1 files changed, 619 insertions, 0 deletions

diff --git a/drivers/staging/wfx/queue.c b/drivers/staging/wfx/queue.c
new file mode 100644
index 000000000000..c7ee90888f69
--- /dev/null
+++ b/drivers/staging/wfx/queue.c
@@ -0,0 +1,619 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * O(1) TX queue with built-in allocator.
+ *
+ * Copyright (c) 2017-2019, Silicon Laboratories, Inc.
+ * Copyright (c) 2010, ST-Ericsson
+ */
+#include <linux/sched.h>
+#include <net/mac80211.h>
+
+#include "queue.h"
+#include "wfx.h"
+#include "sta.h"
+#include "data_tx.h"
+
+void wfx_tx_lock(struct wfx_dev *wdev)
+{
+	atomic_inc(&wdev->tx_lock);
+}
+
+void wfx_tx_unlock(struct wfx_dev *wdev)
+{
+	int tx_lock = atomic_dec_return(&wdev->tx_lock);
+
+	WARN(tx_lock < 0, "inconsistent tx_lock value");
+	if (!tx_lock)
+		wfx_bh_request_tx(wdev);
+}
+
+void wfx_tx_flush(struct wfx_dev *wdev)
+{
+	int ret;
+
+	WARN(!atomic_read(&wdev->tx_lock), "tx_lock is not locked");
+
+	// Do not wait for any reply if chip is frozen
+	if (wdev->chip_frozen)
+		return;
+
+	mutex_lock(&wdev->hif_cmd.lock);
+	ret = wait_event_timeout(wdev->hif.tx_buffers_empty,
+				 !wdev->hif.tx_buffers_used,
+				 msecs_to_jiffies(3000));
+	if (!ret) {
+		dev_warn(wdev->dev, "cannot flush tx buffers (%d still busy)\n",
+			 wdev->hif.tx_buffers_used);
+		wfx_pending_dump_old_frames(wdev, 3000);
+		// FIXME: drop pending frames here
+		wdev->chip_frozen = 1;
+	}
+	mutex_unlock(&wdev->hif_cmd.lock);
+}
+
+void wfx_tx_lock_flush(struct wfx_dev *wdev)
+{
+	wfx_tx_lock(wdev);
+	wfx_tx_flush(wdev);
+}
+
+void wfx_tx_queues_lock(struct wfx_dev *wdev)
+{
+	int i;
+	struct wfx_queue *queue;
+
+	for (i = 0; i < IEEE80211_NUM_ACS; ++i) {
+		queue = &wdev->tx_queue[i];
+		spin_lock_bh(&queue->queue.lock);
+		if (queue->tx_locked_cnt++ == 0)
+			ieee80211_stop_queue(wdev->hw, queue->queue_id);
+		spin_unlock_bh(&queue->queue.lock);
+	}
+}
+
+void wfx_tx_queues_unlock(struct wfx_dev *wdev)
+{
+	int i;
+	struct wfx_queue *queue;
+
+	for (i = 0; i < IEEE80211_NUM_ACS; ++i) {
+		queue = &wdev->tx_queue[i];
+		spin_lock_bh(&queue->queue.lock);
+		WARN(!queue->tx_locked_cnt, "queue already unlocked");
+		if (--queue->tx_locked_cnt == 0)
+			ieee80211_wake_queue(wdev->hw, queue->queue_id);
+		spin_unlock_bh(&queue->queue.lock);
+	}
+}
+
+/* If successful, LOCKS the TX queue! */
+void wfx_tx_queues_wait_empty_vif(struct wfx_vif *wvif)
+{
+	int i;
+	bool done;
+	struct wfx_queue *queue;
+	struct sk_buff *item;
+	struct wfx_dev *wdev = wvif->wdev;
+	struct hif_msg *hif;
+
+	if (wvif->wdev->chip_frozen) {
+		wfx_tx_lock_flush(wdev);
+		wfx_tx_queues_clear(wdev);
+		return;
+	}
+
+	do {
+		done = true;
+		wfx_tx_lock_flush(wdev);
+		for (i = 0; i < IEEE80211_NUM_ACS && done; ++i) {
