mt76: drop MCU header size from buffer size in __mt76_mcu_send_firmware

Each firmware piece with mt7915 and mt7921 do not have the MCU header to
reroute the packet to the internal RAM. So we do not need to consider the
MCU header size in __mt76_mcu_send_firmware.
Move the MCU header overhead calculation to mt76_mcu_send_firmware (for
older chipsets)

Fixes: e57b7901 ("mt76: add mac80211 driver for MT7915 PCIe-based chipsets")
Fixes: 1c099ab4 ("mt76: mt7921: add MCU support")
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

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

@@ -112,7 +112,7 @@ int __mt76_mcu_send_firmware(struct mt76_dev *dev, int cmd, const void *data,
 	int err, cur_len;
 
 	while (len > 0) {
-		cur_len = min_t(int, max_len - dev->mcu_ops->headroom, len);
+		cur_len = min_t(int, max_len, len);
 
 		err = mt76_mcu_send_msg(dev, cmd, data, cur_len, false);
 		if (err)

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

@@ -1264,7 +1264,9 @@ static inline int
 mt76_mcu_send_firmware(struct mt76_dev *dev, int cmd, const void *data,
 		       int len)
 {
-	return __mt76_mcu_send_firmware(dev, cmd, data, len, 4096);
+	int max_len = 4096 - dev->mcu_ops->headroom;
+
+	return __mt76_mcu_send_firmware(dev, cmd, data, len, max_len);
 }
 
 static inline int

drivers/net/wireless/mediatek/mt76/mt7915/mcu.c

@@ -2648,8 +2648,8 @@ static int mt7915_load_patch(struct mt7915_dev *dev)
 			goto out;
 		}
 
-		ret = mt76_mcu_send_firmware(&dev->mt76, MCU_CMD(FW_SCATTER),
-					     dl, len);
+		ret = __mt76_mcu_send_firmware(&dev->mt76, MCU_CMD(FW_SCATTER),
+					       dl, len, 4096);
 		if (ret) {
 			dev_err(dev->mt76.dev, "Failed to send patch\n");
 			goto out;
@@ -2717,8 +2717,8 @@ mt7915_mcu_send_ram_firmware(struct mt7915_dev *dev,
 			return err;
 		}
 
-		err = mt76_mcu_send_firmware(&dev->mt76, MCU_CMD(FW_SCATTER),
-					     data + offset, len);
+		err = __mt76_mcu_send_firmware(&dev->mt76, MCU_CMD(FW_SCATTER),
+					       data + offset, len, 4096);
 		if (err) {
 			dev_err(dev->mt76.dev, "Failed to send firmware.\n");
 			return err;