[PATCH v8 18/24] wfx: add data_tx.c/data_tx.h

[Jerome Pouiller]

From: Jérôme Pouiller <jerome.pouiller@xxxxxxxxxx>

Signed-off-by: Jérôme Pouiller <jerome.pouiller@xxxxxxxxxx>
---
 drivers/net/wireless/silabs/wfx/data_tx.c | 596 ++++++++++++++++++++++
 drivers/net/wireless/silabs/wfx/data_tx.h |  68 +++
 2 files changed, 664 insertions(+)
 create mode 100644 drivers/net/wireless/silabs/wfx/data_tx.c
 create mode 100644 drivers/net/wireless/silabs/wfx/data_tx.h

diff --git a/drivers/net/wireless/silabs/wfx/data_tx.c b/drivers/net/wireless/silabs/wfx/data_tx.c
new file mode 100644
index 000000000000..ba606c79adbe
--- /dev/null
+++ b/drivers/net/wireless/silabs/wfx/data_tx.c
@@ -0,0 +1,596 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Data transmitting implementation.
+ *
+ * Copyright (c) 2017-2020, Silicon Laboratories, Inc.
+ * Copyright (c) 2010, ST-Ericsson
+ */
+#include <net/mac80211.h>
+#include <linux/etherdevice.h>
+
+#include "data_tx.h"
+#include "wfx.h"
+#include "bh.h"
+#include "sta.h"
+#include "queue.h"
+#include "debug.h"
+#include "traces.h"
+#include "hif_tx_mib.h"
+
+static int wfx_get_hw_rate(struct wfx_dev *wdev,
+			   const struct ieee80211_tx_rate *rate)
+{
+	struct ieee80211_supported_band *band;
+
+	if (rate->idx < 0)
+		return -1;
+	if (rate->flags & IEEE80211_TX_RC_MCS) {
+		if (rate->idx > 7) {
+			WARN(1, "wrong rate->idx value: %d", rate->idx);
+			return -1;
+		}
+		return rate->idx + 14;
+	}
+	/* The device only support 2GHz, else band information should be
+	 * retrieved from ieee80211_tx_info
+	 */
+	band = wdev->hw->wiphy->bands[NL80211_BAND_2GHZ];
+	if (rate->idx >= band->n_bitrates) {
+		WARN(1, "wrong rate->idx value: %d", rate->idx);
+		return -1;
+	}
+	return band->bitrates[rate->idx].hw_value;
+}
+
+/* TX policy cache implementation */
+
+static void wfx_tx_policy_build(struct wfx_vif *wvif, struct wfx_tx_policy *policy,
+				struct ieee80211_tx_rate *rates)
+{
+	struct wfx_dev *wdev = wvif->wdev;
+	int i, rateid;
+	u8 count;
+
+	WARN(rates[0].idx < 0, "invalid rate policy");
+	memset(policy, 0, sizeof(*policy));
+	for (i = 0; i < IEEE80211_TX_MAX_RATES; ++i) {
+		if (rates[i].idx < 0)
+			break;
+		WARN_ON(rates[i].count > 15);
+		rateid = wfx_get_hw_rate(wdev, &rates[i]);
+		/* Pack two values in each byte of policy->rates */
+		count = rates[i].count;
+		if (rateid % 2)
+			count <<= 4;
+		policy->rates[rateid / 2] |= count;
+	}
+}
+
+static bool wfx_tx_policy_is_equal(const struct wfx_tx_policy *a,
+				   const struct wfx_tx_policy *b)
+{
+	return !memcmp(a->rates, b->rates, sizeof(a->rates));
+}
+
+static int wfx_tx_policy_find(struct wfx_tx_policy_cache *cache,
+			      struct wfx_tx_policy *wanted)
+{
+	struct wfx_tx_policy *it;
+
+	list_for_each_entry(it, &cache->used, link)
+		if (wfx_tx_policy_is_equal(wanted, it))
+			return it - cache->cache;
+	list_for_each_entry(it, &cache->free, link)