+			queue = &wdev->tx_queue[i];
+			spin_lock_bh(&queue->queue.lock);
+			skb_queue_walk(&queue->queue, item) {
+				hif = (struct hif_msg *) item->data;
+				if (hif->interface == wvif->id)
+					done = false;
+			}
+			spin_unlock_bh(&queue->queue.lock);
+		}
+		if (!done) {
+			wfx_tx_unlock(wdev);
+			msleep(20);
+		}
+	} while (!done);
+}
+
+static void wfx_tx_queue_clear(struct wfx_dev *wdev, struct wfx_queue *queue,
+			       struct sk_buff_head *gc_list)
+{
+	int i;
+	struct sk_buff *item;
+	struct wfx_queue_stats *stats = &wdev->tx_queue_stats;
+
+	spin_lock_bh(&queue->queue.lock);
+	while ((item = __skb_dequeue(&queue->queue)) != NULL)
+		skb_queue_head(gc_list, item);
+	spin_lock_bh(&stats->pending.lock);
+	for (i = 0; i < ARRAY_SIZE(stats->link_map_cache); ++i) {
+		stats->link_map_cache[i] -= queue->link_map_cache[i];
+		queue->link_map_cache[i] = 0;
+	}
+	spin_unlock_bh(&stats->pending.lock);
+	spin_unlock_bh(&queue->queue.lock);
+}
+
+void wfx_tx_queues_clear(struct wfx_dev *wdev)
+{
+	int i;
+	struct sk_buff *item;
+	struct sk_buff_head gc_list;
+	struct wfx_queue_stats *stats = &wdev->tx_queue_stats;
+
+	skb_queue_head_init(&gc_list);
+	for (i = 0; i < IEEE80211_NUM_ACS; ++i)
+		wfx_tx_queue_clear(wdev, &wdev->tx_queue[i], &gc_list);
+	wake_up(&stats->wait_link_id_empty);
+	while ((item = skb_dequeue(&gc_list)) != NULL)
+		wfx_skb_dtor(wdev, item);
+}
+
+void wfx_tx_queues_init(struct wfx_dev *wdev)
+{
+	int i;
+
+	memset(&wdev->tx_queue_stats, 0, sizeof(wdev->tx_queue_stats));
+	memset(wdev->tx_queue, 0, sizeof(wdev->tx_queue));
+	skb_queue_head_init(&wdev->tx_queue_stats.pending);
+	init_waitqueue_head(&wdev->tx_queue_stats.wait_link_id_empty);
+
+	for (i = 0; i < IEEE80211_NUM_ACS; ++i) {
+		wdev->tx_queue[i].queue_id = i;
+		skb_queue_head_init(&wdev->tx_queue[i].queue);
+	}
+}
+
+void wfx_tx_queues_deinit(struct wfx_dev *wdev)
+{
+	WARN_ON(!skb_queue_empty(&wdev->tx_queue_stats.pending));
+	wfx_tx_queues_clear(wdev);
+}
+
+size_t wfx_tx_queue_get_num_queued(struct wfx_queue *queue,
+				   u32 link_id_map)
+{
+	size_t ret;
+	int i, bit;
+
+	if (!link_id_map)
+		return 0;
+
+	spin_lock_bh(&queue->queue.lock);
+	if (link_id_map == (u32)-1) {
+		ret = skb_queue_len(&queue->queue);
+	} else {
+		ret = 0;
+		for (i = 0, bit = 1; i < ARRAY_SIZE(queue->link_map_cache);
+		     ++i, bit <<= 1) {
+			if (link_id_map & bit)
+				ret += queue->link_map_cache[i];
+		}
+	}
+	spin_unlock_bh(&queue->queue.lock);
+	return ret;
+}
+
+void wfx_tx_queue_put(struct wfx_dev *wdev, struct wfx_queue *queue,
+		      struct sk_buff *skb)
+{
+	struct wfx_queue_stats *stats = &wdev->tx_queue_stats;
+	struct wfx_tx_priv *tx_priv = wfx_skb_tx_priv(skb);
+
