RE: [PATCH 08/18] net/txgbe: fix link flow control registers for Amber-Lite

["Jiawen Wu" <jiawenwu@trustnetic.com>]

> -----Original Message-----
> From: Zaiyu Wang <zaiyuwang@trustnetic.com>
> Sent: Thursday, April 23, 2026 11:40 AM
> To: dev@dpdk.org
> Cc: Zaiyu Wang <zaiyuwang@trustnetic.com>; stable@dpdk.org; Jiawen Wu <jiawenwu@trustnetic.com>
> Subject: [PATCH 08/18] net/txgbe: fix link flow control registers for Amber-Lite
> 
> The flow control counter registers on AML NICs differ from those on SP
> NICs. Update the register offsets accordingly to ensure the counters
> work correctly.
> 
> Cc: stable@dpdk.org
> 
> Signed-off-by: Zaiyu Wang <zaiyuwang@trustnetic.com>
> ---
>  drivers/net/txgbe/base/txgbe_hw.c   |  5 +++++
>  drivers/net/txgbe/base/txgbe_regs.h |  2 ++
>  drivers/net/txgbe/txgbe_ethdev.c    | 10 ++++++++--
>  3 files changed, 15 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/txgbe/base/txgbe_hw.c b/drivers/net/txgbe/base/txgbe_hw.c
> index 0f3db3a1ad..52fead6171 100644
> --- a/drivers/net/txgbe/base/txgbe_hw.c
> +++ b/drivers/net/txgbe/base/txgbe_hw.c
> @@ -394,6 +394,11 @@ s32 txgbe_clear_hw_cntrs(struct txgbe_hw *hw)
>  	rd32(hw, TXGBE_PBTXLNKXON);
>  	rd32(hw, TXGBE_PBTXLNKXOFF);
> 
> +	if (hw->mac.type == txgbe_mac_aml || hw->mac.type == txgbe_mac_aml40) {
> +		wr32(hw, TXGBE_PBRXLNKXON_AML, 0);
> +		wr32(hw, TXGBE_PBRXLNKXOFF_AML, 0);
> +	}
> +
>  	/* DMA Stats */
>  	rd32(hw, TXGBE_DMARXPKT);
>  	rd32(hw, TXGBE_DMATXPKT);
> diff --git a/drivers/net/txgbe/base/txgbe_regs.h b/drivers/net/txgbe/base/txgbe_regs.h
> index 060757323a..de382601c9 100644
> --- a/drivers/net/txgbe/base/txgbe_regs.h
> +++ b/drivers/net/txgbe/base/txgbe_regs.h
> @@ -1085,6 +1085,8 @@ enum txgbe_5tuple_protocol {
>  #define TXGBE_PBRXDROP                    0x019068
>  #define TXGBE_PBRXLNKXOFF                 0x011988
>  #define TXGBE_PBRXLNKXON                  0x011E0C
> +#define TXGBE_PBRXLNKXOFF_AML             0x011F80
> +#define TXGBE_PBRXLNKXON_AML              0x011F84
>  #define TXGBE_PBRXUPXON(up)               (0x011E30 + (up) * 4)
>  #define TXGBE_PBRXUPXOFF(up)              (0x011E10 + (up) * 4)
> 
> diff --git a/drivers/net/txgbe/txgbe_ethdev.c b/drivers/net/txgbe/txgbe_ethdev.c
> index 414107d7a7..e3492c9cd7 100644
> --- a/drivers/net/txgbe/txgbe_ethdev.c
> +++ b/drivers/net/txgbe/txgbe_ethdev.c
> @@ -2331,8 +2331,14 @@ txgbe_read_stats_registers(struct txgbe_hw *hw,
>  		hw_stats->up[i].rx_up_dropped +=
>  				rd32(hw, TXGBE_PBRXMISS(i));
>  	}
> -	hw_stats->rx_xon_packets += rd32(hw, TXGBE_PBRXLNKXON);
> -	hw_stats->rx_xoff_packets += rd32(hw, TXGBE_PBRXLNKXOFF);
> +
> +	if (hw->mac.type == txgbe_mac_aml || hw->mac.type == txgbe_mac_aml40) {
> +		hw_stats->rx_xon_packets = rd32(hw, TXGBE_PBRXLNKXON_AML);
> +		hw_stats->rx_xoff_packets = rd32(hw, TXGBE_PBRXLNKXOFF_AML);

What happens to these counters after .stats_reset()?

> +	} else {
> +		hw_stats->rx_xon_packets += rd32(hw, TXGBE_PBRXLNKXON);
> +		hw_stats->rx_xoff_packets += rd32(hw, TXGBE_PBRXLNKXOFF);
> +	}
>  	hw_stats->tx_xon_packets += rd32(hw, TXGBE_PBTXLNKXON);
>  	hw_stats->tx_xoff_packets += rd32(hw, TXGBE_PBTXLNKXOFF);
> 
> --
> 2.21.0.windows.1
>