+		if (wfx_tx_policy_is_equal(wanted, it))
+			return it - cache->cache;
+	return -1;
+}
+
+static void wfx_tx_policy_use(struct wfx_tx_policy_cache *cache,
+			      struct wfx_tx_policy *entry)
+{
+	++entry->usage_count;
+	list_move(&entry->link, &cache->used);
+}
+
+static int wfx_tx_policy_release(struct wfx_tx_policy_cache *cache,
+				 struct wfx_tx_policy *entry)
+{
+	int ret = --entry->usage_count;
+
+	if (!ret)
+		list_move(&entry->link, &cache->free);
+	return ret;
+}
+
+static int wfx_tx_policy_get(struct wfx_vif *wvif,
+			     struct ieee80211_tx_rate *rates, bool *renew)
+{
+	int idx;
+	struct wfx_tx_policy_cache *cache = &wvif->tx_policy_cache;
+	struct wfx_tx_policy wanted;
+	struct wfx_tx_policy *entry;
+
+	wfx_tx_policy_build(wvif, &wanted, rates);
+
+	spin_lock_bh(&cache->lock);
+	if (list_empty(&cache->free)) {
+		WARN(1, "unable to get a valid Tx policy");
+		spin_unlock_bh(&cache->lock);
+		return HIF_TX_RETRY_POLICY_INVALID;
+	}
+	idx = wfx_tx_policy_find(cache, &wanted);
+	if (idx >= 0) {
+		*renew = false;
+	} else {
+		/* If policy is not found create a new one using the oldest
+		 * entry in "free" list
+		 */
+		*renew = true;
+		entry = list_entry(cache->free.prev, struct wfx_tx_policy, link);
+		memcpy(entry->rates, wanted.rates, sizeof(entry->rates));
+		entry->uploaded = false;
+		entry->usage_count = 0;
+		idx = entry - cache->cache;
+	}
+	wfx_tx_policy_use(cache, &cache->cache[idx]);
+	if (list_empty(&cache->free))
+		ieee80211_stop_queues(wvif->wdev->hw);
+	spin_unlock_bh(&cache->lock);
+	return idx;
+}
+
+static void wfx_tx_policy_put(struct wfx_vif *wvif, int idx)
+{
+	int usage, locked;
+	struct wfx_tx_policy_cache *cache = &wvif->tx_policy_cache;
+
+	if (idx == HIF_TX_RETRY_POLICY_INVALID)
+		return;
+	spin_lock_bh(&cache->lock);
+	locked = list_empty(&cache->free);
+	usage = wfx_tx_policy_release(cache, &cache->cache[idx]);
+	if (locked && !usage)
+		ieee80211_wake_queues(wvif->wdev->hw);
+	spin_unlock_bh(&cache->lock);
+}
+
+static int wfx_tx_policy_upload(struct wfx_vif *wvif)
+{
+	struct wfx_tx_policy *policies = wvif->tx_policy_cache.cache;
+	u8 tmp_rates[12];
+	int i, is_used;
+
+	do {
+		spin_lock_bh(&wvif->tx_policy_cache.lock);
+		for (i = 0; i < ARRAY_SIZE(wvif->tx_policy_cache.cache); ++i) {
+			is_used = memzcmp(policies[i].rates,
+					  sizeof(policies[i].rates));
+			if (!policies[i].uploaded && is_used)
+				break;
+		}
+		if (i < ARRAY_SIZE(wvif->tx_policy_cache.cache)) {
+			policies[i].uploaded = true;
+			memcpy(tmp_rates, policies[i].rates, sizeof(tmp_rates));
+			spin_unlock_bh(&wvif->tx_policy_cache.lock);
+			wfx_hif_set_tx_rate_retry_policy(wvif, i, tmp_rates);
+		} else {
+			spin_unlock_bh(&wvif->tx_policy_cache.lock);
+		}
+	} while (i < ARRAY_SIZE(wvif->tx_policy_cache.cache));
+	return 0;
+}
+
+void wfx_tx_policy_upload_work(struct work_struct *work)
+{
