> -----Original Message-----
> From: Takashi Kozu <[email protected]>
> Sent: Tuesday, January 20, 2026 10:35 AM
> To: Nguyen, Anthony L <[email protected]>
> Cc: Kitszel, Przemyslaw <[email protected]>;
> [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]; Loktionov, Aleksandr
> <[email protected]>; [email protected]; Kwapulinski,
> Piotr <[email protected]>; [email protected]; Takashi Kozu
> <[email protected]>
> Subject: [PATCH iwl-next v4 1/3] igb: prepare for RSS key get/set
> support
>
> Store the RSS key inside struct igb_adapter and introduce the
> igb_write_rss_key() helper function. This allows the driver to program
> the E1000 registers using a persistent RSS key, instead of using a
> stack-local buffer in igb_setup_mrqc().
>
> Signed-off-by: Takashi Kozu <[email protected]>
> ---
> drivers/net/ethernet/intel/igb/igb.h | 3 +++
> drivers/net/ethernet/intel/igb/igb_ethtool.c | 21
> ++++++++++++++++++++
> drivers/net/ethernet/intel/igb/igb_main.c | 8 ++++----
> 3 files changed, 28 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/net/ethernet/intel/igb/igb.h
> b/drivers/net/ethernet/intel/igb/igb.h
> index 0fff1df81b7b..8c9b02058cec 100644
> --- a/drivers/net/ethernet/intel/igb/igb.h
> +++ b/drivers/net/ethernet/intel/igb/igb.h
> @@ -495,6 +495,7 @@ struct hwmon_buff {
> #define IGB_N_PEROUT 2
> #define IGB_N_SDP 4
> #define IGB_RETA_SIZE 128
> +#define IGB_RSS_KEY_SIZE 40
>
> enum igb_filter_match_flags {
> IGB_FILTER_FLAG_ETHER_TYPE = 0x1,
> @@ -655,6 +656,7 @@ struct igb_adapter {
> struct i2c_client *i2c_client;
> u32 rss_indir_tbl_init;
> u8 rss_indir_tbl[IGB_RETA_SIZE];
> + u8 rss_key[IGB_RSS_KEY_SIZE];
>
> unsigned long link_check_timeout;
> int copper_tries;
> @@ -735,6 +737,7 @@ void igb_down(struct igb_adapter *); void
> igb_reinit_locked(struct igb_adapter *); void igb_reset(struct
> igb_adapter *); int igb_reinit_queues(struct igb_adapter *);
> +void igb_write_rss_key(struct igb_adapter *adapter);
> void igb_write_rss_indir_tbl(struct igb_adapter *); int
> igb_set_spd_dplx(struct igb_adapter *, u32, u8); int
> igb_setup_tx_resources(struct igb_ring *); diff --git
> a/drivers/net/ethernet/intel/igb/igb_ethtool.c
> b/drivers/net/ethernet/intel/igb/igb_ethtool.c
> index b507576b28b2..a93069b761a6 100644
> --- a/drivers/net/ethernet/intel/igb/igb_ethtool.c
> +++ b/drivers/net/ethernet/intel/igb/igb_ethtool.c
> @@ -3019,6 +3019,27 @@ static int igb_set_rxnfc(struct net_device
> *dev, struct ethtool_rxnfc *cmd)
> return ret;
> }
>
> +/**
> + * igb_write_rss_key - Program the RSS key into device registers
> + * @adapter: board private structure
> + *
> + * Write the RSS key stored in adapter->rss_key to the E1000 hardware
> registers.
> + * Each 32-bit chunk of the key is read using get_unaligned_le32()
> and
> +written
> + * to the appropriate register.
> + */
> +void igb_write_rss_key(struct igb_adapter *adapter) {
> + struct e1000_hw *hw = &adapter->hw;
> +
> + ASSERT_RTNL();
> +
> + for (int i = 0; i < IGB_RSS_KEY_SIZE / 4; i++) {
> + u32 val = get_unaligned_le32(&adapter->rss_key[i * 4]);
> +
> + wr32(E1000_RSSRK(i), val);
> + }
> +}
> +
> static int igb_get_eee(struct net_device *netdev, struct ethtool_keee
> *edata) {
> struct igb_adapter *adapter = netdev_priv(netdev); diff --git
> a/drivers/net/ethernet/intel/igb/igb_main.c
> b/drivers/net/ethernet/intel/igb/igb_main.c
> index dbea37269d2c..c703011b19ec 100644
> --- a/drivers/net/ethernet/intel/igb/igb_main.c
> +++ b/drivers/net/ethernet/intel/igb/igb_main.c
> @@ -4050,6 +4050,9 @@ static int igb_sw_init(struct igb_adapter
> *adapter)
>
> pci_read_config_word(pdev, PCI_COMMAND, &hw->bus.pci_cmd_word);
>
> + /* init RSS key */
> + netdev_rss_key_fill(adapter->rss_key, sizeof(adapter-
> >rss_key));
> +
> /* set default ring sizes */
> adapter->tx_ring_count = IGB_DEFAULT_TXD;
> adapter->rx_ring_count = IGB_DEFAULT_RXD; @@ -4525,11 +4528,8
> @@ static void igb_setup_mrqc(struct igb_adapter *adapter)
> struct e1000_hw *hw = &adapter->hw;
> u32 mrqc, rxcsum;
> u32 j, num_rx_queues;
> - u32 rss_key[10];
>
> - netdev_rss_key_fill(rss_key, sizeof(rss_key));
> - for (j = 0; j < 10; j++)
> - wr32(E1000_RSSRK(j), rss_key[j]);
> + igb_write_rss_key(adapter);
>
> num_rx_queues = adapter->rss_queues;
>
> --
> 2.52.0
Reviewed-by: Aleksandr Loktionov <[email protected]>
