Re: [dpdk-dev] [PATCH] net/ixgbe: add support of loopback for X540/X550

["Zhao1, Wei" <wei.zhao1@intel.com>]

> -----Original Message-----
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Julien Meunier
> Sent: Thursday, January 3, 2019 12:01 AM
> To: Ananyev, Konstantin <konstantin.ananyev@intel.com>; Lu, Wenzhuo
> <wenzhuo.lu@intel.com>
> Cc: dev@dpdk.org
> Subject: [dpdk-dev] [PATCH] net/ixgbe: add support of loopback for
> X540/X550
> 
> Loopback mode is also supported on X540 and X550 NICs, according to their
> datasheet (section 15.2). The way to set it up is a little different of the 82599.
> 
> Signed-off-by: Julien Meunier <julien.meunier@nokia.com>
> ---
>  drivers/net/ixgbe/ixgbe_ethdev.c | 10 ++++++---
> drivers/net/ixgbe/ixgbe_ethdev.h |  5 ++---
>  drivers/net/ixgbe/ixgbe_rxtx.c   | 47
> ++++++++++++++++++++++++++++++++++------
>  3 files changed, 49 insertions(+), 13 deletions(-)
> 
> diff --git a/drivers/net/ixgbe/ixgbe_ethdev.c
> b/drivers/net/ixgbe/ixgbe_ethdev.c
> index 7493110..7eb3303 100644
> --- a/drivers/net/ixgbe/ixgbe_ethdev.c
> +++ b/drivers/net/ixgbe/ixgbe_ethdev.c
> @@ -2652,9 +2652,13 @@ ixgbe_dev_start(struct rte_eth_dev *dev)
>  		goto error;
>  	}
> 
> -	/* Skip link setup if loopback mode is enabled for 82599. */
> -	if (hw->mac.type == ixgbe_mac_82599EB &&
> -			dev->data->dev_conf.lpbk_mode ==
> IXGBE_LPBK_82599_TX_RX)
> +	/* Skip link setup if loopback mode is enabled. */
> +	if ((hw->mac.type == ixgbe_mac_82599EB ||
> +	     hw->mac.type == ixgbe_mac_X540 ||
> +	     hw->mac.type == ixgbe_mac_X550 ||
> +	     hw->mac.type == ixgbe_mac_X550EM_x ||
> +	     hw->mac.type == ixgbe_mac_X550EM_a) &&
> +			dev->data->dev_conf.lpbk_mode ==
> IXGBE_LPBK_TX_RX)
>  		goto skip_link_setup;
> 
>  	if (ixgbe_is_sfp(hw) && hw->phy.multispeed_fiber) { diff --git
> a/drivers/net/ixgbe/ixgbe_ethdev.h b/drivers/net/ixgbe/ixgbe_ethdev.h
> index 565c69c..c60a697 100644
> --- a/drivers/net/ixgbe/ixgbe_ethdev.h
> +++ b/drivers/net/ixgbe/ixgbe_ethdev.h
> @@ -65,9 +65,8 @@
>  #define IXGBE_QUEUE_ITR_INTERVAL_DEFAULT	500 /* 500us */
> 
>  /* Loopback operation modes */
> -/* 82599 specific loopback operation types */
> -#define IXGBE_LPBK_82599_NONE   0x0 /* Default value. Loopback is
> disabled. */
> -#define IXGBE_LPBK_82599_TX_RX  0x1 /* Tx->Rx loopback operation is
> enabled. */
> +#define IXGBE_LPBK_NONE   0x0 /* Default value. Loopback is disabled. */
> +#define IXGBE_LPBK_TX_RX  0x1 /* Tx->Rx loopback operation is enabled.
> +*/
> 
>  #define IXGBE_MAX_JUMBO_FRAME_SIZE      0x2600 /* Maximum Jumbo
> frame size. */
> 
> diff --git a/drivers/net/ixgbe/ixgbe_rxtx.c b/drivers/net/ixgbe/ixgbe_rxtx.c
