qcacld: Classify DHCP frames as high priority to avoid frame drop

For SDIO 2.0, the maximum UL is 50-60 Mbps. But, when high UDP
traffic (300Mbps) is run on a p2p connection in SDIO 2.0, we are
hitting low rsrc threshold and some queued frames are getting
dropped to provide enough tx descriptors for new frames which may
be of higher priority. This is as per our current implementation.

Now, when DHCP renewal happens during the above mentioned
scenario, TID of multicast packets are set to low priority mcast,
bcast category and TID of unicast DHCP packets are received with
TID as best effort

When frame drop happens, the above DHCP frames are dropped
because of lower priority. Hence DHCP renewal fails, P2P
connection is terminated. This is fixed by marking the DHCP
frames as high priority.

Change-Id: I9318d444e311ae2041b325c404734bb292cd5b43
CRs-Fixed: 775540

4 files changed, 62 insertions, 3 deletions

diff --git a/CORE/CLD_TXRX/TXRX/ol_tx_classify.c b/CORE/CLD_TXRX/TXRX/ol_tx_classify.c
index 0c523d90d42b..bc9d5652ce5e 100644
--- a/CORE/CLD_TXRX/TXRX/ol_tx_classify.c
+++ b/CORE/CLD_TXRX/TXRX/ol_tx_classify.c
@@ -94,6 +94,9 @@ ol_tx_classify_htt2_frm(
 #define OL_TX_CLASSIFY_HTT2_EXTENSION(vdev, netbuf, msdu_info)      /* no-op */
 #endif /* QCA_TX_HTT2_SUPPORT */
 
+/* DHCP go with voice priority: WMM_AC_TO_TID1(WMM_AC_VO);*/
+#define TX_DHCP_TID  6
+
 /* EAPOL go with voice priority: WMM_AC_TO_TID1(WMM_AC_VO);*/
 #define TX_EAPOL_TID  6
 
@@ -275,9 +278,15 @@ ol_tx_tid(
         tx_msdu_info->htt.info.l2_hdr_type = htt_pkt_type_ethernet;
 
         ol_tx_set_ether_type(datap, tx_msdu_info);
-        tid = tx_msdu_info->htt.info.ext_tid == ADF_NBUF_TX_EXT_TID_INVALID ?
-            ol_tx_tid_by_ether_type(datap, tx_msdu_info) :
-            tx_msdu_info->htt.info.ext_tid;
+        if (A_STATUS_OK == adf_nbuf_is_dhcp_pkt(tx_nbuf)) {
+            /* DHCP frame to go with voice priority */
+            tid = TX_DHCP_TID;
+        } else {
+            tid =
+                tx_msdu_info->htt.info.ext_tid == ADF_NBUF_TX_EXT_TID_INVALID ?
+                ol_tx_tid_by_ether_type(datap, tx_msdu_info) :
+                tx_msdu_info->htt.info.ext_tid;
+        }
     } else if (pdev->frame_format == wlan_frm_fmt_native_wifi) {
         struct llc_snap_hdr_t *llc;
 
@@ -343,6 +352,11 @@ ol_tx_classify(
                     vdev->mac_addr.raw[2], vdev->mac_addr.raw[3],
                     vdev->mac_addr.raw[4], vdev->mac_addr.raw[5]);
                 return NULL; /* error */
+            } else if (A_STATUS_OK ==
+                            adf_nbuf_is_dhcp_pkt(tx_nbuf)) {
+                /* DHCP frame to go with voice priority */
+                txq = &peer->txqs[TX_DHCP_TID];
+                tx_msdu_info->htt.info.ext_tid = TX_DHCP_TID;
             }
             /*
              * The following line assumes each peer object has a single ID.
diff --git a/CORE/SERVICES/COMMON/adf/adf_nbuf.c b/CORE/SERVICES/COMMON/adf/adf_nbuf.c
index bf8d95264500..b5a0cacd5517 100644
--- a/CORE/SERVICES/COMMON/adf/adf_nbuf.c
+++ b/CORE/SERVICES/COMMON/adf/adf_nbuf.c
@@ -32,6 +32,7 @@
 #include <linux/module.h>
 #include <adf_os_types.h>
 #include <adf_nbuf.h>
+#include <adf_os_io.h>
 
 adf_nbuf_trace_update_t  trace_update_cb = NULL;
 
@@ -383,6 +384,30 @@ __adf_nbuf_reg_trace_cb(adf_nbuf_trace_update_t cb_func_ptr)
    return;
 }
 
