[PATCH net-next v7 3/6] idpf: support pacing offload

@@ -604,6 +604,16 @@ struct idpf_vport_config {
 	DECLARE_BITMAP(flags, IDPF_VPORT_CONFIG_FLAGS_NBITS);
 };
 
+/**
+ * struct idpf_edt_caps_ilog2 - Host parsed EDT capabilities.
+ * @time_horizon_ns: Total time window in nanoseconds.
+ * @tstamp_granularity_pow2: Log2 of timestamp granularity in nanoseconds.
+ */
+struct idpf_edt_caps_ilog2 {
+	u32 time_horizon_ns;
+	u8 tstamp_granularity_pow2;
+};
+
 #define idpf_for_each_vport(adapter, iter) \
 	for (struct idpf_vport **__##iter = &(adapter)->vports[0], \
 	     *iter = (adapter)->max_vports ? *__##iter : NULL; \

@@ -657,6 +667,7 @@ struct idpf_vport_config {
  * @stats_task: Periodic statistics retrieval task
  * @stats_wq: Workqueue for statistics task
  * @caps: Negotiated capabilities with device
+ * @edt_caps: Negotiated EDT capabilities with device
  * @dev_ops: See idpf_dev_ops
  * @cdev_info: IDC core device info pointer
  * @num_vfs: Number of allocated VFs through sysfs. PF does not directly talk

@@ -720,6 +731,7 @@ struct idpf_adapter {
 	struct delayed_work stats_task;
 	struct workqueue_struct *stats_wq;
 	struct virtchnl2_get_capabilities caps;
+	struct idpf_edt_caps_ilog2 edt_caps;
 
 	struct idpf_dev_ops dev_ops;
 	struct iidc_rdma_core_dev_info *cdev_info;

@@ -890,6 +890,12 @@ static int idpf_cfg_netdev(struct idpf_vport *vport)
 	netdev->min_mtu = ETH_MIN_MTU;
 	netdev->max_mtu = vport->max_mtu;
 
+	if (adapter->edt_caps.time_horizon_ns &&
+	    idpf_is_queue_model_split(vport->dflt_qv_rsrc.txq_model) &&
+	    !idpf_is_cap_ena(adapter, IDPF_OTHER_CAPS,
+			     VIRTCHNL2_CAP_SPLITQ_QSCHED))
+		netdev->max_pacing_offload_horizon = adapter->edt_caps.time_horizon_ns;
+
 	dflt_features = NETIF_F_SG	|
 			NETIF_F_HIGHDMA;
 

@@ -1742,6 +1742,7 @@ static int idpf_txq_group_alloc(struct idpf_vport *vport,
 			q->desc_count = rsrc->txq_desc_count;
 			q->tx_max_bufs = idpf_get_max_tx_bufs(adapter);
 			q->tx_min_pkt_len = idpf_get_min_tx_pkt_len(adapter);
+			q->ts_gran_pow2 = adapter->edt_caps.tstamp_granularity_pow2;
 			q->netdev = vport->netdev;
 			q->txq_grp = tx_qgrp;
 			q->rel_q_id = j;

@@ -2408,7 +2409,12 @@ void idpf_tx_splitq_build_flow_desc(union idpf_tx_flex_desc *desc,
 				    struct idpf_tx_splitq_params *params,
 				    u16 td_cmd, u16 size)
 {
-	*(__le32 *)&desc->flow.qw1.cmd_dtype = cpu_to_le32((u8)(params->dtype | td_cmd));
+	desc->flow.qw1.cmd_dtype = (u8)(params->dtype | td_cmd);
+
+	desc->flow.qw1.ts[0] = params->offload.desc_ts[0];
+	desc->flow.qw1.ts[1] = params->offload.desc_ts[1];
+	desc->flow.qw1.ts[2] = params->offload.desc_ts[2];
+
 	desc->flow.qw1.rxr_bufsize = cpu_to_le16((u16)size);
 	desc->flow.qw1.compl_tag = cpu_to_le16(params->compl_tag);
 }

@@ -3011,6 +3017,61 @@ static bool idpf_tx_splitq_need_re(struct idpf_tx_queue *tx_q)
 	return gap >= IDPF_TX_SPLITQ_RE_MIN_GAP;
 }
 