> index 9a79d18..0ef7fdf 100644
> --- a/drivers/net/ixgbe/ixgbe_rxtx.c
> +++ b/drivers/net/ixgbe/ixgbe_rxtx.c
> @@ -4879,10 +4879,14 @@ ixgbe_dev_rx_init(struct rte_eth_dev *dev)
>  		hlreg0 &= ~IXGBE_HLREG0_JUMBOEN;
> 
>  	/*
> -	 * If loopback mode is configured for 82599, set LPBK bit.
> +	 * If loopback mode is configured, set LPBK bit.
>  	 */
> -	if (hw->mac.type == ixgbe_mac_82599EB &&
> -			dev->data->dev_conf.lpbk_mode ==
> IXGBE_LPBK_82599_TX_RX)
> +	if ((hw->mac.type == ixgbe_mac_82599EB ||
> +	     hw->mac.type == ixgbe_mac_X540 ||
> +	     hw->mac.type == ixgbe_mac_X550 ||
> +	     hw->mac.type == ixgbe_mac_X550EM_x ||
> +	     hw->mac.type == ixgbe_mac_X550EM_a) &&
> +			dev->data->dev_conf.lpbk_mode ==
> IXGBE_LPBK_TX_RX)
>  		hlreg0 |= IXGBE_HLREG0_LPBK;
>  	else
>  		hlreg0 &= ~IXGBE_HLREG0_LPBK;
> @@ -5088,6 +5092,29 @@ ixgbe_setup_loopback_link_82599(struct
> ixgbe_hw *hw)
>  	msec_delay(50);
>  }
> 
> +/*
> + * Set up link loopback for X540 / X550 mode Tx->Rx.
> + */
> +static inline void __attribute__((cold))
> +ixgbe_setup_loopback_link_x540_x550(struct ixgbe_hw *hw) {
> +	uint32_t macc;
> +	PMD_INIT_FUNC_TRACE();
> +
> +	/* datasheet 15.2.1: MACC.FLU = 1 (force link up) */
> +	macc = IXGBE_READ_REG(hw, IXGBE_MACC);
> +	macc |= IXGBE_MACC_FLU;
> +	IXGBE_WRITE_REG(hw, IXGBE_MACC, macc);
> +
> +	/* Restart link */
> +	IXGBE_WRITE_REG(hw,
> +			IXGBE_AUTOC,
> +			IXGBE_AUTOC_LMS_10G_LINK_NO_AN |
> IXGBE_AUTOC_FLU);
> +
> +	hw->mac.ops.release_swfw_sync(hw, IXGBE_GSSR_MAC_CSR_SM);
> +	msec_delay(50);
> +}
> +
> 
>  /*
>   * Start Transmit and Receive Units.
> @@ -5148,10 +5175,16 @@ ixgbe_dev_rxtx_start(struct rte_eth_dev *dev)
>  	rxctrl |= IXGBE_RXCTRL_RXEN;
>  	hw->mac.ops.enable_rx_dma(hw, rxctrl);
> 
> -	/* If loopback mode is enabled for 82599, set up the link accordingly
> */
> -	if (hw->mac.type == ixgbe_mac_82599EB &&
> -			dev->data->dev_conf.lpbk_mode ==
> IXGBE_LPBK_82599_TX_RX)
> -		ixgbe_setup_loopback_link_82599(hw);
> +	/* If loopback mode is enabled, set up the link accordingly */
> +	if (dev->data->dev_conf.lpbk_mode == IXGBE_LPBK_TX_RX) {
> +		if (hw->mac.type == ixgbe_mac_82599EB)
> +			ixgbe_setup_loopback_link_82599(hw);
> +		else if (hw->mac.type == ixgbe_mac_X540 ||
> +		     hw->mac.type == ixgbe_mac_X550 ||
> +		     hw->mac.type == ixgbe_mac_X550EM_x ||
> +		     hw->mac.type == ixgbe_mac_X550EM_a)
> +			ixgbe_setup_loopback_link_x540_x550(hw);
		Else
			Return -1;

SHOULD we add some branch here? 
In case some other NIC with configuration for tx->rx loop but pmd code do not support.

> +	}

> 
>  #ifdef RTE_LIBRTE_SECURITY
>  	if ((dev->data->dev_conf.rxmode.offloads &
> --
> 2.10.2