2013-07-21 08:35:59

by Vladimir Kondratiev

[permalink] [raw]
Subject: [PATCH 0/2] wil6210 checksum offload

Next ready for integration patches. This time, introduce checksum offload
by Erez. Other patch is pre-requisite for checksum patch, and for more
offload patches that are coming.

Kirshenbaum Erez (1):
wil6210: Enable TCP/UDP checksum HW offload

Vladimir Kondratiev (1):
wil6210: fix error path in wil_tx_vring

drivers/net/wireless/ath/wil6210/netdev.c | 2 +
drivers/net/wireless/ath/wil6210/txrx.c | 83 +++++++++++++++++++++++++++++--
drivers/net/wireless/ath/wil6210/txrx.h | 20 +++++++-
drivers/net/wireless/ath/wil6210/wmi.c | 6 +++
4 files changed, 105 insertions(+), 6 deletions(-)

--
1.8.1.2



2013-07-21 08:35:49

by Vladimir Kondratiev

[permalink] [raw]
Subject: [PATCH 1/2] wil6210: fix error path in wil_tx_vring

Release fragments in the order of allocation; including one for skb head

Signed-off-by: Vladimir Kondratiev <[email protected]>
---
drivers/net/wireless/ath/wil6210/txrx.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/ath/wil6210/txrx.c b/drivers/net/wireless/ath/wil6210/txrx.c
index 2a9d56a..e563af1 100644
--- a/drivers/net/wireless/ath/wil6210/txrx.c
+++ b/drivers/net/wireless/ath/wil6210/txrx.c
@@ -730,12 +730,13 @@ static int wil_tx_vring(struct wil6210_priv *wil, struct vring *vring,
return 0;
dma_error:
/* unmap what we have mapped */
- /* Note: increment @f to operate with positive index */
- for (f++; f > 0; f--) {
+ nr_frags = f + 1; /* frags mapped + one for skb head */
+ for (f = 0; f < nr_frags; f++) {
u16 dmalen;
- struct wil_ctx *ctx = &vring->ctx[i];
+ struct wil_ctx *ctx;

i = (swhead + f) % vring->size;
+ ctx = &vring->ctx[i];
_d = &(vring->va[i].tx);
*d = *_d;
_d->dma.status = TX_DMA_STATUS_DU;
--
1.8.1.2


2013-07-21 08:35:52

by Vladimir Kondratiev

[permalink] [raw]
Subject: [PATCH 2/2] wil6210: Enable TCP/UDP checksum HW offload

From: Kirshenbaum Erez <[email protected]>

Add support for TCP and UDP HW checksum offloading.
RX chain is allways configured for offload mode.
In case of checksum error in RX path the DMA L4 error bit(5)
will be set to 1 and driver will drop the packet.
TX checksum offloading is configrable (ethtool -K).
TX descriptors are configured for checksum offload according
to the SKB protocol type (TCP/UDP, IPV4/6), Upon mismatch drop
the TX packet (checksum required but not TCP/UDP IPV4/6 type).

Signed-off-by: Kirshenbaum Erez <[email protected]>
Signed-off-by: Vladimir Kondratiev <[email protected]>
---
drivers/net/wireless/ath/wil6210/netdev.c | 2 +
drivers/net/wireless/ath/wil6210/txrx.c | 76 ++++++++++++++++++++++++++++++-
drivers/net/wireless/ath/wil6210/txrx.h | 20 +++++++-
drivers/net/wireless/ath/wil6210/wmi.c | 6 +++
4 files changed, 101 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/ath/wil6210/netdev.c b/drivers/net/wireless/ath/wil6210/netdev.c
index 29dd1e5..717178f 100644
--- a/drivers/net/wireless/ath/wil6210/netdev.c
+++ b/drivers/net/wireless/ath/wil6210/netdev.c
@@ -127,6 +127,8 @@ void *wil_if_alloc(struct device *dev, void __iomem *csr)

ndev->netdev_ops = &wil_netdev_ops;
ndev->ieee80211_ptr = wdev;
+ ndev->hw_features = NETIF_F_HW_CSUM | NETIF_F_RXCSUM;
+ ndev->features |= NETIF_F_HW_CSUM | NETIF_F_RXCSUM;
SET_NETDEV_DEV(ndev, wiphy_dev(wdev->wiphy));
wdev->netdev = ndev;

diff --git a/drivers/net/wireless/ath/wil6210/txrx.c b/drivers/net/wireless/ath/wil6210/txrx.c
index e563af1..ea1abeb 100644
--- a/drivers/net/wireless/ath/wil6210/txrx.c
+++ b/drivers/net/wireless/ath/wil6210/txrx.c
@@ -18,6 +18,9 @@
#include <net/ieee80211_radiotap.h>
#include <linux/if_arp.h>
#include <linux/moduleparam.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <net/ipv6.h>

