net: atlantic: loopback tests via private flags

Here we add a number of ethtool private flags
to allow enabling various loopbacks on HW.

Thats useful for verification and bringup works.
Signed-off-by: Igor Russkikh <irusskikh@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/networking/device_drivers/aquantia/atlantic.txt

@@ -325,6 +325,31 @@ Supported ethtool options
  Example:
  ethtool -N eth0 flow-type udp4 action 0 loc 32
 
+ Private flags (testing)
+ ---------------------------------
+
+ Atlantic driver supports private flags for hardware custom features:
+
+	$ ethtool --show-priv-flags ethX
+
+	Private flags for ethX:
+	DMASystemLoopback  : off
+	PKTSystemLoopback  : off
+	DMANetworkLoopback : off
+	PHYInternalLoopback: off
+	PHYExternalLoopback: off
+
+ Example:
+
+	$ ethtool --set-priv-flags ethX DMASystemLoopback on
+
+ DMASystemLoopback:   DMA Host loopback.
+ PKTSystemLoopback:   Packet buffer host loopback.
+ DMANetworkLoopback:  Network side loopback on DMA block.
+ PHYInternalLoopback: Internal loopback on Phy.
+ PHYExternalLoopback: External loopback on Phy (with loopback ethernet cable).
+
+
 Command Line Parameters
 =======================
 The following command line parameters are available on atlantic driver:

drivers/net/ethernet/aquantia/atlantic/aq_ethtool.c

@@ -92,6 +92,14 @@ static const char aq_ethtool_queue_stat_names[][ETH_GSTRING_LEN] = {
 	"Queue[%d] InErrors",
 };
 
+static const char aq_ethtool_priv_flag_names[][ETH_GSTRING_LEN] = {
+	"DMASystemLoopback",
+	"PKTSystemLoopback",
+	"DMANetworkLoopback",
+	"PHYInternalLoopback",
+	"PHYExternalLoopback",
+};
+
 static void aq_ethtool_stats(struct net_device *ndev,
 			     struct ethtool_stats *stats, u64 *data)
 {
@@ -137,7 +145,8 @@ static void aq_ethtool_get_strings(struct net_device *ndev,
 	struct aq_nic_cfg_s *cfg = aq_nic_get_cfg(aq_nic);
 	u8 *p = data;
 
-	if (stringset == ETH_SS_STATS) {
+	switch (stringset) {
+	case ETH_SS_STATS:
 		memcpy(p, aq_ethtool_stat_names,
 		       sizeof(aq_ethtool_stat_names));
 		p = p + sizeof(aq_ethtool_stat_names);
@@ -150,6 +159,11 @@ static void aq_ethtool_get_strings(struct net_device *ndev,
 				p += ETH_GSTRING_LEN;
 			}
 		}
+		break;
+	case ETH_SS_PRIV_FLAGS:
+		memcpy(p, aq_ethtool_priv_flag_names,
+		       sizeof(aq_ethtool_priv_flag_names));
+		break;
 	}
 }
 
@@ -193,6 +207,9 @@ static int aq_ethtool_get_sset_count(struct net_device *ndev, int stringset)
 		ret = ARRAY_SIZE(aq_ethtool_stat_names) +
 			cfg->vecs * ARRAY_SIZE(aq_ethtool_queue_stat_names);
 		break;
+	case ETH_SS_PRIV_FLAGS:
+		ret = ARRAY_SIZE(aq_ethtool_priv_flag_names);
+		break;
 	default:
 		ret = -EOPNOTSUPP;
 	}
@@ -650,6 +667,40 @@ static void aq_set_msg_level(struct net_device *ndev, u32 data)
 	aq_nic->msg_enable = data;
 }
 
