Re: [RFC/PATCH 16/18] ravb: Add Packet receive function for Gigabit Ethernet
From: Sergey Shtylyov <hidden>
Date: 2021-10-01 17:28:02
Also in:
linux-renesas-soc
On 9/23/21 5:08 PM, Biju Das wrote:
quoted hunk ↗ jump to hunk
This patch series adds RX(packet receive) function for Gigabit Ethernet found on RZ/G2L SoC. Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> --- drivers/net/ethernet/renesas/ravb.h | 1 + drivers/net/ethernet/renesas/ravb_main.c | 157 ++++++++++++++++++++++- 2 files changed, 156 insertions(+), 2 deletions(-)diff --git a/drivers/net/ethernet/renesas/ravb.h b/drivers/net/ethernet/renesas/ravb.h index b0e067a6a8ee..85260f89e1cd 100644 --- a/drivers/net/ethernet/renesas/ravb.h +++ b/drivers/net/ethernet/renesas/ravb.h@@ -1092,6 +1092,7 @@ struct ravb_private { int duplex; struct ravb_rx_desc *rgeth_rx_ring[NUM_RX_QUEUE]; + struct sk_buff *rxtop_skb;
I'd prefer for this one declared earler in the *struct*, as well. And why not e.g 'rx_1st_skb'?
quoted hunk ↗ jump to hunk
const struct ravb_hw_info *info; struct reset_control *rstc;diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c index a08da7a37b92..867e180e6655 100644 --- a/drivers/net/ethernet/renesas/ravb_main.c +++ b/drivers/net/ethernet/renesas/ravb_main.c@@ -705,6 +705,23 @@ static void ravb_get_tx_tstamp(struct net_device *ndev) } } +static void ravb_rx_csum_rgeth(struct sk_buff *skb) +{ + u8 *hw_csum; + + /* The hardware checksum is contained in sizeof(__sum16) (2) bytes + * appended to packet data + */ + if (unlikely(skb->len < sizeof(__sum16))) + return; + hw_csum = skb_tail_pointer(skb) - sizeof(__sum16); + + if (*hw_csum == 0) + skb->ip_summed = CHECKSUM_UNNECESSARY; + else + skb->ip_summed = CHECKSUM_NONE;
Mhm, what's the point of this whole function then? Why it can't be a copy of the R-Car analog? [...]
quoted hunk ↗ jump to hunk
@@ -720,11 +737,147 @@ static void ravb_rx_csum(struct sk_buff *skb)
[...]
/* Packet receive function for Gigabit Ethernet */
static bool ravb_rgeth_rx(struct net_device *ndev, int *quota, int q)
{
- /* Place holder */
- return true;
+ struct ravb_private *priv = netdev_priv(ndev);
+ int entry = priv->cur_rx[q] % priv->num_rx_ring[q];
+ int boguscnt = priv->dirty_rx[q] + priv->num_rx_ring[q] - priv->cur_rx[q];
+ struct net_device_stats *stats = &priv->stats[q];[q] should be dropped, as we've agreed...
+ struct ravb_rx_desc *desc;
+ struct sk_buff *skb;
+ dma_addr_t dma_addr;
+ u8 desc_status;
+ u8 die_dt;
+ u16 pkt_len;
+ int limit;
+
+ boguscnt = min(boguscnt, *quota);
+ limit = boguscnt;
+ desc = &priv->rgeth_rx_ring[q][entry];
+ while (desc->die_dt != DT_FEMPTY) {
+ /* Descriptor type must be checked before all other reads */
+ dma_rmb();
+ desc_status = desc->msc;
+ pkt_len = le16_to_cpu(desc->ds_cc) & RX_DS;
+
+ if (--boguscnt < 0)
+ break;
+
+ /* We use 0-byte descriptors to mark the DMA mapping errors */
+ if (!pkt_len)
+ continue;
+
+ if (desc_status & MSC_MC)
+ stats->multicast++;
+
+ if (desc_status & (MSC_CRC | MSC_RFE | MSC_RTSF | MSC_RTLF | MSC_CEEF)) {
+ stats->rx_errors++;
+ if (desc_status & MSC_CRC)
+ stats->rx_crc_errors++;
+ if (desc_status & MSC_RFE)
+ stats->rx_frame_errors++;
+ if (desc_status & (MSC_RTLF | MSC_RTSF))
+ stats->rx_length_errors++;
+ if (desc_status & MSC_CEEF)
+ stats->rx_missed_errors++;
+ } else {
+ die_dt = desc->die_dt & 0xF0;
+ switch (die_dt) {
+ case DT_FSINGLE:
+ skb = ravb_get_skb_rgeth(ndev, q, entry, desc);
+ skb_put(skb, pkt_len);
+ skb->protocol = eth_type_trans(skb, ndev);
+ if (ndev->features & NETIF_F_RXCSUM)
+ ravb_rx_csum_rgeth(skb);
+ napi_gro_receive(&priv->napi[q], skb);
+ stats->rx_packets++;
+ stats->rx_bytes += pkt_len;
+ break;
+ case DT_FSTART:
+ priv->rxtop_skb = ravb_get_skb_rgeth(ndev, q, entry, desc);But don't you need to copy the data in this case?
+ skb_put(priv->rxtop_skb, pkt_len);
+ break;
+ case DT_FMID:
+ skb = ravb_get_skb_rgeth(ndev, q, entry, desc);
+ skb_copy_to_linear_data_offset(priv->rxtop_skb,
+ priv->rxtop_skb->len,
+ skb->data,
+ pkt_len);
+ skb_put(priv->rxtop_skb, pkt_len);
+ dev_kfree_skb(skb);
+ break;
+ case DT_FEND:
+ skb = ravb_get_skb_rgeth(ndev, q, entry, desc);
+ skb_copy_to_linear_data_offset(priv->rxtop_skb,
+ priv->rxtop_skb->len,
+ skb->data,
+ pkt_len);
+ skb_put(priv->rxtop_skb, pkt_len);
+ dev_kfree_skb(skb);
+ priv->rxtop_skb->protocol =
+ eth_type_trans(priv->rxtop_skb, ndev);
+ if (ndev->features & NETIF_F_RXCSUM)
+ ravb_rx_csum_rgeth(skb);
+ napi_gro_receive(&priv->napi[q],
+ priv->rxtop_skb);
+ stats->rx_packets++;
+ stats->rx_bytes += priv->rxtop_skb->len;
+ break;
+ }
+ }
+
+ entry = (++priv->cur_rx[q]) % priv->num_rx_ring[q];
+ desc = &priv->rgeth_rx_ring[q][entry];
+ }
+
+ /* Refill the RX ring buffers. */
+ for (; priv->cur_rx[q] - priv->dirty_rx[q] > 0; priv->dirty_rx[q]++) {
+ entry = priv->dirty_rx[q] % priv->num_rx_ring[q];
+ desc = &priv->rgeth_rx_ring[q][entry];
+ desc->ds_cc = cpu_to_le16(RGETH_RX_DESC_DATA_SIZE);
+
+ if (!priv->rx_skb[q][entry]) {
+ skb = netdev_alloc_skb(ndev,
+ RGETH_RX_BUFF_MAX + RAVB_ALIGN - 1);ALIGN(RGETH_RX_BUFF_MAX, RAVB_ALIGN)? [...] MBR, Sergey