On 2/1/24 10:45 PM, Biju Das wrote:
> TOE has hardware support for calculating IP header and TCP/UDP/ICMP
> checksum for both IPv4 and IPv6.
>
> Add Rx checksum offload supported by TOE for IPv4 and TCP/UDP protocols.
>
> For Rx, the 4-byte result of checksum calculation is attached to the
> Ethernet frames.First 2-bytes is result of IPv4 header checksum and next
> 2-bytes is TCP/UDP/ICMP checksum.
>
> If a frame does not have checksum error, 0x0000 is attached as checksum
> calculation result. For unsupported frames 0xFFFF is attached as checksum
> calculation result. In case of an IPv6 packet, IPv4 checksum is always set
> to 0xFFFF.
>
> We can test this functionality by the below commands
>
> ethtool -K eth0 rx on --> to turn on Rx checksum offload
> ethtool -K eth0 rx off --> to turn off Rx checksum offload
>
> Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
[...]
> diff --git a/drivers/net/ethernet/renesas/ravb.h b/drivers/net/ethernet/renesas/ravb.h
> index e0f8276cffed..a7fe9d8b6b41 100644
> --- a/drivers/net/ethernet/renesas/ravb.h
> +++ b/drivers/net/ethernet/renesas/ravb.h
> @@ -206,6 +206,7 @@ enum ravb_reg {
> RFCR = 0x0760,
> MAFCR = 0x0778,
Would be good to add this comment here:
/* TOE registers */
> CSR0 = 0x0800, /* RZ/G2L only */
> + CSR2 = 0x0808, /* RZ/G2L only */
> };
>
>
[...]
> diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
> index 0e3731f50fc2..c4dc6ec54287 100644
> --- a/drivers/net/ethernet/renesas/ravb_main.c
> +++ b/drivers/net/ethernet/renesas/ravb_main.c
> @@ -522,6 +522,23 @@ static int ravb_ring_init(struct net_device *ndev, int q)
> return -ENOMEM;
> }
>
> +static void ravb_csum_init_gbeth(struct net_device *ndev)
> +{
> + if (!(ndev->features & NETIF_F_RXCSUM))
> + goto done;
> +
> + ravb_write(ndev, 0, CSR0);
> + if (ravb_wait(ndev, CSR0, CSR0_RPE, 0)) {
> + netdev_err(ndev, "Timeout enabling hardware checksum\n");
> + ndev->features &= ~NETIF_F_RXCSUM;
> + } else {
> + ravb_write(ndev, CSR2_ALL, CSR2);
Does it make sense to set the IPv6 specific bits if we don't yet
support IPv6 checksumming anyways?
> + }
> +
> +done:
> + ravb_write(ndev, CSR0_TPE | CSR0_RPE, CSR0);
> +}
> +
> static void ravb_emac_init_gbeth(struct net_device *ndev)
> {
> struct ravb_private *priv = netdev_priv(ndev);
[...]
> @@ -734,6 +752,31 @@ static void ravb_get_tx_tstamp(struct net_device *ndev)
> }
> }
>
> +static void ravb_rx_csum_gbeth(struct sk_buff *skb)
> +{
> + __wsum csum_ip_hdr, csum_proto;
> + u8 *hw_csum;
> +
> + /* The hardware checksum status is contained in sizeof(__sum16) * 2 = 4
> + * bytes appended to packet data. First 2 bytes is ip header csum and
> + * last 2 bytes is protocol csum.
Hm, maybe spell out csum as checksum?
> + */
> + if (unlikely(skb->len < sizeof(__sum16) * 2))
> + return;
> +
> + hw_csum = skb_tail_pointer(skb) - sizeof(__sum16);
> + csum_proto = csum_unfold((__force __sum16)get_unaligned_le16(hw_csum));
> +
> + hw_csum -= sizeof(__sum16);
> + csum_ip_hdr = csum_unfold((__force __sum16)get_unaligned_le16(hw_csum));
> + skb_trim(skb, skb->len - 2 * sizeof(__sum16));
> +
> + /* TODO: IPV6 Rx csum */
> + if (skb->protocol == htons(ETH_P_IP) && !csum_ip_hdr && !csum_proto)
> + /* Hardware validated our checksum */
> + skb->ip_summed = CHECKSUM_UNNECESSARY;
I think you need {} because of the comment (but would be good without it
as well)...
[...]
> @@ -2334,11 +2381,49 @@ static void ravb_set_rx_csum(struct net_device *ndev, bool enable)
> spin_unlock_irqrestore(&priv->lock, flags);
> }
>
> +static int ravb_endisable_csum_gbeth(struct net_device *ndev, enum ravb_reg reg,
> + u32 val, u32 mask)
I'd suggest to mimic ravb_wait() with the the mask param followed by
the val[ue] param...
> +{
> + u32 csr0;
> + int ret;
> +
> + csr0 = ravb_read(ndev, CSR0);
Hm... I think we already know CSR0's value as ravb_csum_init_gbeth()
sets it to (CSR0_TPE | CSR0_RPE) on exit...
> + ravb_write(ndev, csr0 & ~mask, CSR0);
> + ret = ravb_wait(ndev, CSR0, mask, 0);
> + if (!ret)
> + ravb_write(ndev, val, reg);
> +
> + ravb_write(ndev, csr0, CSR0);
> +
> + return ret;
> +}
> +
> static int ravb_set_features_gbeth(struct net_device *ndev,
> netdev_features_t features)
> {
> - /* Place holder */
> - return 0;
> + netdev_features_t changed = ndev->features ^ features;
> + struct ravb_private *priv = netdev_priv(ndev);
> + unsigned long flags;
> + int ret = 0;
> + u32 val;
> +
> + spin_lock_irqsave(&priv->lock, flags);
> + if (changed & NETIF_F_RXCSUM) {
> + if (features & NETIF_F_RXCSUM)
> + val = CSR2_ALL;
Again, does it make sense to set the IPv6 bits in CSR2?
> + else
> + val = 0;
> +
> + ret = ravb_endisable_csum_gbeth(ndev, CSR2, val, CSR0_RPE);
> + if (ret)
> + goto done;
> + }
> +
> + ndev->features = features;
> +done:
> + spin_unlock_irqrestore(&priv->lock, flags);
> +
> + return ret;
> }
>
> static int ravb_set_features_rcar(struct net_device *ndev,
[...]
MBR, Sergey
