[PATCH net-next 0/2] Add HW check sum of load for RZ/G2L GbEthernet IP

[PATCH net-next 0/2] Add HW check sum of load for RZ/G2L GbEthernet IP

[Biju Das]

TOE has hw support for calculating IP header and TCP/UDP/ICMP checksum
for both IPV4 and IPV6.

Add Tx/Rx checksum offload supported by TOE for IPV4 and TCP/UDP protocols.

For Rx, the result of checksum calculation is attached to last 4byte
of ethernet frames. First 2bytes is result of IPV4 header checksum
and next 2 bytes is TCP/UDP/ICMP.

If frame does not have error "0000" attached to checksum calculation
result. For unsupported frames "ffff" is attached to checksum calculation
result. Cases like IPV6, IPV4 header is always set to "FFFF".

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 UDP
frame of IPv4 and its checksum value in the UDP header field is H’0000,
TOE does not calculate checksum for UDP part of this frame as it is
optional function as per standards.

UDP(Tx/Rx) results With check Enabled: 909/946
UDP(Tx/Rx) results With check Disabled: 903/907

TCP(Tx/Rx) results With check Enabled: 922/928
TCP(Tx/Rx) results With check Disabled: 882/629

Note:
 This patches are tested with reverting 
commit b3edde44e5d4 ("cpufreq/schedutil: Use a fixed reference frequency")
as it impacts network performance.

Biju Das (2):
  ravb: Add Rx checksum offload support
  ravb: Add Tx checksum offload support

 drivers/net/ethernet/renesas/ravb.h      |  35 ++++++
 drivers/net/ethernet/renesas/ravb_main.c | 137 ++++++++++++++++++++++-
 2 files changed, 170 insertions(+), 2 deletions(-)

-- 
2.25.1

[PATCH net-next 1/2] ravb: Add Rx checksum offload support

[Biju Das]

TOE has hw 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 result of checksum calculation is attached to last 4byte
of ethernet frames. First 2bytes is result of IPV4 header checksum
and next 2 bytes is TCP/UDP/ICMP.

If frame does not have error "0000" attached to checksum calculation
result. For unsupported frames "ffff" is attached to checksum calculation
result. Cases like IPV6, IPV4 header is always set to "FFFF".

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@bp.renesas.com>
---
 drivers/net/ethernet/renesas/ravb.h      | 19 ++++++
 drivers/net/ethernet/renesas/ravb_main.c | 81 +++++++++++++++++++++++-
 2 files changed, 98 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/renesas/ravb.h b/drivers/net/ethernet/renesas/ravb.h
index e0f8276cffed..a2c494a85d12 100644
--- a/drivers/net/ethernet/renesas/ravb.h
+++ b/drivers/net/ethernet/renesas/ravb.h
@@ -44,6 +44,9 @@
 #define RAVB_RXTSTAMP_TYPE_ALL	0x00000006
 #define RAVB_RXTSTAMP_ENABLED	0x00000010	/* Enable RX timestamping */
 
+/* GbEthernet TOE hardware checksum values */
+#define TOE_RX_CSUM_OK	0x0000
+
 enum ravb_reg {
 	/* AVB-DMAC registers */
 	CCC	= 0x0000,
@@ -206,6 +209,7 @@ enum ravb_reg {
 	RFCR	= 0x0760,
 	MAFCR	= 0x0778,
 	CSR0    = 0x0800,	/* RZ/G2L only */
+	CSR2    = 0x0808,	/* RZ/G2L only */
 };
 
 
@@ -978,6 +982,21 @@ enum CSR0_BIT {
 	CSR0_RPE	= 0x00000020,
 };
 
