iavf: add support for negotiating flexible RXDID format

Enable support for VIRTCHNL_VF_OFFLOAD_RX_FLEX_DESC, to enable the VF
driver the ability to determine what Rx descriptor formats are
available. This requires sending an additional message during
initialization and reset, the VIRTCHNL_OP_GET_SUPPORTED_RXDIDS. This
operation requests the supported Rx descriptor IDs available from the
PF.

This is treated the same way that VLAN V2 capabilities are handled. Add
a new set of extended capability flags, used to process send and receipt
of the VIRTCHNL_OP_GET_SUPPORTED_RXDIDS message.

This ensures we finish negotiating for the supported descriptor formats
prior to beginning configuration of receive queues.

This change stores the supported format bitmap into the iavf_adapter
structure. Additionally, if VIRTCHNL_VF_OFFLOAD_RX_FLEX_DESC is enabled
by the PF, we need to make sure that the Rx queue configuration
specifies the format.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Tested-by: Rafal Romanowski <rafal.romanowski@intel.com>
Co-developed-by: Mateusz Polchlopek <mateusz.polchlopek@intel.com>
Signed-off-by: Mateusz Polchlopek <mateusz.polchlopek@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

Author: jacob-keller

drivers/net/ethernet/intel/iavf/iavf.h

@@ -271,6 +271,7 @@ struct iavf_adapter {
 	/* Lock to protect accesses to MAC and VLAN lists */
 	spinlock_t mac_vlan_list_lock;
 	char misc_vector_name[IFNAMSIZ + 9];
+	u8 rxdid;
 	int num_active_queues;
 	int num_req_queues;
 
@@ -343,6 +344,14 @@ struct iavf_adapter {
 #define IAVF_FLAG_AQ_CONFIGURE_QUEUES_BW		BIT_ULL(39)
 #define IAVF_FLAG_AQ_CFG_QUEUES_QUANTA_SIZE		BIT_ULL(40)
 #define IAVF_FLAG_AQ_GET_QOS_CAPS			BIT_ULL(41)
+#define IAVF_FLAG_AQ_GET_SUPPORTED_RXDIDS		BIT_ULL(42)
+
+	/* AQ messages that must be sent after IAVF_FLAG_AQ_GET_CONFIG, in
+	 * order to negotiated extended capabilities.
+	 */
+#define IAVF_FLAG_AQ_EXTENDED_CAPS			\
+	(IAVF_FLAG_AQ_GET_OFFLOAD_VLAN_V2_CAPS |	\
+	 IAVF_FLAG_AQ_GET_SUPPORTED_RXDIDS)
 
 	/* flags for processing extended capability messages during
 	 * __IAVF_INIT_EXTENDED_CAPS. Each capability exchange requires
@@ -354,10 +363,14 @@ struct iavf_adapter {
 	u64 extended_caps;
 #define IAVF_EXTENDED_CAP_SEND_VLAN_V2			BIT_ULL(0)
 #define IAVF_EXTENDED_CAP_RECV_VLAN_V2			BIT_ULL(1)
+#define IAVF_EXTENDED_CAP_SEND_RXDID			BIT_ULL(2)
+#define IAVF_EXTENDED_CAP_RECV_RXDID			BIT_ULL(3)
 
 #define IAVF_EXTENDED_CAPS				\
 	(IAVF_EXTENDED_CAP_SEND_VLAN_V2 |		\
-	 IAVF_EXTENDED_CAP_RECV_VLAN_V2)
+	 IAVF_EXTENDED_CAP_RECV_VLAN_V2 |		\
+	 IAVF_EXTENDED_CAP_SEND_RXDID |			\
+	 IAVF_EXTENDED_CAP_RECV_RXDID)
 
