wl1271: Support firmware RX packet aggregation

Instead of retrieving one packet at a time from the firmware, try to
retrieve all available packets at once.
This optimization decreases the number of transactions, which saves
CPU cycles and increases network throughput.

Signed-off-by: Ido Yariv <ido@wizery.com>
Tested-by: Juuso Oikarinen <juuso.oikarinen@nokia.com>
Signed-off-by: Luciano Coelho <luciano.coelho@nokia.com>

3 files changed, 66 insertions, 17 deletions

diff --git a/drivers/net/wireless/wl12xx/wl1271.h b/drivers/net/wireless/wl12xx/wl1271.h
index 779b130fdb3..8a4cd763e5a 100644
--- a/drivers/net/wireless/wl12xx/wl1271.h
+++ b/drivers/net/wireless/wl12xx/wl1271.h
@@ -130,6 +130,8 @@ enum {
 
 #define ACX_TX_DESCRIPTORS         32
 
+#define WL1271_AGGR_BUFFER_SIZE (4 * PAGE_SIZE)
+
 enum wl1271_state {
         WL1271_STATE_OFF,
         WL1271_STATE_ON,
@@ -408,6 +410,9 @@ struct wl1271 {
         /* Rx memory pool address */
         struct wl1271_rx_mem_pool_addr rx_mem_pool_addr;
 
+        /* Intermediate buffer, used for packet aggregation */
+        u8 *aggr_buf;
+
         /* The target interrupt mask */
         struct work_struct irq_work;
 
diff --git a/drivers/net/wireless/wl12xx/wl1271_main.c b/drivers/net/wireless/wl12xx/wl1271_main.c
index cb18f22bbc5..8071da10dbc 100644
--- a/drivers/net/wireless/wl12xx/wl1271_main.c
+++ b/drivers/net/wireless/wl12xx/wl1271_main.c
@@ -2459,6 +2459,7 @@ struct ieee80211_hw *wl1271_alloc_hw(void)
         struct platform_device *plat_dev = NULL;
         struct wl1271 *wl;
         int i, ret;
+        unsigned int order;
 
         hw = ieee80211_alloc_hw(sizeof(*wl), &wl1271_ops);
         if (!hw) {
@@ -2517,11 +2518,18 @@ struct ieee80211_hw *wl1271_alloc_hw(void)
 
         wl1271_debugfs_init(wl);
 
+        order = get_order(WL1271_AGGR_BUFFER_SIZE);
+        wl->aggr_buf = (u8 *)__get_free_pages(GFP_KERNEL, order);
+        if (!wl->aggr_buf) {
+                ret = -ENOMEM;
+                goto err_hw;
+        }
+
         /* Register platform device */
         ret = platform_device_register(wl->plat_dev);
         if (ret) {
                 wl1271_error("couldn't register platform device");
-                goto err_hw;
+                goto err_aggr;
         }
         dev_set_drvdata(&wl->plat_dev->dev, wl);
 
@@ -2547,6 +2555,9 @@ err_bt_coex_state:
 err_platform:
         platform_device_unregister(wl->plat_dev);
 
+err_aggr:
+        free_pages((unsigned long)wl->aggr_buf, order);
+
 err_hw:
         wl1271_debugfs_exit(wl);
         kfree(plat_dev);
@@ -2563,6 +2574,8 @@ EXPORT_SYMBOL_GPL(wl1271_alloc_hw);
 int wl1271_free_hw(struct wl1271 *wl)
 {
         platform_device_unregister(wl->plat_dev);
+        free_pages((unsigned long)wl->aggr_buf,
+                        get_order(WL1271_AGGR_BUFFER_SIZE));
         kfree(wl->plat_dev);
 
         wl1271_debugfs_exit(wl);
diff --git a/drivers/net/wireless/wl12xx/wl1271_rx.c b/drivers/net/wireless/wl12xx/wl1271_rx.c
index 94da5dd7723..bea133b6e48 100644
--- a/drivers/net/wireless/wl12xx/wl1271_rx.c
+++ b/drivers/net/wireless/wl12xx/wl1271_rx.c
@@ -74,7 +74,7 @@ static void wl1271_rx_status(struct wl1271 *wl,
         }
 }
 