+	WARN(tx_priv->link_id >= ARRAY_SIZE(stats->link_map_cache), "invalid link-id value");
+	spin_lock_bh(&queue->queue.lock);
+	__skb_queue_tail(&queue->queue, skb);
+
+	++queue->link_map_cache[tx_priv->link_id];
+
+	spin_lock_bh(&stats->pending.lock);
+	++stats->link_map_cache[tx_priv->link_id];
+	spin_unlock_bh(&stats->pending.lock);
+	spin_unlock_bh(&queue->queue.lock);
+}
+
+static struct sk_buff *wfx_tx_queue_get(struct wfx_dev *wdev,
+					struct wfx_queue *queue,
+					u32 link_id_map)
+{
+	struct sk_buff *skb = NULL;
+	struct sk_buff *item;
+	struct wfx_queue_stats *stats = &wdev->tx_queue_stats;
+	struct wfx_tx_priv *tx_priv;
+	bool wakeup_stats = false;
+
+	spin_lock_bh(&queue->queue.lock);
+	skb_queue_walk(&queue->queue, item) {
+		tx_priv = wfx_skb_tx_priv(item);
+		if (link_id_map & BIT(tx_priv->link_id)) {
+			skb = item;
+			break;
+		}
+	}
+	WARN_ON(!skb);
+	if (skb) {
+		tx_priv = wfx_skb_tx_priv(skb);
+		tx_priv->xmit_timestamp = ktime_get();
+		__skb_unlink(skb, &queue->queue);
+		--queue->link_map_cache[tx_priv->link_id];
+
+		spin_lock_bh(&stats->pending.lock);
+		__skb_queue_tail(&stats->pending, skb);
+		if (!--stats->link_map_cache[tx_priv->link_id])
+			wakeup_stats = true;
+		spin_unlock_bh(&stats->pending.lock);
+	}
+	spin_unlock_bh(&queue->queue.lock);
+	if (wakeup_stats)
+		wake_up(&stats->wait_link_id_empty);
+	return skb;
+}
+
+int wfx_pending_requeue(struct wfx_dev *wdev, struct sk_buff *skb)
+{
+	struct wfx_queue_stats *stats = &wdev->tx_queue_stats;
+	struct wfx_tx_priv *tx_priv = wfx_skb_tx_priv(skb);
+	struct wfx_queue *queue = &wdev->tx_queue[skb_get_queue_mapping(skb)];
+
+	WARN_ON(skb_get_queue_mapping(skb) > 3);
+	spin_lock_bh(&queue->queue.lock);
+	++queue->link_map_cache[tx_priv->link_id];
+
+	spin_lock_bh(&stats->pending.lock);
+	++stats->link_map_cache[tx_priv->link_id];
+	__skb_unlink(skb, &stats->pending);
+	spin_unlock_bh(&stats->pending.lock);
+	__skb_queue_tail(&queue->queue, skb);
+	spin_unlock_bh(&queue->queue.lock);
+	return 0;
+}
+
+int wfx_pending_remove(struct wfx_dev *wdev, struct sk_buff *skb)
+{
+	struct wfx_queue_stats *stats = &wdev->tx_queue_stats;
+
+	spin_lock_bh(&stats->pending.lock);
+	__skb_unlink(skb, &stats->pending);
+	spin_unlock_bh(&stats->pending.lock);
+	wfx_skb_dtor(wdev, skb);
+
+	return 0;
+}
+
+struct sk_buff *wfx_pending_get(struct wfx_dev *wdev, u32 packet_id)
+{
+	struct sk_buff *skb;
+	struct hif_req_tx *req;
+	struct wfx_queue_stats *stats = &wdev->tx_queue_stats;
+
+	spin_lock_bh(&stats->pending.lock);
+	skb_queue_walk(&stats->pending, skb) {
+		req = wfx_skb_txreq(skb);
+		if (req->packet_id == packet_id) {
+			spin_unlock_bh(&stats->pending.lock);
+			return skb;
+		}
+	}
+	spin_unlock_bh(&stats->pending.lock);
+	WARN(1, "cannot find packet in pending queue");
