[PATCH net-next v1 0/3] net: dsa: Add RMU support

[PATCH net-next v1 0/3] net: dsa: Add RMU support

[Mattias Forsblad]

The Marvell SOHO switches have the ability to receive and transmit
Remote Management Frames (Frame2Reg) to the CPU through the
attached network interface.
This is handled by the Remote Management Unit (RMU).
These frames can contain different payloads:
single switch register read and writes, daisy chained switch
register read and writes, RMON/MIB dump/dump clear and ATU dump.
The dump functions are very costly over MDIO but it's
only a couple of network packets via the RMU.

Next step could be to implement ATU dump.
We've found that the gain to use RMU for single
register read and writes is neglible.

RFC -> v1:
  - Track master interface availability.
  - Validate destination MAC for incoming frames.
  - Rate limit outputs.
  - Cleanup setup function validating upstream port on switch.
  - Fix return values when setting up RMU.
  - Prefix defines correctly.
  - Fix aligned accesses.
  - Validate that switch exists for incoming frames.
  - Split RMON stats function.

Regards,
Mattias Forsblad

Mattias Forsblad (3):
  dsa: Implement RMU layer in DSA
  dsa: mv88e6xxx: Add support for RMU in select switches
  rmon: Use RMU if available

 drivers/net/dsa/mv88e6xxx/Makefile  |   1 +
 drivers/net/dsa/mv88e6xxx/chip.c    |  54 +++++-
 drivers/net/dsa/mv88e6xxx/chip.h    |  20 ++
 drivers/net/dsa/mv88e6xxx/global1.c |  84 +++++++++
 drivers/net/dsa/mv88e6xxx/global1.h |   3 +
 drivers/net/dsa/mv88e6xxx/rmu.c     | 276 ++++++++++++++++++++++++++++
 drivers/net/dsa/mv88e6xxx/rmu.h     |  33 ++++
 include/net/dsa.h                   |   7 +
 include/uapi/linux/if_ether.h       |   1 +
 net/dsa/tag_dsa.c                   | 109 ++++++++++-
 10 files changed, 578 insertions(+), 10 deletions(-)
 create mode 100644 drivers/net/dsa/mv88e6xxx/rmu.c
 create mode 100644 drivers/net/dsa/mv88e6xxx/rmu.h

--
2.25.1

[PATCH net-next v1 1/3] dsa: Implement RMU layer in DSA

[Mattias Forsblad]

Support handling of layer 2 part for RMU frames which is
handled in-band with other DSA traffic.

Signed-off-by: Mattias Forsblad <mattias.forsblad@gmail.com>
---
 include/net/dsa.h             |   7 +++
 include/uapi/linux/if_ether.h |   1 +
 net/dsa/tag_dsa.c             | 109 +++++++++++++++++++++++++++++++++-
 3 files changed, 114 insertions(+), 3 deletions(-)

diff --git a/include/net/dsa.h b/include/net/dsa.h
index f2ce12860546..54f7f3494f84 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@@ -92,6 +92,7 @@ struct dsa_switch;
 struct dsa_device_ops {
 	struct sk_buff *(*xmit)(struct sk_buff *skb, struct net_device *dev);
 	struct sk_buff *(*rcv)(struct sk_buff *skb, struct net_device *dev);
+	int (*inband_xmit)(struct sk_buff *skb, struct net_device *dev, int seq_no);
 	void (*flow_dissect)(const struct sk_buff *skb, __be16 *proto,
 			     int *offset);
 	int (*connect)(struct dsa_switch *ds);
@@ -1193,6 +1194,12 @@ struct dsa_switch_ops {
 	void	(*master_state_change)(struct dsa_switch *ds,
 				       const struct net_device *master,
 				       bool operational);
+
+	/*
+	 * RMU operations
+	 */
+	int (*inband_receive)(struct dsa_switch *ds, struct sk_buff *skb,
+			int seq_no);
 };
 
 #define DSA_DEVLINK_PARAM_DRIVER(_id, _name, _type, _cmodes)		\
diff --git a/include/uapi/linux/if_ether.h b/include/uapi/linux/if_ether.h
index d370165bc621..9de1bdc7cccc 100644
--- a/include/uapi/linux/if_ether.h
+++ b/include/uapi/linux/if_ether.h
@@ -158,6 +158,7 @@
 #define ETH_P_MCTP	0x00FA		/* Management component transport
 					 * protocol packets
 					 */
+#define ETH_P_RMU_DSA   0x00FB          /* RMU DSA protocol */
 
 /*
  *	This is an Ethernet frame header.
diff --git a/net/dsa/tag_dsa.c b/net/dsa/tag_dsa.c
index e4b6e3f2a3db..36f02e7dd3c3 100644
--- a/net/dsa/tag_dsa.c
+++ b/net/dsa/tag_dsa.c
@@ -123,6 +123,90 @@ enum dsa_code {
 	DSA_CODE_RESERVED_7    = 7
 };
 
