ice: add E830 Earliest TxTime First Offload support

E830 supports Earliest TxTime First (ETF) hardware offload, which is
configured via the ETF Qdisc on a per-queue basis (see tc-etf(8)). ETF
introduces a new Tx flow mechanism that utilizes a timestamp ring
(tstamp_ring) alongside the standard Tx ring. This timestamp ring is
used to indicate when hardware will transmit a packet. Tx Time is
supported on the first 2048 Tx queues of the device, and the NVM image
limits the maximum number of Tx queues to 2048 for the device.

The allocation and initialization of the timestamp ring occur when the
feature is enabled on a specific Tx queue via tc-etf. The requested Tx
Time queue index cannot be greater than the number of Tx queues
(vsi->num_txq).

To support ETF, the following flags and bitmap are introduced:

 - ICE_F_TXTIME: Device feature flag set for E830 NICs, indicating ETF
   support.
 - txtime_txqs: PF-level bitmap set when ETF is enabled and cleared
   when disabled for a specific Tx queue. It is used by
   ice_is_txtime_ena() to check if ETF is allocated and configured on
   any Tx queue, which is checked during Tx ring allocation.
 - ICE_TX_FLAGS_TXTIME: Per Tx ring flag set when ETF is allocated and
   configured for a specific Tx queue. It determines ETF status during
   packet transmission and is checked by ice_is_txtime_ena() to verify
   if ETF is enabled on any Tx queue.

Due to a hardware issue that can result in a malicious driver detection
event, additional timestamp descriptors are required when wrapping
around the timestamp ring. Up to 64 additional timestamp descriptors
are reserved, reducing the available Tx descriptors.

To accommodate this, ICE_MAX_NUM_DESC_BY_MAC is introduced, defining:

 - E830: Maximum Tx descriptor count of 8096 (8K - 32 - 64 for timestamp
   fetch descriptors).
 - E810 and E82X: Maximum Tx descriptor count of 8160 (8K - 32).

Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Co-developed-by: Alice Michael <alice.michael@intel.com>
Signed-off-by: Alice Michael <alice.michael@intel.com>
Signed-off-by: Paul Greenwalt <paul.greenwalt@intel.com>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Tested-by: Rinitha S <sx.rinitha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

1 files changed, 108 insertions, 1 deletions

diff --git a/drivers/net/ethernet/intel/ice/ice_main.c b/drivers/net/ethernet/intel/ice/ice_main.c
index f0d3aee24a93..86f5859e88ef 100644
--- a/drivers/net/ethernet/intel/ice/ice_main.c
+++ b/drivers/net/ethernet/intel/ice/ice_main.c
@@ -3969,6 +3969,11 @@ static void ice_deinit_pf(struct ice_pf *pf)
 		pf->avail_rxqs = NULL;
 	}
 
+	if (pf->txtime_txqs) {
+		bitmap_free(pf->txtime_txqs);
+		pf->txtime_txqs = NULL;
+	}
+
 	if (pf->ptp.clock)
 		ptp_clock_unregister(pf->ptp.clock);
 
@@ -4062,6 +4067,15 @@ static int ice_init_pf(struct ice_pf *pf)
 		return -ENOMEM;
 	}
 
+	pf->txtime_txqs = bitmap_zalloc(pf->max_pf_txqs, GFP_KERNEL);
+	if (!pf->txtime_txqs) {
+		bitmap_free(pf->avail_txqs);
+		pf->avail_txqs = NULL;
+		bitmap_free(pf->avail_rxqs);
+		pf->avail_rxqs = NULL;
+		return -ENOMEM;
+	}
+
 	mutex_init(&pf->vfs.table_lock);
 	hash_init(pf->vfs.table);
 	if (ice_is_feature_supported(pf, ICE_F_MBX_LIMIT))
@@ -7484,7 +7498,8 @@ int ice_vsi_open(struct ice_vsi *vsi)
 	if (err)
 		goto err_setup_rx;
 
