From 3517afdefc3ad335b276eb5f8691841f48097abf Mon Sep 17 00:00:00 2001 From: Herton Ronaldo Krzesinski Date: Thu, 13 Nov 2008 10:39:16 -0500 Subject: [PATCH] rtl8187: feedback transmitted packets using tx close descriptor for 8187B Realtek 8187B has a receive command queue to feedback beacon interrupt and transmitted packet status. Use it to feedback mac80211 about status of transmitted packets. Unfortunately in the course of testing I found that the sequence number reported by hardware includes entire sequence control in a 12 bit only field, so a workaround is done to check only lowest bits. Tested-by: Larry Finger Tested-by: Hin-Tak Leung Signed-off-by: Herton Ronaldo Krzesinski Signed-off-by: John W. Linville --- drivers/net/wireless/rtl818x/rtl8187.h | 5 + drivers/net/wireless/rtl818x/rtl8187_dev.c | 135 ++++++++++++++++++++- 2 files changed, 136 insertions(+), 4 deletions(-) diff --git a/drivers/net/wireless/rtl818x/rtl8187.h b/drivers/net/wireless/rtl818x/rtl8187.h index f09872eec3d5..c385407a9941 100644 --- a/drivers/net/wireless/rtl818x/rtl8187.h +++ b/drivers/net/wireless/rtl818x/rtl8187.h @@ -113,6 +113,11 @@ struct rtl8187_priv { u8 noise; u8 slot_time; u8 aifsn[4]; + struct { + __le64 buf; + struct urb *urb; + struct sk_buff_head queue; + } b_tx_status; }; void rtl8187_write_phy(struct ieee80211_hw *dev, u8 addr, u32 data); diff --git a/drivers/net/wireless/rtl818x/rtl8187_dev.c b/drivers/net/wireless/rtl818x/rtl8187_dev.c index cb5bcefd1c3e..876d4f93d310 100644 --- a/drivers/net/wireless/rtl818x/rtl8187_dev.c +++ b/drivers/net/wireless/rtl818x/rtl8187_dev.c @@ -176,8 +176,27 @@ static void rtl8187_tx_cb(struct urb *urb) skb_pull(skb, priv->is_rtl8187b ? sizeof(struct rtl8187b_tx_hdr) : sizeof(struct rtl8187_tx_hdr)); ieee80211_tx_info_clear_status(info); - info->flags |= IEEE80211_TX_STAT_ACK; - ieee80211_tx_status_irqsafe(hw, skb); + + if (!urb->status && + !(info->flags & IEEE80211_TX_CTL_NO_ACK) && + priv->is_rtl8187b) { + skb_queue_tail(&priv->b_tx_status.queue, skb); + + /* queue is "full", discard last items */ + while (skb_queue_len(&priv->b_tx_status.queue) > 5) { + struct sk_buff *old_skb; + + dev_dbg(&priv->udev->dev, + "transmit status queue full\n"); + + old_skb = skb_dequeue(&priv->b_tx_status.queue); + ieee80211_tx_status_irqsafe(hw, old_skb); + } + } else { + if (!(info->flags & IEEE80211_TX_CTL_NO_ACK) && !urb->status) + info->flags |= IEEE80211_TX_STAT_ACK; + ieee80211_tx_status_irqsafe(hw, skb); + } } static int rtl8187_tx(struct ieee80211_hw *dev, struct sk_buff *skb) @@ -219,7 +238,7 @@ static int rtl8187_tx(struct ieee80211_hw *dev, struct sk_buff *skb) hdr->flags = cpu_to_le32(flags); hdr->len = 0; hdr->rts_duration = rts_dur; - hdr->retry = cpu_to_le32((info->control.rates[0].count - 1) << 8); + hdr->retry = cpu_to_le32(info->control.rates[0].count << 8); buf = hdr; ep = 2; @@ -237,7 +256,7 @@ static int rtl8187_tx(struct ieee80211_hw *dev, struct sk_buff *skb) memset(hdr, 0, sizeof(*hdr)); hdr->flags = cpu_to_le32(flags); hdr->rts_duration = rts_dur; - hdr->retry = cpu_to_le32((info->control.rates[0].count - 1) << 8); + hdr->retry = cpu_to_le32(info->control.rates[0].count << 8); hdr->tx_duration = ieee80211_generic_frame_duration(dev, priv->vif, skb->len, txrate); @@ -403,6 +422,109 @@ static int rtl8187_init_urbs(struct ieee80211_hw *dev) return 0; } +static void rtl8187b_status_cb(struct urb *urb) +{ + struct ieee80211_hw *hw = (struct ieee80211_hw *)urb->context; + struct rtl8187_priv *priv = hw->priv; + u64 val; + unsigned int cmd_type; + + if (unlikely(urb->status)) { + usb_free_urb(urb); + return; + } + + /* + * Read from status buffer: + * + * bits [30:31] = cmd type: + * - 0 indicates tx beacon interrupt + * - 1 indicates tx close descriptor + * + * In the case of tx beacon interrupt: + * [0:9] = Last Beacon CW + * [10:29] = reserved + * [30:31] = 00b + * [32:63] = Last Beacon TSF + * + * If it's tx close descriptor: + * [0:7] = Packet Retry Count + * [8:14] = RTS Retry Count + * [15] = TOK + * [16:27] = Sequence No + * [28] = LS + * [29] = FS + * [30:31] = 01b + * [32:47] = unused (reserved?) + * [48:63] = MAC Used Time + */ + val = le64_to_cpu(priv->b_tx_status.buf); + + cmd_type = (val >> 30) & 0x3; + if (cmd_type == 1) { + unsigned int pkt_rc, seq_no; + bool tok; + struct sk_buff *skb; + struct ieee80211_hdr *ieee80211hdr; + unsigned long flags; + + pkt_rc = val & 0xFF; + tok = val & (1 << 15); + seq_no = (val >> 16) & 0xFFF; + + spin_lock_irqsave(&priv->b_tx_status.queue.lock, flags); + skb_queue_reverse_walk(&priv->b_tx_status.queue, skb) { + ieee80211hdr = (struct ieee80211_hdr *)skb->data; + + /* + * While testing, it was discovered that the seq_no + * doesn't actually contains the sequence number. + * Instead of returning just the 12 bits of sequence + * number, hardware is returning entire sequence control + * (fragment number plus sequence number) in a 12 bit + * only field overflowing after some time. As a + * workaround, just consider the lower bits, and expect + * it's unlikely we wrongly ack some sent data + */ + if ((le16_to_cpu(ieee80211hdr->seq_ctrl) + & 0xFFF) == seq_no) + break; + } + if (skb != (struct sk_buff *) &priv->b_tx_status.queue) { + struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); + + __skb_unlink(skb, &priv->b_tx_status.queue); + if (tok) + info->flags |= IEEE80211_TX_STAT_ACK; + info->status.rates[0].count = pkt_rc; + + ieee80211_tx_status_irqsafe(hw, skb); + } + spin_unlock_irqrestore(&priv->b_tx_status.queue.lock, flags); + } + + usb_submit_urb(urb, GFP_ATOMIC); +} + +static int rtl8187b_init_status_urb(struct ieee80211_hw *dev) +{ + struct rtl8187_priv *priv = dev->priv; + struct urb *entry; + + entry = usb_alloc_urb(0, GFP_KERNEL); + if (!entry) + return -ENOMEM; + priv->b_tx_status.urb = entry; + + usb_fill_bulk_urb(entry, priv->udev, usb_rcvbulkpipe(priv->udev, 9), + &priv->b_tx_status.buf, sizeof(priv->b_tx_status.buf), + rtl8187b_status_cb, dev); + + usb_submit_urb(entry, GFP_KERNEL); + + return 0; +} + static int rtl8187_cmd_reset(struct ieee80211_hw *dev) { struct rtl8187_priv *priv = dev->priv; @@ -755,6 +877,7 @@ static int rtl8187_start(struct ieee80211_hw *dev) (7 << 0 /* long retry limit */) | (7 << 21 /* MAX TX DMA */)); rtl8187_init_urbs(dev); + rtl8187b_init_status_urb(dev); mutex_unlock(&priv->conf_mutex); return 0; } @@ -831,6 +954,9 @@ static void rtl8187_stop(struct ieee80211_hw *dev) usb_kill_urb(info->urb); kfree_skb(skb); } + while ((skb = skb_dequeue(&priv->b_tx_status.queue))) + dev_kfree_skb_any(skb); + usb_kill_urb(priv->b_tx_status.urb); mutex_unlock(&priv->conf_mutex); } @@ -1317,6 +1443,7 @@ static int __devinit rtl8187_probe(struct usb_interface *intf, goto err_free_dev; } mutex_init(&priv->conf_mutex); + skb_queue_head_init(&priv->b_tx_status.queue); printk(KERN_INFO "%s: hwaddr %pM, %s V%d + %s\n", wiphy_name(dev->wiphy), dev->wiphy->perm_addr, -- 2.30.2