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[iwl-next] ixgbe: allow toggling loopback mode via ndo_set_features callback

Message ID 20230601074621.14755-1-magnus.karlsson@gmail.com (mailing list archive)
State Awaiting Upstream
Delegated to: Netdev Maintainers
Headers show
Series [iwl-next] ixgbe: allow toggling loopback mode via ndo_set_features callback | expand

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Commit Message

Magnus Karlsson June 1, 2023, 7:46 a.m. UTC 
From: Hao Ma <hao.ma@intel.com>

Add support for NETIF_F_LOOPBACK. This feature can be set via: $
ethtool -K eth0 loopback <on|off>. This sets the MAC Tx->Rx loopback
used by selftests/bpf/xskxceiver.

Signed-off-by: Hao Ma <hao.ma@intel.com>
---
 .../net/ethernet/intel/ixgbe/ixgbe_common.c   |  4 +-
 drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 73 +++++++++++++++++++
 drivers/net/ethernet/intel/ixgbe/ixgbe_type.h |  1 +
 3 files changed, 76 insertions(+), 2 deletions(-)


base-commit: 735c9ee9a374769b78c716de3c19a6c9440ede85

Comments

Fijalkowski, Maciej June 1, 2023, 9:53 a.m. UTC | #1 
On Thu, Jun 01, 2023 at 09:46:21AM +0200, Magnus Karlsson wrote:
> From: Hao Ma <hao.ma@intel.com>
> 
> Add support for NETIF_F_LOOPBACK. This feature can be set via: $
> ethtool -K eth0 loopback <on|off>. This sets the MAC Tx->Rx loopback
> used by selftests/bpf/xskxceiver.
> 
> Signed-off-by: Hao Ma <hao.ma@intel.com>
> ---
>  .../net/ethernet/intel/ixgbe/ixgbe_common.c   |  4 +-
>  drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 73 +++++++++++++++++++
>  drivers/net/ethernet/intel/ixgbe/ixgbe_type.h |  1 +
>  3 files changed, 76 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
> index 878dd8dff528..b8998a56ad24 100644
> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
> @@ -3337,7 +3337,7 @@ s32 ixgbe_check_mac_link_generic(struct ixgbe_hw *hw, ixgbe_link_speed *speed,
>  
>  	if (link_up_wait_to_complete) {
>  		for (i = 0; i < IXGBE_LINK_UP_TIME; i++) {
> -			if (links_reg & IXGBE_LINKS_UP) {
> +			if (links_reg & IXGBE_LINKS_UP || hw->loopback_on) {
>  				*link_up = true;
>  				break;
>  			} else {
> @@ -3347,7 +3347,7 @@ s32 ixgbe_check_mac_link_generic(struct ixgbe_hw *hw, ixgbe_link_speed *speed,
>  			links_reg = IXGBE_READ_REG(hw, IXGBE_LINKS);
>  		}
>  	} else {
> -		if (links_reg & IXGBE_LINKS_UP) {
> +		if (links_reg & IXGBE_LINKS_UP || hw->loopback_on) {
>  			if (crosstalk_fix_active) {
>  				/* Check the link state again after a delay
>  				 * to filter out spurious link up
> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> index 5d83c887a3fc..70b34b7b5cb0 100644
> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> @@ -8864,6 +8864,57 @@ netdev_tx_t ixgbe_xmit_frame_ring(struct sk_buff *skb,
>  	return NETDEV_TX_OK;
>  }
>  
> +static int ixgbe_force_loopback(struct ixgbe_adapter *adapter, bool on)
> +{	struct ixgbe_hw *hw = &adapter->hw;
> +	u32 reg_data;
> +
> +	hw->loopback_on = on;
> +	/* Setup MAC loopback */
> +	reg_data = IXGBE_READ_REG(hw, IXGBE_HLREG0);
> +	if (on)
> +		reg_data |= IXGBE_HLREG0_LPBK;
> +	else
> +		reg_data &= ~IXGBE_HLREG0_LPBK;
> +	IXGBE_WRITE_REG(hw, IXGBE_HLREG0, reg_data);
> +
> +	reg_data = IXGBE_READ_REG(hw, IXGBE_FCTRL);
> +	if (on)
> +		reg_data |= IXGBE_FCTRL_SBP | IXGBE_FCTRL_MPE;
> +	else
> +		reg_data &= ~(IXGBE_FCTRL_SBP | IXGBE_FCTRL_MPE);
> +	reg_data &= ~(IXGBE_FCTRL_BAM);
> +	IXGBE_WRITE_REG(hw, IXGBE_FCTRL, reg_data);
> +
> +	/* X540 and X550 needs to set the MACC.FLU bit to force link up */
> +	switch (adapter->hw.mac.type) {
> +	case ixgbe_mac_X540:
> +	case ixgbe_mac_X550:
> +	case ixgbe_mac_X550EM_x:
> +	case ixgbe_mac_x550em_a:
> +		reg_data = IXGBE_READ_REG(hw, IXGBE_MACC);
> +		if (on)
> +			reg_data |= IXGBE_MACC_FLU;
> +		else
> +			reg_data &= ~IXGBE_MACC_FLU;
> +		IXGBE_WRITE_REG(hw, IXGBE_MACC, reg_data);
> +		break;
> +	default:
> +		if (hw->mac.orig_autoc) {
> +			if (on)
> +				reg_data = hw->mac.orig_autoc | IXGBE_AUTOC_FLU;
> +			else
> +				reg_data = hw->mac.orig_autoc & ~IXGBE_AUTOC_FLU;
> +			IXGBE_WRITE_REG(hw, IXGBE_AUTOC, reg_data);
> +		} else {
> +			return 10;
> +		}
> +	}
> +
> +	IXGBE_WRITE_FLUSH(hw);
> +
> +	return 0;
> +}
> +
>  static netdev_tx_t __ixgbe_xmit_frame(struct sk_buff *skb,
>  				      struct net_device *netdev,
>  				      struct ixgbe_ring *ring)
> @@ -9915,6 +9966,15 @@ static int ixgbe_set_features(struct net_device *netdev,
>  	if (changed & NETIF_F_RXALL)
>  		need_reset = true;
>  
> +	if (changed & NETIF_F_LOOPBACK) {
> +		if (features & NETIF_F_LOOPBACK) {
> +			ixgbe_force_loopback(adapter, true);
> +		} else {
> +			ixgbe_force_loopback(adapter, false);
> +			need_reset = true;
> +			}