+u32 aq_ethtool_get_priv_flags(struct net_device *ndev)
+{
+	struct aq_nic_s *aq_nic = netdev_priv(ndev);
+
+	return aq_nic->aq_nic_cfg.priv_flags;
+}
+
+int aq_ethtool_set_priv_flags(struct net_device *ndev, u32 flags)
+{
+	struct aq_nic_s *aq_nic = netdev_priv(ndev);
+	struct aq_nic_cfg_s *cfg;
+	u32 priv_flags;
+
+	cfg = aq_nic_get_cfg(aq_nic);
+	priv_flags = cfg->priv_flags;
+
+	if (flags & ~AQ_PRIV_FLAGS_MASK)
+		return -EOPNOTSUPP;
+
+	cfg->priv_flags = flags;
+
+	if ((priv_flags ^ flags) & BIT(AQ_HW_LOOPBACK_DMA_NET)) {
+		if (netif_running(ndev)) {
+			dev_close(ndev);
+
+			dev_open(ndev, NULL);
+		}
+	} else if ((priv_flags ^ flags) & AQ_HW_LOOPBACK_MASK) {
+		aq_nic_set_loopback(aq_nic);
+	}
+
+	return 0;
+}
+
 const struct ethtool_ops aq_ethtool_ops = {
 	.get_link            = aq_ethtool_get_link,
 	.get_regs_len        = aq_ethtool_get_regs_len,
@@ -676,6 +727,8 @@ const struct ethtool_ops aq_ethtool_ops = {
 	.set_msglevel        = aq_set_msg_level,
 	.get_sset_count      = aq_ethtool_get_sset_count,
 	.get_ethtool_stats   = aq_ethtool_stats,
+	.get_priv_flags      = aq_ethtool_get_priv_flags,
+	.set_priv_flags      = aq_ethtool_set_priv_flags,
 	.get_link_ksettings  = aq_ethtool_get_link_ksettings,
 	.set_link_ksettings  = aq_ethtool_set_link_ksettings,
 	.get_coalesce	     = aq_ethtool_get_coalesce,

drivers/net/ethernet/aquantia/atlantic/aq_ethtool.h

@@ -12,5 +12,6 @@
 #include "aq_common.h"
 
 extern const struct ethtool_ops aq_ethtool_ops;
+#define AQ_PRIV_FLAGS_MASK   (AQ_HW_LOOPBACK_MASK)
 
 #endif /* AQ_ETHTOOL_H */

drivers/net/ethernet/aquantia/atlantic/aq_hw.h

@@ -122,6 +122,20 @@ struct aq_stats_s {
 #define AQ_HW_LED_BLINK    0x2U
 #define AQ_HW_LED_DEFAULT  0x0U
 
+enum aq_priv_flags {
+	AQ_HW_LOOPBACK_DMA_SYS,
+	AQ_HW_LOOPBACK_PKT_SYS,
+	AQ_HW_LOOPBACK_DMA_NET,
+	AQ_HW_LOOPBACK_PHYINT_SYS,
+	AQ_HW_LOOPBACK_PHYEXT_SYS,
+};
+
+#define AQ_HW_LOOPBACK_MASK	(BIT(AQ_HW_LOOPBACK_DMA_SYS) |\
+				 BIT(AQ_HW_LOOPBACK_PKT_SYS) |\
+				 BIT(AQ_HW_LOOPBACK_DMA_NET) |\
+				 BIT(AQ_HW_LOOPBACK_PHYINT_SYS) |\
+				 BIT(AQ_HW_LOOPBACK_PHYEXT_SYS))
+
 struct aq_hw_s {
 	atomic_t flags;
 	u8 rbl_enabled:1;
@@ -280,6 +294,8 @@ struct aq_hw_ops {
 			    u64 *timestamp);
 
 	int (*hw_set_fc)(struct aq_hw_s *self, u32 fc, u32 tc);
+
+	int (*hw_set_loopback)(struct aq_hw_s *self, u32 mode, bool enable);
 };
 
 struct aq_fw_ops {
@@ -310,6 +326,8 @@ struct aq_fw_ops {
 
 	int (*led_control)(struct aq_hw_s *self, u32 mode);
 
+	int (*set_phyloopback)(struct aq_hw_s *self, u32 mode, bool enable);
+
 	int (*set_power)(struct aq_hw_s *self, unsigned int power_state,
 			 u8 *mac);
 

drivers/net/ethernet/aquantia/atlantic/aq_nic.c

@@ -406,6 +406,8 @@ int aq_nic_start(struct aq_nic_s *self)
 
 	INIT_WORK(&self->service_task, aq_nic_service_task);
 
+	aq_nic_set_loopback(self);
+
 	timer_setup(&self->service_timer, aq_nic_service_timer_cb, 0);
 	aq_nic_service_timer_cb(&self->service_timer);
 
@@ -625,6 +627,11 @@ int aq_nic_xmit(struct aq_nic_s *self, struct sk_buff *skb)
 
 	aq_ring_update_queue_state(ring);
 
+	if (self->aq_nic_cfg.priv_flags & BIT(AQ_HW_LOOPBACK_DMA_NET)) {
+		err = NETDEV_TX_BUSY;
+		goto err_exit;
+	}
+
 	/* Above status update may stop the queue. Check this. */
 	if (__netif_subqueue_stopped(self->ndev, ring->idx)) {
 		err = NETDEV_TX_BUSY;
@@ -973,6 +980,44 @@ u32 aq_nic_get_fw_version(struct aq_nic_s *self)
 	return fw_version;
 }
 