-static void wl1271_rx_handle_data(struct wl1271 *wl, u32 length)
+static int wl1271_rx_handle_data(struct wl1271 *wl, u8 *data, u32 length)
 {
         struct wl1271_rx_descriptor *desc;
         struct sk_buff *skb;
@@ -87,16 +87,16 @@ static void wl1271_rx_handle_data(struct wl1271 *wl, u32 length)
          * workaround this by not retrieving them at all.
          */
         if (unlikely(wl->state == WL1271_STATE_PLT))
-                return;
+                return -EINVAL;
 
         skb = __dev_alloc_skb(length, GFP_KERNEL);
         if (!skb) {
                 wl1271_error("Couldn't allocate RX frame");
-                return;
+                return -ENOMEM;
         }
 
         buf = skb_put(skb, length);
-        wl1271_read(wl, WL1271_SLV_MEM_DATA, buf, length, true);
+        memcpy(buf, data, length);
 
         /* the data read starts with the descriptor */
         desc = (struct wl1271_rx_descriptor *) buf;
@@ -116,6 +116,8 @@ static void wl1271_rx_handle_data(struct wl1271 *wl, u32 length)
         skb_trim(skb, skb->len - desc->pad_len);
 
         ieee80211_rx_ni(wl->hw, skb);
+
+        return 0;
 }
 
 void wl1271_rx(struct wl1271 *wl, struct wl1271_fw_status *status)
@@ -124,31 +126,60 @@ void wl1271_rx(struct wl1271 *wl, struct wl1271_fw_status *status)
         u32 buf_size;
         u32 fw_rx_counter  = status->fw_rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
         u32 drv_rx_counter = wl->rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
+        u32 rx_counter;
         u32 mem_block;
+        u32 pkt_length;
+        u32 pkt_offset;
 
         while (drv_rx_counter != fw_rx_counter) {
-                mem_block = wl1271_rx_get_mem_block(status, drv_rx_counter);
-                buf_size = wl1271_rx_get_buf_size(status, drv_rx_counter);
+                buf_size = 0;
+                rx_counter = drv_rx_counter;
+                while (rx_counter != fw_rx_counter) {
+                        pkt_length = wl1271_rx_get_buf_size(status, rx_counter);
+                        if (buf_size + pkt_length > WL1271_AGGR_BUFFER_SIZE)
+                                break;
+                        buf_size += pkt_length;
+                        rx_counter++;
+                        rx_counter &= NUM_RX_PKT_DESC_MOD_MASK;
+                }
 
                 if (buf_size == 0) {
                         wl1271_warning("received empty data");
                         break;
                 }
 
+                /*
+                 * Choose the block we want to read
+                 * For aggregated packets, only the first memory block should
+                 * be retrieved. The FW takes care of the rest.
+                 */
+                mem_block = wl1271_rx_get_mem_block(status, drv_rx_counter);
                 wl->rx_mem_pool_addr.addr = (mem_block << 8) +
                         le32_to_cpu(wl_mem_map->packet_memory_pool_start);
                 wl->rx_mem_pool_addr.addr_extra =
                         wl->rx_mem_pool_addr.addr + 4;
-
-                /* Choose the block we want to read */
                 wl1271_write(wl, WL1271_SLV_REG_DATA, &wl->rx_mem_pool_addr,
-                             sizeof(wl->rx_mem_pool_addr), false);
-
-                wl1271_rx_handle_data(wl, buf_size);
-
-                wl->rx_counter++;
-                drv_rx_counter = wl->rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
+                                sizeof(wl->rx_mem_pool_addr), false);
+
+                /* Read all available packets at once */
+                wl1271_read(wl, WL1271_SLV_MEM_DATA, wl->aggr_buf,
+                                buf_size, true);
+
+                /* Split data into separate packets */
+                pkt_offset = 0;
+                while (pkt_offset < buf_size) {
+                        pkt_length = wl1271_rx_get_buf_size(status,
+                                        drv_rx_counter);
+                        if (wl1271_rx_handle_data(wl,
+                                        wl->aggr_buf + pkt_offset,
+                                        pkt_length) < 0)
+                                break;
+                        wl->rx_counter++;
+                        drv_rx_counter++;
+                        drv_rx_counter &= NUM_RX_PKT_DESC_MOD_MASK;
+                        pkt_offset += pkt_length;
+                }
         }
-
-        wl1271_write32(wl, RX_DRIVER_COUNTER_ADDRESS, wl->rx_counter);
+        wl1271_write32(wl, RX_DRIVER_COUNTER_ADDRESS,
+                        cpu_to_le32(wl->rx_counter));
 }