on ice we just do:

	if (changed & NETIF_F_LOOPBACK)
		ret = ice_set_loopback(vsi, !!(features & NETIF_F_LOOPBACK));

don't you need to set need_reset to true as well when you are disabling
loopback in order to clear appropriate bits from registers?

> +	}
> +
>  	netdev->features = features;
>  
>  	if ((changed & NETIF_F_HW_L2FW_DOFFLOAD) && adapter->num_rx_pools > 1)
> @@ -10286,6 +10346,17 @@ static int ixgbe_xdp_setup(struct net_device *dev, struct bpf_prog *prog)
>  			/* Wait until ndo_xsk_wakeup completes. */
>  			synchronize_rcu();
>  		err = ixgbe_setup_tc(dev, adapter->hw_tcs);
> +		if (adapter->hw.loopback_on) {
> +			u32 reg_data;
> +
> +			reg_data = IXGBE_READ_REG(&adapter->hw, IXGBE_HLREG0);
> +			reg_data |= IXGBE_HLREG0_LPBK;
> +			IXGBE_WRITE_REG(&adapter->hw, IXGBE_HLREG0, reg_data);
> +
> +			reg_data = IXGBE_READ_REG(&adapter->hw, IXGBE_MACC);
> +			reg_data |= IXGBE_MACC_FLU;
> +			IXGBE_WRITE_REG(&adapter->hw, IXGBE_MACC, reg_data);

can you explain why do you need to set loopback bits again after they were
set on ixgbe_force_loopback() ? are they not preserved after downing an
interface?