+int aq_nic_set_loopback(struct aq_nic_s *self)
+{
+	struct aq_nic_cfg_s *cfg = &self->aq_nic_cfg;
+
+	if (!self->aq_hw_ops->hw_set_loopback ||
+	    !self->aq_fw_ops->set_phyloopback)
+		return -ENOTSUPP;
+
+	mutex_lock(&self->fwreq_mutex);
+	self->aq_hw_ops->hw_set_loopback(self->aq_hw,
+					 AQ_HW_LOOPBACK_DMA_SYS,
+					 !!(cfg->priv_flags &
+					    BIT(AQ_HW_LOOPBACK_DMA_SYS)));
+
+	self->aq_hw_ops->hw_set_loopback(self->aq_hw,
+					 AQ_HW_LOOPBACK_PKT_SYS,
+					 !!(cfg->priv_flags &
+					    BIT(AQ_HW_LOOPBACK_PKT_SYS)));
+
+	self->aq_hw_ops->hw_set_loopback(self->aq_hw,
+					 AQ_HW_LOOPBACK_DMA_NET,
+					 !!(cfg->priv_flags &
+					    BIT(AQ_HW_LOOPBACK_DMA_NET)));
+
+	self->aq_fw_ops->set_phyloopback(self->aq_hw,
+					 AQ_HW_LOOPBACK_PHYINT_SYS,
+					 !!(cfg->priv_flags &
+					    BIT(AQ_HW_LOOPBACK_PHYINT_SYS)));
+
+	self->aq_fw_ops->set_phyloopback(self->aq_hw,
+					 AQ_HW_LOOPBACK_PHYEXT_SYS,
+					 !!(cfg->priv_flags &
+					    BIT(AQ_HW_LOOPBACK_PHYEXT_SYS)));
+	mutex_unlock(&self->fwreq_mutex);
+
+	return 0;
+}
+
 int aq_nic_stop(struct aq_nic_s *self)
 {
 	struct aq_vec_s *aq_vec = NULL;

drivers/net/ethernet/aquantia/atlantic/aq_nic.h

@@ -46,6 +46,7 @@ struct aq_nic_cfg_s {
 	bool is_polling;
 	bool is_rss;
 	bool is_lro;
+	u32 priv_flags;
 	u8  tcs;
 	struct aq_rss_parameters aq_rss;
 	u32 eee_speeds;
@@ -158,6 +159,7 @@ int aq_nic_set_link_ksettings(struct aq_nic_s *self,
 			      const struct ethtool_link_ksettings *cmd);
 struct aq_nic_cfg_s *aq_nic_get_cfg(struct aq_nic_s *self);
 u32 aq_nic_get_fw_version(struct aq_nic_s *self);
+int aq_nic_set_loopback(struct aq_nic_s *self);
 int aq_nic_update_interrupt_moderation_settings(struct aq_nic_s *self);
 void aq_nic_shutdown(struct aq_nic_s *self);
 u8 aq_nic_reserve_filter(struct aq_nic_s *self, enum aq_rx_filter_type type);

drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_b0.c

@@ -1427,6 +1427,30 @@ static int hw_atl_b0_hw_vlan_ctrl(struct aq_hw_s *self, bool enable)
 	return aq_hw_err_from_flags(self);
 }
 
