[net-next v13 06/11] net: mtip: Add mtip_switch_{rx|tx} functions to the L2 switch driver
From: Lukasz Majewski <lukma@denx.de>
Date: 2025-06-22 09:38:36
Also in:
imx, linux-devicetree, lkml, netdev
Subsystem:
networking drivers, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
This patch provides mtip_switch_tx and mtip_switch_rx functions code for MTIP L2 switch. Signed-off-by: Lukasz Majewski <lukma@denx.de> --- Changes for v13: - New patch - created by excluding some code from large (i.e. v12 and earlier) MTIP driver --- .../net/ethernet/freescale/mtipsw/mtipl2sw.c | 252 ++++++++++++++++++ 1 file changed, 252 insertions(+)
diff --git a/drivers/net/ethernet/freescale/mtipsw/mtipl2sw.c b/drivers/net/ethernet/freescale/mtipsw/mtipl2sw.c
index 813cd39d6d56..a4e38e0d773e 100644
--- a/drivers/net/ethernet/freescale/mtipsw/mtipl2sw.c
+++ b/drivers/net/ethernet/freescale/mtipsw/mtipl2sw.c@@ -228,6 +228,39 @@ struct mtip_port_info *mtip_portinfofifo_read(struct switch_enet_private *fep) return info; } +static void mtip_atable_get_entry_port_number(struct switch_enet_private *fep, + unsigned char *mac_addr, u8 *port) +{ + int block_index, block_index_end, entry; + u32 mac_addr_lo, mac_addr_hi; + u32 read_lo, read_hi; + + mac_addr_lo = (u32)((mac_addr[3] << 24) | (mac_addr[2] << 16) | + (mac_addr[1] << 8) | mac_addr[0]); + mac_addr_hi = (u32)((mac_addr[5] << 8) | (mac_addr[4])); + + block_index = GET_BLOCK_PTR(crc8_calc(mac_addr)); + block_index_end = block_index + ATABLE_ENTRY_PER_SLOT; + + /* now search all the entries in the selected block */ + for (entry = block_index; entry < block_index_end; entry++) { + mtip_read_atable(fep, entry, &read_lo, &read_hi); + *port = MTIP_PORT_FORWARDING_INIT; + + if (read_lo == mac_addr_lo && + ((read_hi & 0x0000FFFF) == + (mac_addr_hi & 0x0000FFFF))) { + /* found the correct address */ + if ((read_hi & (1 << 16)) && (!(read_hi & (1 << 17)))) + *port = FIELD_GET(AT_PORT_MASK, read_hi); + break; + } + } + + dev_dbg(&fep->pdev->dev, "%s: MAC: %pM PORT: 0x%x\n", __func__, + mac_addr, *port); +} + /* Clear complete MAC Look Up Table */ void mtip_clear_atable(struct switch_enet_private *fep) {
@@ -820,10 +853,229 @@ static irqreturn_t mtip_interrupt(int irq, void *ptr_fep) static void mtip_switch_tx(struct net_device *dev) { + struct mtip_ndev_priv *priv = netdev_priv(dev); + struct switch_enet_private *fep = priv->fep; + unsigned short status; + struct sk_buff *skb; + unsigned long flags; + struct cbd_t *bdp; + + spin_lock_irqsave(&fep->hw_lock, flags); + bdp = fep->dirty_tx; + + while (((status = bdp->cbd_sc) & BD_ENET_TX_READY) == 0) { + if (bdp == fep->cur_tx && fep->tx_full == 0) + break; + + dma_unmap_single(&fep->pdev->dev, bdp->cbd_bufaddr, + MTIP_SWITCH_TX_FRSIZE, DMA_TO_DEVICE); + bdp->cbd_bufaddr = 0; + skb = fep->tx_skbuff[fep->skb_dirty]; + /* Check for errors */ + if (status & (BD_ENET_TX_HB | BD_ENET_TX_LC | + BD_ENET_TX_RL | BD_ENET_TX_UN | + BD_ENET_TX_CSL)) { + dev->stats.tx_errors++; + if (status & BD_ENET_TX_HB) /* No heartbeat */ + dev->stats.tx_heartbeat_errors++; + if (status & BD_ENET_TX_LC) /* Late collision */ + dev->stats.tx_window_errors++; + if (status & BD_ENET_TX_RL) /* Retrans limit */ + dev->stats.tx_aborted_errors++; + if (status & BD_ENET_TX_UN) /* Underrun */ + dev->stats.tx_fifo_errors++; + if (status & BD_ENET_TX_CSL) /* Carrier lost */ + dev->stats.tx_carrier_errors++; + } else { + dev->stats.tx_packets++; + } + + if (status & BD_ENET_TX_READY) + dev_err(&fep->pdev->dev, + "Enet xmit interrupt and TX_READY.\n"); + + /* Deferred means some collisions occurred during transmit, + * but we eventually sent the packet OK. + */ + if (status & BD_ENET_TX_DEF) + dev->stats.collisions++; + + /* Free the sk buffer associated with this last transmit */ + dev_consume_skb_irq(skb); + fep->tx_skbuff[fep->skb_dirty] = NULL; + fep->skb_dirty = (fep->skb_dirty + 1) & TX_RING_MOD_MASK; + + /* Update pointer to next buffer descriptor to be transmitted */ + if (status & BD_ENET_TX_WRAP) + bdp = fep->tx_bd_base; + else + bdp++; + + /* Since we have freed up a buffer, the ring is no longer + * full. + */ + if (fep->tx_full) { + fep->tx_full = 0; + if (netif_queue_stopped(dev)) + netif_wake_queue(dev); + } + } + fep->dirty_tx = bdp; + spin_unlock_irqrestore(&fep->hw_lock, flags); } +/* During a receive, the cur_rx points to the current