From: Felix Fietkau <nbd@nbd.name>
Date: Wed, 26 Aug 2020 16:59:41 +0200
Subject: [PATCH] net: ethernet: mtk_eth_soc: increase DMA ring sizes

256 descriptors is not enough for multi-gigabit traffic under load on MT7622.
Bump it to 512 to improve performance

Signed-off-by: Felix Fietkau <nbd@nbd.name>
---

--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.h
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
@@ -19,7 +19,7 @@
 #define MTK_QDMA_PAGE_SIZE	2048
 #define	MTK_MAX_RX_LENGTH	1536
 #define MTK_TX_DMA_BUF_LEN	0x3fff
-#define MTK_DMA_SIZE		256
+#define MTK_DMA_SIZE		512
 #define MTK_NAPI_WEIGHT		64
 #define MTK_MAC_COUNT		2
 #define MTK_RX_ETH_HLEN		(VLAN_ETH_HLEN + VLAN_HLEN + ETH_FCS_LEN)