+static int hw_atl_b0_set_loopback(struct aq_hw_s *self, u32 mode, bool enable)
+{
+	switch (mode) {
+	case AQ_HW_LOOPBACK_DMA_SYS:
+		hw_atl_tpb_tx_dma_sys_lbk_en_set(self, enable);
+		hw_atl_rpb_dma_sys_lbk_set(self, enable);
+		break;
+	case AQ_HW_LOOPBACK_PKT_SYS:
+		hw_atl_tpo_tx_pkt_sys_lbk_en_set(self, enable);
+		hw_atl_rpf_tpo_to_rpf_sys_lbk_set(self, enable);
+		break;
+	case AQ_HW_LOOPBACK_DMA_NET:
+		hw_atl_rpf_vlan_prom_mode_en_set(self, enable);
+		hw_atl_rpfl2promiscuous_mode_en_set(self, enable);
+		hw_atl_tpb_tx_tx_clk_gate_en_set(self, !enable);
+		hw_atl_tpb_tx_dma_net_lbk_en_set(self, enable);
+		hw_atl_rpb_dma_net_lbk_set(self, enable);
+		break;
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
 const struct aq_hw_ops hw_atl_ops_b0 = {
 	.hw_set_mac_address   = hw_atl_b0_hw_mac_addr_set,
 	.hw_init              = hw_atl_b0_hw_init,
@@ -1481,5 +1505,9 @@ const struct aq_hw_ops hw_atl_ops_b0 = {
 	.rx_extract_ts           = hw_atl_b0_rx_extract_ts,
 	.extract_hwts            = hw_atl_b0_extract_hwts,
 	.hw_set_offload          = hw_atl_b0_hw_offload_set,
+	.hw_get_hw_stats         = hw_atl_utils_get_hw_stats,
+	.hw_get_fw_version       = hw_atl_utils_get_fw_version,
+	.hw_set_offload          = hw_atl_b0_hw_offload_set,
+	.hw_set_loopback         = hw_atl_b0_set_loopback,
 	.hw_set_fc               = hw_atl_b0_set_fc,
 };

drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_llh.c

@@ -563,6 +563,13 @@ void hw_atl_rpb_dma_sys_lbk_set(struct aq_hw_s *aq_hw, u32 dma_sys_lbk)
 			    HW_ATL_RPB_DMA_SYS_LBK_SHIFT, dma_sys_lbk);
 }
 
+void hw_atl_rpb_dma_net_lbk_set(struct aq_hw_s *aq_hw, u32 dma_net_lbk)
+{
+	aq_hw_write_reg_bit(aq_hw, HW_ATL_RPB_DMA_NET_LBK_ADR,
+			    HW_ATL_RPB_DMA_NET_LBK_MSK,
+			    HW_ATL_RPB_DMA_NET_LBK_SHIFT, dma_net_lbk);
+}
+
 void hw_atl_rpb_rpf_rx_traf_class_mode_set(struct aq_hw_s *aq_hw,
 					   u32 rx_traf_class_mode)
 {
@@ -1341,7 +1348,26 @@ void hw_atl_tpb_tx_dma_sys_lbk_en_set(struct aq_hw_s *aq_hw, u32 tx_dma_sys_lbk_
 			    tx_dma_sys_lbk_en);
 }
 
+void hw_atl_tpb_tx_dma_net_lbk_en_set(struct aq_hw_s *aq_hw,
+				      u32 tx_dma_net_lbk_en)
+{
+	aq_hw_write_reg_bit(aq_hw, HW_ATL_TPB_DMA_NET_LBK_ADR,
+			    HW_ATL_TPB_DMA_NET_LBK_MSK,
+			    HW_ATL_TPB_DMA_NET_LBK_SHIFT,
+			    tx_dma_net_lbk_en);
+}
+
+void hw_atl_tpb_tx_tx_clk_gate_en_set(struct aq_hw_s *aq_hw,
+				      u32 tx_clk_gate_en)
+{
+	aq_hw_write_reg_bit(aq_hw, HW_ATL_TPB_TX_CLK_GATE_EN_ADR,
+			    HW_ATL_TPB_TX_CLK_GATE_EN_MSK,
+			    HW_ATL_TPB_TX_CLK_GATE_EN_SHIFT,
+			    tx_clk_gate_en);
+}
+
 void hw_atl_tpb_tx_pkt_buff_size_per_tc_set(struct aq_hw_s *aq_hw,
+
 					    u32 tx_pkt_buff_size_per_tc, u32 buffer)
 {
 	aq_hw_write_reg_bit(aq_hw, HW_ATL_TPB_TXBBUF_SIZE_ADR(buffer),

drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_llh.h

@@ -288,6 +288,9 @@ void hw_atl_reg_glb_cpu_scratch_scp_set(struct aq_hw_s *aq_hw,
 /* set dma system loopback */
 void hw_atl_rpb_dma_sys_lbk_set(struct aq_hw_s *aq_hw, u32 dma_sys_lbk);
 
+/* set dma network loopback */
+void hw_atl_rpb_dma_net_lbk_set(struct aq_hw_s *aq_hw, u32 dma_net_lbk);
+
 /* set rx traffic class mode */
 void hw_atl_rpb_rpf_rx_traf_class_mode_set(struct aq_hw_s *aq_hw,
 					   u32 rx_traf_class_mode);
@@ -629,6 +632,14 @@ void hw_atl_tpb_tx_buff_lo_threshold_per_tc_set(struct aq_hw_s *aq_hw,
 /* set tx dma system loopback enable */
 void hw_atl_tpb_tx_dma_sys_lbk_en_set(struct aq_hw_s *aq_hw, u32 tx_dma_sys_lbk_en);
 
