iwlwifi: mvm: enable TCP/UDP checksum support for 9000 family
authorSara Sharon <sara.sharon@intel.com>
Thu, 10 Mar 2016 15:40:56 +0000 (17:40 +0200)
committerEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Wed, 30 Mar 2016 13:24:49 +0000 (16:24 +0300)
Declare and enable support of RX and TX checksum for 9000 family.
Configure offload_assist in the TX cmd accordingly to support
TX csum.

Signed-off-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
drivers/net/wireless/intel/iwlwifi/iwl-9000.c
drivers/net/wireless/intel/iwlwifi/iwl-config.h
drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
drivers/net/wireless/intel/iwlwifi/mvm/tx.c

index 277396a..1f25ba6 100644 (file)
@@ -137,6 +137,7 @@ static const struct iwl_tt_params iwl9000_tt_params = {
        .dccm2_len = IWL9000_DCCM2_LEN,                                 \
        .smem_offset = IWL9000_SMEM_OFFSET,                             \
        .smem_len = IWL9000_SMEM_LEN,                                   \
+       .features = IWL_TX_CSUM_NETIF_FLAGS | NETIF_F_RXCSUM,           \
        .thermal_params = &iwl9000_tt_params,                           \
        .apmg_not_supported = true,                                     \
        .mq_rx_supported = true,                                        \
index 8cbd248..b002557 100644 (file)
@@ -131,6 +131,8 @@ enum iwl_led_mode {
 #define IWL_MAX_WD_TIMEOUT     120000
 
 #define IWL_DEFAULT_MAX_TX_POWER 22
+#define IWL_TX_CSUM_NETIF_FLAGS (NETIF_F_IPV6_CSUM | NETIF_F_IP_CSUM |\
+                                NETIF_F_TSO | NETIF_F_TSO6)
 
 /* Antenna presence definitions */
 #define        ANT_NONE        0x0
index 115d7aa..4f5ec49 100644 (file)
@@ -665,12 +665,13 @@ int iwl_mvm_mac_setup_register(struct iwl_mvm *mvm)
        }
 
        hw->netdev_features |= mvm->cfg->features;
-       if (!iwl_mvm_is_csum_supported(mvm))
-               hw->netdev_features &= ~NETIF_F_RXCSUM;
-
-       if (IWL_MVM_SW_TX_CSUM_OFFLOAD)
-               hw->netdev_features |= NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM |
-                       NETIF_F_TSO | NETIF_F_TSO6;
+       if (!iwl_mvm_is_csum_supported(mvm)) {
+               hw->netdev_features &= ~(IWL_TX_CSUM_NETIF_FLAGS |
+                                        NETIF_F_RXCSUM);
+               /* We may support SW TX CSUM */
+               if (IWL_MVM_SW_TX_CSUM_OFFLOAD)
+                       hw->netdev_features |= IWL_TX_CSUM_NETIF_FLAGS;
+       }
 
        ret = ieee80211_register_hw(mvm->hw);
        if (ret)
index 24cff98..efb9b98 100644 (file)
@@ -67,6 +67,7 @@
 #include <linux/etherdevice.h>
 #include <linux/tcp.h>
 #include <net/ip.h>
+#include <net/ipv6.h>
 
 #include "iwl-trans.h"
 #include "iwl-eeprom-parse.h"
@@ -98,6 +99,111 @@ iwl_mvm_bar_check_trigger(struct iwl_mvm *mvm, const u8 *addr,
                                    addr, tid, ssn);
 }
 