+enum CSR2_BIT {
+	CSR2_RIP4	= 0x00000001,
+	CSR2_RTCP4	= 0x00000010,
+	CSR2_RUDP4	= 0x00000020,
+	CSR2_RICMP4	= 0x00000040,
+	CSR2_RTCP6	= 0x00100000,
+	CSR2_RUDP6	= 0x00200000,
+	CSR2_RICMP6	= 0x00400000,
+	CSR2_RHOP	= 0x01000000,
+	CSR2_RROUT	= 0x02000000,
+	CSR2_RAHD	= 0x04000000,
+	CSR2_RDHD	= 0x08000000,
+	CSR2_ALL	= 0x0F700071,
+};
+
 #define DBAT_ENTRY_NUM	22
 #define RX_QUEUE_OFFSET	4
 #define NUM_RX_QUEUE	2
diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
index 0e3731f50fc2..219eb9f0391c 100644
--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c
@@ -522,6 +522,26 @@ static int ravb_ring_init(struct net_device *ndev, int q)
 	return -ENOMEM;
 }
 
+static void ravb_csum_offload_init_gbeth(struct net_device *ndev)
+{
+	bool rx_enable = ndev->features & NETIF_F_RXCSUM;
+	u32 csr0;
+
+	if (!rx_enable)
+		return;
+
+	csr0 = ravb_read(ndev, CSR0);
+	ravb_write(ndev, csr0 & ~(CSR0_RPE | CSR0_TPE), CSR0);
+	if (ravb_wait(ndev, CSR0, CSR0_RPE | CSR0_TPE, 0)) {
+		netdev_err(ndev, "Timeout Enabling HW CSUM failed\n");
+		ndev->features &= ~NETIF_F_RXCSUM;
+	} else {
+		ravb_write(ndev, CSR2_ALL, CSR2);
+	}
+
+	ravb_write(ndev, csr0, CSR0);
+}
+
 static void ravb_emac_init_gbeth(struct net_device *ndev)
 {
 	struct ravb_private *priv = netdev_priv(ndev);
@@ -543,6 +563,7 @@ static void ravb_emac_init_gbeth(struct net_device *ndev)
 			 ECMR_TE | ECMR_RE | ECMR_RCPT |
 			 ECMR_TXF | ECMR_RXF, ECMR);
 
+	ravb_csum_offload_init_gbeth(ndev);
 	ravb_set_rate_gbeth(ndev);
 
 	/* Set MAC address */
@@ -734,6 +755,32 @@ static void ravb_get_tx_tstamp(struct net_device *ndev)
 	}
 }
 
+static void ravb_rx_csum_gbeth(struct sk_buff *skb)
+{
+	__sum16 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.
+	 */
+	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 == TOE_RX_CSUM_OK &&
+	    csum_proto == TOE_RX_CSUM_OK)
+		/* Hardware validated our checksum */
+		skb->ip_summed = CHECKSUM_UNNECESSARY;
+}
+
 static void ravb_rx_csum(struct sk_buff *skb)
 {
 	u8 *hw_csum;
@@ -819,6 +866,8 @@ static bool ravb_rx_gbeth(struct net_device *ndev, int *quota, int q)
 				skb = ravb_get_skb_gbeth(ndev, entry, desc);
 				skb_put(skb, pkt_len);
 				skb->protocol = eth_type_trans(skb, ndev);
+				if (ndev->features & NETIF_F_RXCSUM)
+					ravb_rx_csum_gbeth(skb);
 				napi_gro_receive(&priv->napi[q], skb);
 				stats->rx_packets++;
 				stats->rx_bytes += pkt_len;
@@ -846,6 +895,8 @@ static bool ravb_rx_gbeth(struct net_device *ndev, int *quota, int q)
 				dev_kfree_skb(skb);
 				priv->rx_1st_skb->protocol =
 					eth_type_trans(priv->rx_1st_skb, ndev);
+				if (ndev->features & NETIF_F_RXCSUM)
+					ravb_rx_csum_gbeth(skb);
 				napi_gro_receive(&priv->napi[q],
 						 priv->rx_1st_skb);
 				stats->rx_packets++;
@@ -2337,8 +2388,32 @@ static void ravb_set_rx_csum(struct net_device *ndev, bool enable)
 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;
+	u32 csr0;
+	int ret;
+
+	spin_lock_irqsave(&priv->lock, flags);
+	csr0 = ravb_read(ndev, CSR0);
+	ravb_write(ndev, csr0 & ~(CSR0_RPE | CSR0_TPE), CSR0);
+	ret = ravb_wait(ndev, CSR0, CSR0_RPE | CSR0_TPE, 0);
+	if (ret)
+		goto err_wait;
+
+	if (changed & NETIF_F_RXCSUM) {
+		if (features & NETIF_F_RXCSUM)
+			ravb_write(ndev, CSR2_ALL, CSR2);
+		else
+			ravb_write(ndev, 0, CSR2);
+	}
+
+	ndev->features = features;
+err_wait:
+	ravb_write(ndev, csr0, CSR0);
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	return ret;
 }
 