+/* set tx dma network loopback enable */
+void hw_atl_tpb_tx_dma_net_lbk_en_set(struct aq_hw_s *aq_hw,
+				      u32 tx_dma_net_lbk_en);
+
+/* set tx clock gating enable */
+void hw_atl_tpb_tx_tx_clk_gate_en_set(struct aq_hw_s *aq_hw,
+				      u32 tx_clk_gate_en);
+
 /* set tx packet buffer size (per tc) */
 void hw_atl_tpb_tx_pkt_buff_size_per_tc_set(struct aq_hw_s *aq_hw,
 					    u32 tx_pkt_buff_size_per_tc,

drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_llh_internal.h

@@ -554,6 +554,24 @@
 /* default value of bitfield dma_sys_loopback */
 #define HW_ATL_RPB_DMA_SYS_LBK_DEFAULT 0x0
 
+/* rx dma_net_loopback bitfield definitions
+ * preprocessor definitions for the bitfield "dma_net_loopback".
+ * port="pif_rpb_dma_net_lbk_i"
+ */
+
+/* register address for bitfield dma_net_loopback */
+#define HW_ATL_RPB_DMA_NET_LBK_ADR 0x00005000
+/* bitmask for bitfield dma_net_loopback */
+#define HW_ATL_RPB_DMA_NET_LBK_MSK 0x00000010
+/* inverted bitmask for bitfield dma_net_loopback */
+#define HW_ATL_RPB_DMA_NET_LBK_MSKN 0xffffffef
+/* lower bit position of bitfield dma_net_loopback */
+#define HW_ATL_RPB_DMA_NET_LBK_SHIFT 4
+/* width of bitfield dma_net_loopback */
+#define HW_ATL_RPB_DMA_NET_LBK_WIDTH 1
+/* default value of bitfield dma_net_loopback */
+#define HW_ATL_RPB_DMA_NET_LBK_DEFAULT 0x0
+
 /* rx rx_tc_mode bitfield definitions
  * preprocessor definitions for the bitfield "rx_tc_mode".
  * port="pif_rpb_rx_tc_mode_i,pif_rpf_rx_tc_mode_i"
@@ -2107,6 +2125,24 @@
 /* default value of bitfield dma_sys_loopback */
 #define HW_ATL_TPB_DMA_SYS_LBK_DEFAULT 0x0
 
+/* tx dma_net_loopback bitfield definitions
+ * preprocessor definitions for the bitfield "dma_net_loopback".
+ * port="pif_tpb_dma_net_lbk_i"
+ */
+
+/* register address for bitfield dma_net_loopback */
+#define HW_ATL_TPB_DMA_NET_LBK_ADR 0x00007000
+/* bitmask for bitfield dma_net_loopback */
+#define HW_ATL_TPB_DMA_NET_LBK_MSK 0x00000010
+/* inverted bitmask for bitfield dma_net_loopback */
+#define HW_ATL_TPB_DMA_NET_LBK_MSKN 0xffffffef
+/* lower bit position of bitfield dma_net_loopback */
+#define HW_ATL_TPB_DMA_NET_LBK_SHIFT 4
+/* width of bitfield dma_net_loopback */
+#define HW_ATL_TPB_DMA_NET_LBK_WIDTH 1
+/* default value of bitfield dma_net_loopback */
+#define HW_ATL_TPB_DMA_NET_LBK_DEFAULT 0x0
+
 /* tx tx{b}_buf_size[7:0] bitfield definitions
  * preprocessor definitions for the bitfield "tx{b}_buf_size[7:0]".
  * parameter: buffer {b} | stride size 0x10 | range [0, 7]
@@ -2144,6 +2180,24 @@
 /* default value of bitfield tx_scp_ins_en */
 #define HW_ATL_TPB_TX_SCP_INS_EN_DEFAULT 0x0
 
