From: Paul Barker Date: Tue, 15 Oct 2024 13:36:26 +0000 (+0100) Subject: net: ravb: Disable IP header RX checksum offloading X-Git-Tag: v6.13-rc1~135^2~287 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=c4e347a02b14fa2425337473fcb120c62936cbc5;p=thirdparty%2Fkernel%2Flinux.git net: ravb: Disable IP header RX checksum offloading For IPv4 packets, the header checksum will always be checked in software in the RX path (inet_gro_receive() calls ip_fast_csum() unconditionally) so there is no advantage in asking the hardware to also calculate this checksum. Reviewed-by: Sergey Shtylyov Signed-off-by: Paul Barker Signed-off-by: Andrew Lunn --- diff --git a/drivers/net/ethernet/renesas/ravb.h b/drivers/net/ethernet/renesas/ravb.h index 4e1e0a754cd93..98496aa39f3d9 100644 --- a/drivers/net/ethernet/renesas/ravb.h +++ b/drivers/net/ethernet/renesas/ravb.h @@ -1014,7 +1014,7 @@ enum CSR2_BIT { CSR2_RDHD = 0x08000000, }; -#define CSR2_CSUM_ENABLE (CSR2_RIP4 | CSR2_RTCP4 | CSR2_RUDP4 | CSR2_RICMP4) +#define CSR2_CSUM_ENABLE (CSR2_RTCP4 | CSR2_RUDP4 | CSR2_RICMP4) #define DBAT_ENTRY_NUM 22 #define RX_QUEUE_OFFSET 4 diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c index c8988c0c85a16..43db69d03684e 100644 --- a/drivers/net/ethernet/renesas/ravb_main.c +++ b/drivers/net/ethernet/renesas/ravb_main.c @@ -749,13 +749,18 @@ static void ravb_get_tx_tstamp(struct net_device *ndev) static void ravb_rx_csum_gbeth(struct sk_buff *skb) { struct skb_shared_info *shinfo = skb_shinfo(skb); - __wsum csum_ip_hdr, csum_proto; + __wsum csum_proto; skb_frag_t *last_frag; 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 checksum - * and last 2 bytes is protocol checksum. + * bytes appended to packet data. + * + * For ipv4, the first 2 bytes are the ip header checksum status. We can + * ignore this as it will always be re-checked in inet_gro_receive(). + * + * The last 2 bytes are the protocol checksum status which will be zero + * if the checksum has been validated. */ if (unlikely(skb->len < sizeof(__sum16) * 2)) return; @@ -771,16 +776,13 @@ static void ravb_rx_csum_gbeth(struct sk_buff *skb) hw_csum -= 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)); - if (skb_is_nonlinear(skb)) skb_frag_size_sub(last_frag, 2 * sizeof(__sum16)); else skb_trim(skb, skb->len - 2 * sizeof(__sum16)); /* TODO: IPV6 Rx checksum */ - if (skb->protocol == htons(ETH_P_IP) && !csum_ip_hdr && !csum_proto) + if (skb->protocol == htons(ETH_P_IP) && !csum_proto) skb->ip_summed = CHECKSUM_UNNECESSARY; }