mt76: set txwi_size according to the driver value

Dynamically allocate txwi since new chipsets will use longer txwi
descriptors

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

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

@@ -296,12 +296,14 @@ mt76_dma_tx_queue_skb(struct mt76_dev *dev, enum mt76_txq_id qid,
 	struct mt76_txwi_cache *t;
 	struct sk_buff *iter;
 	dma_addr_t addr;
+	u8 *txwi;
 
 	t = mt76_get_txwi(dev);
 	if (!t) {
 		ieee80211_free_txskb(dev->hw, skb);
 		return -ENOMEM;
 	}
+	txwi = mt76_get_txwi_ptr(dev, t);
 
 	skb->prev = skb->next = NULL;
 	if (dev->drv->tx_aligned4_skbs)
@@ -331,11 +333,11 @@ mt76_dma_tx_queue_skb(struct mt76_dev *dev, enum mt76_txq_id qid,
 	}
 	tx_info.nbuf = n;
 
-	dma_sync_single_for_cpu(dev->dev, t->dma_addr, sizeof(t->txwi),
+	dma_sync_single_for_cpu(dev->dev, t->dma_addr, dev->drv->txwi_size,
 				DMA_TO_DEVICE);
-	ret = dev->drv->tx_prepare_skb(dev, &t->txwi, skb, qid, wcid, sta,
+	ret = dev->drv->tx_prepare_skb(dev, txwi, skb, qid, wcid, sta,
 				       &tx_info);
-	dma_sync_single_for_device(dev->dev, t->dma_addr, sizeof(t->txwi),
+	dma_sync_single_for_device(dev->dev, t->dma_addr, dev->drv->txwi_size,
 				   DMA_TO_DEVICE);
 	if (ret < 0)
 		goto unmap;

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

@@ -229,12 +229,10 @@ struct mt76_txq {
 };
 
 struct mt76_txwi_cache {
-	u32 txwi[8];
-	dma_addr_t dma_addr;
 	struct list_head list;
+	dma_addr_t dma_addr;
 };
 
-
 struct mt76_rx_tid {
 	struct rcu_head rcu_head;
 
@@ -617,6 +615,12 @@ void mt76_seq_puts_array(struct seq_file *file, const char *str,
 int mt76_eeprom_init(struct mt76_dev *dev, int len);
 void mt76_eeprom_override(struct mt76_dev *dev);
 
+static inline u8 *
+mt76_get_txwi_ptr(struct mt76_dev *dev, struct mt76_txwi_cache *t)
+{
+	return (u8 *)t - dev->drv->txwi_size;
+}
+
 /* increment with wrap-around */
 static inline int mt76_incr(int val, int size)
 {

drivers/net/wireless/mediatek/mt76/mt76x02_mac.c

@@ -770,6 +770,7 @@ void mt76x02_tx_complete_skb(struct mt76_dev *mdev, enum mt76_txq_id qid,
 {
 	struct mt76x02_dev *dev = container_of(mdev, struct mt76x02_dev, mt76);
 	struct mt76x02_txwi *txwi;
+	u8 *txwi_ptr;
 
 	if (!e->txwi) {
 		dev_kfree_skb_any(e->skb);
@@ -778,7 +779,8 @@ void mt76x02_tx_complete_skb(struct mt76_dev *mdev, enum mt76_txq_id qid,
 
 	mt76x02_mac_poll_tx_status(dev, false);
 
-	txwi = (struct mt76x02_txwi *) &e->txwi->txwi;
+	txwi_ptr = mt76_get_txwi_ptr(mdev, e->txwi);
+	txwi = (struct mt76x02_txwi *)txwi_ptr;
 	trace_mac_txdone_add(dev, txwi->wcid, txwi->pktid);
 
 	mt76_tx_complete_skb(mdev, e->skb);

drivers/net/wireless/mediatek/mt76/mt76x02_mmio.c

@@ -175,7 +175,6 @@ int mt76x02_dma_init(struct mt76x02_dev *dev)
 	struct mt76_queue *q;
 	void *status_fifo;
 
-	BUILD_BUG_ON(sizeof(t->txwi) < sizeof(struct mt76x02_txwi));
 	BUILD_BUG_ON(sizeof(struct mt76x02_rxwi) > MT_RX_HEADROOM);
 
 	fifo_size = roundup_pow_of_two(32 * sizeof(struct mt76x02_tx_status));

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

@@ -21,15 +21,17 @@ mt76_alloc_txwi(struct mt76_dev *dev)
 {
 	struct mt76_txwi_cache *t;
 	dma_addr_t addr;
+	u8 *txwi;
 	int size;
 
-	size = (sizeof(*t) + L1_CACHE_BYTES - 1) & ~(L1_CACHE_BYTES - 1);
-	t = devm_kzalloc(dev->dev, size, GFP_ATOMIC);
-	if (!t)
+	size = L1_CACHE_ALIGN(dev->drv->txwi_size + sizeof(*t));
+	txwi = devm_kzalloc(dev->dev, size, GFP_ATOMIC);
+	if (!txwi)
 		return NULL;
 
-	addr = dma_map_single(dev->dev, &t->txwi, sizeof(t->txwi),
+	addr = dma_map_single(dev->dev, txwi, dev->drv->txwi_size,
 			      DMA_TO_DEVICE);
+	t = (struct mt76_txwi_cache *)(txwi + dev->drv->txwi_size);
 	t->dma_addr = addr;
 
 	return t;
@@ -78,7 +80,7 @@ void mt76_tx_free(struct mt76_dev *dev)
 	struct mt76_txwi_cache *t;
 
 	while ((t = __mt76_get_txwi(dev)) != NULL)
-		dma_unmap_single(dev->dev, t->dma_addr, sizeof(t->txwi),
+		dma_unmap_single(dev->dev, t->dma_addr, dev->drv->txwi_size,
 				 DMA_TO_DEVICE);
 }