net: stmmac: Correct byte order of perfect_match

[ Upstream commit e9dbeba ]

The perfect_match parameter of the update_vlan_hash operation is __le16,
and is correctly converted from host byte-order in the lone caller,
stmmac_vlan_update().

However, the implementations of this caller, dwxgmac2_update_vlan_hash()
and dwxgmac2_update_vlan_hash(), both treat this parameter as host byte
order, using the following pattern:

	u32 value = ...
	...
	writel(value | perfect_match, ...);

This is not correct because both:
1) value is host byte order; and
2) writel expects a host byte order value as it's first argument

I believe that this will break on big endian systems. And I expect it
has gone unnoticed by only being exercised on little endian systems.

The approach taken by this patch is to update the callback, and it's
caller to simply use a host byte order value.

Flagged by Sparse.
Compile tested only.

Fixes: c7ab0b8 ("net: stmmac: Fallback to VLAN Perfect filtering if HASH is not available")
Signed-off-by: Simon Horman <horms@kernel.org>
Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Author: horms

drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c

@@ -982,7 +982,7 @@ static void dwmac4_set_mac_loopback(void __iomem *ioaddr, bool enable)
 }
 
 static void dwmac4_update_vlan_hash(struct mac_device_info *hw, u32 hash,
-				    __le16 perfect_match, bool is_double)
+				    u16 perfect_match, bool is_double)
 {
 	void __iomem *ioaddr = hw->pcsr;
 	u32 value;

drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c

@@ -615,7 +615,7 @@ static int dwxgmac2_rss_configure(struct mac_device_info *hw,
 }
 
 static void dwxgmac2_update_vlan_hash(struct mac_device_info *hw, u32 hash,
-				      __le16 perfect_match, bool is_double)
+				      u16 perfect_match, bool is_double)
 {
 	void __iomem *ioaddr = hw->pcsr;
 

drivers/net/ethernet/stmicro/stmmac/hwif.h

@@ -394,7 +394,7 @@ struct stmmac_ops {
 			     struct stmmac_rss *cfg, u32 num_rxq);
 	/* VLAN */
 	void (*update_vlan_hash)(struct mac_device_info *hw, u32 hash,
-				 __le16 perfect_match, bool is_double);
+				 u16 perfect_match, bool is_double);
 	void (*enable_vlan)(struct mac_device_info *hw, u32 type);
 	void (*rx_hw_vlan)(struct mac_device_info *hw, struct dma_desc *rx_desc,
 			   struct sk_buff *skb);

drivers/net/ethernet/stmicro/stmmac/stmmac_main.c

@@ -6640,7 +6640,7 @@ static u32 stmmac_vid_crc32_le(__le16 vid_le)
 static int stmmac_vlan_update(struct stmmac_priv *priv, bool is_double)
 {
 	u32 crc, hash = 0;
-	__le16 pmatch = 0;
+	u16 pmatch = 0;
 	int count = 0;
 	u16 vid = 0;
 
@@ -6655,7 +6655,7 @@ static int stmmac_vlan_update(struct stmmac_priv *priv, bool is_double)
 		if (count > 2) /* VID = 0 always passes filter */
 			return -EOPNOTSUPP;
 
-		pmatch = cpu_to_le16(vid);
+		pmatch = vid;
 		hash = 0;
 	}