Subject: [PATCH 19/19] net: stmmac: dwmac-sunxi: Provide TX and RX fifo sizes

From: Florian Fainelli <[email-masked]>
Date: Tue, 14 Apr 2020 15:39:52 -0700

[ Upstream commit 806fd188ce2a4f8b587e83e73c478e6484fbfa55 ]

After commit bfcb813203e619a8960a819bf533ad2a108d8105 ("net: dsa:
configure the MTU for switch ports") my Lamobo R1 platform which uses
an allwinner,sun7i-a20-gmac compatible Ethernet MAC started to fail
by rejecting a MTU of 1536. The reason for that is that the DMA
capabilities are not readable on this version of the IP, and there
is also no 'tx-fifo-depth' property being provided in Device Tree. The
property is documented as optional, and is not provided.

Chen-Yu indicated that the FIFO sizes are 4KB for TX and 16KB for RX, so
provide these values through platform data as an immediate fix until
various Device Tree sources get updated accordingly.

Fixes: eaf4fac47807 ("net: stmmac: Do not accept invalid MTU values")
Suggested-by: Chen-Yu Tsai <[email-masked]>
Signed-off-by: Florian Fainelli <[email-masked]>
Acked-by: Chen-Yu Tsai <[email-masked]>
Signed-off-by: David S. Miller <[email-masked]>
---
 drivers/net/ethernet/stmicro/stmmac/dwmac-sunxi.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-sunxi.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-sunxi.c
index 7d40760e9ba8..0e1ca2cba3c7 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-sunxi.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-sunxi.c
@@ -150,6 +150,8 @@ static int sun7i_gmac_probe(struct platform_device *pdev)
 	plat_dat->init = sun7i_gmac_init;
 	plat_dat->exit = sun7i_gmac_exit;
 	plat_dat->fix_mac_speed = sun7i_fix_speed;
+	plat_dat->tx_fifo_size = 4096;
+	plat_dat->rx_fifo_size = 16384;
 
 	ret = sun7i_gmac_init(pdev, plat_dat->bsp_priv);
 	if (ret)
-- 
2.20.1