> +		}
>  
>  		if (err)
>  			return -EINVAL;
> @@ -10969,6 +11040,8 @@ static int ixgbe_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
>  	if (hw->mac.type >= ixgbe_mac_82599EB)
>  		netdev->features |= NETIF_F_SCTP_CRC | NETIF_F_GSO_UDP_L4;
>  
> +	netdev->features |= NETIF_F_LOOPBACK;
> +
>  #ifdef CONFIG_IXGBE_IPSEC
>  #define IXGBE_ESP_FEATURES	(NETIF_F_HW_ESP | \
>  				 NETIF_F_HW_ESP_TX_CSUM | \
> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h b/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
> index 2b00db92b08f..ca50ccd59b50 100644
> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
> @@ -3652,6 +3652,7 @@ struct ixgbe_hw {
>  	bool				allow_unsupported_sfp;
>  	bool				wol_enabled;
>  	bool				need_crosstalk_fix;
> +	bool				loopback_on;

please explain why are you introducing this flag

>  };
>  
>  struct ixgbe_info {
> 
> base-commit: 735c9ee9a374769b78c716de3c19a6c9440ede85
> -- 
> 2.34.1
>
Ma, Hao June 14, 2023, 10:02 a.m. UTC | #2 
> -----Original Message-----
> From: Fijalkowski, Maciej <maciej.fijalkowski@intel.com>
> Sent: Thursday, June 1, 2023 5:54 PM
> To: Magnus Karlsson <magnus.karlsson@gmail.com>
> Cc: Karlsson, Magnus <magnus.karlsson@intel.com>; intel-wired-lan@lists.osuosl.org; Nguyen, Anthony L <anthony.l.nguyen@intel.com>;
> Ma, Hao <hao.ma@intel.com>; netdev@vger.kernel.org
> Subject: Re: [PATCH iwl-next] ixgbe: allow toggling loopback mode via ndo_set_features callback
> 
> On Thu, Jun 01, 2023 at 09:46:21AM +0200, Magnus Karlsson wrote:
> > From: Hao Ma <hao.ma@intel.com>
> >
> > Add support for NETIF_F_LOOPBACK. This feature can be set via: $
> > ethtool -K eth0 loopback <on|off>. This sets the MAC Tx->Rx loopback
> > used by selftests/bpf/xskxceiver.
> >
> > Signed-off-by: Hao Ma <hao.ma@intel.com>
> > ---
> >  .../net/ethernet/intel/ixgbe/ixgbe_common.c   |  4 +-
> >  drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 73
> > +++++++++++++++++++  drivers/net/ethernet/intel/ixgbe/ixgbe_type.h |
> > 1 +
> >  3 files changed, 76 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
> > b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
> > index 878dd8dff528..b8998a56ad24 100644
> > --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
> > +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
> > @@ -3337,7 +3337,7 @@ s32 ixgbe_check_mac_link_generic(struct ixgbe_hw
> > *hw, ixgbe_link_speed *speed,
> >
> >  	if (link_up_wait_to_complete) {
> >  		for (i = 0; i < IXGBE_LINK_UP_TIME; i++) {
> > -			if (links_reg & IXGBE_LINKS_UP) {
> > +			if (links_reg & IXGBE_LINKS_UP || hw->loopback_on) {
> >  				*link_up = true;
> >  				break;
> >  			} else {
> > @@ -3347,7 +3347,7 @@ s32 ixgbe_check_mac_link_generic(struct ixgbe_hw *hw, ixgbe_link_speed *speed,
> >  			links_reg = IXGBE_READ_REG(hw, IXGBE_LINKS);
> >  		}
> >  	} else {
> > -		if (links_reg & IXGBE_LINKS_UP) {
> > +		if (links_reg & IXGBE_LINKS_UP || hw->loopback_on) {