 static int ravb_set_features_rcar(struct net_device *ndev,
@@ -2518,6 +2593,8 @@ static const struct ravb_hw_info gbeth_hw_info = {
 	.emac_init = ravb_emac_init_gbeth,
 	.gstrings_stats = ravb_gstrings_stats_gbeth,
 	.gstrings_size = sizeof(ravb_gstrings_stats_gbeth),
+	.net_hw_features = NETIF_F_RXCSUM,
+	.net_features = NETIF_F_RXCSUM,
 	.stats_len = ARRAY_SIZE(ravb_gstrings_stats_gbeth),
 	.max_rx_len = ALIGN(GBETH_RX_BUFF_MAX, RAVB_ALIGN),
 	.tccr_mask = TCCR_TSRQ0,
-- 
2.25.1

[PATCH net-next 2/2] ravb: Add Tx checksum offload support

[Biju Das]

TOE has hw 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 UDP
frame of IPv4 and its checksum value in the UDP header field is H’0000,
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@bp.renesas.com>
---
 drivers/net/ethernet/renesas/ravb.h      | 16 ++++++
 drivers/net/ethernet/renesas/ravb_main.c | 66 ++++++++++++++++++++++--
 2 files changed, 77 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/renesas/ravb.h b/drivers/net/ethernet/renesas/ravb.h
index a2c494a85d12..3cf869fb9a68 100644
--- a/drivers/net/ethernet/renesas/ravb.h
+++ b/drivers/net/ethernet/renesas/ravb.h
@@ -209,6 +209,7 @@ enum ravb_reg {
 	RFCR	= 0x0760,
 	MAFCR	= 0x0778,
 	CSR0    = 0x0800,	/* RZ/G2L only */
+	CSR1    = 0x0804,	/* RZ/G2L only */
 	CSR2    = 0x0808,	/* RZ/G2L only */
 };
 
@@ -982,6 +983,21 @@ enum CSR0_BIT {
 	CSR0_RPE	= 0x00000020,
 };
 
+enum CSR1_BIT {
+	CSR1_TIP4	= 0x00000001,
+	CSR1_TTCP4	= 0x00000010,
+	CSR1_TUDP4	= 0x00000020,
+	CSR1_TICMP4	= 0x00000040,
+	CSR1_TTCP6	= 0x00100000,
+	CSR1_TUDP6	= 0x00200000,
+	CSR1_TICMP6	= 0x00400000,
+	CSR1_THOP	= 0x01000000,
+	CSR1_TROUT	= 0x02000000,
+	CSR1_TAHD	= 0x04000000,
+	CSR1_TDHD	= 0x08000000,
+	CSR1_ALL	= 0x0F700071,
+};
+
 enum CSR2_BIT {
 	CSR2_RIP4	= 0x00000001,
 	CSR2_RTCP4	= 0x00000010,
diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
index 219eb9f0391c..7f7a26f698cb 100644
--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c
@@ -29,6 +29,7 @@
 #include <linux/spinlock.h>
 #include <linux/reset.h>
 #include <linux/math64.h>
+#include <net/ip.h>
 
 #include "ravb.h"
 