+static void idpf_tx_splitq_set_txtime(const struct sk_buff *skb,
+				      const struct idpf_tx_queue *tx_q,
+				      struct idpf_tx_splitq_params *tx_params)
+{
+	const int offload_slack_ns = 400;
+	struct idpf_netdev_priv *np = netdev_priv(skb->dev);
+	u64 ts, now, horizon;
+
+	horizon = READ_ONCE(skb->dev->pacing_offload_horizon);
+	if (!horizon)
+		return;
+
+	switch (skb->tstamp_type) {
+	case SKB_CLOCK_REALTIME:
+		ts = ktime_to_ns(ktime_add(skb->tstamp,
+					   ktime_mono_to_any(0, TK_OFFS_TAI) -
+					   ktime_mono_to_any(0, TK_OFFS_REAL)));
+		break;
+	case SKB_CLOCK_MONOTONIC:
+		ts = ktime_to_ns(ktime_mono_to_any(skb->tstamp, TK_OFFS_TAI));
+		break;
+	case SKB_CLOCK_TAI:
+		ts = ktime_to_ns(skb->tstamp);
+		break;
+	default:
+		WARN_ON_ONCE(1);
+		return;
+	}
+
+	now = ktime_get_clocktai_ns();
+	if (ts < now + offload_slack_ns)
+		return;
+
+	/* beyond offload horizon? set overflow bit only */
+	if (ts > now + horizon) {
+		tx_params->offload.desc_ts[2] =
+			IDPF_TXD_FLOW_SCH_HORIZON_OVERFLOW_M;
+		return;
+	}
+
+	ts >>= tx_q->ts_gran_pow2;
+
+	/* 0 is valid 23b timestamp, but also means field unset.
+	 * Increase by one to avoid this case
+	 */
+	if ((ts & 0x7fffff) == 0) {
+		tx_params->offload.desc_ts[0] = 1;
+		return;
+	}
+
+	tx_params->offload.desc_ts[0] = ts & 0xff;
+	tx_params->offload.desc_ts[1] = (ts >> 8) & 0xff;
+	tx_params->offload.desc_ts[2] = ((ts >> 16) & 0x7f);
+}
+
 /**
  * idpf_tx_splitq_frame - Sends buffer on Tx ring using flex descriptors
  * @skb: send buffer

@@ -3097,6 +3158,10 @@ static netdev_tx_t idpf_tx_splitq_frame(struct sk_buff *skb,
 
 		tx_params.dtype = IDPF_TX_DESC_DTYPE_FLEX_FLOW_SCHE;
 		tx_params.eop_cmd = IDPF_TXD_FLEX_FLOW_CMD_EOP;
+
+		if (skb->tstamp)
+			idpf_tx_splitq_set_txtime(skb, tx_q, &tx_params);
+
 		/* Set the RE bit periodically to "clean" the descriptor ring */
 		if (idpf_tx_splitq_need_re(tx_q)) {
 			tx_params.eop_cmd |= IDPF_TXD_FLEX_FLOW_CMD_RE;

@@ -161,6 +161,7 @@ union idpf_tx_flex_desc {
  * @tso_segs: Number of segments to be sent
  * @tso_hdr_len: Length of headers to be duplicated
  * @td_cmd: Command field to be inserted into descriptor
+ * @desc_ts: Flow scheduling offload timestamp
  */
 struct idpf_tx_offload_params {
 	u32 tx_flags;

@@ -174,6 +175,7 @@ struct idpf_tx_offload_params {
 	u16 tso_hdr_len;
 
 	u16 td_cmd;
+	u8 desc_ts[3];
 };
 
 /**

@@ -608,6 +610,7 @@ libeth_cacheline_set_assert(struct idpf_rx_queue,
  *	 hot path TX pointers stored in vport. Used in both singleq/splitq.
  * @desc_count: Number of descriptors
  * @tx_min_pkt_len: Min supported packet length
+ * @ts_gran_pow2: Txtime timestamp granularity in nanoseconds (log2).
  * @thresh: XDP queue cleaning threshold
  * @netdev: &net_device corresponding to this queue
  * @next_to_use: Next descriptor to use