> >  			if (crosstalk_fix_active) {
> >  				/* Check the link state again after a delay
> >  				 * to filter out spurious link up diff --git
> > a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> > b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> > index 5d83c887a3fc..70b34b7b5cb0 100644
> > --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> > +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> > @@ -8864,6 +8864,57 @@ netdev_tx_t ixgbe_xmit_frame_ring(struct sk_buff *skb,
> >  	return NETDEV_TX_OK;
> >  }
> >
> > +static int ixgbe_force_loopback(struct ixgbe_adapter *adapter, bool on)
> > +{	struct ixgbe_hw *hw = &adapter->hw;
> > +	u32 reg_data;
> > +
> > +	hw->loopback_on = on;
> > +	/* Setup MAC loopback */
> > +	reg_data = IXGBE_READ_REG(hw, IXGBE_HLREG0);
> > +	if (on)
> > +		reg_data |= IXGBE_HLREG0_LPBK;
> > +	else
> > +		reg_data &= ~IXGBE_HLREG0_LPBK;
> > +	IXGBE_WRITE_REG(hw, IXGBE_HLREG0, reg_data);
> > +
> > +	reg_data = IXGBE_READ_REG(hw, IXGBE_FCTRL);
> > +	if (on)
> > +		reg_data |= IXGBE_FCTRL_SBP | IXGBE_FCTRL_MPE;
> > +	else
> > +		reg_data &= ~(IXGBE_FCTRL_SBP | IXGBE_FCTRL_MPE);
> > +	reg_data &= ~(IXGBE_FCTRL_BAM);
> > +	IXGBE_WRITE_REG(hw, IXGBE_FCTRL, reg_data);
> > +
> > +	/* X540 and X550 needs to set the MACC.FLU bit to force link up */
> > +	switch (adapter->hw.mac.type) {
> > +	case ixgbe_mac_X540:
> > +	case ixgbe_mac_X550:
> > +	case ixgbe_mac_X550EM_x:
> > +	case ixgbe_mac_x550em_a:
> > +		reg_data = IXGBE_READ_REG(hw, IXGBE_MACC);
> > +		if (on)
> > +			reg_data |= IXGBE_MACC_FLU;
> > +		else
> > +			reg_data &= ~IXGBE_MACC_FLU;
> > +		IXGBE_WRITE_REG(hw, IXGBE_MACC, reg_data);
> > +		break;
> > +	default:
> > +		if (hw->mac.orig_autoc) {
> > +			if (on)
> > +				reg_data = hw->mac.orig_autoc | IXGBE_AUTOC_FLU;
> > +			else
> > +				reg_data = hw->mac.orig_autoc & ~IXGBE_AUTOC_FLU;
> > +			IXGBE_WRITE_REG(hw, IXGBE_AUTOC, reg_data);
> > +		} else {
> > +			return 10;
> > +		}
> > +	}
> > +
> > +	IXGBE_WRITE_FLUSH(hw);
> > +
> > +	return 0;
> > +}
> > +
> >  static netdev_tx_t __ixgbe_xmit_frame(struct sk_buff *skb,
> >  				      struct net_device *netdev,
> >  				      struct ixgbe_ring *ring)
> > @@ -9915,6 +9966,15 @@ static int ixgbe_set_features(struct net_device *netdev,
> >  	if (changed & NETIF_F_RXALL)
> >  		need_reset = true;
> >
> > +	if (changed & NETIF_F_LOOPBACK) {
> > +		if (features & NETIF_F_LOOPBACK) {
> > +			ixgbe_force_loopback(adapter, true);
> > +		} else {
> > +			ixgbe_force_loopback(adapter, false);
> > +			need_reset = true;
> > +			}
> 
> on ice we just do:
> 
> 	if (changed & NETIF_F_LOOPBACK)
> 		ret = ice_set_loopback(vsi, !!(features & NETIF_F_LOOPBACK));
> 
> don't you need to set need_reset to true as well when you are disabling loopback in order to clear appropriate bits from registers?
> 
ixgbe driver loopback enablement can interfere with NIC normal function configuration, so after test, a reset is needed and reconfigure NIC back to normal function.
