbuff.h>
+#include <linux/workqueue.h>
+#include <uapi/linux/if_ether.h>
+
+struct prestera_fw_rev {
+	u16 maj;
+	u16 min;
+	u16 sub;
+};
+
+struct prestera_port_stats {
+	u64 good_octets_received;
+	u64 bad_octets_received;
+	u64 mac_trans_error;
+	u64 broadcast_frames_received;
+	u64 multicast_frames_received;
+	u64 frames_64_octets;
+	u64 frames_65_to_127_octets;
+	u64 frames_128_to_255_octets;
+	u64 frames_256_to_511_octets;
+	u64 frames_512_to_1023_octets;
+	u64 frames_1024_to_max_octets;
+	u64 excessive_collision;
+	u64 multicast_frames_sent;
+	u64 broadcast_frames_sent;
+	u64 fc_sent;
+	u64 fc_received;
+	u64 buffer_overrun;
+	u64 undersize;
+	u64 fragments;
+	u64 oversize;
+	u64 jabber;
+	u64 rx_error_frame_received;
+	u64 bad_crc;
+	u64 collisions;
+	u64 late_collision;
+	u64 unicast_frames_received;
+	u64 unicast_frames_sent;
+	u64 sent_multiple;
+	u64 sent_deferred;
+	u64 good_octets_sent;
+};
+
+struct prestera_port_caps {
+	u64 supp_link_modes;
+	u8 supp_fec;
+	u8 type;
+	u8 transceiver;
+};
+
+struct prestera_port {
+	struct net_device *dev;
+	struct prestera_switch *sw;
+	u32 id;
+	u32 hw_id;
+	u32 dev_id;
+	u16 fp_id;
+	bool autoneg;
+	u64 adver_link_modes;
+	u8 adver_fec;
+	struct prestera_port_caps caps;
+	struct list_head list;
+	struct {
+		struct prestera_port_stats stats;
+		struct delayed_work caching_dw;
+	} cached_hw_stats;
+};
+
+struct prestera_device {
+	struct device *dev;
+	u8 __iomem *ctl_regs;
+	u8 __iomem *pp_regs;
+	struct prestera_fw_rev fw_rev;
+	void *priv;
+
+	/* called by device driver to handle received packets */
+	void (*recv_pkt)(struct prestera_device *dev);
+
+	/* called by device driver to pass event up to the higher layer */
+	int (*recv_msg)(struct prestera_device *dev, void *msg, size_t size);
+
+	/* called by higher layer to send request to the firmware */
+	int (*send_req)(struct prestera_device *dev, void *in_msg,
+			size_t in_size, void *out_msg, size_t out_size,
+			unsigned int wait);
+};
+
+enum prestera_event_type {
+	PRESTERA_EVENT_TYPE_UNSPEC,
+
+	PRESTERA_EVENT_TYPE_PORT,
+	PRESTERA_EVENT_TYPE_RXTX,
+
+	PRESTERA_EVENT_TYPE_MAX
+};
+
+enum prestera_rxtx_event_id {
+	PRESTERA_RXTX_EVENT_UNSPEC,
+	PRESTERA_RXTX_EVENT_RCV_PKT,
+};
+
+enum prestera_port_event_id {
+	PRESTERA_PORT_EVENT_UNSPEC,
+	PRESTERA_PORT_EVENT_STATE_CHANGED,
+};
+
+struct prestera_port_event {
+	u32 port_id;
+	union {
+		u32 oper_state;
+	} data;
+};
+
+struct prestera_event {
+	u16 id;
+	union {
+		struct prestera_port_event port_evt;
+	};
+};
+
+struct prestera_rxtx;
+
+struct prestera_switch {