@@ -666,7 +669,10 @@ struct idpf_tx_queue {
 	u16 desc_count;
 
 	union {
-		u16 tx_min_pkt_len;
+		struct {
+			u16 tx_min_pkt_len;
+			u8 ts_gran_pow2;
+		};
 		u32 thresh;
 	};
 

@@ -3,6 +3,7 @@
 
 #include <linux/export.h>
 #include <linux/net/intel/libie/pci.h>
+#include <linux/log2.h>
 #include <net/libeth/rx.h>
 
 #include "idpf.h"

@@ -553,7 +554,8 @@ static int idpf_send_get_caps_msg(struct idpf_adapter *adapter)
 			    VIRTCHNL2_CAP_SPLITQ_QSCHED		|
 			    VIRTCHNL2_CAP_PROMISC		|
 			    VIRTCHNL2_CAP_LOOPBACK		|
-			    VIRTCHNL2_CAP_PTP);
+			    VIRTCHNL2_CAP_PTP			|
+			    VIRTCHNL2_CAP_EDT);
 
 	err = idpf_send_mb_msg_stack(adapter, &xn_params, &caps);
 	if (err)

@@ -573,6 +575,54 @@ static int idpf_send_get_caps_msg(struct idpf_adapter *adapter)
 	return err;
 }
 
+/**
+ * idpf_send_get_edt_caps_msg - Send virtchnl get EDT caps msg
+ * @adapter: Driver specific private struct
+ *
+ * Return: 0 on success or error code on failure.
+ */
+static int idpf_send_get_edt_caps_msg(struct idpf_adapter *adapter)
+{
+	struct libie_ctlq_xn_send_params xn_params = {
+		.timeout_ms	= IDPF_VC_XN_DEFAULT_TIMEOUT_MSEC,
+		.chnl_opcode	= VIRTCHNL2_OP_GET_EDT_CAPS,
+	};
+	struct virtchnl2_edt_caps caps = {};
+	u64 gran_ns, horizon_ns;
+	int err;
+
+	err = idpf_send_mb_msg_stack(adapter, &xn_params, &caps);
+	if (err)
+		return err;
+
+	if (xn_params.recv_mem.iov_len < sizeof(caps)) {
+		err = -EIO;
+		goto free_rx_buf;
+	}
+
+	memcpy(&caps, xn_params.recv_mem.iov_base, sizeof(caps));
+	horizon_ns = le64_to_cpu(caps.time_horizon_ns);
+	gran_ns = le64_to_cpu(caps.tstamp_granularity_ns);
+	if (horizon_ns > U32_MAX) {
+		dev_warn(&adapter->pdev->dev, "EDT horizon exceeds U32\n");
+		err = -EINVAL;
+		goto free_rx_buf;
+	}
+	if (!gran_ns) {
+		dev_warn(&adapter->pdev->dev, "EDT granularity undefined\n");
+		err = -EINVAL;
+		goto free_rx_buf;
+	}
+
+	adapter->edt_caps.time_horizon_ns = horizon_ns;
+	adapter->edt_caps.tstamp_granularity_pow2 = ilog2(gran_ns);
+
+free_rx_buf:
+	libie_ctlq_release_rx_buf(&xn_params.recv_mem);
+
+	return err;
+}
+
 /**
  * idpf_mmio_region_non_static - Check if region is not static
  * @mmio_info: PCI resources info

@@ -3085,6 +3135,14 @@ int idpf_vc_core_init(struct idpf_adapter *adapter)
 		}
 	}
 
+	if (idpf_is_cap_ena(adapter, IDPF_OTHER_CAPS, VIRTCHNL2_CAP_EDT)) {
+		err = idpf_send_get_edt_caps_msg(adapter);
+		if (err) {
+			dev_err(&adapter->pdev->dev, "EDT init failed, err=%d\n", err);
+			memset(&adapter->edt_caps, 0, sizeof(adapter->edt_caps));
+		}
+	}
+
 	pci_sriov_set_totalvfs(adapter->pdev, idpf_get_max_vfs(adapter));
 	num_max_vports = idpf_get_max_vports(adapter);
 	adapter->vports = kzalloc_objs(*adapter->vports, num_max_vports);