> > +	}
> > +
> >  	netdev->features = features;
> >
> >  	if ((changed & NETIF_F_HW_L2FW_DOFFLOAD) && adapter->num_rx_pools >
> > 1) @@ -10286,6 +10346,17 @@ static int ixgbe_xdp_setup(struct net_device *dev, struct bpf_prog *prog)
> >  			/* Wait until ndo_xsk_wakeup completes. */
> >  			synchronize_rcu();
> >  		err = ixgbe_setup_tc(dev, adapter->hw_tcs);
> > +		if (adapter->hw.loopback_on) {
> > +			u32 reg_data;
> > +
> > +			reg_data = IXGBE_READ_REG(&adapter->hw, IXGBE_HLREG0);
> > +			reg_data |= IXGBE_HLREG0_LPBK;
> > +			IXGBE_WRITE_REG(&adapter->hw, IXGBE_HLREG0, reg_data);
> > +
> > +			reg_data = IXGBE_READ_REG(&adapter->hw, IXGBE_MACC);
> > +			reg_data |= IXGBE_MACC_FLU;
> > +			IXGBE_WRITE_REG(&adapter->hw, IXGBE_MACC, reg_data);
> 
> can you explain why do you need to set loopback bits again after they were set on ixgbe_force_loopback() ? are they not preserved after
> downing an interface?
> 
In ixgbe NIC XDP initialization process, the corresponding register will be reset.
> > +		}
> >
> >  		if (err)
> >  			return -EINVAL;
> > @@ -10969,6 +11040,8 @@ static int ixgbe_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
> >  	if (hw->mac.type >= ixgbe_mac_82599EB)
> >  		netdev->features |= NETIF_F_SCTP_CRC | NETIF_F_GSO_UDP_L4;
> >
> > +	netdev->features |= NETIF_F_LOOPBACK;
> > +
> >  #ifdef CONFIG_IXGBE_IPSEC
> >  #define IXGBE_ESP_FEATURES	(NETIF_F_HW_ESP | \
> >  				 NETIF_F_HW_ESP_TX_CSUM | \
> > diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
> > b/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
> > index 2b00db92b08f..ca50ccd59b50 100644
> > --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
> > +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
> > @@ -3652,6 +3652,7 @@ struct ixgbe_hw {
> >  	bool				allow_unsupported_sfp;
> >  	bool				wol_enabled;
> >  	bool				need_crosstalk_fix;
> > +	bool				loopback_on;
> 
> please explain why are you introducing this flag
> 
Please refer to the previous comment.
> >  };
> >
> >  struct ixgbe_info {
> >
> > base-commit: 735c9ee9a374769b78c716de3c19a6c9440ede85
> > --
> > 2.34.1
> >
Brett Creeley June 14, 2023, 7:12 p.m. UTC | #3 
On 6/1/2023 12:46 AM, Magnus Karlsson wrote:
> Caution: This message originated from an External Source. Use proper caution when opening attachments, clicking links, or responding.
> 
> 
> From: Hao Ma <hao.ma@intel.com>
> 
> Add support for NETIF_F_LOOPBACK. This feature can be set via: $
> ethtool -K eth0 loopback <on|off>. This sets the MAC Tx->Rx loopback
> used by selftests/bpf/xskxceiver.
> 
> Signed-off-by: Hao Ma <hao.ma@intel.com>
> ---
>   .../net/ethernet/intel/ixgbe/ixgbe_common.c   |  4 +-
>   drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 73 +++++++++++++++++++
>   drivers/net/ethernet/intel/ixgbe/ixgbe_type.h |  1 +
>   3 files changed, 76 insertions(+), 2 deletions(-)
> 