+#define OPT_HDR(type, skb, off) \
+       (type *)(skb_network_header(skb) + (off))
+
+static void iwl_mvm_tx_csum(struct iwl_mvm *mvm, struct sk_buff *skb,
+                           struct ieee80211_hdr *hdr,
+                           struct ieee80211_tx_info *info,
+                           struct iwl_tx_cmd *tx_cmd)
+{
+#if IS_ENABLED(CONFIG_INET)
+       u16 mh_len = ieee80211_hdrlen(hdr->frame_control);
+       u16 offload_assist = le16_to_cpu(tx_cmd->offload_assist);
+       u8 protocol = 0;
+
+       /*
+        * Do not compute checksum if already computed or if transport will
+        * compute it
+        */
+       if (skb->ip_summed != CHECKSUM_PARTIAL || IWL_MVM_SW_TX_CSUM_OFFLOAD)
+               return;
+
+       /* We do not expect to be requested to csum stuff we do not support */
+       if (WARN_ONCE(!(mvm->hw->netdev_features & IWL_TX_CSUM_NETIF_FLAGS) ||
+                     (skb->protocol != htons(ETH_P_IP) &&
+                      skb->protocol != htons(ETH_P_IPV6)),
+                     "No support for requested checksum\n")) {
+               skb_checksum_help(skb);
+               return;
+       }
+
+       if (skb->protocol == htons(ETH_P_IP)) {
+               protocol = ip_hdr(skb)->protocol;
+       } else {
+#if IS_ENABLED(CONFIG_IPV6)
+               struct ipv6hdr *ipv6h =
+                       (struct ipv6hdr *)skb_network_header(skb);
+               unsigned int off = sizeof(*ipv6h);
+
+               protocol = ipv6h->nexthdr;
+               while (protocol != NEXTHDR_NONE && ipv6_ext_hdr(protocol)) {
+                       /* only supported extension headers */
+                       if (protocol != NEXTHDR_ROUTING &&
+                           protocol != NEXTHDR_HOP &&
+                           protocol != NEXTHDR_DEST &&
+                           protocol != NEXTHDR_FRAGMENT) {
+                               skb_checksum_help(skb);
+                               return;
+                       }
+
+                       if (protocol == NEXTHDR_FRAGMENT) {
+                               struct frag_hdr *hp =
+                                       OPT_HDR(struct frag_hdr, skb, off);
+
+                               protocol = hp->nexthdr;
+                               off += sizeof(struct frag_hdr);
+                       } else {
+                               struct ipv6_opt_hdr *hp =
+                                       OPT_HDR(struct ipv6_opt_hdr, skb, off);
+
+                               protocol = hp->nexthdr;
+                               off += ipv6_optlen(hp);
+                       }
+               }
+               /* if we get here - protocol now should be TCP/UDP */
+#endif
+       }
+
+       if (protocol != IPPROTO_TCP && protocol != IPPROTO_UDP) {
+               WARN_ON_ONCE(1);
+               skb_checksum_help(skb);
+               return;
+       }
+
+       /* enable L4 csum */
+       offload_assist |= BIT(TX_CMD_OFFLD_L4_EN);
+
+       /*
+        * Set offset to IP header (snap).
+        * We don't support tunneling so no need to take care of inner header.
+        * Size is in words.
+        */
+       offload_assist |= (4 << TX_CMD_OFFLD_IP_HDR);
+
+       /* Do IPv4 csum for AMSDU only (no IP csum for Ipv6) */
+       if (skb->protocol == htons(ETH_P_IP) &&
+           (offload_assist & BIT(TX_CMD_OFFLD_AMSDU))) {
+               ip_hdr(skb)->check = 0;
+               offload_assist |= BIT(TX_CMD_OFFLD_L3_EN);
+       }
+
+       /* reset UDP/TCP header csum */
+       if (protocol == IPPROTO_TCP)
+               tcp_hdr(skb)->check = 0;
+       else
+               udp_hdr(skb)->check = 0;
+
+       /* mac header len should include IV, size is in words */
+       if (info->control.hw_key)
+               mh_len += info->control.hw_key->iv_len;
+       mh_len /= 2;
+       offload_assist |= mh_len << TX_CMD_OFFLD_MH_SIZE;
+
+       tx_cmd->offload_assist = cpu_to_le16(offload_assist);
+#endif
+}
+
 /*
  * Sets most of the Tx cmd's fields
  */
@@ -196,6 +302,8 @@ void iwl_mvm_set_tx_cmd(struct iwl_mvm *mvm, struct sk_buff *skb,
        if (ieee80211_hdrlen(fc) % 4 &&
            !(tx_cmd->offload_assist & cpu_to_le16(BIT(TX_CMD_OFFLD_AMSDU))))
                tx_cmd->offload_assist |= cpu_to_le16(BIT(TX_CMD_OFFLD_PAD));
+
+       iwl_mvm_tx_csum(mvm, skb, hdr, info, tx_cmd);
 }
 
 /*
@@ -466,6 +574,7 @@ static int iwl_mvm_tx_tso(struct iwl_mvm *mvm, struct sk_buff *skb,
        u16 ip_base_id = ipv4 ? ntohs(ip_hdr(skb)->id) : 0;
        u16 amsdu_add, snap_ip_tcp, pad, i = 0;
        unsigned int dbg_max_amsdu_len;
+       netdev_features_t netdev_features = NETIF_F_CSUM_MASK | NETIF_F_SG;
        u8 *qc, tid, txf;
 
        snap_ip_tcp = 8 + skb_transport_header(skb) - skb_network_header(skb) +
@@ -485,6 +594,19 @@ static int iwl_mvm_tx_tso(struct iwl_mvm *mvm, struct sk_buff *skb,
        }
 
        /*
+        * Do not build AMSDU for IPv6 with extension headers.
+        * ask stack to segment and checkum the generated MPDUs for us.
+        */
+       if (skb->protocol == htons(ETH_P_IPV6) &&
+           ((struct ipv6hdr *)skb_network_header(skb))->nexthdr !=
+           IPPROTO_TCP) {
+               num_subframes = 1;
+               pad = 0;
+               netdev_features &= ~NETIF_F_CSUM_MASK;
+               goto segment;
+       }
+
+       /*
         * No need to lock amsdu_in_ampdu_allowed since it can't be modified
         * during an BA session.
         */
@@ -577,7 +699,7 @@ segment:
        skb_shinfo(skb)->gso_size = num_subframes * mss;
        memcpy(cb, skb->cb, sizeof(cb));
 
-       next = skb_gso_segment(skb, NETIF_F_CSUM_MASK | NETIF_F_SG);
+       next = skb_gso_segment(skb, netdev_features);
        skb_shinfo(skb)->gso_size = mss;
        if (WARN_ON_ONCE(IS_ERR(next)))
                return -EINVAL;