@@ -524,19 +525,29 @@ static int ravb_ring_init(struct net_device *ndev, int q)
 
 static void ravb_csum_offload_init_gbeth(struct net_device *ndev)
 {
+	bool tx_enable = ndev->features & NETIF_F_HW_CSUM;
 	bool rx_enable = ndev->features & NETIF_F_RXCSUM;
 	u32 csr0;
 
-	if (!rx_enable)
+	if (!(tx_enable || rx_enable))
 		return;
 
 	csr0 = ravb_read(ndev, CSR0);
 	ravb_write(ndev, csr0 & ~(CSR0_RPE | CSR0_TPE), CSR0);
 	if (ravb_wait(ndev, CSR0, CSR0_RPE | CSR0_TPE, 0)) {
 		netdev_err(ndev, "Timeout Enabling HW CSUM failed\n");
-		ndev->features &= ~NETIF_F_RXCSUM;
+
+		if (tx_enable)
+			ndev->features &= ~NETIF_F_HW_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);
 	}
 
 	ravb_write(ndev, csr0, CSR0);
@@ -1990,6 +2001,39 @@ static void ravb_tx_timeout_work(struct work_struct *work)
 	rtnl_unlock();
 }
 
+static bool ravb_is_tx_checksum_offload_gbeth_possible(struct sk_buff *skb)
+{
+	struct iphdr *ip = ip_hdr(skb);
+
+	/* TODO: Need to add support for VLAN tag 802.1Q */
+	if (skb_vlan_tag_present(skb))
+		return false;
+
+	/* TODO: Need to add HW checksum for IPV6 */
+	if (skb->protocol != htons(ETH_P_IP))
+		return false;
+
+	switch (ip->protocol) {
+	case IPPROTO_TCP:
+		break;
+	case IPPROTO_UDP:
+		/* If the checksum value in the UDP header field is “H’0000”,
+		 * 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 */
+	case IPPROTO_ICMP:
+		fallthrough;
+	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)
 {
@@ -2005,6 +2049,11 @@ static netdev_tx_t ravb_start_xmit(struct sk_buff *skb, struct net_device *ndev)
 	u32 entry;
 	u32 len;
 
+	if (skb->ip_summed == CHECKSUM_PARTIAL) {
+		if (!ravb_is_tx_checksum_offload_gbeth_possible(skb))
+			skb_checksum_help(skb);
+	}
+
 	spin_lock_irqsave(&priv->lock, flags);
 	if (priv->cur_tx[q] - priv->dirty_tx[q] > (priv->num_tx_ring[q] - 1) *
 	    num_tx_desc) {
@@ -2408,6 +2457,13 @@ static int ravb_set_features_gbeth(struct net_device *ndev,
 			ravb_write(ndev, 0, CSR2);
 	}
 
+	if (changed & NETIF_F_HW_CSUM) {
+		if (features & NETIF_F_HW_CSUM)
+			ravb_write(ndev, CSR1_ALL, CSR1);
+		else
+			ravb_write(ndev, 0, CSR1);
+	}
+
 	ndev->features = features;
 err_wait:
 	ravb_write(ndev, csr0, CSR0);
@@ -2593,8 +2649,8 @@ static const struct ravb_hw_info gbeth_hw_info = {
 	.emac_init = ravb_emac_init_gbeth,
 	.gstrings_stats = ravb_gstrings_stats_gbeth,
 	.gstrings_size = sizeof(ravb_gstrings_stats_gbeth),
-	.net_hw_features = NETIF_F_RXCSUM,
-	.net_features = NETIF_F_RXCSUM,
+	.net_hw_features = NETIF_F_RXCSUM | NETIF_F_HW_CSUM,
+	.net_features = NETIF_F_RXCSUM | NETIF_F_HW_CSUM,
 	.stats_len = ARRAY_SIZE(ravb_gstrings_stats_gbeth),
 	.max_rx_len = ALIGN(GBETH_RX_BUFF_MAX, RAVB_ALIGN),
 	.tccr_mask = TCCR_TSRQ0,
-- 
2.25.1