[...]

> @@ -10969,6 +11040,8 @@ static int ixgbe_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
>          if (hw->mac.type >= ixgbe_mac_82599EB)
>                  netdev->features |= NETIF_F_SCTP_CRC | NETIF_F_GSO_UDP_L4;
> 
> +       netdev->features |= NETIF_F_LOOPBACK;

This means NETIF_F_LOOPBACK is enabled by default. Was that the 
intention? It seems like NETIF_F_LOOPBACK should only be set for 
netdev->hw_features on probe. I didn't test this, so it would be worth 
double this patch functions as expected with this change.

> +
>   #ifdef CONFIG_IXGBE_IPSEC
>   #define IXGBE_ESP_FEATURES     (NETIF_F_HW_ESP | \
>                                   NETIF_F_HW_ESP_TX_CSUM | \
> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h b/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
> index 2b00db92b08f..ca50ccd59b50 100644
> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
> @@ -3652,6 +3652,7 @@ struct ixgbe_hw {
>          bool                            allow_unsupported_sfp;
>          bool                            wol_enabled;
>          bool                            need_crosstalk_fix;
> +       bool                            loopback_on;
>   };
> 
>   struct ixgbe_info {
> 
> base-commit: 735c9ee9a374769b78c716de3c19a6c9440ede85
> --
> 2.34.1
> 
>
diff mbox series

Patch

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
index 878dd8dff528..b8998a56ad24 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
@@ -3337,7 +3337,7 @@  s32 ixgbe_check_mac_link_generic(struct ixgbe_hw *hw, ixgbe_link_speed *speed,
 
 	if (link_up_wait_to_complete) {
 		for (i = 0; i < IXGBE_LINK_UP_TIME; i++) {
-			if (links_reg & IXGBE_LINKS_UP) {
+			if (links_reg & IXGBE_LINKS_UP || hw->loopback_on) {
 				*link_up = true;
 				break;
 			} else {
@@ -3347,7 +3347,7 @@  s32 ixgbe_check_mac_link_generic(struct ixgbe_hw *hw, ixgbe_link_speed *speed,
 			links_reg = IXGBE_READ_REG(hw, IXGBE_LINKS);
 		}
 	} else {
-		if (links_reg & IXGBE_LINKS_UP) {
+		if (links_reg & IXGBE_LINKS_UP || hw->loopback_on) {
 			if (crosstalk_fix_active) {
 				/* Check the link state again after a delay
 				 * to filter out spurious link up
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 5d83c887a3fc..70b34b7b5cb0 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -8864,6 +8864,57 @@  netdev_tx_t ixgbe_xmit_frame_ring(struct sk_buff *skb,
 	return NETDEV_TX_OK;
 }
 