+#define DSA_RMU_RESV1   0x3e
+#define DSA_RMU         1
+#define DSA_RMU_PRIO    6
+#define DSA_RMU_RESV2   0xf
+
+static int dsa_inband_xmit_ll(struct sk_buff *skb, struct net_device *dev,
+			      const u8 *header, int header_len, int seq_no)
+{
+	static const u8 dest_addr[ETH_ALEN] = { 0x01, 0x50, 0x43, 0x00, 0x00, 0x00 };
+	struct dsa_port *dp;
+	struct ethhdr *eth;
+	u8 *data;
+
+	if (!dev)
+		return -ENODEV;
+
+	dp = dsa_slave_to_port(dev);
+	if (!dp)
+		return -ENODEV;
+
+	/* Create RMU L2 header */
+	data = skb_push(skb, 6);
+	data[0] = (DSA_CMD_FROM_CPU << 6) | dp->ds->index;
+	data[1] = DSA_RMU_RESV1 << 2 | DSA_RMU << 1;
+	data[2] = DSA_RMU_PRIO << 5 | DSA_RMU_RESV2;
+	data[3] = seq_no;
+	data[4] = 0;
+	data[5] = 0;
+
+	/* Add header if any */
+	if (header) {
+		data = skb_push(skb, header_len);
+		memcpy(data, header, header_len);
+	}
+
+	/* Create MAC header */
+	eth = (struct ethhdr *)skb_push(skb, 2 * ETH_ALEN);
+	memcpy(eth->h_source, dev->dev_addr, ETH_ALEN);
+	memcpy(eth->h_dest, dest_addr, ETH_ALEN);
+
+	skb->protocol = htons(ETH_P_RMU_DSA);
+
+	dev_queue_xmit(skb);
+
+	return 0;
+}
+
+static int dsa_inband_rcv_ll(struct sk_buff *skb, struct net_device *dev)
+{
+	struct dsa_switch *ds;
+	int source_device;
+	u8 *dsa_header;
+	int rcv_seqno;
+	int ret = 0;
+
+	if (!dev || !dev->dsa_ptr)
+		return 0;
+
+	ds = dev->dsa_ptr->ds;
+	if (!ds)
+		return 0;
+
+	dsa_header = skb->data - 2;
+
+	source_device = dsa_header[0] & 0x1f;
+	ds = dsa_switch_find(ds->dst->index, source_device);
+	if (!ds) {
+		net_dbg_ratelimited("DSA inband: Didn't find switch with index %d", source_device);
+		return -EINVAL;
+	}
+
+	/* Get rcv seqno */
+	rcv_seqno = dsa_header[3];
+
+	skb_pull(skb, DSA_HLEN);
+
+	if (ds->ops && ds->ops->inband_receive(ds, skb, rcv_seqno)) {
+		dev_dbg_ratelimited(ds->dev, "DSA inband: error decoding packet");
+		ret = -EIO;
+	}
+
+	return ret;
+}
+
 static struct sk_buff *dsa_xmit_ll(struct sk_buff *skb, struct net_device *dev,
 				   u8 extra)
 {
@@ -218,9 +302,7 @@ static struct sk_buff *dsa_rcv_ll(struct sk_buff *skb, struct net_device *dev,
 
 		switch (code) {
 		case DSA_CODE_FRAME2REG:
-			/* Remote management is not implemented yet,
-			 * drop.
-			 */
+			dsa_inband_rcv_ll(skb, dev);
 			return NULL;
 		case DSA_CODE_ARP_MIRROR:
 		case DSA_CODE_POLICY_MIRROR:
@@ -325,6 +407,12 @@ static struct sk_buff *dsa_rcv_ll(struct sk_buff *skb, struct net_device *dev,
 
 #if IS_ENABLED(CONFIG_NET_DSA_TAG_DSA)
 
+static int dsa_inband_xmit(struct sk_buff *skb, struct net_device *dev,
+			   int seq_no)
+{
+	return dsa_inband_xmit_ll(skb, dev, NULL, 0, seq_no);
+}
+
 static struct sk_buff *dsa_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	return dsa_xmit_ll(skb, dev, 0);
@@ -343,6 +431,7 @@ static const struct dsa_device_ops dsa_netdev_ops = {
 	.proto	  = DSA_TAG_PROTO_DSA,
 	.xmit	  = dsa_xmit,
 	.rcv	  = dsa_rcv,
+	.inband_xmit = dsa_inband_xmit,
 	.needed_headroom = DSA_HLEN,
 };
 
@@ -354,6 +443,19 @@ MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_DSA);
 
 #define EDSA_HLEN 8
 
+static int edsa_inband_xmit(struct sk_buff *skb, struct net_device *dev,
+			    int seq_no)
+{
+	u8 edsa_header[4];
+
+	edsa_header[0] = (ETH_P_EDSA >> 8) & 0xff;
+	edsa_header[1] = ETH_P_EDSA & 0xff;
+	edsa_header[2] = 0x00;
+	edsa_header[3] = 0x00;
+
+	return dsa_inband_xmit_ll(skb, dev, edsa_header, 4, seq_no);
+}
+
 static struct sk_buff *edsa_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	u8 *edsa_header;
@@ -385,6 +487,7 @@ static const struct dsa_device_ops edsa_netdev_ops = {
 	.proto	  = DSA_TAG_PROTO_EDSA,
 	.xmit	  = edsa_xmit,
 	.rcv	  = edsa_rcv,
+	.inband_xmit = edsa_inband_xmit,
 	.needed_headroom = EDSA_HLEN,
 };
 
-- 
2.25.1

[PATCH net-next v1 2/3] dsa: mv88e6xxx: Add support for RMU in select switches

[Mattias Forsblad]

Implement support for handling RMU layer 3 frames
including receive and transmit.