+	struct prestera_device *dev;
+	struct prestera_rxtx *rxtx;
+	struct list_head event_handlers;
+	char base_mac[ETH_ALEN];
+	struct list_head port_list;
+	rwlock_t port_list_lock;
+	u32 port_count;
+	u32 mtu_min;
+	u32 mtu_max;
+	u8 id;
+};
+
+struct prestera_rxtx_params {
+	bool use_sdma;
+	u32 map_addr;
+};
+
+#define prestera_dev(sw)		((sw)->dev->dev)
+
+static inline void prestera_write(const struct prestera_switch *sw,
+				  unsigned int reg, u32 val)
+{
+	writel(val, sw->dev->pp_regs + reg);
+}
+
+static inline u32 prestera_read(const struct prestera_switch *sw,
+				unsigned int reg)
+{
+	return readl(sw->dev->pp_regs + reg);
+}
+
+int prestera_device_register(struct prestera_device *dev);
+void prestera_device_unregister(struct prestera_device *dev);
+
+struct prestera_port *prestera_port_find_by_hwid(struct prestera_switch *sw,
+						 u32 dev_id, u32 hw_id);
+
+#endif /* _PRESTERA_H_ */

drivers/net/ethernet/marvell/prestera/prestera_dsa.c

@@ -0,0 +1,104 @@
+// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
+/* Copyright (c) 2020 Marvell International Ltd. All rights reserved */
+
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+
+#include "prestera_dsa.h"
+
+#define PRESTERA_DSA_W0_CMD		GENMASK(31, 30)
+#define PRESTERA_DSA_W0_IS_TAGGED	BIT(29)
+#define PRESTERA_DSA_W0_DEV_NUM		GENMASK(28, 24)
+#define PRESTERA_DSA_W0_PORT_NUM	GENMASK(23, 19)
+#define PRESTERA_DSA_W0_VPT		GENMASK(15, 13)
+#define PRESTERA_DSA_W0_EXT_BIT		BIT(12)
+#define PRESTERA_DSA_W0_VID		GENMASK(11, 0)
+
+#define PRESTERA_DSA_W1_EXT_BIT		BIT(31)
+#define PRESTERA_DSA_W1_CFI_BIT		BIT(30)
+#define PRESTERA_DSA_W1_PORT_NUM	GENMASK(11, 10)
+
+#define PRESTERA_DSA_W2_EXT_BIT		BIT(31)
+#define PRESTERA_DSA_W2_PORT_NUM	BIT(20)
+
+#define PRESTERA_DSA_W3_VID		GENMASK(30, 27)
+#define PRESTERA_DSA_W3_DST_EPORT	GENMASK(23, 7)
+#define PRESTERA_DSA_W3_DEV_NUM		GENMASK(6, 0)
+
+#define PRESTERA_DSA_VID		GENMASK(15, 12)
+#define PRESTERA_DSA_DEV_NUM		GENMASK(11, 5)
+
+int prestera_dsa_parse(struct prestera_dsa *dsa, const u8 *dsa_buf)
+{
+	__be32 *dsa_words = (__be32 *)dsa_buf;
+	enum prestera_dsa_cmd cmd;
+	u32 words[4];
+	u32 field;
+
+	words[0] = ntohl(dsa_words[0]);
+	words[1] = ntohl(dsa_words[1]);
+	words[2] = ntohl(dsa_words[2]);
+	words[3] = ntohl(dsa_words[3]);
+
+	/* set the common parameters */
+	cmd = (enum prestera_dsa_cmd)FIELD_GET(PRESTERA_DSA_W0_CMD, words[0]);
+
+	/* only to CPU is supported */
+	if (unlikely(cmd != PRESTERA_DSA_CMD_TO_CPU))
+		return -EINVAL;
+
+	if (FIELD_GET(PRESTERA_DSA_W0_EXT_BIT, words[0]) == 0)
+		return -EINVAL;