+	struct wfx_vif *wvif =
+		container_of(work, struct wfx_vif, tx_policy_upload_work);
+
+	wfx_tx_policy_upload(wvif);
+	wfx_tx_unlock(wvif->wdev);
+}
+
+void wfx_tx_policy_init(struct wfx_vif *wvif)
+{
+	struct wfx_tx_policy_cache *cache = &wvif->tx_policy_cache;
+	int i;
+
+	memset(cache, 0, sizeof(*cache));
+
+	spin_lock_init(&cache->lock);
+	INIT_LIST_HEAD(&cache->used);
+	INIT_LIST_HEAD(&cache->free);
+
+	for (i = 0; i < ARRAY_SIZE(cache->cache); ++i)
+		list_add(&cache->cache[i].link, &cache->free);
+}
+
+/* Tx implementation */
+
+static bool wfx_is_action_back(struct ieee80211_hdr *hdr)
+{
+	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *)hdr;
+
+	if (!ieee80211_is_action(mgmt->frame_control))
+		return false;
+	if (mgmt->u.action.category != WLAN_CATEGORY_BACK)
+		return false;
+	return true;
+}
+
+static u8 wfx_tx_get_link_id(struct wfx_vif *wvif, struct ieee80211_sta *sta,
+			     struct ieee80211_hdr *hdr)
+{
+	struct wfx_sta_priv *sta_priv =
+		sta ? (struct wfx_sta_priv *)&sta->drv_priv : NULL;
+	const u8 *da = ieee80211_get_DA(hdr);
+
+	if (sta_priv && sta_priv->link_id)
+		return sta_priv->link_id;
+	if (wvif->vif->type != NL80211_IFTYPE_AP)
+		return 0;
+	if (is_multicast_ether_addr(da))
+		return 0;
+	return HIF_LINK_ID_NOT_ASSOCIATED;
+}
+
+static void wfx_tx_fixup_rates(struct ieee80211_tx_rate *rates)
+{
+	int i;
+	bool finished;
+
+	/* Firmware is not able to mix rates with different flags */
+	for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
+		if (rates[0].flags & IEEE80211_TX_RC_SHORT_GI)
+			rates[i].flags |= IEEE80211_TX_RC_SHORT_GI;
+		if (!(rates[0].flags & IEEE80211_TX_RC_SHORT_GI))
+			rates[i].flags &= ~IEEE80211_TX_RC_SHORT_GI;
+		if (!(rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS))
+			rates[i].flags &= ~IEEE80211_TX_RC_USE_RTS_CTS;
+	}
+
+	/* Sort rates and remove duplicates */
+	do {
+		finished = true;
+		for (i = 0; i < IEEE80211_TX_MAX_RATES - 1; i++) {
+			if (rates[i + 1].idx == rates[i].idx &&
+			    rates[i].idx != -1) {
+				rates[i].count += rates[i + 1].count;
+				if (rates[i].count > 15)
+					rates[i].count = 15;
+				rates[i + 1].idx = -1;
+				rates[i + 1].count = 0;
+
+				finished = false;
+			}
+			if (rates[i + 1].idx > rates[i].idx) {
+				swap(rates[i + 1], rates[i]);
+				finished = false;
+			}
+		}
+	} while (!finished);
+	/* Ensure that MCS0 or 1Mbps is present at the end of the retry list */
+	for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
+		if (rates[i].idx == 0)
+			break;
+		if (rates[i].idx == -1) {
+			rates[i].idx = 0;
+			rates[i].count = 8; /* == hw->max_rate_tries */
+			rates[i].flags = rates[i - 1].flags &
+					 IEEE80211_TX_RC_MCS;
+			break;
+		}
+	}
+	/* All retries use long GI */
+	for (i = 1; i < IEEE80211_TX_MAX_RATES; i++)
+		rates[i].flags &= ~IEEE80211_TX_RC_SHORT_GI;
+}
+
+static u8 wfx_tx_get_retry_policy_id(struct wfx_vif *wvif,