Signed-off-by: Mattias Forsblad <mattias.forsblad@gmail.com>
---
 drivers/net/dsa/mv88e6xxx/Makefile  |   1 +
 drivers/net/dsa/mv88e6xxx/chip.c    |  13 ++
 drivers/net/dsa/mv88e6xxx/chip.h    |  20 ++
 drivers/net/dsa/mv88e6xxx/global1.c |  84 +++++++++
 drivers/net/dsa/mv88e6xxx/global1.h |   3 +
 drivers/net/dsa/mv88e6xxx/rmu.c     | 276 ++++++++++++++++++++++++++++
 drivers/net/dsa/mv88e6xxx/rmu.h     |  33 ++++
 7 files changed, 430 insertions(+)
 create mode 100644 drivers/net/dsa/mv88e6xxx/rmu.c
 create mode 100644 drivers/net/dsa/mv88e6xxx/rmu.h

diff --git a/drivers/net/dsa/mv88e6xxx/Makefile b/drivers/net/dsa/mv88e6xxx/Makefile
index c8eca2b6f959..105d7bd832c9 100644
--- a/drivers/net/dsa/mv88e6xxx/Makefile
+++ b/drivers/net/dsa/mv88e6xxx/Makefile
@@ -15,3 +15,4 @@ mv88e6xxx-objs += port_hidden.o
 mv88e6xxx-$(CONFIG_NET_DSA_MV88E6XXX_PTP) += ptp.o
 mv88e6xxx-objs += serdes.o
 mv88e6xxx-objs += smi.o
+mv88e6xxx-objs += rmu.o
diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
index 07e9a4da924c..4c0510abd875 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.c
+++ b/drivers/net/dsa/mv88e6xxx/chip.c
@@ -42,6 +42,7 @@
 #include "ptp.h"
 #include "serdes.h"
 #include "smi.h"
+#include "rmu.h"
 
 static void assert_reg_lock(struct mv88e6xxx_chip *chip)
 {
@@ -1529,6 +1530,10 @@ static int mv88e6xxx_trunk_setup(struct mv88e6xxx_chip *chip)
 
 static int mv88e6xxx_rmu_setup(struct mv88e6xxx_chip *chip)
 {
+	if (chip->info->ops->rmu_enable)
+		if (!chip->info->ops->rmu_enable(chip))
+			return mv88e6xxx_rmu_init(chip);
+
 	if (chip->info->ops->rmu_disable)
 		return chip->info->ops->rmu_disable(chip);
 
@@ -4090,6 +4095,7 @@ static const struct mv88e6xxx_ops mv88e6085_ops = {
 	.ppu_disable = mv88e6185_g1_ppu_disable,
 	.reset = mv88e6185_g1_reset,
 	.rmu_disable = mv88e6085_g1_rmu_disable,
+	.rmu_enable = mv88e6085_g1_rmu_enable,
 	.vtu_getnext = mv88e6352_g1_vtu_getnext,
 	.vtu_loadpurge = mv88e6352_g1_vtu_loadpurge,
 	.stu_getnext = mv88e6352_g1_stu_getnext,
@@ -4173,6 +4179,7 @@ static const struct mv88e6xxx_ops mv88e6097_ops = {
 	.pot_clear = mv88e6xxx_g2_pot_clear,
 	.reset = mv88e6352_g1_reset,
 	.rmu_disable = mv88e6085_g1_rmu_disable,
+	.rmu_enable = mv88e6085_g1_rmu_enable,
 	.vtu_getnext = mv88e6352_g1_vtu_getnext,
 	.vtu_loadpurge = mv88e6352_g1_vtu_loadpurge,
 	.phylink_get_caps = mv88e6095_phylink_get_caps,
@@ -5292,6 +5299,7 @@ static const struct mv88e6xxx_ops mv88e6352_ops = {
 	.pot_clear = mv88e6xxx_g2_pot_clear,
 	.reset = mv88e6352_g1_reset,
 	.rmu_disable = mv88e6352_g1_rmu_disable,
+	.rmu_enable = mv88e6352_g1_rmu_enable,
 	.atu_get_hash = mv88e6165_g1_atu_get_hash,
 	.atu_set_hash = mv88e6165_g1_atu_set_hash,
 	.vtu_getnext = mv88e6352_g1_vtu_getnext,
@@ -5359,6 +5367,7 @@ static const struct mv88e6xxx_ops mv88e6390_ops = {
 	.pot_clear = mv88e6xxx_g2_pot_clear,
 	.reset = mv88e6352_g1_reset,
 	.rmu_disable = mv88e6390_g1_rmu_disable,
+	.rmu_enable = mv88e6390_g1_rmu_enable,
 	.atu_get_hash = mv88e6165_g1_atu_get_hash,
 	.atu_set_hash = mv88e6165_g1_atu_set_hash,
 	.vtu_getnext = mv88e6390_g1_vtu_getnext,
@@ -5426,6 +5435,7 @@ static const struct mv88e6xxx_ops mv88e6390x_ops = {
 	.pot_clear = mv88e6xxx_g2_pot_clear,
 	.reset = mv88e6352_g1_reset,
 	.rmu_disable = mv88e6390_g1_rmu_disable,
+	.rmu_enable = mv88e6390_g1_rmu_enable,
 	.atu_get_hash = mv88e6165_g1_atu_get_hash,
 	.atu_set_hash = mv88e6165_g1_atu_set_hash,
 	.vtu_getnext = mv88e6390_g1_vtu_getnext,
@@ -5496,6 +5506,7 @@ static const struct mv88e6xxx_ops mv88e6393x_ops = {
 	.pot_clear = mv88e6xxx_g2_pot_clear,
 	.reset = mv88e6352_g1_reset,
 	.rmu_disable = mv88e6390_g1_rmu_disable,
+	.rmu_enable = mv88e6390_g1_rmu_enable,
 	.atu_get_hash = mv88e6165_g1_atu_get_hash,
 	.atu_set_hash = mv88e6165_g1_atu_set_hash,
 	.vtu_getnext = mv88e6390_g1_vtu_getnext,
@@ -6918,6 +6929,8 @@ static const struct dsa_switch_ops mv88e6xxx_switch_ops = {
 	.crosschip_lag_change	= mv88e6xxx_crosschip_lag_change,
 	.crosschip_lag_join	= mv88e6xxx_crosschip_lag_join,
 	.crosschip_lag_leave	= mv88e6xxx_crosschip_lag_leave,
+	.inband_receive         = mv88e6xxx_inband_rcv,
+	.master_state_change	= mv88e6xxx_rmu_master_change,
 };
 