+	return NULL;
+}
+
+void wfx_pending_dump_old_frames(struct wfx_dev *wdev, unsigned int limit_ms)
+{
+	struct wfx_queue_stats *stats = &wdev->tx_queue_stats;
+	ktime_t now = ktime_get();
+	struct wfx_tx_priv *tx_priv;
+	struct hif_req_tx *req;
+	struct sk_buff *skb;
+	bool first = true;
+
+	spin_lock_bh(&stats->pending.lock);
+	skb_queue_walk(&stats->pending, skb) {
+		tx_priv = wfx_skb_tx_priv(skb);
+		req = wfx_skb_txreq(skb);
+		if (ktime_after(now, ktime_add_ms(tx_priv->xmit_timestamp,
+						  limit_ms))) {
+			if (first) {
+				dev_info(wdev->dev, "frames stuck in firmware since %dms or more:\n",
+					 limit_ms);
+				first = false;
+			}
+			dev_info(wdev->dev, "   id %08x sent %lldms ago\n",
+				 req->packet_id,
+				 ktime_ms_delta(now, tx_priv->xmit_timestamp));
+		}
+	}
+	spin_unlock_bh(&stats->pending.lock);
+}
+
+unsigned int wfx_pending_get_pkt_us_delay(struct wfx_dev *wdev,
+					  struct sk_buff *skb)
+{
+	ktime_t now = ktime_get();
+	struct wfx_tx_priv *tx_priv = wfx_skb_tx_priv(skb);
+
+	return ktime_us_delta(now, tx_priv->xmit_timestamp);
+}
+
+bool wfx_tx_queues_is_empty(struct wfx_dev *wdev)
+{
+	int i;
+	struct sk_buff_head *queue;
+	bool ret = true;
+
+	for (i = 0; i < IEEE80211_NUM_ACS; i++) {
+		queue = &wdev->tx_queue[i].queue;
+		spin_lock_bh(&queue->lock);
+		if (!skb_queue_empty(queue))
+			ret = false;
+		spin_unlock_bh(&queue->lock);
+	}
+	return ret;
+}
+
+static bool hif_handle_tx_data(struct wfx_vif *wvif, struct sk_buff *skb,
+			       struct wfx_queue *queue)
+{
+	bool handled = false;
+	struct wfx_tx_priv *tx_priv = wfx_skb_tx_priv(skb);
+	struct hif_req_tx *req = wfx_skb_txreq(skb);
+	struct ieee80211_hdr *frame = (struct ieee80211_hdr *) (req->frame + req->data_flags.fc_offset);
+
+	enum {
+		do_probe,
+		do_drop,
+		do_wep,
+		do_tx,
+	} action = do_tx;
+
+	switch (wvif->vif->type) {
+	case NL80211_IFTYPE_STATION:
+		if (wvif->state < WFX_STATE_PRE_STA)
+			action = do_drop;
+		break;
+	case NL80211_IFTYPE_AP:
+		if (!wvif->state) {
+			action = do_drop;
+		} else if (!(BIT(tx_priv->raw_link_id) &
+			     (BIT(0) | wvif->link_id_map))) {
+			dev_warn(wvif->wdev->dev, "a frame with expired link-id is dropped\n");
+			action = do_drop;
+		}
+		break;
+	case NL80211_IFTYPE_ADHOC:
+		if (wvif->state != WFX_STATE_IBSS)
+			action = do_drop;
+		break;
+	case NL80211_IFTYPE_MONITOR:
+	default:
+		action = do_drop;
+		break;
+	}
+
+	if (action == do_tx) {
+		if (ieee80211_is_nullfunc(frame->frame_control)) {
+			mutex_lock(&wvif->bss_loss_lock);
+			if (wvif->bss_loss_state) {
+				wvif->bss_loss_confirm_id = req->packet_id;
+				req->queue_id.queue_id = HIF_QUEUE_ID_VOICE;
+			}
+			mutex_unlock(&wvif->bss_loss_lock);
