wifi: mt76: introduce rxwi and rx token utility routines

This is a preliminary patch to introduce WED RX support for mt7915.
Tested-by: Daniel Golle <daniel@makrotopia.org>
Co-developed-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Sujuan Chen <sujuan.chen@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/dma.c

@@ -59,6 +59,19 @@ mt76_alloc_txwi(struct mt76_dev *dev)
 	return t;
 }
 
+static struct mt76_txwi_cache *
+mt76_alloc_rxwi(struct mt76_dev *dev)
+{
+	struct mt76_txwi_cache *t;
+
+	t = kzalloc(L1_CACHE_ALIGN(sizeof(*t)), GFP_ATOMIC);
+	if (!t)
+		return NULL;
+
+	t->ptr = NULL;
+	return t;
+}
+
 static struct mt76_txwi_cache *
 __mt76_get_txwi(struct mt76_dev *dev)
 {
@@ -75,6 +88,22 @@ __mt76_get_txwi(struct mt76_dev *dev)
 	return t;
 }
 
+static struct mt76_txwi_cache *
+__mt76_get_rxwi(struct mt76_dev *dev)
+{
+	struct mt76_txwi_cache *t = NULL;
+
+	spin_lock(&dev->wed_lock);
+	if (!list_empty(&dev->rxwi_cache)) {
+		t = list_first_entry(&dev->rxwi_cache, struct mt76_txwi_cache,
+				     list);
+		list_del(&t->list);
+	}
+	spin_unlock(&dev->wed_lock);
+
+	return t;
+}
+
 static struct mt76_txwi_cache *
 mt76_get_txwi(struct mt76_dev *dev)
 {
@@ -86,6 +115,18 @@ mt76_get_txwi(struct mt76_dev *dev)
 	return mt76_alloc_txwi(dev);
 }
 
+struct mt76_txwi_cache *
+mt76_get_rxwi(struct mt76_dev *dev)
+{
+	struct mt76_txwi_cache *t = __mt76_get_rxwi(dev);
+
+	if (t)
+		return t;
+
+	return mt76_alloc_rxwi(dev);
+}
+EXPORT_SYMBOL_GPL(mt76_get_rxwi);
+
 void
 mt76_put_txwi(struct mt76_dev *dev, struct mt76_txwi_cache *t)
 {
@@ -98,6 +139,18 @@ mt76_put_txwi(struct mt76_dev *dev, struct mt76_txwi_cache *t)
 }
 EXPORT_SYMBOL_GPL(mt76_put_txwi);
 
+void
+mt76_put_rxwi(struct mt76_dev *dev, struct mt76_txwi_cache *t)
+{
+	if (!t)
+		return;
+
+	spin_lock(&dev->wed_lock);
+	list_add(&t->list, &dev->rxwi_cache);
+	spin_unlock(&dev->wed_lock);
+}
+EXPORT_SYMBOL_GPL(mt76_put_rxwi);
+
 static void
 mt76_free_pending_txwi(struct mt76_dev *dev)
 {
@@ -112,6 +165,20 @@ mt76_free_pending_txwi(struct mt76_dev *dev)
 	local_bh_enable();
 }
 
+static void
+mt76_free_pending_rxwi(struct mt76_dev *dev)
+{
+	struct mt76_txwi_cache *t;
+
+	local_bh_disable();
+	while ((t = __mt76_get_rxwi(dev)) != NULL) {
+		if (t->ptr)
+			skb_free_frag(t->ptr);
+		kfree(t);
+	}
+	local_bh_enable();
+}
+
 static void
 mt76_dma_sync_idx(struct mt76_dev *dev, struct mt76_queue *q)
 {
@@ -808,6 +875,7 @@ void mt76_dma_cleanup(struct mt76_dev *dev)
 	}
 
 	mt76_free_pending_txwi(dev);
+	mt76_free_pending_rxwi(dev);
 
 	if (mtk_wed_device_active(&dev->mmio.wed))
 		mtk_wed_device_detach(&dev->mmio.wed);

drivers/net/wireless/mediatek/mt76/dma.h

@@ -15,6 +15,14 @@
 #define MT_DMA_CTL_SD_LEN0		GENMASK(29, 16)
 #define MT_DMA_CTL_LAST_SEC0		BIT(30)
 #define MT_DMA_CTL_DMA_DONE		BIT(31)
+#define MT_DMA_CTL_TO_HOST		BIT(8)
+#define MT_DMA_CTL_TO_HOST_A		BIT(12)
+#define MT_DMA_CTL_DROP			BIT(14)
+#define MT_DMA_CTL_TOKEN		GENMASK(31, 16)
+
+#define MT_DMA_PPE_CPU_REASON		GENMASK(15, 11)
+#define MT_DMA_PPE_ENTRY		GENMASK(30, 16)
+#define MT_DMA_INFO_PPE_VLD		BIT(31)
 
 #define MT_DMA_HDR_LEN			4
 #define MT_RX_INFO_LEN			4

drivers/net/wireless/mediatek/mt76/mac80211.c

@@ -572,6 +572,7 @@ mt76_alloc_device(struct device *pdev, unsigned int size,
 	spin_lock_init(&dev->lock);
 	spin_lock_init(&dev->cc_lock);
 	spin_lock_init(&dev->status_lock);
+	spin_lock_init(&dev->wed_lock);
 	mutex_init(&dev->mutex);
 	init_waitqueue_head(&dev->tx_wait);
 