 static int mv88e6xxx_register_switch(struct mv88e6xxx_chip *chip)
diff --git a/drivers/net/dsa/mv88e6xxx/chip.h b/drivers/net/dsa/mv88e6xxx/chip.h
index e693154cf803..024f45cc1476 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.h
+++ b/drivers/net/dsa/mv88e6xxx/chip.h
@@ -33,6 +33,8 @@
 
 #define MV88E6XXX_MAX_GPIO	16
 
+#define MV88E6XXX_WAIT_POLL_TIME_MS		200
+
 enum mv88e6xxx_egress_mode {
 	MV88E6XXX_EGRESS_MODE_UNMODIFIED,
 	MV88E6XXX_EGRESS_MODE_UNTAGGED,
@@ -266,6 +268,7 @@ struct mv88e6xxx_vlan {
 struct mv88e6xxx_port {
 	struct mv88e6xxx_chip *chip;
 	int port;
+	u64 rmu_raw_stats[64];
 	struct mv88e6xxx_vlan bridge_pvid;
 	u64 serdes_stats[2];
 	u64 atu_member_violation;
@@ -282,6 +285,18 @@ struct mv88e6xxx_port {
 	struct devlink_region *region;
 };
 
+struct mv88e6xxx_rmu {
+	/* RMU resources */
+	struct net_device *netdev;
+	struct mv88e6xxx_bus_ops *ops;
+	struct completion completion;
+	/* Mutex for RMU operations */
+	struct mutex mutex;
+	u16 got_id;
+	u8 request_cmd;
+	u8 seq_no;
+};
+
 enum mv88e6xxx_region_id {
 	MV88E6XXX_REGION_GLOBAL1 = 0,
 	MV88E6XXX_REGION_GLOBAL2,
@@ -410,12 +425,16 @@ struct mv88e6xxx_chip {
 
 	/* Bridge MST to SID mappings */
 	struct list_head msts;
+
+	/* RMU resources */
+	struct mv88e6xxx_rmu rmu;
 };
 
 struct mv88e6xxx_bus_ops {
 	int (*read)(struct mv88e6xxx_chip *chip, int addr, int reg, u16 *val);
 	int (*write)(struct mv88e6xxx_chip *chip, int addr, int reg, u16 val);
 	int (*init)(struct mv88e6xxx_chip *chip);
+	int (*get_rmon)(struct mv88e6xxx_chip *chip, int port, uint64_t *data);
 };
 
 struct mv88e6xxx_mdio_bus {
@@ -637,6 +656,7 @@ struct mv88e6xxx_ops {
 
 	/* Remote Management Unit operations */
 	int (*rmu_disable)(struct mv88e6xxx_chip *chip);
+	int (*rmu_enable)(struct mv88e6xxx_chip *chip);
 
 	/* Precision Time Protocol operations */
 	const struct mv88e6xxx_ptp_ops *ptp_ops;
diff --git a/drivers/net/dsa/mv88e6xxx/global1.c b/drivers/net/dsa/mv88e6xxx/global1.c
index 5848112036b0..5d86dbf39347 100644
--- a/drivers/net/dsa/mv88e6xxx/global1.c
+++ b/drivers/net/dsa/mv88e6xxx/global1.c
@@ -466,18 +466,102 @@ int mv88e6085_g1_rmu_disable(struct mv88e6xxx_chip *chip)
 				      MV88E6085_G1_CTL2_RM_ENABLE, 0);
 }
 