+		} else if (ieee80211_has_protected(frame->frame_control) &&
+			   tx_priv->hw_key &&
+			   tx_priv->hw_key->keyidx != wvif->wep_default_key_id &&
+			   (tx_priv->hw_key->cipher == WLAN_CIPHER_SUITE_WEP40 ||
+			    tx_priv->hw_key->cipher == WLAN_CIPHER_SUITE_WEP104)) {
+			action = do_wep;
+		}
+	}
+
+	switch (action) {
+	case do_drop:
+		wfx_pending_remove(wvif->wdev, skb);
+		handled = true;
+		break;
+	case do_wep:
+		wfx_tx_lock(wvif->wdev);
+		wvif->wep_default_key_id = tx_priv->hw_key->keyidx;
+		wvif->wep_pending_skb = skb;
+		if (!schedule_work(&wvif->wep_key_work))
+			wfx_tx_unlock(wvif->wdev);
+		handled = true;
+		break;
+	case do_tx:
+		break;
+	default:
+		/* Do nothing */
+		break;
+	}
+	return handled;
+}
+
+static int wfx_get_prio_queue(struct wfx_vif *wvif,
+				 u32 tx_allowed_mask, int *total)
+{
+	static const int urgent = BIT(WFX_LINK_ID_AFTER_DTIM) |
+		BIT(WFX_LINK_ID_UAPSD);
+	struct hif_req_edca_queue_params *edca;
+	unsigned int score, best = -1;
+	int winner = -1;
+	int i;
+
+	/* search for a winner using edca params */
+	for (i = 0; i < IEEE80211_NUM_ACS; ++i) {
+		int queued;
+
+		edca = &wvif->edca.params[i];
+		queued = wfx_tx_queue_get_num_queued(&wvif->wdev->tx_queue[i],
+				tx_allowed_mask);
+		if (!queued)
+			continue;
+		*total += queued;
+		score = ((edca->aifsn + edca->cw_min) << 16) +
+			((edca->cw_max - edca->cw_min) *
+			 (get_random_int() & 0xFFFF));
+		if (score < best && (winner < 0 || i != 3)) {
+			best = score;
+			winner = i;
+		}
+	}
+
+	/* override winner if bursting */
+	if (winner >= 0 && wvif->wdev->tx_burst_idx >= 0 &&
+	    winner != wvif->wdev->tx_burst_idx &&
+	    !wfx_tx_queue_get_num_queued(&wvif->wdev->tx_queue[winner],
+					 tx_allowed_mask & urgent) &&
+	    wfx_tx_queue_get_num_queued(&wvif->wdev->tx_queue[wvif->wdev->tx_burst_idx], tx_allowed_mask))
+		winner = wvif->wdev->tx_burst_idx;
+
+	return winner;
+}
+
+static int wfx_tx_queue_mask_get(struct wfx_vif *wvif,
+				     struct wfx_queue **queue_p,
+				     u32 *tx_allowed_mask_p,
+				     bool *more)
+{
+	int idx;
+	u32 tx_allowed_mask;
+	int total = 0;
+
+	/* Search for a queue with multicast frames buffered */
+	if (wvif->mcast_tx) {
+		tx_allowed_mask = BIT(WFX_LINK_ID_AFTER_DTIM);
+		idx = wfx_get_prio_queue(wvif, tx_allowed_mask, &total);
+		if (idx >= 0) {
+			*more = total > 1;
+			goto found;
+		}
+	}
+
+	/* Search for unicast traffic */
+	tx_allowed_mask = ~wvif->sta_asleep_mask;
+	tx_allowed_mask |= BIT(WFX_LINK_ID_UAPSD);
+	if (wvif->sta_asleep_mask) {
+		tx_allowed_mask |= wvif->pspoll_mask;
+		tx_allowed_mask &= ~BIT(WFX_LINK_ID_AFTER_DTIM);
+	} else {
+		tx_allowed_mask |= BIT(WFX_LINK_ID_AFTER_DTIM);
+	}
+	idx = wfx_get_prio_queue(wvif, tx_allowed_mask, &total);
+	if (idx < 0)
