wl12xx: Add support to RX packets payload alignment

In case of QoS packets the packet payload isn't aligned to
4 bytes. In that case the mac80211 layer take care of that
via memmove() in ieee80211_deliver_skb().
Add support of copy packets from aggregation buffer to the
skbs with packet payload aligned care. In case of QoS packets
copy the packets in offset of 2 bytes guarantee payload aligned
to 4 bytes.

Signed-off-by: Shahar Levi <shahar_levi@ti.com>
Signed-off-by: Luciano Coelho <coelho@ti.com>

diff --git a/drivers/net/wireless/wl12xx/rx.c b/drivers/net/wireless/wl12xx/rx.c
index 0450fb49dbb198c117f521f4e379b645cb85b029..46f4af6ca72367413e75e9869ca8d849b540e354 100644 (file)
--- a/drivers/net/wireless/wl12xx/rx.c
+++ b/drivers/net/wireless/wl12xx/rx.c
@@ -38,12 +38,20 @@ static u8 wl1271_rx_get_mem_block(struct wl1271_fw_common_status *status,
 }
 
 static u32 wl1271_rx_get_buf_size(struct wl1271_fw_common_status *status,
-                                u32 drv_rx_counter)
+                                 u32 drv_rx_counter)
 {
        return (le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]) &
                RX_BUF_SIZE_MASK) >> RX_BUF_SIZE_SHIFT_DIV;
 }
 
+static bool wl1271_rx_get_unaligned(struct wl1271_fw_common_status *status,
+                                   u32 drv_rx_counter)
+{
+       /* Convert the value to bool */
+       return !!(le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]) &
+               RX_BUF_UNALIGNED_PAYLOAD);
+}
+
 static void wl1271_rx_status(struct wl1271 *wl,
                             struct wl1271_rx_descriptor *desc,
                             struct ieee80211_rx_status *status,
@@ -89,7 +97,8 @@ static void wl1271_rx_status(struct wl1271 *wl,
        }
 }
 
-static int wl1271_rx_handle_data(struct wl1271 *wl, u8 *data, u32 length)
+static int wl1271_rx_handle_data(struct wl1271 *wl, u8 *data, u32 length,
+                                bool unaligned)
 {
        struct wl1271_rx_descriptor *desc;
        struct sk_buff *skb;
@@ -97,6 +106,7 @@ static int wl1271_rx_handle_data(struct wl1271 *wl, u8 *data, u32 length)
        u8 *buf;
        u8 beacon = 0;
        u8 is_data = 0;
+       u8 reserved = unaligned ? NET_IP_ALIGN : 0;
 
        /*
         * In PLT mode we seem to get frames and mac80211 warns about them,
@@ -131,17 +141,25 @@ static int wl1271_rx_handle_data(struct wl1271 *wl, u8 *data, u32 length)
                return -EINVAL;
        }
 
-       skb = __dev_alloc_skb(length, GFP_KERNEL);
+       /* skb length not included rx descriptor */
+       skb = __dev_alloc_skb(length + reserved - sizeof(*desc), GFP_KERNEL);
        if (!skb) {
                wl1271_error("Couldn't allocate RX frame");
                return -ENOMEM;
        }
 
-       buf = skb_put(skb, length);
-       memcpy(buf, data, length);
+       /* reserve the unaligned payload(if any) */
+       skb_reserve(skb, reserved);
+
+       buf = skb_put(skb, length - sizeof(*desc));
 
-       /* now we pull the descriptor out of the buffer */
-       skb_pull(skb, sizeof(*desc));
+       /*
+        * Copy packets from aggregation buffer to the skbs without rx
+        * descriptor and with packet payload aligned care. In case of unaligned
+        * packets copy the packets in offset of 2 bytes guarantee IP header
+        * payload aligned to 4 bytes.
+        */
+       memcpy(buf, data + sizeof(*desc), length - sizeof(*desc));
 
        hdr = (struct ieee80211_hdr *)skb->data;
        if (ieee80211_is_beacon(hdr->frame_control))
@@ -175,6 +193,7 @@ void wl1271_rx(struct wl1271 *wl, struct wl1271_fw_common_status *status)
        u32 pkt_offset;
        bool is_ap = (wl->bss_type == BSS_TYPE_AP_BSS);
        bool had_data = false;
+       bool unaligned = false;
 
        while (drv_rx_counter != fw_rx_counter) {
                buf_size = 0;
@@ -222,6 +241,10 @@ void wl1271_rx(struct wl1271 *wl, struct wl1271_fw_common_status *status)
                while (pkt_offset < buf_size) {
                        pkt_length = wl1271_rx_get_buf_size(status,
                                        drv_rx_counter);
+
+                       unaligned = wl1271_rx_get_unaligned(status,
+                                       drv_rx_counter);
+
                        /*
                         * the handle data call can only fail in memory-outage
                         * conditions, in that case the received frame will just
@@ -229,7 +252,7 @@ void wl1271_rx(struct wl1271 *wl, struct wl1271_fw_common_status *status)
                         */
                        if (wl1271_rx_handle_data(wl,
                                                  wl->aggr_buf + pkt_offset,
-                                                 pkt_length) == 1)
+                                                 pkt_length, unaligned) == 1)
                                had_data = true;
 
                        wl->rx_counter++;

diff --git a/drivers/net/wireless/wl12xx/rx.h b/drivers/net/wireless/wl12xx/rx.h
index c88e3fa1d6039c24aec78336117a00b811f1255c..0325b9de612e2874c71eba3a156222641542951b 100644 (file)
--- a/drivers/net/wireless/wl12xx/rx.h
+++ b/drivers/net/wireless/wl12xx/rx.h
@@ -93,9 +93,11 @@
 #define WL1271_RX_DESC_MIC_FAIL         0x02
 #define WL1271_RX_DESC_DRIVER_RX_Q_FAIL 0x03
 
-#define RX_MEM_BLOCK_MASK     0xFF
-#define RX_BUF_SIZE_MASK      0xFFF00
-#define RX_BUF_SIZE_SHIFT_DIV 6
+#define RX_MEM_BLOCK_MASK            0xFF
+#define RX_BUF_SIZE_MASK             0xFFF00
+#define RX_BUF_SIZE_SHIFT_DIV        6
+/* If set, the start of IP payload is not 4 bytes aligned */
+#define RX_BUF_UNALIGNED_PAYLOAD     BIT(20)
 
 enum {
        WL12XX_RX_CLASS_UNKNOWN,