+int mv88e6085_g1_rmu_enable(struct mv88e6xxx_chip *chip)
+{
+	int val = MV88E6352_G1_CTL2_RMU_MODE_DISABLED;
+	int upstream_port = -1;
+
+	upstream_port = dsa_switch_upstream_port(chip->ds);
+	dev_dbg(chip->dev, "RMU: Enabling on port %d", upstream_port);
+	if (upstream_port < 0)
+		return -EOPNOTSUPP;
+
+	switch (upstream_port) {
+	case 9:
+		val = MV88E6085_G1_CTL2_RM_ENABLE;
+		break;
+	case 10:
+		val = MV88E6085_G1_CTL2_RM_ENABLE | MV88E6085_G1_CTL2_P10RM;
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return mv88e6xxx_g1_ctl2_mask(chip, MV88E6085_G1_CTL2_P10RM |
+				      MV88E6085_G1_CTL2_RM_ENABLE, val);
+}
+
 int mv88e6352_g1_rmu_disable(struct mv88e6xxx_chip *chip)
 {
 	return mv88e6xxx_g1_ctl2_mask(chip, MV88E6352_G1_CTL2_RMU_MODE_MASK,
 				      MV88E6352_G1_CTL2_RMU_MODE_DISABLED);
 }
 
+int mv88e6352_g1_rmu_enable(struct mv88e6xxx_chip *chip)
+{
+	int val = MV88E6352_G1_CTL2_RMU_MODE_DISABLED;
+	int upstream_port;
+
+	upstream_port = dsa_switch_upstream_port(chip->ds);
+	dev_dbg(chip->dev, "RMU: Enabling on port %d", upstream_port);
+	if (upstream_port < 0)
+		return -EOPNOTSUPP;
+
+	switch (upstream_port) {
+	case 4:
+		val = MV88E6352_G1_CTL2_RMU_MODE_PORT_4;
+		break;
+	case 5:
+		val = MV88E6352_G1_CTL2_RMU_MODE_PORT_5;
+		break;
+	case 6:
+		val = MV88E6352_G1_CTL2_RMU_MODE_PORT_6;
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return mv88e6xxx_g1_ctl2_mask(chip, MV88E6352_G1_CTL2_RMU_MODE_MASK,
+			val);
+}
+
 int mv88e6390_g1_rmu_disable(struct mv88e6xxx_chip *chip)
 {
 	return mv88e6xxx_g1_ctl2_mask(chip, MV88E6390_G1_CTL2_RMU_MODE_MASK,
 				      MV88E6390_G1_CTL2_RMU_MODE_DISABLED);
 }
 
+int mv88e6390_g1_rmu_enable(struct mv88e6xxx_chip *chip)
+{
+	int val = MV88E6390_G1_CTL2_RMU_MODE_DISABLED;
+	int upstream_port;
+
+	upstream_port = dsa_switch_upstream_port(chip->ds);
+	dev_dbg(chip->dev, "RMU: Enabling on port %d", upstream_port);
+	if (upstream_port < 0)
+		return -EOPNOTSUPP;
+
+	switch (upstream_port) {
+	case 0:
+		val = MV88E6390_G1_CTL2_RMU_MODE_PORT_0;
+		break;
+	case 1:
+		val = MV88E6390_G1_CTL2_RMU_MODE_PORT_1;
+		break;
+	case 9:
+		val = MV88E6390_G1_CTL2_RMU_MODE_PORT_9;
+		break;
+	case 10:
+		val = MV88E6390_G1_CTL2_RMU_MODE_PORT_10;
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return mv88e6xxx_g1_ctl2_mask(chip, MV88E6390_G1_CTL2_RMU_MODE_MASK,
+			val);
+}
+
 int mv88e6390_g1_stats_set_histogram(struct mv88e6xxx_chip *chip)
 {
 	return mv88e6xxx_g1_ctl2_mask(chip, MV88E6390_G1_CTL2_HIST_MODE_MASK,
diff --git a/drivers/net/dsa/mv88e6xxx/global1.h b/drivers/net/dsa/mv88e6xxx/global1.h
index 65958b2a0d3a..7e786503734a 100644
--- a/drivers/net/dsa/mv88e6xxx/global1.h
+++ b/drivers/net/dsa/mv88e6xxx/global1.h
@@ -313,8 +313,11 @@ int mv88e6250_g1_ieee_pri_map(struct mv88e6xxx_chip *chip);
 int mv88e6185_g1_set_cascade_port(struct mv88e6xxx_chip *chip, int port);
 
 int mv88e6085_g1_rmu_disable(struct mv88e6xxx_chip *chip);
+int mv88e6085_g1_rmu_enable(struct mv88e6xxx_chip *chip);
 int mv88e6352_g1_rmu_disable(struct mv88e6xxx_chip *chip);
+int mv88e6352_g1_rmu_enable(struct mv88e6xxx_chip *chip);
 int mv88e6390_g1_rmu_disable(struct mv88e6xxx_chip *chip);
+int mv88e6390_g1_rmu_enable(struct mv88e6xxx_chip *chip);
 
 int mv88e6xxx_g1_set_device_number(struct mv88e6xxx_chip *chip, int index);
 