Re: [PATCH net-next 1/2] ravb: Add Rx checksum offload support

[Jakub Kicinski]

On Tue, 23 Jan 2024 15:19:23 +0000 Biju Das wrote:
> +static void ravb_rx_csum_gbeth(struct sk_buff *skb)
> +{
> +	__sum16 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.
> +	 */
> +	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 == TOE_RX_CSUM_OK &&
> +	    csum_proto == TOE_RX_CSUM_OK)
> +		/* Hardware validated our checksum */
> +		skb->ip_summed = CHECKSUM_UNNECESSARY;
> +}

sparse does not seem to be onboard:

drivers/net/ethernet/renesas/ravb_main.c:771:20: warning: incorrect type in assignment (different base types)
drivers/net/ethernet/renesas/ravb_main.c:771:20:    expected restricted __sum16 [usertype] csum_proto
drivers/net/ethernet/renesas/ravb_main.c:771:20:    got restricted __wsum
drivers/net/ethernet/renesas/ravb_main.c:774:21: warning: incorrect type in assignment (different base types)
drivers/net/ethernet/renesas/ravb_main.c:774:21:    expected restricted __sum16 [usertype] csum_ip_hdr
drivers/net/ethernet/renesas/ravb_main.c:774:21:    got restricted __wsum
-- 
pw-bot: cr

RE: [PATCH net-next 1/2] ravb: Add Rx checksum offload support

[Biju Das]

Hi Jakub Kicinski,

Thanks for the feedback.

> -----Original Message-----
> From: Jakub Kicinski <kuba@kernel.org>
> Sent: Wednesday, January 24, 2024 1:09 AM
> Subject: Re: [PATCH net-next 1/2] ravb: Add Rx checksum offload support
> 
> On Tue, 23 Jan 2024 15:19:23 +0000 Biju Das wrote:
> > +static void ravb_rx_csum_gbeth(struct sk_buff *skb) {
> > +	__sum16 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.
> > +	 */
> > +	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 ==
> TOE_RX_CSUM_OK &&
> > +	    csum_proto == TOE_RX_CSUM_OK)
> > +		/* Hardware validated our checksum */
> > +		skb->ip_summed = CHECKSUM_UNNECESSARY; }
> 
> sparse does not seem to be onboard:
> 
> drivers/net/ethernet/renesas/ravb_main.c:771:20: warning: incorrect type
> in assignment (different base types)
> drivers/net/ethernet/renesas/ravb_main.c:771:20:    expected restricted
> __sum16 [usertype] csum_proto
> drivers/net/ethernet/renesas/ravb_main.c:771:20:    got restricted __wsum
> drivers/net/ethernet/renesas/ravb_main.c:774:21: warning: incorrect type
> in assignment (different base types)
> drivers/net/ethernet/renesas/ravb_main.c:774:21:    expected restricted
> __sum16 [usertype] csum_ip_hdr
> drivers/net/ethernet/renesas/ravb_main.c:774:21:    got restricted __wsum

I have reproduced this issue and the warning is fixed by replacing
__sum16->__wsum.

I will send v2 with this fix.

Cheers,
Biju

Re: [PATCH net-next 1/2] ravb: Add Rx checksum offload support

[Sergey Shtylyov]

On 1/24/24 11:31 AM, Biju Das wrote:
[...]