-	ice_vsi_cfg_netdev_tc(vsi, vsi->tc_cfg.ena_tc);
+	if (bitmap_empty(pf->txtime_txqs, pf->max_pf_txqs))
+		ice_vsi_cfg_netdev_tc(vsi, vsi->tc_cfg.ena_tc);
 
 	if (vsi->type == ICE_VSI_PF || vsi->type == ICE_VSI_SF) {
 		/* Notify the stack of the actual queue counts. */
@@ -9273,6 +9288,96 @@ exit:
 	return ret;
 }
 
+/**
+ * ice_cfg_txtime - configure Tx Time for the Tx ring
+ * @tx_ring: pointer to the Tx ring structure
+ *
+ * Return: 0 on success, negative value on failure.
+ */
+static int ice_cfg_txtime(struct ice_tx_ring *tx_ring)
+{
+	int err, timeout = 50;
+	struct ice_vsi *vsi;
+	struct device *dev;
+	struct ice_pf *pf;
+	u32 queue;
+
+	if (!tx_ring)
+		return -EINVAL;
+
+	vsi = tx_ring->vsi;
+	pf = vsi->back;
+	while (test_and_set_bit(ICE_CFG_BUSY, pf->state)) {
+		timeout--;
+		if (!timeout)
+			return -EBUSY;
+		usleep_range(1000, 2000);
+	}
+
+	queue = tx_ring->q_index;
+	dev = ice_pf_to_dev(pf);
+
+	/* Ignore return value, and always attempt to enable queue. */
+	ice_qp_dis(vsi, queue);
+
+	err = ice_qp_ena(vsi, queue);
+	if (err)
+		dev_err(dev, "Failed to enable Tx queue %d for TxTime configuration\n",
+			queue);
+
+	clear_bit(ICE_CFG_BUSY, pf->state);
+	return err;
+}
+
+/**
+ * ice_offload_txtime - set earliest TxTime first
+ * @netdev: network interface device structure
+ * @qopt_off: etf queue option offload from the skb to set
+ *
+ * Return: 0 on success, negative value on failure.
+ */
+static int ice_offload_txtime(struct net_device *netdev,
+			      void *qopt_off)
+{
+	struct ice_netdev_priv *np = netdev_priv(netdev);
+	struct ice_pf *pf = np->vsi->back;
+	struct tc_etf_qopt_offload *qopt;
+	struct ice_vsi *vsi = np->vsi;
+	struct ice_tx_ring *tx_ring;
+	int ret = 0;
+
+	if (!ice_is_feature_supported(pf, ICE_F_TXTIME))
+		return -EOPNOTSUPP;
+
+	qopt = qopt_off;
+	if (!qopt_off || qopt->queue < 0 || qopt->queue >= vsi->num_txq)
+		return -EINVAL;
+
+	if (qopt->enable)
+		set_bit(qopt->queue,  pf->txtime_txqs);
+	else
+		clear_bit(qopt->queue, pf->txtime_txqs);
+
+	if (netif_running(vsi->netdev)) {
+		tx_ring = vsi->tx_rings[qopt->queue];
+		ret = ice_cfg_txtime(tx_ring);
+		if (ret)
+			goto err;
+	}
+
+	netdev_info(netdev, "%s TxTime on queue: %i\n",
+		    str_enable_disable(qopt->enable), qopt->queue);
+	return 0;
+
+err:
+	netdev_err(netdev, "Failed to %s TxTime on queue: %i\n",
+		   str_enable_disable(qopt->enable), qopt->queue);
+
+	if (qopt->enable)
+		clear_bit(qopt->queue,  pf->txtime_txqs);
+	return ret;
+}
+
 static LIST_HEAD(ice_block_cb_list);
 
 static int
@@ -9336,6 +9441,8 @@ adev_unlock:
 			mutex_unlock(&pf->adev_mutex);
 		}
 		return err;
+	case TC_SETUP_QDISC_ETF:
+		return ice_offload_txtime(netdev, type_data);
 	default:
 		return -EOPNOTSUPP;
 	}