diff --git a/drivers/net/dsa/mv88e6xxx/rmu.c b/drivers/net/dsa/mv88e6xxx/rmu.c
new file mode 100644
index 000000000000..1d8ced7d691e
--- /dev/null
+++ b/drivers/net/dsa/mv88e6xxx/rmu.c
@@ -0,0 +1,276 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Marvell 88E6xxx Switch Remote Management Unit Support
+ *
+ * Copyright (c) 2022 Mattias Forsblad <mattias.forsblad@gmail.com>
+ *
+ */
+
+#include <asm/unaligned.h>
+#include "rmu.h"
+#include "global1.h"
+
+static int mv88e6xxx_validate_port_mac(struct dsa_switch *ds, struct sk_buff *skb)
+{
+	unsigned char *ethhdr;
+	struct dsa_port *dp;
+	u8 pkt_port;
+
+	pkt_port = (skb->data[7] >> 3) & 0xf;
+	dp = dsa_to_port(ds, pkt_port);
+	if (!dp) {
+		dev_dbg_ratelimited(ds->dev, "RMU: couldn't find port for %d\n", pkt_port);
+		return -ENXIO;
+	}
+
+	/* Check matching MAC */
+	ethhdr = skb_mac_header(skb);
+	if (memcmp(dp->slave->dev_addr, ethhdr, ETH_ALEN)) {
+		dev_dbg_ratelimited(ds->dev, "RMU: mismatching MAC address for request. Rx %pM expecting %pM\n",
+				    ethhdr, dp->slave->dev_addr);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+int mv88e6xxx_inband_rcv(struct dsa_switch *ds, struct sk_buff *skb, int seq_no)
+{
+	struct mv88e6xxx_chip *chip = ds->priv;
+	struct mv88e6xxx_port *port;
+	u16 prodnum;
+	u16 format;
+	u16 code;
+	u8 pkt_dev;
+	u8 pkt_prt;
+	int i;
+
+	/* Extract response data */
+	format = get_unaligned_be16(&skb->data[0]);
+	if (format != htons(MV88E6XXX_RMU_RESP_FORMAT_1) &&
+	    format != htons(MV88E6XXX_RMU_RESP_FORMAT_2)) {
+		dev_err_ratelimited(chip->dev, "RMU: received unknown format 0x%04x", format);
+		goto out;
+	}
+
+	code = get_unaligned_be16(&skb->data[4]);
+	if (code == ntohs(MV88E6XXX_RMU_RESP_ERROR)) {
+		dev_err_ratelimited(chip->dev, "RMU: error response code 0x%04x", code);
+		goto out;
+	}
+
+	pkt_dev = skb->data[6] & 0x1f;
+	if (!dsa_switch_find(ds->dst->index, pkt_dev)) {
+		dev_err_ratelimited(chip->dev, "RMU: response from unknown chip with index %d\n",
+				    pkt_dev);
+		goto out;
+	}
+
+	/* Check sequence number */
+	if (seq_no != chip->rmu.seq_no) {
+		dev_err_ratelimited(chip->dev, "RMU: wrong seqno received %d, expected %d",
+				    seq_no, chip->rmu.seq_no);
+		goto out;
+	}
+
+	/* Check response code */
+	switch (chip->rmu.request_cmd) {
+	case MV88E6XXX_RMU_REQ_GET_ID: {
+		if (code == MV88E6XXX_RMU_RESP_CODE_GOT_ID) {
+			prodnum = get_unaligned_be16(&skb->data[2]);
+			chip->rmu.got_id = prodnum;
+			dev_info_ratelimited(chip->dev, "RMU: received id OK with product number: 0x%04x\n",
+					     chip->rmu.got_id);
+		} else {
+			dev_dbg_ratelimited(chip->dev,
+					    "RMU: unknown response for GET_ID format 0x%04x code 0x%04x",
+					    format, code);
+		}
+		break;
+	}
+	case MV88E6XXX_RMU_REQ_DUMP_MIB:
+		if (code == MV88E6XXX_RMU_RESP_CODE_DUMP_MIB &&
+		    !mv88e6xxx_validate_port_mac(ds, skb)) {
+			pkt_prt = (skb->data[7] & 0x78) >> 3;
+			port = &chip->ports[pkt_prt];
+			if (!port) {
+				dev_err_ratelimited(chip->dev, "RMU: illegal port number in response: %d\n",
+						    pkt_prt);
+				goto out;
+			}
+
+			/* Copy whole array for further
+			 * processing according to chip type
+			 */
+			for (i = 0; i < MV88E6XXX_RMU_MAX_RMON; i++)
+				port->rmu_raw_stats[i] = get_unaligned_be32(&skb->data[12 + i * 4]);
+		}
+		break;
+	default:
+		dev_err_ratelimited(chip->dev,
+				    "RMU: unknown response format 0x%04x and code 0x%04x from chip %d\n",
+				    format, code, chip->ds->index);
+		break;
+	}
+
+out:
+	complete(&chip->rmu.completion);
+
+	return 0;
+}
+
+static int mv88e6xxx_rmu_tx(struct mv88e6xxx_chip *chip, int port,
+			    const char *msg, int len)
+{
+	const struct dsa_device_ops *tag_ops;
+	const struct dsa_port *dp;
+	unsigned char *ethhdr;
+	unsigned char *data;
+	struct sk_buff *skb;
+
+	dp = dsa_to_port(chip->ds, port);
+	if (!dp || !dp->cpu_dp)
+		return 0;
+
+	tag_ops = dp->cpu_dp->tag_ops;
+	if (!tag_ops)
+		return -ENODEV;
+
+	skb = netdev_alloc_skb(chip->rmu.netdev, 64);
+	if (!skb)
+		return -ENOMEM;
+
+	skb_reserve(skb, 2 * ETH_HLEN + tag_ops->needed_headroom);
+	skb_reset_network_header(skb);
+	skb->pkt_type = PACKET_OUTGOING;
+	skb->dev = chip->rmu.netdev;
