Re: [PATCH net-next v3 2/5] bnxt_en: Implement XDP RSS hash metadata extraction

[Andy Gospodarek <andrew.gospodarek@broadcom.com>]

On Fri, Mar 06, 2026 at 05:00:17PM -0600, Chris J Arges wrote:
> Add support for extracting RSS hash values and hash types from hardware
> completion descriptors in XDP programs for bnxt_en.
> 
> Add IP_TYPE definition for determining if completion is ipv4 or ipv6. In
> addition add ITYPE_ICMP flag for identifying ICMP completions.
> 
> Signed-off-by: Chris J Arges <carges@cloudflare.com>
> Reviewed-by: Joe Damato <joe@dama.to>
Reviewed-by: Andy Gospodarek <gospo@broadcom.com>

> ---
>  drivers/net/ethernet/broadcom/bnxt/bnxt.c     |  5 ++
>  drivers/net/ethernet/broadcom/bnxt/bnxt.h     |  2 +
>  drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c | 47 +++++++++++++++++++
>  drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h |  3 ++
>  4 files changed, 57 insertions(+)
> 
> diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> index ab73aad40593..c06033cf9f82 100644
> --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> @@ -15906,6 +15906,10 @@ static const struct net_device_ops bnxt_netdev_ops = {
>  	.ndo_hwtstamp_set	= bnxt_hwtstamp_set,
>  };
>  
> +static const struct xdp_metadata_ops bnxt_xdp_metadata_ops = {
> +	.xmo_rx_hash		= bnxt_xdp_rx_hash,
> +};
> +
>  static void bnxt_get_queue_stats_rx(struct net_device *dev, int i,
>  				    struct netdev_queue_stats_rx *stats)
>  {
> @@ -16790,6 +16794,7 @@ static int bnxt_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
>  		goto init_err_free;
>  
>  	dev->netdev_ops = &bnxt_netdev_ops;
> +	dev->xdp_metadata_ops = &bnxt_xdp_metadata_ops;
>  	dev->stat_ops = &bnxt_stat_ops;
>  	dev->watchdog_timeo = BNXT_TX_TIMEOUT;
>  	dev->ethtool_ops = &bnxt_ethtool_ops;
> diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
> index 90fa3e93c8d6..34bb98709f2b 100644
> --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
> +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
> @@ -232,6 +232,7 @@ struct rx_cmp {
>  	 #define RX_CMP_FLAGS_ITYPE_UDP				 (3 << 12)
>  	 #define RX_CMP_FLAGS_ITYPE_FCOE			 (4 << 12)
>  	 #define RX_CMP_FLAGS_ITYPE_ROCE			 (5 << 12)
> +	 #define RX_CMP_FLAGS_ITYPE_ICMP			 (7 << 12)
>  	 #define RX_CMP_FLAGS_ITYPE_PTP_WO_TS			 (8 << 12)
>  	 #define RX_CMP_FLAGS_ITYPE_PTP_W_TS			 (9 << 12)
>  	#define RX_CMP_LEN					(0xffff << 16)
> @@ -311,6 +312,7 @@ struct rx_cmp_ext {
>  	#define RX_CMP_FLAGS2_T_IP_CS_CALC			(0x1 << 2)
>  	#define RX_CMP_FLAGS2_T_L4_CS_CALC			(0x1 << 3)
>  	#define RX_CMP_FLAGS2_META_FORMAT_VLAN			(0x1 << 4)
> +	#define RX_CMP_FLAGS2_IP_TYPE				(0x1 << 8)
>  	__le32 rx_cmp_meta_data;
>  	#define RX_CMP_FLAGS2_METADATA_TCI_MASK			0xffff
>  	#define RX_CMP_FLAGS2_METADATA_VID_MASK			0xfff
> diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
> index 85cbeb35681c..1f920464b426 100644
> --- a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
> +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
> @@ -472,3 +472,50 @@ bnxt_xdp_build_skb(struct bnxt *bp, struct sk_buff *skb, u8 num_frags,
>  				  xdp_buff_get_skb_flags(xdp));
>  	return skb;
>  }
> +
> +int bnxt_xdp_rx_hash(const struct xdp_md *ctx, u32 *hash,
> +		     enum xdp_rss_hash_type *rss_type)
> +{
> +	const struct bnxt_xdp_buff *xdp = (void *)ctx;
> +	const struct rx_cmp_ext *rxcmp1 = xdp->rxcmp1;
> +	const struct rx_cmp *rxcmp = xdp->rxcmp;
> +	enum xdp_rss_hash_type hash_type = 0;
> +	u32 itypes;
> +
> +	if (!rxcmp || !RX_CMP_HASH_VALID(rxcmp))
> +		return -ENODATA;
> +
> +	*hash = le32_to_cpu(rxcmp->rx_cmp_rss_hash);
> +
> +	if (!rxcmp1) {
> +		*rss_type = XDP_RSS_TYPE_L2;
> +		return 0;
> +	}
> +
> +	if (xdp->cmp_type == CMP_TYPE_RX_L2_CMP) {
> +		itypes = RX_CMP_ITYPES(rxcmp);
> +		if (rxcmp1->rx_cmp_flags2 &
> +		    cpu_to_le32(RX_CMP_FLAGS2_IP_TYPE)) {
> +			hash_type |= XDP_RSS_TYPE_L3_IPV6;
> +		} else {
> +			hash_type |= XDP_RSS_TYPE_L3_IPV4;
> +		}
> +
> +		switch (itypes) {
> +		case RX_CMP_FLAGS_ITYPE_TCP:
> +			hash_type |= XDP_RSS_L4 | XDP_RSS_L4_TCP;
> +			break;
> +		case RX_CMP_FLAGS_ITYPE_UDP:
> +			hash_type |= XDP_RSS_L4 | XDP_RSS_L4_UDP;
> +			break;
> +		case RX_CMP_FLAGS_ITYPE_ICMP:
> +			hash_type |= XDP_RSS_L4 | XDP_RSS_L4_ICMP;
> +			break;
> +		default:
> +			break;
> +		}
> +	}
> +
> +	*rss_type = hash_type;
> +	return 0;
> +}
> diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h
> index 8c66698bde11..fb4f9143929f 100644
> --- a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h
> +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h
> @@ -41,4 +41,7 @@ void bnxt_xdp_buff_frags_free(struct bnxt_rx_ring_info *rxr,
>  struct sk_buff *bnxt_xdp_build_skb(struct bnxt *bp, struct sk_buff *skb,
>  				   u8 num_frags, struct bnxt_rx_ring_info *rxr,
>  				   struct xdp_buff *xdp);
> +int bnxt_xdp_rx_hash(const struct xdp_md *ctx, u32 *hash,
> +		     enum xdp_rss_hash_type *rss_type);
> +
>  #endif