 	/* Lock to prevent possible clobbering of
 	 * current_netdev_promisc_flags
@@ -417,12 +430,15 @@ struct iavf_adapter {
 			     VIRTCHNL_VF_OFFLOAD_ADV_RSS_PF)
 #define QOS_ALLOWED(_a) ((_a)->vf_res->vf_cap_flags & \
 			 VIRTCHNL_VF_OFFLOAD_QOS)
+#define IAVF_RXDID_ALLOWED(a)						\
+	((a)->vf_res->vf_cap_flags & VIRTCHNL_VF_OFFLOAD_RX_FLEX_DESC)
 	struct virtchnl_vf_resource *vf_res; /* incl. all VSIs */
 	struct virtchnl_vsi_resource *vsi_res; /* our LAN VSI */
 	struct virtchnl_version_info pf_version;
 #define PF_IS_V11(_a) (((_a)->pf_version.major == 1) && \
 		       ((_a)->pf_version.minor == 1))
 	struct virtchnl_vlan_caps vlan_v2_caps;
+	u64 supp_rxdids;
 	u16 msg_enable;
 	struct iavf_eth_stats current_stats;
 	struct virtchnl_qos_cap_list *qos_caps;
@@ -555,6 +571,8 @@ int iavf_send_vf_config_msg(struct iavf_adapter *adapter);
 int iavf_get_vf_config(struct iavf_adapter *adapter);
 int iavf_get_vf_vlan_v2_caps(struct iavf_adapter *adapter);
 int iavf_send_vf_offload_vlan_v2_msg(struct iavf_adapter *adapter);
+int iavf_send_vf_supported_rxdids_msg(struct iavf_adapter *adapter);
+int iavf_get_vf_supported_rxdids(struct iavf_adapter *adapter);
 void iavf_set_queue_vlan_tag_loc(struct iavf_adapter *adapter);
 u16 iavf_get_num_vlans_added(struct iavf_adapter *adapter);
 void iavf_irq_enable(struct iavf_adapter *adapter, bool flush);

drivers/net/ethernet/intel/iavf/iavf_main.c

@@ -709,6 +709,38 @@ static void iavf_configure_tx(struct iavf_adapter *adapter)
 		adapter->tx_rings[i].tail = hw->hw_addr + IAVF_QTX_TAIL1(i);
 }
 
+/**
+ * iavf_select_rx_desc_format - Select Rx descriptor format
+ * @adapter: adapter private structure
+ *
+ * Select what Rx descriptor format based on availability and enabled
+ * features.
+ *
+ * Return: the desired RXDID to select for a given Rx queue, as defined by
+ *         enum virtchnl_rxdid_format.
+ */
+static u8 iavf_select_rx_desc_format(const struct iavf_adapter *adapter)
+{
+	u64 rxdids = adapter->supp_rxdids;
+
+	/* If we did not negotiate VIRTCHNL_VF_OFFLOAD_RX_FLEX_DESC, we must
+	 * stick with the default value of the legacy 32 byte format.
+	 */
+	if (!IAVF_RXDID_ALLOWED(adapter))
+		return VIRTCHNL_RXDID_1_32B_BASE;
+
+	/* Warn if the PF does not list support for the default legacy
+	 * descriptor format. This shouldn't happen, as this is the format
+	 * used if VIRTCHNL_VF_OFFLOAD_RX_FLEX_DESC is not supported. It is
+	 * likely caused by a bug in the PF implementation failing to indicate
+	 * support for the format.
+	 */
+	if (!(rxdids & VIRTCHNL_RXDID_1_32B_BASE_M))
+		netdev_warn(adapter->netdev, "PF does not list support for default Rx descriptor format\n");
+
+	return VIRTCHNL_RXDID_1_32B_BASE;
+}
+
 /**
  * iavf_configure_rx - Configure Receive Unit after Reset
  * @adapter: board private structure
@@ -719,8 +751,12 @@ static void iavf_configure_rx(struct iavf_adapter *adapter)
 {
 	struct iavf_hw *hw = &adapter->hw;
 
