net: ethernet: ti: icssg_prueth: Enable HSR Tx Tag and Rx Tag offload

Add support to offload HSR Tx Tag Insertion and Rx Tag Removal
and duplicate discard.

Support for offloading these features needs ICSSG HSR FW version
REL.HSR_1G_01.02.00.01.

Steps to offload to HSR Tx Tag Insertion and Rx Tag Removal.
-----------------------------------------------------------
Example assuming eth1, eth2 ports of ICSSG1 on AM64-EVM

  1) Delete existing HSR interface
      ip link delete hsr0

  2) Bring down the interfaces
      ip link set eth1 down
      ip link set eth2 down

  3) Configure both interfaces to have same MAC address
      ip link set dev eth2 address <ETH1_MAC_ADDRESS>

  4) Enable HSR offload for both interfaces
      ethtool -K eth1 hsr-fwd-offload on
      ethtool -K eth1 hsr-dup-offload on
      ethtool -K eth1 hsr-tag-ins-offload on
      ethtool -K eth1 hsr-tag-rm-offload on

      ethtool -K eth2 hsr-fwd-offload on
      ethtool -K eth2 hsr-dup-offload on
      ethtool -K eth2 hsr-tag-ins-offload on
      ethtool -K eth2 hsr-tag-rm-offload on

      devlink dev param set platform/icssg1-eth \
                name hsr_offload_mode \
                value true cmode runtime

  5) Bring up the interfaces
      ip link set eth1 up
      ip link set eth2 up

  6) Create HSR interface and add slave interfaces to it
      ip link add name hsr0 type hsr slave1 eth1 slave2 eth2 \
                supervision 45 version 1

  7) Add IP address to the HSR interface
      ip addr add <IP_ADDR>/24 dev hsr0

  8) Bring up the HSR interface
      ip link set hsr0 up

Switching back to Dual EMAC mode:
---------------------------------
  1) Delete HSR interface
      ip link delete hsr0

  2) Bring down the interfaces
      ip link set eth1 down
      ip link set eth2 down

  3) Disable HSR port-to-port offloading mode, packet duplication
      ethtool -K eth1 hsr-fwd-offload off
      ethtool -K eth1 hsr-dup-offload off
      ethtool -K eth1 hsr-tag-ins-offload off
      ethtool -K eth1 hsr-tag-rm-offload off

      ethtool -K eth2 hsr-fwd-offload off
      ethtool -K eth2 hsr-dup-offload off
      ethtool -K eth2 hsr-tag-ins-offload off
      ethtool -K eth2 hsr-tag-rm-offload off
      devlink dev param set platform/icssg1-eth \
                name hsr_offload_mode \
                value false cmode runtime

Note:
1) At the very least, hsr-fwd-offload must be enabled.
   Without offloading the port-to-port offload, other
   HSR offloads cannot be enabled.

2) Inorder to enable hsr-tag-ins-offload, hsr-dup-offload
   must also be enabled as these are tightly coupled in
   the firmware implementation.

Signed-off-by: Ravi Gunasekaran <r-gunasekaran@ti.com>

3 files changed, 19 insertions, 2 deletions

diff --git a/drivers/net/ethernet/ti/icssg_config.c b/drivers/net/ethernet/ti/icssg_config.c
index aea2ae8a3ae9..9d34ec0cb682 100644
--- a/drivers/net/ethernet/ti/icssg_config.c
+++ b/drivers/net/ethernet/ti/icssg_config.c
@@ -551,7 +551,9 @@ static const struct icssg_r30_cmd emac_r32_bitmask[] = {
 	{{EMAC_NONE,  0xffff4000, EMAC_NONE, EMAC_NONE}},	/* Preemption on Tx ENABLE*/
 	{{EMAC_NONE,  0xbfff0000, EMAC_NONE, EMAC_NONE}},	/* Preemption on Tx DISABLE*/
 	{{0xffff0010,  EMAC_NONE, 0xffff0010, EMAC_NONE}},	/* VLAN AWARE*/
-	{{0xffef0000,  EMAC_NONE, 0xffef0000, EMAC_NONE}}	/* VLAN UNWARE*/
+	{{0xffef0000,  EMAC_NONE, 0xffef0000, EMAC_NONE}},	/* VLAN UNWARE*/
+	{{0xffff2000, EMAC_NONE, EMAC_NONE, EMAC_NONE}},	/* HSR_RX_OFFLOAD_ENABLE */
+	{{0xdfff0000, EMAC_NONE, EMAC_NONE, EMAC_NONE}}		/* HSR_RX_OFFLOAD_DISABLE */
 };
 