+	if (FIELD_GET(PRESTERA_DSA_W1_EXT_BIT, words[1]) == 0)
+		return -EINVAL;
+	if (FIELD_GET(PRESTERA_DSA_W2_EXT_BIT, words[2]) == 0)
+		return -EINVAL;
+
+	field = FIELD_GET(PRESTERA_DSA_W3_VID, words[3]);
+
+	dsa->vlan.is_tagged = FIELD_GET(PRESTERA_DSA_W0_IS_TAGGED, words[0]);
+	dsa->vlan.cfi_bit = FIELD_GET(PRESTERA_DSA_W1_CFI_BIT, words[1]);
+	dsa->vlan.vpt = FIELD_GET(PRESTERA_DSA_W0_VPT, words[0]);
+	dsa->vlan.vid = FIELD_GET(PRESTERA_DSA_W0_VID, words[0]);
+	dsa->vlan.vid &= ~PRESTERA_DSA_VID;
+	dsa->vlan.vid |= FIELD_PREP(PRESTERA_DSA_VID, field);
+
+	field = FIELD_GET(PRESTERA_DSA_W3_DEV_NUM, words[3]);
+
+	dsa->hw_dev_num = FIELD_GET(PRESTERA_DSA_W0_DEV_NUM, words[0]);
+	dsa->hw_dev_num |= FIELD_PREP(PRESTERA_DSA_DEV_NUM, field);
+
+	dsa->port_num = (FIELD_GET(PRESTERA_DSA_W0_PORT_NUM, words[0]) << 0) |
+			(FIELD_GET(PRESTERA_DSA_W1_PORT_NUM, words[1]) << 5) |
+			(FIELD_GET(PRESTERA_DSA_W2_PORT_NUM, words[2]) << 7);
+
+	return 0;
+}
+
+int prestera_dsa_build(const struct prestera_dsa *dsa, u8 *dsa_buf)
+{
+	__be32 *dsa_words = (__be32 *)dsa_buf;
+	u32 dev_num = dsa->hw_dev_num;
+	u32 words[4] = { 0 };
+
+	words[0] |= FIELD_PREP(PRESTERA_DSA_W0_CMD, PRESTERA_DSA_CMD_FROM_CPU);
+
+	words[0] |= FIELD_PREP(PRESTERA_DSA_W0_DEV_NUM, dev_num);
+	dev_num = FIELD_GET(PRESTERA_DSA_DEV_NUM, dev_num);
+	words[3] |= FIELD_PREP(PRESTERA_DSA_W3_DEV_NUM, dev_num);
+
+	words[3] |= FIELD_PREP(PRESTERA_DSA_W3_DST_EPORT, dsa->port_num);
+
+	words[0] |= FIELD_PREP(PRESTERA_DSA_W0_EXT_BIT, 1);
+	words[1] |= FIELD_PREP(PRESTERA_DSA_W1_EXT_BIT, 1);
+	words[2] |= FIELD_PREP(PRESTERA_DSA_W2_EXT_BIT, 1);
+
+	dsa_words[0] = htonl(words[0]);
+	dsa_words[1] = htonl(words[1]);
+	dsa_words[2] = htonl(words[2]);
+	dsa_words[3] = htonl(words[3]);
+
+	return 0;
+}

drivers/net/ethernet/marvell/prestera/prestera_dsa.h

@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0 */
+/* Copyright (c) 2020 Marvell International Ltd. All rights reserved. */
+
+#ifndef __PRESTERA_DSA_H_
+#define __PRESTERA_DSA_H_
+
+#include <linux/types.h>
+
+#define PRESTERA_DSA_HLEN	16
+
+enum prestera_dsa_cmd {
+	/* DSA command is "To CPU" */
+	PRESTERA_DSA_CMD_TO_CPU = 0,
+
+	/* DSA command is "From CPU" */
+	PRESTERA_DSA_CMD_FROM_CPU,
+};
+
+struct prestera_dsa_vlan {
+	u16 vid;
+	u8 vpt;
+	u8 cfi_bit;
+	bool is_tagged;
+};
+
+struct prestera_dsa {
+	struct prestera_dsa_vlan vlan;
+	u32 hw_dev_num;
+	u32 port_num;
+};
+
+int prestera_dsa_parse(struct prestera_dsa *dsa, const u8 *dsa_buf);
+int prestera_dsa_build(const struct prestera_dsa *dsa, u8 *dsa_buf);
+
+#endif /* _PRESTERA_DSA_H_ */