+				     struct ieee80211_tx_info *tx_info)
+{
+	bool tx_policy_renew = false;
+	u8 ret;
+
+	ret = wfx_tx_policy_get(wvif, tx_info->driver_rates, &tx_policy_renew);
+	if (ret == HIF_TX_RETRY_POLICY_INVALID)
+		dev_warn(wvif->wdev->dev, "unable to get a valid Tx policy");
+
+	if (tx_policy_renew) {
+		wfx_tx_lock(wvif->wdev);
+		if (!schedule_work(&wvif->tx_policy_upload_work))
+			wfx_tx_unlock(wvif->wdev);
+	}
+	return ret;
+}
+
+static int wfx_tx_get_frame_format(struct ieee80211_tx_info *tx_info)
+{
+	if (!(tx_info->driver_rates[0].flags & IEEE80211_TX_RC_MCS))
+		return HIF_FRAME_FORMAT_NON_HT;
+	else if (!(tx_info->driver_rates[0].flags & IEEE80211_TX_RC_GREEN_FIELD))
+		return HIF_FRAME_FORMAT_MIXED_FORMAT_HT;
+	else
+		return HIF_FRAME_FORMAT_GF_HT_11N;
+}
+
+static int wfx_tx_get_icv_len(struct ieee80211_key_conf *hw_key)
+{
+	int mic_space;
+
+	if (!hw_key)
+		return 0;
+	if (hw_key->cipher == WLAN_CIPHER_SUITE_AES_CMAC)
+		return 0;
+	mic_space = (hw_key->cipher == WLAN_CIPHER_SUITE_TKIP) ? 8 : 0;
+	return hw_key->icv_len + mic_space;
+}
+
+static int wfx_tx_inner(struct wfx_vif *wvif, struct ieee80211_sta *sta,
+			struct sk_buff *skb)
+{
+	struct wfx_hif_msg *hif_msg;
+	struct wfx_hif_req_tx *req;
+	struct wfx_tx_priv *tx_priv;
+	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
+	struct ieee80211_key_conf *hw_key = tx_info->control.hw_key;
+	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
+	int queue_id = skb_get_queue_mapping(skb);
+	size_t offset = (size_t)skb->data & 3;
+	int wmsg_len = sizeof(struct wfx_hif_msg) +
+			sizeof(struct wfx_hif_req_tx) + offset;
+
+	WARN(queue_id >= IEEE80211_NUM_ACS, "unsupported queue_id");
+	wfx_tx_fixup_rates(tx_info->driver_rates);
+
+	/* From now tx_info->control is unusable */
+	memset(tx_info->rate_driver_data, 0, sizeof(struct wfx_tx_priv));
+	/* Fill tx_priv */
+	tx_priv = (struct wfx_tx_priv *)tx_info->rate_driver_data;
+	tx_priv->icv_size = wfx_tx_get_icv_len(hw_key);
+
+	/* Fill hif_msg */
+	WARN(skb_headroom(skb) < wmsg_len, "not enough space in skb");
+	WARN(offset & 1, "attempt to transmit an unaligned frame");
+	skb_put(skb, tx_priv->icv_size);
+	skb_push(skb, wmsg_len);
+	memset(skb->data, 0, wmsg_len);
+	hif_msg = (struct wfx_hif_msg *)skb->data;
+	hif_msg->len = cpu_to_le16(skb->len);
+	hif_msg->id = HIF_REQ_ID_TX;
+	hif_msg->interface = wvif->id;
+	if (skb->len > le16_to_cpu(wvif->wdev->hw_caps.size_inp_ch_buf)) {
+		dev_warn(wvif->wdev->dev,
+			 "requested frame size (%d) is larger than maximum supported (%d)\n",
+			 skb->len, le16_to_cpu(wvif->wdev->hw_caps.size_inp_ch_buf));
+		skb_pull(skb, wmsg_len);
+		return -EIO;
+	}
+
+	/* Fill tx request */
+	req = (struct wfx_hif_req_tx *)hif_msg->body;
+	/* packet_id just need to be unique on device. 32bits are more than
+	 * necessary for that task, so we take advantage of it to add some extra
+	 * data for debug.
