From mboxrd@z Thu Jan  1 00:00:00 1970
From: =?UTF-8?Q?Martin_Dra=c5=a1ar?= <drasar@ics.muni.cz>
Subject: Broken RSS hash computation on Intel 82574L
Date: Mon, 31 Aug 2015 14:15:31 +0200
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Hi,

I am using RSS to get identical hash for both directions of a flow.
Everything is working as it should with the Intel 82599ES, but when I
run the same code with the Intel 82574L, then the hash is not calculated
correctly and returns 0 as a hash value for all flows.

I could use the Toeplitz hash implementation from 2.1.0, but I would
rather do it in hardware, because according to specification, 82574L can
do RSS in hardware.

Any ideas what might be wrong?

Thanks in advance,
Martin

conf:
#define RSS_HASH_KEY_LENGTH 40
static uint8_t hash_key[RSS_HASH_KEY_LENGTH] =3D {
        0x6D, 0x5A, 0x6D, 0x5A, 0x6D, 0x5A, 0x6D, 0x5A,
        0x6D, 0x5A, 0x6D, 0x5A, 0x6D, 0x5A, 0x6D, 0x5A,
        0x6D, 0x5A, 0x6D, 0x5A, 0x6D, 0x5A, 0x6D, 0x5A,
        0x6D, 0x5A, 0x6D, 0x5A, 0x6D, 0x5A, 0x6D, 0x5A,
        0x6D, 0x5A, 0x6D, 0x5A, 0x6D, 0x5A, 0x6D, 0x5A };

static const struct rte_eth_conf port_conf =3D {
  .link_speed  =3D 0,
  .link_duplex =3D 0,
  .rxmode =3D {
    .mq_mode        =3D ETH_RSS,
    .max_rx_pkt_len =3D 0,
    .split_hdr_size =3D 0,
    .header_split   =3D 0,
    .hw_ip_checksum =3D 0,
    .hw_vlan_filter =3D 0,
    .hw_vlan_strip  =3D 0,
    .hw_vlan_extend =3D 0,
    .jumbo_frame    =3D 0,
    .hw_strip_crc   =3D 0,
  },
  .txmode =3D {
    .mq_mode =3D ETH_DCB_NONE,
  },
  .lpbk_mode =3D 0,
  .rx_adv_conf =3D {
    .rss_conf =3D {
      .rss_key     =3D hash_key,
      .rss_key_len =3D RSS_HASH_KEY_LENGTH,
      .rss_hf      =3D ETH_RSS_PROTO_MASK,
      },
    },
};