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From:   Corentin Labbe <clabbe@baylibre.com>
To:     alexandre.torgue@st.com, davem@davemloft.net,
        jernej.skrabec@siol.net, joabreu@synopsys.com,
        marek.belisko@gmail.com, mripard@kernel.org,
        peppe.cavallaro@st.com, wens@csie.org
Cc:     linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        netdev@vger.kernel.org, Corentin Labbe <clabbe@baylibre.com>
Subject: [PATCH] net: stmmac: dwmac-sun8i: Provide TX and RX fifo sizes
Date:   Fri, 19 Mar 2021 13:44:22 +0000
Message-Id: <20210319134422.9351-1-clabbe@baylibre.com>
Precedence: bulk

MTU cannot be changed on dwmac-sun8i. (ip link set eth0 mtu xxx returning EINVAL)
This is due to tx_fifo_size being 0, since this value is used to compute valid
MTU range.
Like dwmac-sunxi (with commit 806fd188ce2a ("net: stmmac: dwmac-sunxi: Provide TX and RX fifo sizes"))
dwmac-sun8i need to have tx and rx fifo sizes set.
I have used values from datasheets.
After this patch, setting a non-default MTU (like 1000) value works and network is still useable.

Tested-on: sun8i-h3-orangepi-pc
Tested-on: sun8i-r40-bananapi-m2-ultra
Tested-on: sun50i-a64-bananapi-m64
Tested-on: sun50i-h5-nanopi-neo-plus2
Tested-on: sun50i-h6-pine-h64
Fixes: 9f93ac8d408 ("net-next: stmmac: Add dwmac-sun8i")
Reported-by: Belisko Marek <marek.belisko@gmail.com>
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
---
 drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c
index 6b75cf2603ff..e62efd166ec8 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c
@@ -1214,6 +1214,8 @@ static int sun8i_dwmac_probe(struct platform_device *pdev)
 	plat_dat->init = sun8i_dwmac_init;
 	plat_dat->exit = sun8i_dwmac_exit;
 	plat_dat->setup = sun8i_dwmac_setup;
+	plat_dat->tx_fifo_size = 4096;
+	plat_dat->rx_fifo_size = 16384;
 
 	ret = sun8i_dwmac_set_syscon(&pdev->dev, plat_dat);
 	if (ret)
-- 
2.26.2