+
+	/* Create RMU L3 message */
+	data = skb_put(skb, len);
+	memcpy(data, msg, len);
+
+	ethhdr = skb_mac_header(skb);
+
+	return tag_ops->inband_xmit(skb, dp->slave, ++chip->rmu.seq_no);
+}
+
+static int mv88e6xxx_rmu_send_wait(struct mv88e6xxx_chip *chip, int port,
+				   int request, const char *msg, int len)
+{
+	const struct dsa_port *dp;
+	int ret = 0;
+
+	dp = dsa_to_port(chip->ds, port);
+	if (!dp)
+		return 0;
+
+	mutex_lock(&chip->rmu.mutex);
+
+	chip->rmu.request_cmd = request;
+
+	ret = mv88e6xxx_rmu_tx(chip, port, msg, len);
+	if (ret == -ENODEV) {
+		/* Device not ready yet? Try again later */
+		ret = 0;
+		goto out;
+	}
+
+	if (ret) {
+		dev_dbg(chip->dev, "RMU: error transmitting request (%d)", ret);
+		goto out;
+	}
+
+	ret = wait_for_completion_timeout(&chip->rmu.completion,
+					  msecs_to_jiffies(MV88E6XXX_WAIT_POLL_TIME_MS));
+	if (ret == 0) {
+		dev_dbg(chip->dev,
+			"RMU: timeout waiting for request %d (%d) on dev:port %d:%d\n",
+			request, ret, chip->ds->index, port);
+		ret = -ETIMEDOUT;
+	}
+
+out:
+	mutex_unlock(&chip->rmu.mutex);
+
+	return ret > 0 ? 0 : ret;
+}
+
+static int mv88e6xxx_rmu_get_id(struct mv88e6xxx_chip *chip, int port)
+{
+	const u8 get_id[8] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
+	int ret = -1;
+
+	if (chip->rmu.got_id)
+		return 0;
+
+	chip->rmu.netdev = dev_get_by_name(&init_net, "chan0");
+	if (!chip->rmu.netdev) {
+		dev_dbg(chip->dev, "RMU: unable to get interface");
+		return -ENODEV;
+	}
+
+	ret = mv88e6xxx_rmu_send_wait(chip, port, MV88E6XXX_RMU_REQ_GET_ID, get_id, 8);
+	if (ret) {
+		dev_dbg(chip->dev, "RMU: error for command GET_ID %d index %d\n", ret,
+			chip->ds->index);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int mv88e6xxx_rmu_stats_get(struct mv88e6xxx_chip *chip, int port, uint64_t *data)
+{
+	u8 dump_mib[8] = { 0x00, 0x01, 0x00, 0x00, 0x10, 0x20, 0x00, 0x00 };
+	int ret;
+
+	if (!chip)
+		return 0;
+
+	ret = mv88e6xxx_rmu_get_id(chip, port);
+	if (ret)
+		return ret;
+
+	/* Send a GET_MIB command */
+	dump_mib[7] = port;
+	ret = mv88e6xxx_rmu_send_wait(chip, port, MV88E6XXX_RMU_REQ_DUMP_MIB, dump_mib, 8);
+	if (ret) {
+		dev_dbg(chip->dev, "RMU: error for command DUMP_MIB %d dev %d:%d\n", ret,
+			chip->ds->index, port);
+		return ret;
+	}
+
+	/* Update MIB for port */
+	if (chip->info->ops->stats_get_stats)
+		return chip->info->ops->stats_get_stats(chip, port, data);
+
+	return 0;
+}
+
+static struct mv88e6xxx_bus_ops mv88e6xxx_bus_ops = {
+	.get_rmon = mv88e6xxx_rmu_stats_get,
+};
+
+int mv88e6xxx_rmu_init(struct mv88e6xxx_chip *chip)
+{
+	dev_info(chip->dev, "RMU: setting up for switch@%d", chip->sw_addr);
+
+	init_completion(&chip->rmu.completion);
+
+	mutex_init(&chip->rmu.mutex);
+
+	chip->rmu.ops = &mv88e6xxx_bus_ops;
+
+	return 0;
+}
+
+void mv88e6xxx_rmu_master_change(struct dsa_switch *ds, const struct net_device *master,
+				 bool operational)
+{
+	struct mv88e6xxx_chip *chip = ds->priv;
+
+	if (operational)
+		chip->rmu.ops = &mv88e6xxx_bus_ops;
+	else
+		chip->rmu.ops = NULL;
+}
diff --git a/drivers/net/dsa/mv88e6xxx/rmu.h b/drivers/net/dsa/mv88e6xxx/rmu.h
new file mode 100644
index 000000000000..19be624a3ebf
--- /dev/null
+++ b/drivers/net/dsa/mv88e6xxx/rmu.h
@@ -0,0 +1,33 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Marvell 88E6xxx Switch Remote Management Unit Support
+ *
+ * Copyright (c) 2022 Mattias Forsblad <mattias.forsblad@gmail.com>
+ *
+ */
+
+#ifndef _MV88E6XXX_RMU_H_
+#define _MV88E6XXX_RMU_H_
+
+#include "chip.h"
+
+#define MV88E6XXX_RMU_MAX_RMON			64
+
+#define MV88E6XXX_RMU_REQ_GET_ID		1
+#define MV88E6XXX_RMU_REQ_DUMP_MIB		2
+
+#define MV88E6XXX_RMU_RESP_FORMAT_1		0x0001
+#define MV88E6XXX_RMU_RESP_FORMAT_2		0x0002
+#define MV88E6XXX_RMU_RESP_ERROR		0xffff
+
+#define MV88E6XXX_RMU_RESP_CODE_GOT_ID		0x0000
+#define MV88E6XXX_RMU_RESP_CODE_DUMP_MIB	0x1020
+
+int mv88e6xxx_rmu_init(struct mv88e6xxx_chip *chip);
+
+int mv88e6xxx_inband_rcv(struct dsa_switch *ds, struct sk_buff *skb, int seq_no);
+
+void mv88e6xxx_rmu_master_change(struct dsa_switch *ds, const struct net_device *master,
+				 bool operational);
+
+#endif /* _MV88E6XXX_RMU_H_ */
-- 
2.25.1

