When the PF negotiates TX PAUSE on the port it signals this to the VF via BIT(1) of the PF-to-VF link status mailbox message. The VF PMD must respond by setting RBMR_CM (BIT(4)) on all active RX rings so the MAC emits PAUSE frames on ingress pressure.
Add ENETC_RBMR_CM register definition, ENETC_LINK_TX_PAUSE bitmask, and tx_pause_active state flag. Add enetc4_vf_set_congestion_mode() to update all active RX rings and persist the state for rings started later. Hook it into both the interrupt and poll link-update paths, and apply the saved state in rx_queue_setup() and rx_queue_start(). RX PAUSE (honoring received PAUSE frames) is handled at the MAC level by the PF and requires no VF PMD changes. Signed-off-by: Gagandeep Singh <[email protected]> --- doc/guides/nics/features/enetc4.ini | 1 + doc/guides/rel_notes/release_26_11.rst | 1 + drivers/net/enetc/base/enetc_hw.h | 1 + drivers/net/enetc/enetc.h | 9 +++- drivers/net/enetc/enetc4_ethdev.c | 13 +++++- drivers/net/enetc/enetc4_vf.c | 59 ++++++++++++++++++++++++-- 6 files changed, 78 insertions(+), 6 deletions(-) diff --git a/doc/guides/nics/features/enetc4.ini b/doc/guides/nics/features/enetc4.ini index 01b0dc5b80..1f599dace7 100644 --- a/doc/guides/nics/features/enetc4.ini +++ b/doc/guides/nics/features/enetc4.ini @@ -14,6 +14,7 @@ Promiscuous mode = Y Allmulticast mode = Y Unicast MAC filter = Y VLAN filter = Y +Flow control = Y VLAN offload = Y RSS hash = Y Packet type parsing = Y diff --git a/doc/guides/rel_notes/release_26_11.rst b/doc/guides/rel_notes/release_26_11.rst index 5323f4fea3..d69888aafb 100644 --- a/doc/guides/rel_notes/release_26_11.rst +++ b/doc/guides/rel_notes/release_26_11.rst @@ -72,6 +72,7 @@ New Features * Added per-queue MSI-X Rx interrupt support for the ENETC4 VF. * Added SI-based port VLAN insertion (Tx) and removal (Rx) for ENETC4 PF and VF. * Updated ENETC4 VF link status reporting to use bitmask encoding. + * Added TX PAUSE support for the ENETC4 VF via RX congestion mode. Removed Items ------------- diff --git a/drivers/net/enetc/base/enetc_hw.h b/drivers/net/enetc/base/enetc_hw.h index 6e96562850..33d075fe59 100644 --- a/drivers/net/enetc/base/enetc_hw.h +++ b/drivers/net/enetc/base/enetc_hw.h @@ -51,6 +51,7 @@ enum enetc_bdr_type {TX, RX}; + (off)) /* RX BDR reg offsets */ #define ENETC_RBMR 0x0 /* RX BDR mode register*/ +#define ENETC_RBMR_CM BIT(4) /* congestion mode: assert congestion to emit TX PAUSE */ #define ENETC_RBMR_EN BIT(31) #define ENETC_BMR_RESET 0x0 /* BDR reset*/ diff --git a/drivers/net/enetc/enetc.h b/drivers/net/enetc/enetc.h index 40bad56341..8aaf8a7eb1 100644 --- a/drivers/net/enetc/enetc.h +++ b/drivers/net/enetc/enetc.h @@ -140,6 +140,10 @@ struct enetc_eth_hw { * for PF kernel versions before 6.18.37. Set via vf_link_legacy devarg. */ uint8_t vf_link_legacy; + /* 1 = TX PAUSE negotiated on port; VF RX rings must have RBMR_CM set. + * Updated from the PF-to-VF link status mailbox message (BIT(1)). + */ + uint8_t tx_pause_active; /* Baseline snapshot for VF stats reset (software delta approach). */ struct enetc4_vf_stats_saved vf_stats_saved; }; @@ -238,8 +242,11 @@ enum vlan_status { /* Link status bitmask in PF-to-VF mailbox notification. * Link up is encoded as the DOWN bit being clear. + * TX_PAUSE is set when the port has negotiated TX PAUSE; VF must enable + * congestion mode (ENETC_RBMR_CM) on its RX rings accordingly. */ -#define ENETC_LINK_DOWN (1u << 0) +#define ENETC_LINK_DOWN (1u << 0) +#define ENETC_LINK_TX_PAUSE (1u << 1) enum speed { ENETC_SPEED_UNKNOWN = 0x0, diff --git a/drivers/net/enetc/enetc4_ethdev.c b/drivers/net/enetc/enetc4_ethdev.c index ae40cc69e0..2355522515 100644 --- a/drivers/net/enetc/enetc4_ethdev.c +++ b/drivers/net/enetc/enetc4_ethdev.c @@ -712,8 +712,12 @@ enetc4_rx_queue_setup(struct rte_eth_dev *dev, } if (!rx_conf->rx_deferred_start) { - /* enable ring */ + /* Enable ring; apply congestion mode if TX PAUSE is already active. */ rx_enable |= ENETC_RBMR_EN; + if (adapter->hw.tx_pause_active) + rx_enable |= ENETC_RBMR_CM; + else + rx_enable &= ~(uint32_t)ENETC_RBMR_CM; enetc4_rxbdr_wr(&adapter->hw.hw, rx_ring->index, ENETC_RBMR, rx_enable); dev->data->rx_queue_state[rx_ring->index] = @@ -1089,7 +1093,12 @@ enetc4_rx_queue_start(struct rte_eth_dev *dev, uint16_t qidx) if (dev->data->rx_queue_state[qidx] == RTE_ETH_QUEUE_STATE_STOPPED) { rx_data = enetc4_rxbdr_rd(&priv->hw.hw, rx_ring->index, ENETC_RBMR); - rx_data = rx_data | ENETC_RBMR_EN; + rx_data |= ENETC_RBMR_EN; + /* Restore congestion mode if TX PAUSE is active. */ + if (priv->hw.tx_pause_active) + rx_data |= ENETC_RBMR_CM; + else + rx_data &= ~(uint32_t)ENETC_RBMR_CM; enetc4_rxbdr_wr(&priv->hw.hw, rx_ring->index, ENETC_RBMR, rx_data); dev->data->rx_queue_state[qidx] = RTE_ETH_QUEUE_STATE_STARTED; diff --git a/drivers/net/enetc/enetc4_vf.c b/drivers/net/enetc/enetc4_vf.c index 1b93835dd7..c68bc8521b 100644 --- a/drivers/net/enetc/enetc4_vf.c +++ b/drivers/net/enetc/enetc4_vf.c @@ -461,6 +461,37 @@ enetc4_decode_link_speed(uint8_t status, bool vf_link_legacy, } } +/* + * Set or clear ENETC_RBMR_CM (congestion mode) on all active VF RX rings. + * When set, the ring signals congestion to the MAC, causing it to emit TX + * PAUSE frames on ingress pressure. hw->tx_pause_active is updated so rings + * started later inherit the correct state. + */ +static void +enetc4_vf_set_congestion_mode(struct rte_eth_dev *eth_dev, bool enable) +{ + struct enetc_eth_hw *hw = + ENETC_DEV_PRIVATE_TO_HW(eth_dev->data->dev_private); + struct enetc_hw *enetc_hw = &hw->hw; + uint16_t nb_rx = eth_dev->data->nb_rx_queues; + uint16_t i; + uint32_t rbmr; + + hw->tx_pause_active = enable ? 1 : 0; + + for (i = 0; i < nb_rx; i++) { + rbmr = enetc4_rxbdr_rd(enetc_hw, i, ENETC_RBMR); + if (enable) + rbmr |= ENETC_RBMR_CM; + else + rbmr &= ~(uint32_t)ENETC_RBMR_CM; + enetc4_rxbdr_wr(enetc_hw, i, ENETC_RBMR, rbmr); + } + + ENETC_PMD_DEBUG("VF congestion mode %s on %u RX rings", + enable ? "enabled" : "disabled", nb_rx); +} + static void enetc4_process_psi_msg(struct rte_eth_dev *eth_dev, struct enetc_hw *enetc_hw) { @@ -468,6 +499,7 @@ enetc4_process_psi_msg(struct rte_eth_dev *eth_dev, struct enetc_hw *enetc_hw) ENETC_DEV_PRIVATE_TO_HW(eth_dev->data->dev_private); struct enetc_psi_reply_msg *msg; struct rte_eth_link link; + bool tx_pause; int ret = 0; msg = rte_zmalloc(NULL, sizeof(*msg), RTE_CACHE_LINE_SIZE); @@ -483,9 +515,24 @@ enetc4_process_psi_msg(struct rte_eth_dev *eth_dev, struct enetc_hw *enetc_hw) if (msg->status & ENETC_LINK_DOWN) { ENETC_PMD_DEBUG("Link is down"); link.link_status = RTE_ETH_LINK_DOWN; + /* Clear congestion mode on link-down so VF rings do not + * assert congestion while the port is offline. + */ + enetc4_vf_set_congestion_mode(eth_dev, false); } else { - ENETC_PMD_DEBUG("Link is up"); + /* BIT(1) is set when the port has negotiated TX PAUSE. + * Legacy PF does not set this bit so tx_pause stays false. + */ + tx_pause = !!(msg->status & ENETC_LINK_TX_PAUSE); + ENETC_PMD_DEBUG("Link is up, tx_pause=%d", tx_pause); link.link_status = RTE_ETH_LINK_UP; + + /* Apply congestion mode before raising the carrier so + * the VF rings are ready to emit PAUSE before traffic + * starts flowing. + */ + enetc4_vf_set_congestion_mode(eth_dev, tx_pause); + /* Re-query speed from PF so the cached value reflects * the current negotiated speed after link-up. */ @@ -1174,10 +1221,16 @@ enetc4_vf_link_update(struct rte_eth_dev *dev, int wait_to_complete __rte_unused } if (reply_msg->class_id == ENETC_CLASS_ID_LINK_STATUS) { - if (reply_msg->status & ENETC_LINK_DOWN) + if (reply_msg->status & ENETC_LINK_DOWN) { link.link_status = RTE_ETH_LINK_DOWN; - else + /* Link is down: disable congestion mode on all RX rings. */ + enetc4_vf_set_congestion_mode(dev, false); + } else { link.link_status = RTE_ETH_LINK_UP; + /* Restore congestion mode from the TX PAUSE bit. */ + enetc4_vf_set_congestion_mode(dev, + !!(reply_msg->status & ENETC_LINK_TX_PAUSE)); + } } else { ENETC_PMD_ERR("Wrong reply message"); return -1; -- 2.25.1