+/* tx tx_clk_gate_en bitfield definitions
+ * preprocessor definitions for the bitfield "tx_clk_gate_en".
+ * port="pif_tpb_clk_gate_en_i"
+ */
+
+/* register address for bitfield tx_clk_gate_en */
+#define HW_ATL_TPB_TX_CLK_GATE_EN_ADR 0x00007900
+/* bitmask for bitfield tx_clk_gate_en */
+#define HW_ATL_TPB_TX_CLK_GATE_EN_MSK 0x00000010
+/* inverted bitmask for bitfield tx_clk_gate_en */
+#define HW_ATL_TPB_TX_CLK_GATE_EN_MSKN 0xffffffef
+/* lower bit position of bitfield tx_clk_gate_en */
+#define HW_ATL_TPB_TX_CLK_GATE_EN_SHIFT 4
+/* width of bitfield tx_clk_gate_en */
+#define HW_ATL_TPB_TX_CLK_GATE_EN_WIDTH 1
+/* default value of bitfield tx_clk_gate_en */
+#define HW_ATL_TPB_TX_CLK_GATE_EN_DEFAULT 0x1
+
 /* tx ipv4_chk_en bitfield definitions
  * preprocessor definitions for the bitfield "ipv4_chk_en".
  * port="pif_tpo_ipv4_chk_en_i"

drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_utils_fw2x.c

@@ -42,6 +42,9 @@
 #define HW_ATL_FW2X_CTRL_PAUSE            BIT(CTRL_PAUSE)
 #define HW_ATL_FW2X_CTRL_TEMPERATURE      BIT(CTRL_TEMPERATURE)
 #define HW_ATL_FW2X_CTRL_ASYMMETRIC_PAUSE BIT(CTRL_ASYMMETRIC_PAUSE)
+#define HW_ATL_FW2X_CTRL_INT_LOOPBACK     BIT(CTRL_INT_LOOPBACK)
+#define HW_ATL_FW2X_CTRL_EXT_LOOPBACK     BIT(CTRL_EXT_LOOPBACK)
+#define HW_ATL_FW2X_CTRL_DOWNSHIFT        BIT(CTRL_DOWNSHIFT)
 #define HW_ATL_FW2X_CTRL_FORCE_RECONNECT  BIT(CTRL_FORCE_RECONNECT)
 
 #define HW_ATL_FW2X_CAP_EEE_1G_MASK      BIT(CAPS_HI_1000BASET_FD_EEE)
@@ -53,6 +56,7 @@
 #define HAL_ATLANTIC_UTILS_FW2X_MSG_WOL  0x0E
 
 #define HW_ATL_FW_VER_LED                0x03010026U
+#define HW_ATL_FW_VER_MEDIA_CONTROL      0x0301005aU
 
 struct __packed fw2x_msg_wol_pattern {
 	u8 mask[16];
@@ -539,6 +543,33 @@ static u32 aq_fw2x_get_flow_control(struct aq_hw_s *self, u32 *fcmode)
 	return 0;
 }
 
+static int aq_fw2x_set_phyloopback(struct aq_hw_s *self, u32 mode, bool enable)
+{
+	u32 mpi_opts;
+
+	switch (mode) {
+	case AQ_HW_LOOPBACK_PHYINT_SYS:
+		mpi_opts = aq_hw_read_reg(self, HW_ATL_FW2X_MPI_CONTROL2_ADDR);
+		if (enable)
+			mpi_opts |= HW_ATL_FW2X_CTRL_INT_LOOPBACK;
+		else
+			mpi_opts &= ~HW_ATL_FW2X_CTRL_INT_LOOPBACK;
+		aq_hw_write_reg(self, HW_ATL_FW2X_MPI_CONTROL2_ADDR, mpi_opts);
+		break;
+	case AQ_HW_LOOPBACK_PHYEXT_SYS:
+		mpi_opts = aq_hw_read_reg(self, HW_ATL_FW2X_MPI_CONTROL2_ADDR);
+		if (enable)
+			mpi_opts |= HW_ATL_FW2X_CTRL_EXT_LOOPBACK;
+		else
+			mpi_opts &= ~HW_ATL_FW2X_CTRL_EXT_LOOPBACK;
+		aq_hw_write_reg(self, HW_ATL_FW2X_MPI_CONTROL2_ADDR, mpi_opts);
+		break;
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
 static u32 aq_fw2x_mbox_get(struct aq_hw_s *self)
 {
 	return aq_hw_read_reg(self, HW_ATL_FW2X_MPI_MBOX_ADDR);
@@ -586,4 +617,5 @@ const struct aq_fw_ops aq_fw_2x_ops = {
 	.send_fw_request    = aq_fw2x_send_fw_request,
 	.enable_ptp         = aq_fw3x_enable_ptp,
 	.led_control        = aq_fw2x_led_control,
+	.set_phyloopback    = aq_fw2x_set_phyloopback,
 };