@@ -594,9 +595,13 @@ mt76_alloc_device(struct device *pdev, unsigned int size,
 	spin_lock_init(&dev->token_lock);
 	idr_init(&dev->token);
 
+	spin_lock_init(&dev->rx_token_lock);
+	idr_init(&dev->rx_token);
+
 	INIT_LIST_HEAD(&dev->wcid_list);
 
 	INIT_LIST_HEAD(&dev->txwi_cache);
+	INIT_LIST_HEAD(&dev->rxwi_cache);
 	dev->token_size = dev->drv->token_size;
 
 	for (i = 0; i < ARRAY_SIZE(dev->q_rx); i++)

drivers/net/wireless/mediatek/mt76/mt76.h

@@ -339,7 +339,10 @@ struct mt76_txwi_cache {
 	struct list_head list;
 	dma_addr_t dma_addr;
 
-	struct sk_buff *skb;
+	union {
+		struct sk_buff *skb;
+		void *ptr;
+	};
 };
 
 struct mt76_rx_tid {
@@ -728,6 +731,7 @@ struct mt76_dev {
 
 	struct ieee80211_hw *hw;
 
+	spinlock_t wed_lock;
 	spinlock_t lock;
 	spinlock_t cc_lock;
 
@@ -754,6 +758,7 @@ struct mt76_dev {
 	struct sk_buff_head rx_skb[__MT_RXQ_MAX];
 
 	struct list_head txwi_cache;
+	struct list_head rxwi_cache;
 	struct mt76_queue *q_mcu[__MT_MCUQ_MAX];
 	struct mt76_queue q_rx[__MT_RXQ_MAX];
 	const struct mt76_queue_ops *queue_ops;
@@ -768,6 +773,10 @@ struct mt76_dev {
 	u16 token_count;
 	u16 token_size;
 
+	spinlock_t rx_token_lock;
+	struct idr rx_token;
+	u16 rx_token_size;
+
 	wait_queue_head_t tx_wait;
 	/* spinclock used to protect wcid pktid linked list */
 	spinlock_t status_lock;
@@ -1247,6 +1256,8 @@ mt76_tx_status_get_hw(struct mt76_dev *dev, struct sk_buff *skb)
 }
 
 void mt76_put_txwi(struct mt76_dev *dev, struct mt76_txwi_cache *t);
+void mt76_put_rxwi(struct mt76_dev *dev, struct mt76_txwi_cache *t);
+struct mt76_txwi_cache *mt76_get_rxwi(struct mt76_dev *dev);
 void mt76_rx_complete(struct mt76_dev *dev, struct sk_buff_head *frames,
 		      struct napi_struct *napi);
 void mt76_rx_poll_complete(struct mt76_dev *dev, enum mt76_rxq_id q,
@@ -1391,6 +1402,9 @@ struct mt76_txwi_cache *
 mt76_token_release(struct mt76_dev *dev, int token, bool *wake);
 int mt76_token_consume(struct mt76_dev *dev, struct mt76_txwi_cache **ptxwi);
 void __mt76_set_tx_blocked(struct mt76_dev *dev, bool blocked);
+struct mt76_txwi_cache *mt76_rx_token_release(struct mt76_dev *dev, int token);
+int mt76_rx_token_consume(struct mt76_dev *dev, void *ptr,
+			  struct mt76_txwi_cache *r, dma_addr_t phys);
 
 static inline void mt76_set_tx_blocked(struct mt76_dev *dev, bool blocked)
 {

drivers/net/wireless/mediatek/mt76/tx.c

@@ -756,6 +756,23 @@ int mt76_token_consume(struct mt76_dev *dev, struct mt76_txwi_cache **ptxwi)
 }
 EXPORT_SYMBOL_GPL(mt76_token_consume);
 
+int mt76_rx_token_consume(struct mt76_dev *dev, void *ptr,
+			  struct mt76_txwi_cache *t, dma_addr_t phys)
+{
+	int token;
+
+	spin_lock_bh(&dev->rx_token_lock);
+	token = idr_alloc(&dev->rx_token, t, 0, dev->rx_token_size,
+			  GFP_ATOMIC);
+	spin_unlock_bh(&dev->rx_token_lock);
+
+	t->ptr = ptr;
+	t->dma_addr = phys;
+
+	return token;
+}
+EXPORT_SYMBOL_GPL(mt76_rx_token_consume);
+
 struct mt76_txwi_cache *
 mt76_token_release(struct mt76_dev *dev, int token, bool *wake)
 {
@@ -784,3 +801,16 @@ mt76_token_release(struct mt76_dev *dev, int token, bool *wake)
 	return txwi;
 }
 EXPORT_SYMBOL_GPL(mt76_token_release);
+
+struct mt76_txwi_cache *
+mt76_rx_token_release(struct mt76_dev *dev, int token)
+{
+	struct mt76_txwi_cache *t;
+
+	spin_lock_bh(&dev->rx_token_lock);
+	t = idr_remove(&dev->rx_token, token);
+	spin_unlock_bh(&dev->rx_token_lock);
+
+	return t;
+}
+EXPORT_SYMBOL_GPL(mt76_rx_token_release);