+	 */
+	req->packet_id = atomic_add_return(1, &wvif->wdev->packet_id) & 0xFFFF;
+	req->packet_id |= IEEE80211_SEQ_TO_SN(le16_to_cpu(hdr->seq_ctrl)) << 16;
+	req->packet_id |= queue_id << 28;
+
+	req->fc_offset = offset;
+	/* Queue index are inverted between firmware and Linux */
+	req->queue_id = 3 - queue_id;
+	req->peer_sta_id = wfx_tx_get_link_id(wvif, sta, hdr);
+	req->retry_policy_index = wfx_tx_get_retry_policy_id(wvif, tx_info);
+	req->frame_format = wfx_tx_get_frame_format(tx_info);
+	if (tx_info->driver_rates[0].flags & IEEE80211_TX_RC_SHORT_GI)
+		req->short_gi = 1;
+	if (tx_info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM)
+		req->after_dtim = 1;
+
+	/* Auxiliary operations */
+	wfx_tx_queues_put(wvif, skb);
+	if (tx_info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM)
+		schedule_work(&wvif->update_tim_work);
+	wfx_bh_request_tx(wvif->wdev);
+	return 0;
+}
+
+void wfx_tx(struct ieee80211_hw *hw, struct ieee80211_tx_control *control,
+	    struct sk_buff *skb)
+{
+	struct wfx_dev *wdev = hw->priv;
+	struct wfx_vif *wvif;
+	struct ieee80211_sta *sta = control ? control->sta : NULL;
+	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
+	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
+	size_t driver_data_room = sizeof_field(struct ieee80211_tx_info,
+					       rate_driver_data);
+
+	BUILD_BUG_ON_MSG(sizeof(struct wfx_tx_priv) > driver_data_room,
+			 "struct tx_priv is too large");
+	WARN(skb->next || skb->prev, "skb is already member of a list");
+	/* control.vif can be NULL for injected frames */
+	if (tx_info->control.vif)
+		wvif = (struct wfx_vif *)tx_info->control.vif->drv_priv;
+	else
+		wvif = wvif_iterate(wdev, NULL);
+	if (WARN_ON(!wvif))
+		goto drop;
+	/* Because of TX_AMPDU_SETUP_IN_HW, mac80211 does not try to send any
+	 * BlockAck session management frame. The check below exist just in case.
+	 */
+	if (wfx_is_action_back(hdr)) {
+		dev_info(wdev->dev, "drop BA action\n");
+		goto drop;
+	}
+	if (wfx_tx_inner(wvif, sta, skb))
+		goto drop;
+
+	return;
+
+drop:
+	ieee80211_tx_status_irqsafe(wdev->hw, skb);
+}
+
+static void wfx_skb_dtor(struct wfx_vif *wvif, struct sk_buff *skb)
+{
+	struct wfx_hif_msg *hif = (struct wfx_hif_msg *)skb->data;
+	struct wfx_hif_req_tx *req = (struct wfx_hif_req_tx *)hif->body;
+	unsigned int offset = sizeof(struct wfx_hif_msg) +
+			      sizeof(struct wfx_hif_req_tx) +
+			      req->fc_offset;
+
+	if (!wvif) {
+		pr_warn("vif associated with the skb does not exist anymore\n");
+		return;
+	}
+	wfx_tx_policy_put(wvif, req->retry_policy_index);
+	skb_pull(skb, offset);
+	ieee80211_tx_status_irqsafe(wvif->wdev->hw, skb);
+}
+
+static void wfx_tx_fill_rates(struct wfx_dev *wdev,
+			      struct ieee80211_tx_info *tx_info,
+			      const struct wfx_hif_cnf_tx *arg)
+{
+	struct ieee80211_tx_rate *rate;
+	int tx_count;
+	int i;
+
+	tx_count = arg->ack_failures;
+	if (!arg->status || arg->ack_failures)
+		tx_count += 1; /* Also report success */
+	for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
