ath5k: implement multi-rate retry support, fix tx status reporting

Clean up the tx status reporting, fix retry counters (short retries are
virtual collisions, not actual retries). Implement multi-rate retry
support.
This also fixes strong throughput fluctuations with rc80211_pid

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

3 files changed, 95 insertions, 26 deletions

diff --git a/drivers/net/wireless/ath5k/ath5k.h b/drivers/net/wireless/ath5k/ath5k.h
index 7134c40d6a69..53ea439aff48 100644
--- a/drivers/net/wireless/ath5k/ath5k.h
+++ b/drivers/net/wireless/ath5k/ath5k.h
@@ -431,7 +431,9 @@ struct ath5k_tx_status {
         u16     ts_seqnum;
         u16     ts_tstamp;
         u8      ts_status;
-        u8      ts_rate;
+        u8      ts_rate[4];
+        u8      ts_retry[4];
+        u8      ts_final_idx;
         s8      ts_rssi;
         u8      ts_shortretry;
         u8      ts_longretry;
diff --git a/drivers/net/wireless/ath5k/base.c b/drivers/net/wireless/ath5k/base.c
index 47be49acf55e..9b95c4049b31 100644
--- a/drivers/net/wireless/ath5k/base.c
+++ b/drivers/net/wireless/ath5k/base.c
@@ -541,6 +541,12 @@ ath5k_pci_probe(struct pci_dev *pdev,
                 goto err_irq;
         }
 
+        /* set up multi-rate retry capabilities */
+        if (sc->ah->ah_version == AR5K_AR5212) {
+                hw->max_altrates = 3;
+                hw->max_altrate_tries = 11;
+        }
+
         /* Finish private driver data initialization */
         ret = ath5k_attach(pdev, hw);
         if (ret)
@@ -1173,7 +1179,9 @@ ath5k_txbuf_setup(struct ath5k_softc *sc, struct ath5k_buf *bf)
         struct sk_buff *skb = bf->skb;
         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
         unsigned int pktlen, flags, keyidx = AR5K_TXKEYIX_INVALID;
-        int ret;
+        struct ieee80211_rate *rate;
+        unsigned int mrr_rate[3], mrr_tries[3];
+        int i, ret;
 
         flags = AR5K_TXDESC_INTREQ | AR5K_TXDESC_CLRDMASK;
 
@@ -1198,6 +1206,22 @@ ath5k_txbuf_setup(struct ath5k_softc *sc, struct ath5k_buf *bf)
         if (ret)
                 goto err_unmap;
 
+        memset(mrr_rate, 0, sizeof(mrr_rate));
+        memset(mrr_tries, 0, sizeof(mrr_tries));
+        for (i = 0; i < 3; i++) {
+                rate = ieee80211_get_alt_retry_rate(sc->hw, info, i);
+                if (!rate)
+                        break;
+
+                mrr_rate[i] = rate->hw_value;
+                mrr_tries[i] = info->control.retries[i].limit;
+        }
+
+        ah->ah_setup_mrr_tx_desc(ah, ds,
+                mrr_rate[0], mrr_tries[0],
+                mrr_rate[1], mrr_tries[1],
+                mrr_rate[2], mrr_tries[2]);
+
         ds->ds_link = 0;
         ds->ds_data = bf->skbaddr;
 
@@ -1814,7 +1838,7 @@ ath5k_tx_processq(struct ath5k_softc *sc, struct ath5k_txq *txq)
         struct ath5k_desc *ds;
         struct sk_buff *skb;
         struct ieee80211_tx_info *info;
-        int ret;
+        int i, ret;
 
         spin_lock(&txq->lock);
         list_for_each_entry_safe(bf, bf0, &txq->q, list) {
@@ -1836,7 +1860,25 @@ ath5k_tx_processq(struct ath5k_softc *sc, struct ath5k_txq *txq)
                 pci_unmap_single(sc->pdev, bf->skbaddr, skb->len,
                                 PCI_DMA_TODEVICE);
 
-                info->status.retry_count = ts.ts_shortretry + ts.ts_longretry / 6;
+                memset(&info->status, 0, sizeof(info->status));
+                info->tx_rate_idx = ath5k_hw_to_driver_rix(sc,
+                                ts.ts_rate[ts.ts_final_idx]);
+                info->status.retry_count = ts.ts_longretry;
+
+                for (i = 0; i < 4; i++) {
+                        struct ieee80211_tx_altrate *r =
+                                &info->status.retries[i];
+
+                        if (ts.ts_rate[i]) {
+                                r->rate_idx = ath5k_hw_to_driver_rix(sc, ts.ts_rate[i]);
+                                r->limit = ts.ts_retry[i];
+                        } else {
+                                r->rate_idx = -1;
+                                r->limit = 0;
+                        }
+                }
+
+                info->status.excessive_retries = 0;
                 if (unlikely(ts.ts_status)) {
                         sc->ll_stats.dot11ACKFailureCount++;
                         if (ts.ts_status & AR5K_TXERR_XRETRY)
diff --git a/drivers/net/wireless/ath5k/desc.c b/drivers/net/wireless/ath5k/desc.c
index d45b90a6e06c..dd1374052ba9 100644
--- a/drivers/net/wireless/ath5k/desc.c
+++ b/drivers/net/wireless/ath5k/desc.c
@@ -318,6 +318,15 @@ ath5k_hw_setup_mrr_tx_desc(struct ath5k_hw *ah, struct ath5k_desc *desc,
         return 0;
 }
 