+a_status_t
+__adf_nbuf_is_dhcp_pkt(struct sk_buff *skb)
+{
+   a_uint16_t    SPort;
+   a_uint16_t    DPort;
+
+    SPort = (a_uint16_t)(*(a_uint16_t *)(skb->data + ADF_NBUF_TRAC_IPV4_OFFSET +
+                                     ADF_NBUF_TRAC_IPV4_HEADER_SIZE));
+    DPort = (a_uint16_t)(*(a_uint16_t *)(skb->data + ADF_NBUF_TRAC_IPV4_OFFSET +
+                                     ADF_NBUF_TRAC_IPV4_HEADER_SIZE + sizeof(a_uint16_t)));
+
+    if (((ADF_NBUF_TRAC_DHCP_SRV_PORT == adf_os_cpu_to_be16(SPort)) &&
+       (ADF_NBUF_TRAC_DHCP_CLI_PORT == adf_os_cpu_to_be16(DPort))) ||
+       ((ADF_NBUF_TRAC_DHCP_CLI_PORT == adf_os_cpu_to_be16(SPort)) &&
+       (ADF_NBUF_TRAC_DHCP_SRV_PORT == adf_os_cpu_to_be16(DPort))))
+    {
+        return A_STATUS_OK;
+    }
+    else
+    {
+        return A_STATUS_FAILED;
+    }
+}
+
 #ifdef QCA_PKT_PROTO_TRACE
 void
 __adf_nbuf_trace_update(struct sk_buff *buf, char *event_string)
@@ -449,3 +474,4 @@ EXPORT_SYMBOL(__adf_nbuf_get_tid);
 EXPORT_SYMBOL(__adf_nbuf_set_tid);
 EXPORT_SYMBOL(__adf_nbuf_get_exemption_type);
 EXPORT_SYMBOL(__adf_nbuf_dmamap_set_cb);
+EXPORT_SYMBOL(__adf_nbuf_is_dhcp_pkt);
diff --git a/CORE/SERVICES/COMMON/adf/adf_nbuf.h b/CORE/SERVICES/COMMON/adf/adf_nbuf.h
index abec0928b53d..602e7d12e54c 100644
--- a/CORE/SERVICES/COMMON/adf/adf_nbuf.h
+++ b/CORE/SERVICES/COMMON/adf/adf_nbuf.h
@@ -54,6 +54,11 @@
 #define NBUF_PKT_TRAC_MAX_STRING   12
 #define NBUF_PKT_TRAC_PROTO_STRING 4
 
+#define ADF_NBUF_TRAC_IPV4_OFFSET       14
+#define ADF_NBUF_TRAC_IPV4_HEADER_SIZE  20
+#define ADF_NBUF_TRAC_DHCP_SRV_PORT     67
+#define ADF_NBUF_TRAC_DHCP_CLI_PORT     68
+
 /**
  * @brief Platform indepedent packet abstraction
  */
@@ -1133,4 +1138,17 @@ adf_nbuf_get_tx_parallel_dnload_frm(adf_nbuf_t buf)
    return __adf_nbuf_get_tx_htt2_frm(buf);
 }
 
+/**
+ * @brief this will return if the skb data is a dhcp packet or not
+ *
+ * @param[in] buf       buffer
+ *
+ * @return A_STATUS_OK if packet is DHCP packet
+ */
+static inline a_status_t
+adf_nbuf_is_dhcp_pkt(adf_nbuf_t buf)
+{
+    return (__adf_nbuf_is_dhcp_pkt(buf));
+}
+
 #endif
diff --git a/CORE/SERVICES/COMMON/adf/linux/adf_nbuf_pvt.h b/CORE/SERVICES/COMMON/adf/linux/adf_nbuf_pvt.h
index fa168f4d40b6..bc51123a2d67 100644
--- a/CORE/SERVICES/COMMON/adf/linux/adf_nbuf_pvt.h
+++ b/CORE/SERVICES/COMMON/adf/linux/adf_nbuf_pvt.h
@@ -264,6 +264,7 @@ void            __adf_nbuf_dmamap_info(__adf_os_dma_map_t bmap, adf_os_dmamap_in
 void            __adf_nbuf_frag_info(struct sk_buff *skb, adf_os_sglist_t  *sg);
 void            __adf_nbuf_dmamap_set_cb(__adf_os_dma_map_t dmap, void *cb, void *arg);
 void            __adf_nbuf_reg_trace_cb(adf_nbuf_trace_update_t cb_func_ptr);
+a_status_t      __adf_nbuf_is_dhcp_pkt(struct sk_buff *skb);
 
 #ifdef QCA_PKT_PROTO_TRACE
 void