[PATCH net-next v1 3/3] rmon: Use RMU if available

[Mattias Forsblad]

If RMU is supported, use that interface to
collect rmon data.

Signed-off-by: Mattias Forsblad <mattias.forsblad@gmail.com>
---
 drivers/net/dsa/mv88e6xxx/chip.c | 41 ++++++++++++++++++++++++++------
 1 file changed, 34 insertions(+), 7 deletions(-)

diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
index 4c0510abd875..0d0241ace708 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.c
+++ b/drivers/net/dsa/mv88e6xxx/chip.c
@@ -1226,16 +1226,30 @@ static int mv88e6xxx_stats_get_stats(struct mv88e6xxx_chip *chip, int port,
 				     u16 bank1_select, u16 histogram)
 {
 	struct mv88e6xxx_hw_stat *stat;
+	int offset = 0;
+	u64 high;
 	int i, j;
 
 	for (i = 0, j = 0; i < ARRAY_SIZE(mv88e6xxx_hw_stats); i++) {
 		stat = &mv88e6xxx_hw_stats[i];
 		if (stat->type & types) {
-			mv88e6xxx_reg_lock(chip);
-			data[j] = _mv88e6xxx_get_ethtool_stat(chip, stat, port,
-							      bank1_select,
-							      histogram);
-			mv88e6xxx_reg_unlock(chip);
+			if (chip->rmu.ops && chip->rmu.ops->get_rmon &&
+			    !(stat->type & STATS_TYPE_PORT)) {
+				if (stat->type & STATS_TYPE_BANK1)
+					offset = 32;
+
+				data[j] = chip->ports[port].rmu_raw_stats[stat->reg + offset];
+				if (stat->size == 8) {
+					high = chip->ports[port].rmu_raw_stats[stat->reg + offset
+							+ 1];
+					data[j] += (high << 32);
+				}
+			} else {
+				mv88e6xxx_reg_lock(chip);
+				data[j] = _mv88e6xxx_get_ethtool_stat(chip, stat, port,
+								      bank1_select, histogram);
+				mv88e6xxx_reg_unlock(chip);
+			}
 
 			j++;
 		}
@@ -1304,8 +1318,8 @@ static void mv88e6xxx_get_stats(struct mv88e6xxx_chip *chip, int port,
 	mv88e6xxx_reg_unlock(chip);
 }
 
-static void mv88e6xxx_get_ethtool_stats(struct dsa_switch *ds, int port,
-					uint64_t *data)
+static void mv88e6xxx_get_ethtool_stats_mdio(struct dsa_switch *ds, int port,
+					     uint64_t *data)
 {
 	struct mv88e6xxx_chip *chip = ds->priv;
 	int ret;
@@ -1319,7 +1333,20 @@ static void mv88e6xxx_get_ethtool_stats(struct dsa_switch *ds, int port,
 		return;
 
 	mv88e6xxx_get_stats(chip, port, data);
+}
 
+static void mv88e6xxx_get_ethtool_stats(struct dsa_switch *ds, int port,
+					uint64_t *data)
+{
+	struct mv88e6xxx_chip *chip = ds->priv;
+
+	/* If initialization of RMU isn't available
+	 * fall back to MDIO access.
+	 */
+	if (chip->rmu.ops && chip->rmu.ops->get_rmon)
+		chip->rmu.ops->get_rmon(chip, port, data);
+	else
+		mv88e6xxx_get_ethtool_stats_mdio(ds, port, data);
 }
 
 static int mv88e6xxx_get_regs_len(struct dsa_switch *ds, int port)
-- 
2.25.1

Re: [PATCH net-next v1 2/3] dsa: mv88e6xxx: Add support for RMU in select switches

[Jakub Kicinski]

On Thu, 25 Aug 2022 11:26:28 +0200 Mattias Forsblad wrote:
> Implement support for handling RMU layer 3 frames
> including receive and transmit.

clang says:

drivers/net/dsa/mv88e6xxx/rmu.c:127:17: warning: variable 'ethhdr' set but not used [-Wunused-but-set-variable]
+        unsigned char *ethhdr;
+                       ^