p54: enhance firmware parser to reduce memory waste

This patch greatly reduces one of biggest memory waste in the driver.

The firmware headers provides the right values for extra head-/tailroom
and mtu size which are usually much lower than the old hardcoded ones.

Signed-off-by: Christian Lamparter <chunkeey@web.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 24 insertions, 12 deletions

diff --git a/drivers/net/wireless/p54/p54common.c b/drivers/net/wireless/p54/p54common.c
index 6da98e6e6a9a..fa61749b467b 100644
--- a/drivers/net/wireless/p54/p54common.c
+++ b/drivers/net/wireless/p54/p54common.c
@@ -66,8 +66,7 @@ static struct ieee80211_supported_band band_2GHz = {
         .n_bitrates = ARRAY_SIZE(p54_rates),
 };
 
-
-void p54_parse_firmware(struct ieee80211_hw *dev, const struct firmware *fw)
+int p54_parse_firmware(struct ieee80211_hw *dev, const struct firmware *fw)
 {
         struct p54_common *priv = dev->priv;
         struct bootrec_exp_if *exp_if;
@@ -79,7 +78,7 @@ void p54_parse_firmware(struct ieee80211_hw *dev, const struct firmware *fw)
         int i;
 
         if (priv->rx_start)
-                return;
+                return 0;
 
         while (data < end_data && *data)
                 data++;
@@ -117,11 +116,22 @@ void p54_parse_firmware(struct ieee80211_hw *dev, const struct firmware *fw)
                         if (strnlen((unsigned char*)bootrec->data, 24) < 24)
                                 fw_version = (unsigned char*)bootrec->data;
                         break;
-                case BR_CODE_DESCR:
-                        priv->rx_start = le32_to_cpu(((__le32 *)bootrec->data)[1]);
+                case BR_CODE_DESCR: {
+                        struct bootrec_desc *desc =
+                                (struct bootrec_desc *)bootrec->data;
+                        priv->rx_start = le32_to_cpu(desc->rx_start);
                         /* FIXME add sanity checking */
-                        priv->rx_end = le32_to_cpu(((__le32 *)bootrec->data)[2]) - 0x3500;
+                        priv->rx_end = le32_to_cpu(desc->rx_end) - 0x3500;
+                        priv->headroom = desc->headroom;
+                        priv->tailroom = desc->tailroom;
+                        if (bootrec->len == 11)
+                                priv->rx_mtu = (size_t) le16_to_cpu(
+                                        (__le16)bootrec->data[10]);
+                        else
+                                priv->rx_mtu = (size_t)
+                                        0x620 - priv->tx_hdr_len;
                         break;
+                        }
                 case BR_CODE_EXPOSED_IF:
                         exp_if = (struct bootrec_exp_if *) bootrec->data;
                         for (i = 0; i < (len * sizeof(*exp_if) / 4); i++)
@@ -152,6 +162,8 @@ void p54_parse_firmware(struct ieee80211_hw *dev, const struct firmware *fw)
                 priv->tx_stats[7].limit = 1;
                 dev->queues = 4;
         }
+
+        return 0;
 }
 EXPORT_SYMBOL_GPL(p54_parse_firmware);
 
@@ -428,7 +440,7 @@ static void p54_rx_frame_sent(struct ieee80211_hw *dev, struct sk_buff *skb)
         struct p54_control_hdr *hdr = (struct p54_control_hdr *) skb->data;
         struct p54_frame_sent_hdr *payload = (struct p54_frame_sent_hdr *) hdr->data;
         struct sk_buff *entry = (struct sk_buff *) priv->tx_queue.next;
-        u32 addr = le32_to_cpu(hdr->req_id) - 0x70;
+        u32 addr = le32_to_cpu(hdr->req_id) - priv->headroom;
         struct memrecord *range = NULL;
         u32 freed = 0;
         u32 last_addr = priv->rx_start;
@@ -550,7 +562,7 @@ static void p54_assign_address(struct ieee80211_hw *dev, struct sk_buff *skb,
         u32 target_addr = priv->rx_start;
         unsigned long flags;
         unsigned int left;
-        len = (len + 0x170 + 3) & ~0x3; /* 0x70 headroom, 0x100 tailroom */
+        len = (len + priv->headroom + priv->tailroom + 3) & ~0x3;
 
         spin_lock_irqsave(&priv->tx_queue.lock, flags);
         left = skb_queue_len(&priv->tx_queue);
@@ -585,13 +597,14 @@ static void p54_assign_address(struct ieee80211_hw *dev, struct sk_buff *skb,
                 range->start_addr = target_addr;
                 range->end_addr = target_addr + len;
                 __skb_queue_after(&priv->tx_queue, target_skb, skb);
-                if (largest_hole < IEEE80211_MAX_RTS_THRESHOLD + 0x170 +
+                if (largest_hole < priv->rx_mtu + priv->headroom +
+                                   priv->tailroom +
                                    sizeof(struct p54_control_hdr))
                         ieee80211_stop_queues(dev);
         }
         spin_unlock_irqrestore(&priv->tx_queue.lock, flags);
 
-        data->req_id = cpu_to_le32(target_addr + 0x70);
+        data->req_id = cpu_to_le32(target_addr + priv->headroom);
 }
 
 static int p54_tx(struct ieee80211_hw *dev, struct sk_buff *skb)
@@ -704,7 +717,7 @@ static int p54_set_filter(struct ieee80211_hw *dev, u16 filter_type,
         filter->antenna = antenna;
         filter->magic3 = cpu_to_le32(magic3);
         filter->rx_addr = cpu_to_le32(priv->rx_end);
-        filter->max_rx = cpu_to_le16(0x0620);   /* FIXME: for usb ver 1.. maybe */
+        filter->max_rx = cpu_to_le16(priv->rx_mtu);
         filter->rxhw = priv->rxhw;
         filter->magic8 = cpu_to_le16(magic8);
         filter->magic9 = cpu_to_le16(magic9);
@@ -1084,7 +1097,6 @@ struct ieee80211_hw *p54_init_common(size_t priv_data_len)
         priv->tx_stats[3].limit = 1;
         priv->tx_stats[4].limit = 5;
         dev->queues = 1;
-
         dev->extra_tx_headroom = sizeof(struct p54_control_hdr) + 4 +
                                  sizeof(struct p54_tx_control_allocdata);