-	for (u32 i = 0; i < adapter->num_active_queues; i++)
+	adapter->rxdid = iavf_select_rx_desc_format(adapter);
+
+	for (u32 i = 0; i < adapter->num_active_queues; i++) {
 		adapter->rx_rings[i].tail = hw->hw_addr + IAVF_QRX_TAIL1(i);
+		adapter->rx_rings[i].rxdid = adapter->rxdid;
+	}
 }
 
 /**
@@ -2071,6 +2107,8 @@ static int iavf_process_aq_command(struct iavf_adapter *adapter)
 		return iavf_send_vf_config_msg(adapter);
 	if (adapter->aq_required & IAVF_FLAG_AQ_GET_OFFLOAD_VLAN_V2_CAPS)
 		return iavf_send_vf_offload_vlan_v2_msg(adapter);
+	if (adapter->aq_required & IAVF_FLAG_AQ_GET_SUPPORTED_RXDIDS)
+		return iavf_send_vf_supported_rxdids_msg(adapter);
 	if (adapter->aq_required & IAVF_FLAG_AQ_DISABLE_QUEUES) {
 		iavf_disable_queues(adapter);
 		return 0;
@@ -2599,6 +2637,63 @@ static void iavf_init_recv_offload_vlan_v2_caps(struct iavf_adapter *adapter)
 	iavf_change_state(adapter, __IAVF_INIT_FAILED);
 }
 
+/**
+ * iavf_init_send_supported_rxdids - part of querying for supported RXDID
+ * formats
+ * @adapter: board private structure
+ *
+ * Function processes send of the request for supported RXDIDs to the PF.
+ * Must clear IAVF_EXTENDED_CAP_RECV_RXDID if the message is not sent, e.g.
+ * due to the PF not negotiating VIRTCHNL_VF_OFFLOAD_RX_FLEX_DESC.
+ */
+static void iavf_init_send_supported_rxdids(struct iavf_adapter *adapter)
+{
+	int ret;
+
+	ret = iavf_send_vf_supported_rxdids_msg(adapter);
+	if (ret == -EOPNOTSUPP) {
+		/* PF does not support VIRTCHNL_VF_OFFLOAD_RX_FLEX_DESC. In this
+		 * case, we did not send the capability exchange message and
+		 * do not expect a response.
+		 */
+		adapter->extended_caps &= ~IAVF_EXTENDED_CAP_RECV_RXDID;
+	}
+
+	/* We sent the message, so move on to the next step */
+	adapter->extended_caps &= ~IAVF_EXTENDED_CAP_SEND_RXDID;
+}
+
+/**
+ * iavf_init_recv_supported_rxdids - part of querying for supported RXDID
+ * formats
+ * @adapter: board private structure
+ *
+ * Function processes receipt of the supported RXDIDs message from the PF.
+ **/
+static void iavf_init_recv_supported_rxdids(struct iavf_adapter *adapter)
+{
+	int ret;
+
+	memset(&adapter->supp_rxdids, 0, sizeof(adapter->supp_rxdids));
+
+	ret = iavf_get_vf_supported_rxdids(adapter);
+	if (ret)
+		goto err;
+
+	/* We've processed the PF response to the
+	 * VIRTCHNL_OP_GET_SUPPORTED_RXDIDS message we sent previously.
+	 */
+	adapter->extended_caps &= ~IAVF_EXTENDED_CAP_RECV_RXDID;
+	return;
+
+err:
+	/* We didn't receive a reply. Make sure we try sending again when
+	 * __IAVF_INIT_FAILED attempts to recover.
+	 */
+	adapter->extended_caps |= IAVF_EXTENDED_CAP_SEND_RXDID;
+	iavf_change_state(adapter, __IAVF_INIT_FAILED);
+}
+
 /**
  * iavf_init_process_extended_caps - Part of driver startup
  * @adapter: board private structure
@@ -2623,6 +2718,15 @@ static void iavf_init_process_extended_caps(struct iavf_adapter *adapter)
 		return;
 	}
 
