mt76: move pad estimation out of mt76_skb_adjust_pad

Move frame pad computation out of mt76_skb_adjust_pad routine.
This is a preliminary patch to introduce sdio tx aggregation.
Tested-by: Sean Wang <sean.wang@mediatek.com>
Co-developed-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

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

@@ -1043,7 +1043,7 @@ mt76u_bulk_msg(struct mt76_dev *dev, void *data, int len, int *actual_len,
 	return usb_bulk_msg(udev, pipe, data, len, actual_len, timeout);
 }
 
-int mt76_skb_adjust_pad(struct sk_buff *skb);
+int mt76_skb_adjust_pad(struct sk_buff *skb, int pad);
 int mt76u_vendor_request(struct mt76_dev *dev, u8 req,
 			 u8 req_type, u16 val, u16 offset,
 			 void *buf, size_t len);

drivers/net/wireless/mediatek/mt76/mt7615/sdio_txrx.c

@@ -190,6 +190,8 @@ static int mt7663s_tx_run_queue(struct mt76_dev *dev, enum mt76_txq_id qid)
 					  &ple_sz))
 			break;
 
+		__skb_put_zero(e->skb, 4);
+
 		err = __mt7663s_xmit_queue(dev, e->skb->data, e->skb->len);
 		if (err)
 			return err;

drivers/net/wireless/mediatek/mt76/mt7615/usb_mcu.c

@@ -18,8 +18,7 @@ mt7663u_mcu_send_message(struct mt76_dev *mdev, struct sk_buff *skb,
 			 int cmd, bool wait_resp)
 {
 	struct mt7615_dev *dev = container_of(mdev, struct mt7615_dev, mt76);
-	int ret, seq, ep;
-	u32 len;
+	int ret, seq, ep, len, pad;
 
 	mutex_lock(&mdev->mcu.mutex);
 
@@ -31,7 +30,8 @@ mt7663u_mcu_send_message(struct mt76_dev *mdev, struct sk_buff *skb,
 
 	len = skb->len;
 	put_unaligned_le32(len, skb_push(skb, sizeof(len)));
-	ret = mt76_skb_adjust_pad(skb);
+	pad = round_up(skb->len, 4) + 4 - skb->len;
+	ret = mt76_skb_adjust_pad(skb, pad);
 	if (ret < 0)
 		goto out;
 

drivers/net/wireless/mediatek/mt76/mt7615/usb_sdio.c

@@ -247,6 +247,7 @@ int mt7663_usb_sdio_tx_prepare_skb(struct mt76_dev *mdev, void *txwi_ptr,
 	struct mt7615_dev *dev = container_of(mdev, struct mt7615_dev, mt76);
 	struct sk_buff *skb = tx_info->skb;
 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+	int pad;
 
 	if ((info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE) &&
 	    !msta->rate_probe) {
@@ -262,9 +263,12 @@ int mt7663_usb_sdio_tx_prepare_skb(struct mt76_dev *mdev, void *txwi_ptr,
 		u32 len = skb->len;
 
 		put_unaligned_le32(len, skb_push(skb, sizeof(len)));
+		pad = round_up(skb->len, 4) + 4 - skb->len;
+	} else {
+		pad = round_up(skb->len, 4) - skb->len;
 	}
 
-	return mt76_skb_adjust_pad(skb);
+	return mt76_skb_adjust_pad(skb, pad);
 }
 EXPORT_SYMBOL_GPL(mt7663_usb_sdio_tx_prepare_skb);
 

drivers/net/wireless/mediatek/mt76/mt76x02_usb_core.c

@@ -45,7 +45,7 @@ EXPORT_SYMBOL_GPL(mt76x02u_mac_start);
 
 int mt76x02u_skb_dma_info(struct sk_buff *skb, int port, u32 flags)
 {
-	u32 info;
+	u32 info, pad;
 
 	/* Buffer layout:
 	 *	|   4B   | xfer len |      pad       |  4B  |
@@ -57,7 +57,8 @@ int mt76x02u_skb_dma_info(struct sk_buff *skb, int port, u32 flags)
 	       FIELD_PREP(MT_TXD_INFO_DPORT, port) | flags;
 	put_unaligned_le32(info, skb_push(skb, sizeof(info)));
 
-	return mt76_skb_adjust_pad(skb);
+	pad = round_up(skb->len, 4) + 4 - skb->len;
+	return mt76_skb_adjust_pad(skb, pad);
 }
 
 int mt76x02u_tx_prepare_skb(struct mt76_dev *mdev, void *data,

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

@@ -226,12 +226,13 @@ mt76s_tx_queue_skb_raw(struct mt76_dev *dev, enum mt76_txq_id qid,
 		       struct sk_buff *skb, u32 tx_info)
 {
 	struct mt76_queue *q = dev->q_tx[qid];
-	int ret = -ENOSPC, len = skb->len;
+	int ret = -ENOSPC, len = skb->len, pad;
 
 	if (q->queued == q->ndesc)
 		goto error;
 
-	ret = mt76_skb_adjust_pad(skb);
+	pad = round_up(skb->len, 4) - skb->len;
+	ret = mt76_skb_adjust_pad(skb, pad);
 	if (ret)
 		goto error;
 

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

@@ -589,13 +589,9 @@ u8 mt76_ac_to_hwq(u8 ac)
 }
 EXPORT_SYMBOL_GPL(mt76_ac_to_hwq);
 
-int mt76_skb_adjust_pad(struct sk_buff *skb)
+int mt76_skb_adjust_pad(struct sk_buff *skb, int pad)
 {
 	struct sk_buff *iter, *last = skb;
-	u32 pad;
-
-	/* Add zero pad of 4 - 7 bytes */
-	pad = round_up(skb->len, 4) + 4 - skb->len;
 
 	/* First packet of a A-MSDU burst keeps track of the whole burst
 	 * length, need to update length of it and the last packet.