 int emac_set_port_state(struct prueth_emac *emac,
diff --git a/drivers/net/ethernet/ti/icssg_config.h b/drivers/net/ethernet/ti/icssg_config.h
index ff61c66cec60..1f318884fa1b 100644
--- a/drivers/net/ethernet/ti/icssg_config.h
+++ b/drivers/net/ethernet/ti/icssg_config.h
@@ -81,6 +81,8 @@ enum icssg_port_state_cmd {
 	ICSSG_EMAC_PORT_PREMPT_TX_DISABLE,
 	ICSSG_EMAC_PORT_VLAN_AWARE_ENABLE,
 	ICSSG_EMAC_PORT_VLAN_AWARE_DISABLE,
+	ICSSG_EMAC_HSR_RX_OFFLOAD_ENABLE,
+	ICSSG_EMAC_HSR_RX_OFFLOAD_DISABLE,
 	ICSSG_EMAC_PORT_MAX_COMMANDS
 };
 
diff --git a/drivers/net/ethernet/ti/icssg_prueth.c b/drivers/net/ethernet/ti/icssg_prueth.c
index 613b78775580..b6b075bf64d0 100644
--- a/drivers/net/ethernet/ti/icssg_prueth.c
+++ b/drivers/net/ethernet/ti/icssg_prueth.c
@@ -67,7 +67,9 @@
 #define DEFAULT_UNTAG_MASK	1
 
 #define NETIF_PRUETH_HSR_OFFLOAD	(NETIF_F_HW_HSR_FWD | \
-					 NETIF_F_HW_HSR_DUP)
+					 NETIF_F_HW_HSR_DUP | \
+					 NETIF_F_HW_HSR_TAG_INS | \
+					 NETIF_F_HW_HSR_TAG_RM)
 
 /* CTRLMMR_ICSSG_RGMII_CTRL register bits */
 #define ICSSG_CTRL_RGMII_ID_MODE		BIT(24)
@@ -75,6 +77,7 @@
 #define IEP_DEFAULT_CYCLE_TIME_NS	1000000	/* 1 ms */
 
 #define PRUETH_UNDIRECTED_PKT_DST_TAG	0
+#define PRUETH_UNDIRECTED_PKT_TAG_INS	BIT(30)
 
 static void prueth_cleanup_rx_chns(struct prueth_emac *emac,
 				   struct prueth_rx_chn *rx_chn,
@@ -875,6 +878,9 @@ static enum netdev_tx emac_ndo_start_xmit(struct sk_buff *skb, struct net_device
 	if (prueth->is_hsr_offload_mode && (ndev->features & NETIF_F_HW_HSR_DUP))
 		dst_tag_id = PRUETH_UNDIRECTED_PKT_DST_TAG;
 
+	if (prueth->is_hsr_offload_mode && (ndev->features & NETIF_F_HW_HSR_TAG_INS))
+		epib[1] |= PRUETH_UNDIRECTED_PKT_TAG_INS;
+
 	cppi5_desc_set_tags_ids(&first_desc->hdr, 0, dst_tag_id);
 	k3_udma_glue_tx_dma_to_cppi5_addr(tx_chn->tx_chn, &buf_dma);
 	cppi5_hdesc_attach_buf(first_desc, buf_dma, pkt_len, buf_dma, pkt_len);
@@ -1678,6 +1684,13 @@ static int emac_ndo_open(struct net_device *ndev)
 		}
 	}
 
+	if (prueth->is_hsr_offload_mode) {
+		if (ndev->features & NETIF_F_HW_HSR_TAG_RM)
+			emac_set_port_state(emac, ICSSG_EMAC_HSR_RX_OFFLOAD_ENABLE);
+		else
+			emac_set_port_state(emac, ICSSG_EMAC_HSR_RX_OFFLOAD_DISABLE);
+	}
+
 	flow_cfg = emac->dram.va + ICSSG_CONFIG_OFFSET + PSI_L_REGULAR_FLOW_ID_BASE_OFFSET;
 	writew(emac->rx_flow_id_base, &flow_cfg->rx_base_flow);
 	ret = emac_fdb_flow_id_updated(emac);