+/* no mrr support for cards older than 5212 */
+static int
+ath5k_hw_setup_no_mrr(struct ath5k_hw *ah, struct ath5k_desc *desc,
+        unsigned int tx_rate1, u_int tx_tries1, u_int tx_rate2,
+        u_int tx_tries2, unsigned int tx_rate3, u_int tx_tries3)
+{
+        return 0;
+}
+
 /*
  * Proccess the tx status descriptor on 5210/5211
  */
@@ -352,8 +361,10 @@ static int ath5k_hw_proc_2word_tx_status(struct ath5k_hw *ah,
                 AR5K_DESC_TX_STATUS1_ACK_SIG_STRENGTH);
         ts->ts_antenna = 1;
         ts->ts_status = 0;
-        ts->ts_rate = AR5K_REG_MS(tx_ctl->tx_control_0,
+        ts->ts_rate[0] = AR5K_REG_MS(tx_ctl->tx_control_0,
                 AR5K_2W_TX_DESC_CTL0_XMIT_RATE);
+        ts->ts_retry[0] = ts->ts_longretry;
+        ts->ts_final_idx = 0;
 
         if (!(tx_status->tx_status_0 & AR5K_DESC_TX_STATUS0_FRAME_XMIT_OK)) {
                 if (tx_status->tx_status_0 &
@@ -405,29 +416,43 @@ static int ath5k_hw_proc_4word_tx_status(struct ath5k_hw *ah,
                 AR5K_DESC_TX_STATUS1_XMIT_ANTENNA) ? 2 : 1;
         ts->ts_status = 0;
 
-        switch (AR5K_REG_MS(tx_status->tx_status_1,
-                        AR5K_DESC_TX_STATUS1_FINAL_TS_INDEX)) {
-        case 0:
-                ts->ts_rate = tx_ctl->tx_control_3 &
-                        AR5K_4W_TX_DESC_CTL3_XMIT_RATE0;
-                break;
+        ts->ts_final_idx = AR5K_REG_MS(tx_status->tx_status_1,
+                        AR5K_DESC_TX_STATUS1_FINAL_TS_INDEX);
+
+        /* The longretry counter has the number of un-acked retries
+         * for the final rate. To get the total number of retries
+         * we have to add the retry counters for the other rates
+         * as well
+         */
+        ts->ts_retry[ts->ts_final_idx] = ts->ts_longretry;
+        switch (ts->ts_final_idx) {
+        case 3:
+                ts->ts_rate[3] = AR5K_REG_MS(tx_ctl->tx_control_3,
+                        AR5K_4W_TX_DESC_CTL3_XMIT_RATE3);
+
+                ts->ts_retry[2] = AR5K_REG_MS(tx_ctl->tx_control_2,
+                        AR5K_4W_TX_DESC_CTL2_XMIT_TRIES2);
+                ts->ts_longretry += ts->ts_retry[2];
+                /* fall through */
+        case 2:
+                ts->ts_rate[2] = AR5K_REG_MS(tx_ctl->tx_control_3,
+                        AR5K_4W_TX_DESC_CTL3_XMIT_RATE2);
+
+                ts->ts_retry[1] = AR5K_REG_MS(tx_ctl->tx_control_2,
+                        AR5K_4W_TX_DESC_CTL2_XMIT_TRIES1);
+                ts->ts_longretry += ts->ts_retry[1];
+                /* fall through */
         case 1:
-                ts->ts_rate = AR5K_REG_MS(tx_ctl->tx_control_3,
+                ts->ts_rate[1] = AR5K_REG_MS(tx_ctl->tx_control_3,
                         AR5K_4W_TX_DESC_CTL3_XMIT_RATE1);
-                ts->ts_longretry += AR5K_REG_MS(tx_ctl->tx_control_2,
+
+                ts->ts_retry[0] = AR5K_REG_MS(tx_ctl->tx_control_2,
                         AR5K_4W_TX_DESC_CTL2_XMIT_TRIES1);
-                break;
-        case 2:
-                ts->ts_rate = AR5K_REG_MS(tx_ctl->tx_control_3,
-                        AR5K_4W_TX_DESC_CTL3_XMIT_RATE2);
-                ts->ts_longretry += AR5K_REG_MS(tx_ctl->tx_control_2,
-                        AR5K_4W_TX_DESC_CTL2_XMIT_TRIES2);
-                break;
-        case 3:
-                ts->ts_rate = AR5K_REG_MS(tx_ctl->tx_control_3,
-                        AR5K_4W_TX_DESC_CTL3_XMIT_RATE3);
-                ts->ts_longretry += AR5K_REG_MS(tx_ctl->tx_control_2,
-                        AR5K_4W_TX_DESC_CTL2_XMIT_TRIES3);
+                ts->ts_longretry += ts->ts_retry[0];
+                /* fall through */
+        case 0:
+                ts->ts_rate[0] = tx_ctl->tx_control_3 &
+                        AR5K_4W_TX_DESC_CTL3_XMIT_RATE0;
                 break;
         }
 
@@ -653,7 +678,7 @@ int ath5k_hw_init_desc_functions(struct ath5k_hw *ah)
         } else {
                 ah->ah_setup_rx_desc = ath5k_hw_setup_rx_desc;
                 ah->ah_setup_tx_desc = ath5k_hw_setup_2word_tx_desc;
-                ah->ah_setup_mrr_tx_desc = ath5k_hw_setup_mrr_tx_desc;
+                ah->ah_setup_mrr_tx_desc = ath5k_hw_setup_no_mrr;
                 ah->ah_proc_tx_desc = ath5k_hw_proc_2word_tx_status;
         }