>> -----Original Message-----
>> From: Jakub Kicinski <kuba@kernel.org>
>> Sent: Wednesday, January 24, 2024 1:09 AM
>> Subject: Re: [PATCH net-next 1/2] ravb: Add Rx checksum offload support
>>
>> On Tue, 23 Jan 2024 15:19:23 +0000 Biju Das wrote:
>>> +static void ravb_rx_csum_gbeth(struct sk_buff *skb) {
>>> +	__sum16 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.
>>> +	 */
>>> +	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 ==
>> TOE_RX_CSUM_OK &&
>>> +	    csum_proto == TOE_RX_CSUM_OK)
>>> +		/* Hardware validated our checksum */
>>> +		skb->ip_summed = CHECKSUM_UNNECESSARY; }
>>
>> sparse does not seem to be onboard:
>>
>> drivers/net/ethernet/renesas/ravb_main.c:771:20: warning: incorrect type
>> in assignment (different base types)
>> drivers/net/ethernet/renesas/ravb_main.c:771:20:    expected restricted
>> __sum16 [usertype] csum_proto
>> drivers/net/ethernet/renesas/ravb_main.c:771:20:    got restricted __wsum
>> drivers/net/ethernet/renesas/ravb_main.c:774:21: warning: incorrect type
>> in assignment (different base types)
>> drivers/net/ethernet/renesas/ravb_main.c:774:21:    expected restricted
>> __sum16 [usertype] csum_ip_hdr
>> drivers/net/ethernet/renesas/ravb_main.c:774:21:    got restricted __wsum
> 
> I have reproduced this issue and the warning is fixed by replacing
> __sum16->__wsum.
> 
> I will send v2 with this fix.

   You could have waited for my review...
   Dave, Jakub, please don't merge these patches before I have a chance
to review them. I'm overwhelmed by reviews (both internal and public)
ATM... :-/

> Cheers,
> Biju

MBR, Sergey

RE: [PATCH net-next 1/2] ravb: Add Rx checksum offload support

[Biju Das]

Hi Sergey Shtylyov,

> -----Original Message-----
> From: Sergey Shtylyov <s.shtylyov@omp.ru>
> Sent: Wednesday, January 24, 2024 8:51 PM
> Subject: Re: [PATCH net-next 1/2] ravb: Add Rx checksum offload support
> 
> On 1/24/24 11:31 AM, Biju Das wrote:
> [...]
> 
> >> -----Original Message-----
> >> From: Jakub Kicinski <kuba@kernel.org>
> >> Sent: Wednesday, January 24, 2024 1:09 AM
> >> Subject: Re: [PATCH net-next 1/2] ravb: Add Rx checksum offload
> >> support
> >>
> >> On Tue, 23 Jan 2024 15:19:23 +0000 Biju Das wrote:
> >>> +static void ravb_rx_csum_gbeth(struct sk_buff *skb) {
> >>> +	__sum16 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.
> >>> +	 */
> >>> +	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 ==
> >> TOE_RX_CSUM_OK &&
> >>> +	    csum_proto == TOE_RX_CSUM_OK)
> >>> +		/* Hardware validated our checksum */
> >>> +		skb->ip_summed = CHECKSUM_UNNECESSARY; }
> >>
> >> sparse does not seem to be onboard:
> >>
> >> drivers/net/ethernet/renesas/ravb_main.c:771:20: warning: incorrect
> >> type in assignment (different base types)
> >> drivers/net/ethernet/renesas/ravb_main.c:771:20:    expected restricted
> >> __sum16 [usertype] csum_proto
> >> drivers/net/ethernet/renesas/ravb_main.c:771:20:    got restricted
> __wsum
> >> drivers/net/ethernet/renesas/ravb_main.c:774:21: warning: incorrect
> >> type in assignment (different base types)
> >> drivers/net/ethernet/renesas/ravb_main.c:774:21:    expected restricted
> >> __sum16 [usertype] csum_ip_hdr
> >> drivers/net/ethernet/renesas/ravb_main.c:774:21:    got restricted
> __wsum
> >
> > I have reproduced this issue and the warning is fixed by replacing
> > __sum16->__wsum.
> >
> > I will send v2 with this fix.
> 
>    You could have waited for my review...

Please review the latest version v2[2] as it is fixing bot error.
It is straight forward, and simpler patches should be fast to review.

[2] https://lore.kernel.org/all/20240124102115.132154-1-biju.das.jz@bp.renesas.com/

Cheers,
Biju

>    Dave, Jakub, please don't merge these patches before I have a chance to
> review them. I'm overwhelmed by reviews (both internal and public)
> ATM... :-/
> 
> > Cheers,
> > Biju
> 
> MBR, Sergey