+	/* Process capability exchange for RXDID formats */
+	if (adapter->extended_caps & IAVF_EXTENDED_CAP_SEND_RXDID) {
+		iavf_init_send_supported_rxdids(adapter);
+		return;
+	} else if (adapter->extended_caps & IAVF_EXTENDED_CAP_RECV_RXDID) {
+		iavf_init_recv_supported_rxdids(adapter);
+		return;
+	}
+
 	/* When we reach here, no further extended capabilities exchanges are
 	 * necessary, so we finally transition into __IAVF_INIT_CONFIG_ADAPTER
 	 */
@@ -3139,15 +3243,18 @@ static void iavf_reset_task(struct work_struct *work)
 	}
 
 	adapter->aq_required |= IAVF_FLAG_AQ_GET_CONFIG;
-	/* always set since VIRTCHNL_OP_GET_VF_RESOURCES has not been
-	 * sent/received yet, so VLAN_V2_ALLOWED() cannot is not reliable here,
-	 * however the VIRTCHNL_OP_GET_OFFLOAD_VLAN_V2_CAPS won't be sent until
-	 * VIRTCHNL_OP_GET_VF_RESOURCES and VIRTCHNL_VF_OFFLOAD_VLAN_V2 have
-	 * been successfully sent and negotiated
-	 */
-	adapter->aq_required |= IAVF_FLAG_AQ_GET_OFFLOAD_VLAN_V2_CAPS;
 	adapter->aq_required |= IAVF_FLAG_AQ_MAP_VECTORS;
 
+	/* Certain capabilities require an extended negotiation process using
+	 * extra messages that must be processed after getting the VF
+	 * configuration. The related checks such as VLAN_V2_ALLOWED() are not
+	 * reliable here, since the configuration has not yet been negotiated.
+	 *
+	 * Always set these flags, since them related VIRTCHNL messages won't
+	 * be sent until after VIRTCHNL_OP_GET_VF_RESOURCES.
+	 */
+	adapter->aq_required |= IAVF_FLAG_AQ_EXTENDED_CAPS;
+
 	spin_lock_bh(&adapter->mac_vlan_list_lock);
 
 	/* Delete filter for the current MAC address, it could have

drivers/net/ethernet/intel/iavf/iavf_txrx.h

@@ -262,6 +262,8 @@ struct iavf_ring {
 	u16 next_to_use;
 	u16 next_to_clean;
 
+	u16 rxdid;		/* Rx descriptor format */
+
 	u16 flags;
 #define IAVF_TXR_FLAGS_WB_ON_ITR		BIT(0)
 #define IAVF_TXR_FLAGS_ARM_WB			BIT(1)

drivers/net/ethernet/intel/iavf/iavf_virtchnl.c

@@ -144,6 +144,7 @@ int iavf_send_vf_config_msg(struct iavf_adapter *adapter)
 	       VIRTCHNL_VF_OFFLOAD_ENCAP |
 	       VIRTCHNL_VF_OFFLOAD_TC_U32 |
 	       VIRTCHNL_VF_OFFLOAD_VLAN_V2 |
+	       VIRTCHNL_VF_OFFLOAD_RX_FLEX_DESC |
 	       VIRTCHNL_VF_OFFLOAD_CRC |
 	       VIRTCHNL_VF_OFFLOAD_ENCAP_CSUM |
 	       VIRTCHNL_VF_OFFLOAD_REQ_QUEUES |
@@ -177,6 +178,19 @@ int iavf_send_vf_offload_vlan_v2_msg(struct iavf_adapter *adapter)
 				NULL, 0);
 }
 
+int iavf_send_vf_supported_rxdids_msg(struct iavf_adapter *adapter)
+{
+	adapter->aq_required &= ~IAVF_FLAG_AQ_GET_SUPPORTED_RXDIDS;
+
+	if (!IAVF_RXDID_ALLOWED(adapter))
+		return -EOPNOTSUPP;
+
+	adapter->current_op = VIRTCHNL_OP_GET_SUPPORTED_RXDIDS;
+
+	return iavf_send_pf_msg(adapter, VIRTCHNL_OP_GET_SUPPORTED_RXDIDS,
+				NULL, 0);
+}
+
 /**
  * iavf_validate_num_queues
  * @adapter: adapter structure
@@ -263,6 +277,23 @@ int iavf_get_vf_vlan_v2_caps(struct iavf_adapter *adapter)
 	return err;
 }
 