+static int ixgbe_force_loopback(struct ixgbe_adapter *adapter, bool on)
+{	struct ixgbe_hw *hw = &adapter->hw;
+	u32 reg_data;
+
+	hw->loopback_on = on;
+	/* Setup MAC loopback */
+	reg_data = IXGBE_READ_REG(hw, IXGBE_HLREG0);
+	if (on)
+		reg_data |= IXGBE_HLREG0_LPBK;
+	else
+		reg_data &= ~IXGBE_HLREG0_LPBK;
+	IXGBE_WRITE_REG(hw, IXGBE_HLREG0, reg_data);
+
+	reg_data = IXGBE_READ_REG(hw, IXGBE_FCTRL);
+	if (on)
+		reg_data |= IXGBE_FCTRL_SBP | IXGBE_FCTRL_MPE;
+	else
+		reg_data &= ~(IXGBE_FCTRL_SBP | IXGBE_FCTRL_MPE);
+	reg_data &= ~(IXGBE_FCTRL_BAM);
+	IXGBE_WRITE_REG(hw, IXGBE_FCTRL, reg_data);
+
+	/* X540 and X550 needs to set the MACC.FLU bit to force link up */
+	switch (adapter->hw.mac.type) {
+	case ixgbe_mac_X540:
+	case ixgbe_mac_X550:
+	case ixgbe_mac_X550EM_x:
+	case ixgbe_mac_x550em_a:
+		reg_data = IXGBE_READ_REG(hw, IXGBE_MACC);
+		if (on)
+			reg_data |= IXGBE_MACC_FLU;
+		else
+			reg_data &= ~IXGBE_MACC_FLU;
+		IXGBE_WRITE_REG(hw, IXGBE_MACC, reg_data);
+		break;
+	default:
+		if (hw->mac.orig_autoc) {
+			if (on)
+				reg_data = hw->mac.orig_autoc | IXGBE_AUTOC_FLU;
+			else
+				reg_data = hw->mac.orig_autoc & ~IXGBE_AUTOC_FLU;
+			IXGBE_WRITE_REG(hw, IXGBE_AUTOC, reg_data);
+		} else {
+			return 10;
+		}
+	}
+
+	IXGBE_WRITE_FLUSH(hw);
+
+	return 0;
+}
+
 static netdev_tx_t __ixgbe_xmit_frame(struct sk_buff *skb,
 				      struct net_device *netdev,
 				      struct ixgbe_ring *ring)
@@ -9915,6 +9966,15 @@  static int ixgbe_set_features(struct net_device *netdev,
 	if (changed & NETIF_F_RXALL)
 		need_reset = true;
 
+	if (changed & NETIF_F_LOOPBACK) {
+		if (features & NETIF_F_LOOPBACK) {
+			ixgbe_force_loopback(adapter, true);
+		} else {
+			ixgbe_force_loopback(adapter, false);
+			need_reset = true;
+			}
+	}
+
 	netdev->features = features;
 
 	if ((changed & NETIF_F_HW_L2FW_DOFFLOAD) && adapter->num_rx_pools > 1)
@@ -10286,6 +10346,17 @@  static int ixgbe_xdp_setup(struct net_device *dev, struct bpf_prog *prog)
 			/* Wait until ndo_xsk_wakeup completes. */
 			synchronize_rcu();
 		err = ixgbe_setup_tc(dev, adapter->hw_tcs);
+		if (adapter->hw.loopback_on) {
+			u32 reg_data;
+
+			reg_data = IXGBE_READ_REG(&adapter->hw, IXGBE_HLREG0);
+			reg_data |= IXGBE_HLREG0_LPBK;
+			IXGBE_WRITE_REG(&adapter->hw, IXGBE_HLREG0, reg_data);
+
+			reg_data = IXGBE_READ_REG(&adapter->hw, IXGBE_MACC);
+			reg_data |= IXGBE_MACC_FLU;
+			IXGBE_WRITE_REG(&adapter->hw, IXGBE_MACC, reg_data);
+		}
 
 		if (err)
 			return -EINVAL;
@@ -10969,6 +11040,8 @@  static int ixgbe_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	if (hw->mac.type >= ixgbe_mac_82599EB)
 		netdev->features |= NETIF_F_SCTP_CRC | NETIF_F_GSO_UDP_L4;
 
+	netdev->features |= NETIF_F_LOOPBACK;
+
 #ifdef CONFIG_IXGBE_IPSEC
 #define IXGBE_ESP_FEATURES	(NETIF_F_HW_ESP | \
 				 NETIF_F_HW_ESP_TX_CSUM | \
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h b/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
index 2b00db92b08f..ca50ccd59b50 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
@@ -3652,6 +3652,7 @@  struct ixgbe_hw {
 	bool				allow_unsupported_sfp;
 	bool				wol_enabled;
 	bool				need_crosstalk_fix;
+	bool				loopback_on;
 };
 
 struct ixgbe_info {