+		rate = &tx_info->status.rates[i];
+		if (rate->idx < 0)
+			break;
+		if (tx_count < rate->count &&
+		    arg->status == HIF_STATUS_TX_FAIL_RETRIES &&
+		    arg->ack_failures)
+			dev_dbg(wdev->dev, "all retries were not consumed: %d != %d\n",
+				rate->count, tx_count);
+		if (tx_count <= rate->count && tx_count &&
+		    arg->txed_rate != wfx_get_hw_rate(wdev, rate))
+			dev_dbg(wdev->dev, "inconsistent tx_info rates: %d != %d\n",
+				arg->txed_rate, wfx_get_hw_rate(wdev, rate));
+		if (tx_count > rate->count) {
+			tx_count -= rate->count;
+		} else if (!tx_count) {
+			rate->count = 0;
+			rate->idx = -1;
+		} else {
+			rate->count = tx_count;
+			tx_count = 0;
+		}
+	}
+	if (tx_count)
+		dev_dbg(wdev->dev, "%d more retries than expected\n", tx_count);
+}
+
+void wfx_tx_confirm_cb(struct wfx_dev *wdev, const struct wfx_hif_cnf_tx *arg)
+{
+	const struct wfx_tx_priv *tx_priv;
+	struct ieee80211_tx_info *tx_info;
+	struct wfx_vif *wvif;
+	struct sk_buff *skb;
+
+	skb = wfx_pending_get(wdev, arg->packet_id);
+	if (!skb) {
+		dev_warn(wdev->dev, "received unknown packet_id (%#.8x) from chip\n",
+			 arg->packet_id);
+		return;
+	}
+	tx_info = IEEE80211_SKB_CB(skb);
+	tx_priv = wfx_skb_tx_priv(skb);
+	wvif = wdev_to_wvif(wdev, ((struct wfx_hif_msg *)skb->data)->interface);
+	WARN_ON(!wvif);
+	if (!wvif)
+		return;
+
+	/* Note that wfx_pending_get_pkt_us_delay() get data from tx_info */
+	_trace_tx_stats(arg, skb, wfx_pending_get_pkt_us_delay(wdev, skb));
+	wfx_tx_fill_rates(wdev, tx_info, arg);
+	skb_trim(skb, skb->len - tx_priv->icv_size);
+
+	/* From now, you can touch to tx_info->status, but do not touch to
+	 * tx_priv anymore
+	 */
+	/* FIXME: use ieee80211_tx_info_clear_status() */
+	memset(tx_info->rate_driver_data, 0, sizeof(tx_info->rate_driver_data));
+	memset(tx_info->pad, 0, sizeof(tx_info->pad));
+
+	if (!arg->status) {
+		tx_info->status.tx_time =
+			le32_to_cpu(arg->media_delay) -
+			le32_to_cpu(arg->tx_queue_delay);
+		if (tx_info->flags & IEEE80211_TX_CTL_NO_ACK)
+			tx_info->flags |= IEEE80211_TX_STAT_NOACK_TRANSMITTED;
+		else
+			tx_info->flags |= IEEE80211_TX_STAT_ACK;
+	} else if (arg->status == HIF_STATUS_TX_FAIL_REQUEUE) {
+		WARN(!arg->requeue, "incoherent status and result_flags");
+		if (tx_info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM) {
+			wvif->after_dtim_tx_allowed = false; /* DTIM period elapsed */
+			schedule_work(&wvif->update_tim_work);
+		}
+		tx_info->flags |= IEEE80211_TX_STAT_TX_FILTERED;
+	}
+	wfx_skb_dtor(wvif, skb);
+}
+
+static void wfx_flush_vif(struct wfx_vif *wvif, u32 queues,
+			  struct sk_buff_head *dropped)
+{
+	struct wfx_queue *queue;
+	int i;
+
+	for (i = 0; i < IEEE80211_NUM_ACS; i++) {
+		if (!(BIT(i) & queues))
+			continue;
+		queue = &wvif->tx_queue[i];
+		if (dropped)
+			wfx_tx_queue_drop(wvif, queue, dropped);
+	}
+	if (wvif->wdev->chip_frozen)
+		return;
+	for (i = 0; i < IEEE80211_NUM_ACS; i++) {
+		if (!(BIT(i) & queues))
+			continue;