+		return -ENOENT;
+
+found:
+	*queue_p = &wvif->wdev->tx_queue[idx];
+	*tx_allowed_mask_p = tx_allowed_mask;
+	return 0;
+}
+
+struct hif_msg *wfx_tx_queues_get(struct wfx_dev *wdev)
+{
+	struct sk_buff *skb;
+	struct hif_msg *hif = NULL;
+	struct hif_req_tx *req = NULL;
+	struct wfx_queue *queue = NULL;
+	struct wfx_queue *vif_queue = NULL;
+	u32 tx_allowed_mask = 0;
+	u32 vif_tx_allowed_mask = 0;
+	const struct wfx_tx_priv *tx_priv = NULL;
+	struct wfx_vif *wvif;
+	/* More is used only for broadcasts. */
+	bool more = false;
+	bool vif_more = false;
+	int not_found;
+	int burst;
+
+	for (;;) {
+		int ret = -ENOENT;
+		int queue_num;
+		struct ieee80211_hdr *hdr;
+
+		if (atomic_read(&wdev->tx_lock))
+			return NULL;
+
+		wvif = NULL;
+		while ((wvif = wvif_iterate(wdev, wvif)) != NULL) {
+			spin_lock_bh(&wvif->ps_state_lock);
+
+			not_found = wfx_tx_queue_mask_get(wvif, &vif_queue,
+							  &vif_tx_allowed_mask,
+							  &vif_more);
+
+			if (wvif->mcast_buffered && (not_found || !vif_more) &&
+					(wvif->mcast_tx ||
+					 !wvif->sta_asleep_mask)) {
+				wvif->mcast_buffered = false;
+				if (wvif->mcast_tx) {
+					wvif->mcast_tx = false;
+					schedule_work(&wvif->mcast_stop_work);
+				}
+			}
+
+			spin_unlock_bh(&wvif->ps_state_lock);
+
+			if (vif_more) {
+				more = true;
+				tx_allowed_mask = vif_tx_allowed_mask;
+				queue = vif_queue;
+				ret = 0;
+				break;
+			} else if (!not_found) {
+				if (queue && queue != vif_queue)
+					dev_info(wdev->dev, "vifs disagree about queue priority\n");
+				tx_allowed_mask |= vif_tx_allowed_mask;
+				queue = vif_queue;
+				ret = 0;
+			}
+		}
+
+		if (ret)
+			return NULL;
+
+		queue_num = queue - wdev->tx_queue;
+
+		skb = wfx_tx_queue_get(wdev, queue, tx_allowed_mask);
+		if (!skb)
+			continue;
+		tx_priv = wfx_skb_tx_priv(skb);
+		hif = (struct hif_msg *) skb->data;
+		wvif = wdev_to_wvif(wdev, hif->interface);
+		WARN_ON(!wvif);
+
+		if (hif_handle_tx_data(wvif, skb, queue))
+			continue;  /* Handled by WSM */
+
+		wvif->pspoll_mask &= ~BIT(tx_priv->raw_link_id);
+
+		/* allow bursting if txop is set */
+		if (wvif->edca.params[queue_num].tx_op_limit)
+			burst = (int)wfx_tx_queue_get_num_queued(queue, tx_allowed_mask) + 1;
+		else
+			burst = 1;
+
+		/* store index of bursting queue */
+		if (burst > 1)
+			wdev->tx_burst_idx = queue_num;
+		else
+			wdev->tx_burst_idx = -1;
+
+		/* more buffered multicast/broadcast frames
+		 *  ==> set MoreData flag in IEEE 802.11 header
+		 *  to inform PS STAs
+		 */
+		if (more) {
+			req = (struct hif_req_tx *) hif->body;
+			hdr = (struct ieee80211_hdr *) (req->frame + req->data_flags.fc_offset);
+			hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
+		}
+		return hif;
+	}
+}