#include "wil6210.h"
#include "wmi.h"
@@ -407,6 +410,21 @@ static struct sk_buff *wil_vring_reap_rx(struct wil6210_priv *wil,
return NULL;
}

+ /* L4 IDENT is on when HW calculated checksum, check status
+ * and in case of error drop the packet
+ * higher stack layers will handle retransmission (if required)
+ */
+ if (d->dma.status & RX_DMA_STATUS_L4_IDENT) {
+ /* L4 protocol identified, csum calculated */
+ if ((d->dma.error & RX_DMA_ERROR_L4_ERR) == 0) {
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+ } else {
+ wil_err(wil, "Incorrect checksum reported\n");
+ kfree_skb(skb);
+ return NULL;
+ }
+ }
+
ds_bits = wil_rxdesc_ds_bits(d);
if (ds_bits == 1) {
/*
@@ -646,6 +664,53 @@ static int wil_tx_desc_map(struct vring_tx_desc *d, dma_addr_t pa, u32 len,
return 0;
}

+static int wil_tx_desc_offload_cksum_set(struct wil6210_priv *wil,
+ struct vring_tx_desc *d,
+ struct sk_buff *skb)
+{
+ int protocol;
+
+ if (skb->ip_summed != CHECKSUM_PARTIAL)
+ return 0;
+
+ switch (skb->protocol) {
+ case cpu_to_be16(ETH_P_IP):
+ protocol = ip_hdr(skb)->protocol;
+ break;
+ case cpu_to_be16(ETH_P_IPV6):
+ protocol = ipv6_hdr(skb)->nexthdr;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ switch (protocol) {
+ case IPPROTO_TCP:
+ d->dma.d0 |= (2 << DMA_CFG_DESC_TX_0_L4_TYPE_POS);
+ /* L4 header len: TCP header length */
+ d->dma.d0 |=
+ (tcp_hdrlen(skb) & DMA_CFG_DESC_TX_0_L4_LENGTH_MSK);
+ break;
+ case IPPROTO_UDP:
+ /* L4 header len: UDP header length */
+ d->dma.d0 |=
+ (sizeof(struct udphdr) & DMA_CFG_DESC_TX_0_L4_LENGTH_MSK);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ d->dma.ip_length = skb_network_header_len(skb);
+ d->dma.b11 = ETH_HLEN; /* MAC header length */
+ d->dma.b11 |= BIT(DMA_CFG_DESC_TX_OFFLOAD_CFG_L3T_IPV4_POS);
+ /* Enable TCP/UDP checksum */
+ d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_TCP_UDP_CHECKSUM_EN_POS);
+ /* Calculate pseudo-header */
+ d->dma.d0 |= BIT(DMA_CFG_DESC_TX_0_PSEUDO_HEADER_CALC_EN_POS);
+
+ return 0;
+}
+
static int wil_tx_vring(struct wil6210_priv *wil, struct vring *vring,
struct sk_buff *skb)
{
@@ -655,7 +720,7 @@ static int wil_tx_vring(struct wil6210_priv *wil, struct vring *vring,
u32 swhead = vring->swhead;
int avail = wil_vring_avail_tx(vring);
int nr_frags = skb_shinfo(skb)->nr_frags;
- uint f;
+ uint f = 0;
int vring_index = vring - wil->vring_tx;
uint i = swhead;
dma_addr_t pa;
@@ -686,13 +751,20 @@ static int wil_tx_vring(struct wil6210_priv *wil, struct vring *vring,
return -EINVAL;
/* 1-st segment */
wil_tx_desc_map(d, pa, skb_headlen(skb), vring_index);
+ /* Process TCP/UDP checksum offloading */
+ if (wil_tx_desc_offload_cksum_set(wil, d, skb)) {
+ wil_err(wil, "VRING #%d Failed to set cksum, drop packet\n",
+ vring_index);
+ goto dma_error;
+ }
+
d->mac.d[2] |= ((nr_frags + 1) <<
MAC_CFG_DESC_TX_2_NUM_OF_DESCRIPTORS_POS);
if (nr_frags)
*_d = *d;