+		queue = &wvif->tx_queue[i];
+		if (wait_event_timeout(wvif->wdev->tx_dequeue,
+				       wfx_tx_queue_empty(wvif, queue),
+				       msecs_to_jiffies(1000)) <= 0)
+			dev_warn(wvif->wdev->dev,
+				 "frames queued while flushing tx queues?");
+	}
+}
+
+void wfx_flush(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
+	       u32 queues, bool drop)
+{
+	struct wfx_dev *wdev = hw->priv;
+	struct sk_buff_head dropped;
+	struct wfx_vif *wvif;
+	struct wfx_hif_msg *hif;
+	struct sk_buff *skb;
+
+	skb_queue_head_init(&dropped);
+	if (vif) {
+		wvif = (struct wfx_vif *)vif->drv_priv;
+		wfx_flush_vif(wvif, queues, drop ? &dropped : NULL);
+	} else {
+		wvif = NULL;
+		while ((wvif = wvif_iterate(wdev, wvif)) != NULL)
+			wfx_flush_vif(wvif, queues, drop ? &dropped : NULL);
+	}
+	wfx_tx_flush(wdev);
+	if (wdev->chip_frozen)
+		wfx_pending_drop(wdev, &dropped);
+	while ((skb = skb_dequeue(&dropped)) != NULL) {
+		hif = (struct wfx_hif_msg *)skb->data;
+		wvif = wdev_to_wvif(wdev, hif->interface);
+		ieee80211_tx_info_clear_status(IEEE80211_SKB_CB(skb));
+		wfx_skb_dtor(wvif, skb);
+	}
+}
diff --git a/drivers/net/wireless/silabs/wfx/data_tx.h b/drivers/net/wireless/silabs/wfx/data_tx.h
new file mode 100644
index 000000000000..040f731e62ae
--- /dev/null
+++ b/drivers/net/wireless/silabs/wfx/data_tx.h
@@ -0,0 +1,68 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Data transmitting implementation.
+ *
+ * Copyright (c) 2017-2020, Silicon Laboratories, Inc.
+ * Copyright (c) 2010, ST-Ericsson
+ */
+#ifndef WFX_DATA_TX_H
+#define WFX_DATA_TX_H
+
+#include <linux/list.h>
+#include <net/mac80211.h>
+
+#include "hif_api_cmd.h"
+#include "hif_api_mib.h"
+
+struct wfx_tx_priv;
+struct wfx_dev;
+struct wfx_vif;
+
+struct wfx_tx_policy {
+	struct list_head link;
+	int usage_count;
+	u8 rates[12];
+	bool uploaded;
+};
+
+struct wfx_tx_policy_cache {
+	struct wfx_tx_policy cache[HIF_TX_RETRY_POLICY_MAX];
+	/* FIXME: use a trees and drop hash from tx_policy */
+	struct list_head used;
+	struct list_head free;
+	spinlock_t lock;
+};
+
+struct wfx_tx_priv {
+	ktime_t xmit_timestamp;
+	unsigned char icv_size;
+};
+
+void wfx_tx_policy_init(struct wfx_vif *wvif);
+void wfx_tx_policy_upload_work(struct work_struct *work);
+
+void wfx_tx(struct ieee80211_hw *hw, struct ieee80211_tx_control *control,
+	    struct sk_buff *skb);
+void wfx_tx_confirm_cb(struct wfx_dev *wdev, const struct wfx_hif_cnf_tx *arg);
+void wfx_flush(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
+	       u32 queues, bool drop);
+
+static inline struct wfx_tx_priv *wfx_skb_tx_priv(struct sk_buff *skb)
+{
+	struct ieee80211_tx_info *tx_info;
+
+	if (!skb)
+		return NULL;
+	tx_info = IEEE80211_SKB_CB(skb);
+	return (struct wfx_tx_priv *)tx_info->rate_driver_data;
+}
+
+static inline struct wfx_hif_req_tx *wfx_skb_txreq(struct sk_buff *skb)
+{
+	struct wfx_hif_msg *hif = (struct wfx_hif_msg *)skb->data;
+	struct wfx_hif_req_tx *req = (struct wfx_hif_req_tx *)hif->body;
+
+	return req;
+}
+
+#endif
-- 
2.33.0