+int iavf_get_vf_supported_rxdids(struct iavf_adapter *adapter)
+{
+	struct iavf_arq_event_info event;
+	u64 rxdids;
+	int err;
+
+	event.msg_buf = (u8 *)&rxdids;
+	event.buf_len = sizeof(rxdids);
+
+	err = iavf_poll_virtchnl_msg(&adapter->hw, &event,
+				     VIRTCHNL_OP_GET_SUPPORTED_RXDIDS);
+	if (!err)
+		adapter->supp_rxdids = rxdids;
+
+	return err;
+}
+
 /**
  * iavf_configure_queues
  * @adapter: adapter structure
@@ -309,6 +340,8 @@ void iavf_configure_queues(struct iavf_adapter *adapter)
 		vqpi->rxq.dma_ring_addr = adapter->rx_rings[i].dma;
 		vqpi->rxq.max_pkt_size = max_frame;
 		vqpi->rxq.databuffer_size = adapter->rx_rings[i].rx_buf_len;
+		if (IAVF_RXDID_ALLOWED(adapter))
+			vqpi->rxq.rxdid = adapter->rxdid;
 		if (CRC_OFFLOAD_ALLOWED(adapter))
 			vqpi->rxq.crc_disable = !!(adapter->netdev->features &
 						   NETIF_F_RXFCS);
@@ -2508,6 +2541,13 @@ void iavf_virtchnl_completion(struct iavf_adapter *adapter,
 		adapter->aq_required |= IAVF_FLAG_AQ_ADD_MAC_FILTER |
 			aq_required;
 		}
+		break;
+	case VIRTCHNL_OP_GET_SUPPORTED_RXDIDS:
+		if (msglen != sizeof(u64))
+			return;
+
+		adapter->supp_rxdids = *(u64 *)msg;
+
 		break;
 	case VIRTCHNL_OP_ENABLE_QUEUES:
 		/* enable transmits */

drivers/net/ethernet/intel/ice/ice_virtchnl.c

@@ -3040,8 +3040,8 @@ static int ice_vc_set_rss_hena(struct ice_vf *vf, u8 *msg)
 static int ice_vc_query_rxdid(struct ice_vf *vf)
 {
 	enum virtchnl_status_code v_ret = VIRTCHNL_STATUS_SUCCESS;
-	struct virtchnl_supported_rxdids rxdid = {};
 	struct ice_pf *pf = vf->pf;
+	u64 rxdid;
 
 	if (!test_bit(ICE_VF_STATE_ACTIVE, vf->vf_states)) {
 		v_ret = VIRTCHNL_STATUS_ERR_PARAM;
@@ -3053,7 +3053,7 @@ static int ice_vc_query_rxdid(struct ice_vf *vf)
 		goto err;
 	}
 
-	rxdid.supported_rxdids = pf->supported_rxdids;
+	rxdid = pf->supported_rxdids;
 
 err:
 	return ice_vc_send_msg_to_vf(vf, VIRTCHNL_OP_GET_SUPPORTED_RXDIDS,

include/linux/avf/virtchnl.h

@@ -1096,11 +1096,6 @@ struct virtchnl_filter {
 
 VIRTCHNL_CHECK_STRUCT_LEN(272, virtchnl_filter);
 
-struct virtchnl_supported_rxdids {
-	/* see enum virtchnl_rx_desc_id_bitmasks */
-	u64 supported_rxdids;
-};
-
 /* VIRTCHNL_OP_EVENT
  * PF sends this message to inform the VF driver of events that may affect it.
  * No direct response is expected from the VF, though it may generate other