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 Tx checksum offload supported by TOE for IPv4 and TCP/UDP.
>
> For Tx, the result of checksum calculation is set to the checksum field of
> each IPv4 Header/TCP/UDP/ICMP of ethernet frames. For the unsupported
> frames, those fields are not changed. If a transmission frame is an UDPv4
> frame and its checksum value in the UDP header field is 0x0000, TOE does
> not calculate checksum for UDP part of this frame as it is optional
> function as per standards.
>
> We can test this functionality by the below commands
>
> ethtool -K eth0 tx on --> to turn on Tx checksum offload
> ethtool -K eth0 tx off --> to turn off Tx checksum offload
>
> Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
> ---
> v2->v3:
> * Updated commit header and description as suggested by Sergey.
> * Replaced NETIF_F_IP_CSUM->NETIF_F_HW_CSUM as we are supporting only IPv4.
You do vice versa, NETIF_F_HW_CSUM->NETIF_F_IP_CSUM. :-)
However, I'm now seeing this comment under CHECKSM_PATIAL:
* %NETIF_F_IP_CSUM and %NETIF_F_IPV6_CSUM are being deprecated in favor of
* %NETIF_F_HW_CSUM. New devices should use %NETIF_F_HW_CSUM to indicate
* checksum offload capability.
So probably we should've kept NETIF_F_HW_CSUM? :-/
> * Updated the comment related to UDP header field.
> * Renamed ravb_is_tx_checksum_offload_gbeth_possible()->ravb_is_tx_csum_gbeth().
> v1->v2:
> * No change.
[...]
> diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
> index c4dc6ec54287..042dc565d1a5 100644
> --- a/drivers/net/ethernet/renesas/ravb_main.c
> +++ b/drivers/net/ethernet/renesas/ravb_main.c
[...]
> @@ -524,15 +525,27 @@ static int ravb_ring_init(struct net_device *ndev, int q)
>
> static void ravb_csum_init_gbeth(struct net_device *ndev)
> {
> - if (!(ndev->features & NETIF_F_RXCSUM))
> + bool tx_enable = ndev->features & NETIF_F_IP_CSUM;
> + bool rx_enable = ndev->features & NETIF_F_RXCSUM;
> +
> + if (!(tx_enable || rx_enable))
> goto done;
>
> ravb_write(ndev, 0, CSR0);
> - if (ravb_wait(ndev, CSR0, CSR0_RPE, 0)) {
> + if (ravb_wait(ndev, CSR0, CSR0_TPE | CSR0_RPE, 0)) {
> netdev_err(ndev, "Timeout enabling hardware checksum\n");
> - ndev->features &= ~NETIF_F_RXCSUM;
> +
> + if (tx_enable)
> + ndev->features &= ~NETIF_F_IP_CSUM;
> +
> + if (rx_enable)
> + ndev->features &= ~NETIF_F_RXCSUM;
> } else {
> - ravb_write(ndev, CSR2_ALL, CSR2);
> + if (tx_enable)
> + ravb_write(ndev, CSR1_ALL, CSR1);
> +
> + if (rx_enable)
> + ravb_write(ndev, CSR2_ALL, CSR2);
> }
>
> done:
> @@ -1986,6 +1999,35 @@ static void ravb_tx_timeout_work(struct work_struct *work)
> rtnl_unlock();
> }
>
> +static bool ravb_is_tx_csum_gbeth(struct sk_buff *skb)
Hm, this new name doesn't parse well for me... :-(
Maybe ravb_can_tx_csum_gbeth() or ravb_tx_csum_possible_gbeth()?
> +{
> + struct iphdr *ip = ip_hdr(skb);
> +
> + /* TODO: Need to add support for VLAN tag 802.1Q */
> + if (skb_vlan_tag_present(skb))
> + return false;
> +
> + switch (ip->protocol) {
> + case IPPROTO_TCP:
> + break;
> + case IPPROTO_UDP:
> + /* If the checksum value in the UDP header field is 0, TOE does
> + * not calculate checksum for UDP part of this frame as it is
> + * optional function as per standards.
> + */
> + if (udp_hdr(skb)->check == 0)
> + return false;
> + break;
> + /* TODO: Need to add HW checksum for ICMP */
s/HW/hardware/?
> + case IPPROTO_ICMP:
> + fallthrough;
You don't even need fallthrough, actually...
But why do you return false for ICMP? Isn't it supported by TOE?
> + default:
> + return false;
> + }
> +
> + return true;
> +}
> +
> /* Packet transmit function for Ethernet AVB */
> static netdev_tx_t ravb_start_xmit(struct sk_buff *skb, struct net_device *ndev)
> {
[...]
MBR, Sergey
