[PATCH net v4 5/7] net: stmmac: dwmac4: Use the correct bufzise when the len is exactly 8K

[Maxime Chevallier <maxime.chevallier@bootlin.com>]

DMA bufsize selection isn't made on the MTU but the actual frame length,
so including the L2 header. On DWMAC4, if the len is exactly BUF_SIZE_8KiB,
the next larger size is incorrectly selected.

Lets fix the comparison and while at it, rename the parameter from len
to mtu.

Fixes: c3efed5ad1b0 ("net: stmmac: Enable dwmac4 jumbo frame more than 8KiB").
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
---
 drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c | 4 ++--
 drivers/net/ethernet/stmicro/stmmac/hwif.h         | 2 +-
 drivers/net/ethernet/stmicro/stmmac/ring_mode.c    | 4 ++--
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c
index 2994df41ec2c..c6a8f8d73501 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c
@@ -474,11 +474,11 @@ static void dwmac4_set_sarc(struct dma_desc *p, u32 sarc_type)
 					  sarc_type));
 }
 
-static int set_16kib_bfsize(int mtu)
+static int set_16kib_bfsize(int len)
 {
 	int ret = 0;
 
-	if (unlikely(mtu >= BUF_SIZE_8KiB))
+	if (unlikely(len > BUF_SIZE_8KiB))
 		ret = BUF_SIZE_16KiB;
 	return ret;
 }
diff --git a/drivers/net/ethernet/stmicro/stmmac/hwif.h b/drivers/net/ethernet/stmicro/stmmac/hwif.h
index 04dafec021b4..de7aa6d28148 100644
--- a/drivers/net/ethernet/stmicro/stmmac/hwif.h
+++ b/drivers/net/ethernet/stmicro/stmmac/hwif.h
@@ -540,7 +540,7 @@ struct stmmac_mode_ops {
 	bool (*is_jumbo_frm)(unsigned int len, bool enh_desc);
 	int (*jumbo_frm)(struct stmmac_tx_queue *tx_q, struct sk_buff *skb,
 			 int csum);
-	int (*set_16kib_bfsize)(int mtu);
+	int (*set_16kib_bfsize)(int len);
 	void (*init_desc3)(struct dma_desc *p);
 	void (*refill_desc3)(struct stmmac_rx_queue *rx_q, struct dma_desc *p);
 	void (*clean_desc3)(struct stmmac_tx_queue *tx_q, struct dma_desc *p);
diff --git a/drivers/net/ethernet/stmicro/stmmac/ring_mode.c b/drivers/net/ethernet/stmicro/stmmac/ring_mode.c
index f7949419eb9f..d2f0c321661d 100644
--- a/drivers/net/ethernet/stmicro/stmmac/ring_mode.c
+++ b/drivers/net/ethernet/stmicro/stmmac/ring_mode.c
@@ -124,10 +124,10 @@ static void clean_desc3(struct stmmac_tx_queue *tx_q, struct dma_desc *p)
 		p->des3 = 0;
 }
 
-static int set_16kib_bfsize(int mtu)
+static int set_16kib_bfsize(int len)
 {
 	int ret = 0;
-	if (unlikely(mtu > BUF_SIZE_8KiB))
+	if (unlikely(len > BUF_SIZE_8KiB))
 		ret = BUF_SIZE_16KiB;
 	return ret;
 }
-- 
2.55.0