incoming buffer. + * When we update through the ring, if the next incoming buffer has + * not been given to the system, we just set the empty indicator, + * effectively tossing the packet. + */ static int mtip_switch_rx(struct net_device *dev, int budget, int *port) { + struct mtip_ndev_priv *priv = netdev_priv(dev); + u8 *data, rx_port = MTIP_PORT_FORWARDING_INIT; + struct switch_enet_private *fep = priv->fep; + unsigned short status, pkt_len; + struct net_device *pndev; + struct ethhdr *eth_hdr; + int pkt_received = 0; + struct sk_buff *skb; + struct cbd_t *bdp; + struct page *page; + + spin_lock_bh(&fep->hw_lock); + + /* First, grab all of the stats for the incoming packet. + * These get messed up if we get called due to a busy condition. + */ + bdp = fep->cur_rx; + + while (!((status = bdp->cbd_sc) & BD_ENET_RX_EMPTY)) { + if (pkt_received >= budget) + break; + + pkt_received++; + /* Since we have allocated space to hold a complete frame, + * the last indicator should be set. + */ + if ((status & BD_ENET_RX_LAST) == 0) + dev_warn_ratelimited(&dev->dev, + "SWITCH ENET: rcv is not +last\n"); + + if (!fep->usage_count) + goto rx_processing_done; + + /* Check for errors. */ + if (status & (BD_ENET_RX_LG | BD_ENET_RX_SH | BD_ENET_RX_NO | + BD_ENET_RX_CR | BD_ENET_RX_OV)) { + dev->stats.rx_errors++; + if (status & (BD_ENET_RX_LG | BD_ENET_RX_SH)) { + /* Frame too long or too short. */ + dev->stats.rx_length_errors++; + } + if (status & BD_ENET_RX_NO) /* Frame alignment */ + dev->stats.rx_frame_errors++; + if (status & BD_ENET_RX_CR) /* CRC Error */ + dev->stats.rx_crc_errors++; + if (status & BD_ENET_RX_OV) /* FIFO overrun */ + dev->stats.rx_fifo_errors++; + } + + /* Report late collisions as a frame error. + * On this error, the BD is closed, but we don't know what we + * have in the buffer. So, just drop this frame on the floor. + */ + if (status & BD_ENET_RX_CL) { + dev->stats.rx_errors++; + dev->stats.rx_frame_errors++; + goto rx_processing_done; + } + + /* Get correct RX page */ + page = fep->page[bdp - fep->rx_bd_base]; + /* Process the incoming frame */ + pkt_len = bdp->cbd_datlen; + data = (__u8 *)__va(bdp->cbd_bufaddr); + + dma_sync_single_for_cpu(&fep->pdev->dev, bdp->cbd_bufaddr, + pkt_len, DMA_FROM_DEVICE); + prefetch(page_address(page)); + + if (fep->quirks & FEC_QUIRK_SWAP_FRAME) + swap_buffer(data, pkt_len); + + if (data) { + eth_hdr = (struct ethhdr *)data; + mtip_atable_get_entry_port_number(fep, + eth_hdr->h_source, + &rx_port); + if (rx_port == MTIP_PORT_FORWARDING_INIT) + mtip_atable_dynamicms_learn_migration(fep, + fep->curr_time, + eth_hdr->h_source, + &rx_port); + } + + if ((rx_port == 1 || rx_port == 2) && fep->ndev[rx_port - 1]) + pndev = fep->ndev[rx_port - 1]; + else + pndev = dev; + + *port = rx_port; + + /* This does 16 byte alignment, exactly what we need. + * The packet length includes FCS, but we don't want to + * include that when passing upstream as it messes up + * bridging applications. + */ + skb = netdev_alloc_skb(pndev, pkt_len + NET_IP_ALIGN); + if (unlikely(!skb)) { + dev_dbg(&fep->pdev->dev, + "%s: Memory squeeze, dropping packet.\n", + pndev->name); + page_pool_recycle_direct(fep->page_pool, page); + pndev->stats.rx_dropped++; + goto err_mem; + } else { + skb_reserve(skb, NET_IP_ALIGN); + skb_put(skb, pkt_len); /* Make room */ + skb_copy_to_linear_data(skb, data, pkt_len); + skb->protocol = eth_type_trans(skb, pndev); + napi_gro_receive(&fep->napi, skb); + } + + pndev->stats.rx_packets++; + pndev->stats.rx_bytes += pkt_len; + + rx_processing_done: + /* Clear the status flags for this buffer */ + status &= ~BD_ENET_RX_STATS; + + /* Mark the buffer empty */ + status |= BD_ENET_RX_EMPTY; + /* Make sure that updates to the descriptor are performed */ + wmb(); + bdp->cbd_sc = status; + + /* Update BD pointer to next entry */ + if (status & BD_ENET_RX_WRAP) + bdp = fep->rx_bd_base; + else + bdp++; + + /* Doing this here will keep the FEC running while we process + * incoming frames. On a heavily loaded network, we should be + * able to keep up at the expense of system resources. + */ + writel(MCF_ESW_RDAR_R_DES_ACTIVE, fep->hwp + ESW_RDAR); + } /* while (!((status = bdp->cbd_sc) & BD_ENET_RX_EMPTY)) */ + + fep->cur_rx = bdp; + spin_unlock_bh(&fep->hw_lock); + + return pkt_received; + + err_mem: + spin_unlock_bh(&fep->hw_lock); return -ENOMEM; }
--
2.39.5