/* middle segments */
- for (f = 0; f < nr_frags; f++) {
+ for (; f < nr_frags; f++) {
const struct skb_frag_struct *frag =
&skb_shinfo(skb)->frags[f];
int len = skb_frag_size(frag);
diff --git a/drivers/net/wireless/ath/wil6210/txrx.h b/drivers/net/wireless/ath/wil6210/txrx.h
index 859aea6..b382827 100644
--- a/drivers/net/wireless/ath/wil6210/txrx.h
+++ b/drivers/net/wireless/ath/wil6210/txrx.h
@@ -235,7 +235,16 @@ struct vring_tx_mac {

#define DMA_CFG_DESC_TX_0_L4_TYPE_POS 30
#define DMA_CFG_DESC_TX_0_L4_TYPE_LEN 2
-#define DMA_CFG_DESC_TX_0_L4_TYPE_MSK 0xC0000000
+#define DMA_CFG_DESC_TX_0_L4_TYPE_MSK 0xC0000000 /* L4 type: 0-UDP, 2-TCP */
+
+
+#define DMA_CFG_DESC_TX_OFFLOAD_CFG_MAC_LEN_POS 0
+#define DMA_CFG_DESC_TX_OFFLOAD_CFG_MAC_LEN_LEN 7
+#define DMA_CFG_DESC_TX_OFFLOAD_CFG_MAC_LEN_MSK 0x7F /* MAC hdr len */
+
+#define DMA_CFG_DESC_TX_OFFLOAD_CFG_L3T_IPV4_POS 7
+#define DMA_CFG_DESC_TX_OFFLOAD_CFG_L3T_IPV4_LEN 1
+#define DMA_CFG_DESC_TX_OFFLOAD_CFG_L3T_IPV4_MSK 0x80 /* 1-IPv4, 0-IPv6 */


#define TX_DMA_STATUS_DU BIT(0)
@@ -334,8 +343,17 @@ struct vring_rx_mac {

#define RX_DMA_D0_CMD_DMA_IT BIT(10)

+/* Error field, offload bits */
+#define RX_DMA_ERROR_L3_ERR BIT(4)
+#define RX_DMA_ERROR_L4_ERR BIT(5)
+
+
+/* Status field */
#define RX_DMA_STATUS_DU BIT(0)
#define RX_DMA_STATUS_ERROR BIT(2)
+
+#define RX_DMA_STATUS_L3_IDENT BIT(4)
+#define RX_DMA_STATUS_L4_IDENT BIT(5)
#define RX_DMA_STATUS_PHY_INFO BIT(6)

struct vring_rx_dma {
diff --git a/drivers/net/wireless/ath/wil6210/wmi.c b/drivers/net/wireless/ath/wil6210/wmi.c
index a62511a..5220f15 100644
--- a/drivers/net/wireless/ath/wil6210/wmi.c
+++ b/drivers/net/wireless/ath/wil6210/wmi.c
@@ -924,6 +924,12 @@ int wmi_rx_chain_add(struct wil6210_priv *wil, struct vring *vring)
cmd.sniffer_cfg.phy_support =
cpu_to_le32((wil->monitor_flags & MONITOR_FLAG_CONTROL)
? WMI_SNIFFER_CP : WMI_SNIFFER_DP);
+ } else {
+ /* Initialize offload (in non-sniffer mode).
+ * Linux IP stack always calculates IP checksum
+ * HW always calculate TCP/UDP checksum
+ */
+ cmd.l3_l4_ctrl |= (1 << L3_L4_CTRL_TCPIP_CHECKSUM_EN_POS);
}
/* typical time for secure PCP is 840ms */
rc = wmi_call(wil, WMI_CFG_RX_CHAIN_CMDID, &cmd, sizeof(cmd),
--
1.8.1.2