From: Martin Blumenstingl martin.blumenstingl@googlemail.com
[ Upstream commit 29f0023d01f063feacfc404f0446905aee4f82ee ]
According to the Odroid-C1+ schematics the Ethernet TXD1 signal is routed to GPIOH_5 and the TXD0 signal is routed to GPIOH_6. The public S805 datasheet shows that TXD0 can be routed to DIF_2_P and TXD1 can be routed to DIF_2_N instead.
The pin groups eth_txd0_0 (GPIOH_6) and eth_txd0_1 (DIF_2_P) are both configured as Ethernet TXD0 and TXD1 data lines in meson8b.dtsi. At the same time eth_txd1_0 (GPIOH_5) and eth_txd1_1 (DIF_2_N) are configured as TXD0 and TXD1 data lines as well. This results in a bad Ethernet receive performance. Presumably this is due to the eth_txd0 and eth_txd1 signal being routed to the wrong pins. As a result of that data can only be transmitted on eth_txd2 and eth_txd3. However, I have no scope to fully confirm this assumption.
The vendor u-boot sources for Odroid-C1 use the following Ethernet pinmux configuration: SET_CBUS_REG_MASK(PERIPHS_PIN_MUX_6, 0x3f4f); SET_CBUS_REG_MASK(PERIPHS_PIN_MUX_7, 0xf00000); This translates to the following pin groups in the mainline kernel: - register 6 bit 0: eth_rxd1 (DIF_0_P) - register 6 bit 1: eth_rxd0 (DIF_0_N) - register 6 bit 2: eth_rx_dv (DIF_1_P) - register 6 bit 3: eth_rx_clk (DIF_1_N) - register 6 bit 6: eth_tx_en (DIF_3_P) - register 6 bit 8: eth_ref_clk (DIF_3_N) - register 6 bit 9: eth_mdc (DIF_4_P) - register 6 bit 10: eth_mdio_en (DIF_4_N) - register 6 bit 11: eth_tx_clk (GPIOH_9) - register 6 bit 12: eth_txd2 (GPIOH_8) - register 6 bit 13: eth_txd3 (GPIOH_7) - register 7 bit 20: eth_txd0_0 (GPIOH_6) - register 7 bit 21: eth_txd1_0 (GPIOH_5) - register 7 bit 22: eth_rxd3 (DIF_2_P) - register 7 bit 23: eth_rxd2 (DIF_2_N)
Drop the eth_txd0_1 and eth_txd1_1 groups from eth_rgmii_pins to fix the Ethernet transmit performance on Odroid-C1. Also add the eth_rxd2 and eth_rxd3 groups so we don't rely on the bootloader to set them up.
iperf3 statistics before this change: - transmitting from Odroid-C1: 741 Mbits/sec (0 retries) - receiving on Odroid-C1: 199 Mbits/sec (1713 retries)
iperf3 statistics after this change: - transmitting from Odroid-C1: 667 Mbits/sec (0 retries) - receiving on Odroid-C1: 750 Mbits/sec (0 retries)
Fixes: b96446541d8390 ("ARM: dts: meson8b: extend ethernet controller description") Signed-off-by: Martin Blumenstingl martin.blumenstingl@googlemail.com Cc: Emiliano Ingrassia ingrassia@epigenesys.com Cc: Linus Lüssing linus.luessing@c0d3.blue Tested-by: Emiliano Ingrassia ingrassia@epigenesys.com Reviewed-by: Emiliano Ingrassia ingrassia@epigenesys.com Signed-off-by: Kevin Hilman khilman@baylibre.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/arm/boot/dts/meson8b.dtsi | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/arm/boot/dts/meson8b.dtsi b/arch/arm/boot/dts/meson8b.dtsi index 08f7f6be7254..5b3e5c50c72f 100644 --- a/arch/arm/boot/dts/meson8b.dtsi +++ b/arch/arm/boot/dts/meson8b.dtsi @@ -207,9 +207,7 @@ groups = "eth_tx_clk", "eth_tx_en", "eth_txd1_0", - "eth_txd1_1", "eth_txd0_0", - "eth_txd0_1", "eth_rx_clk", "eth_rx_dv", "eth_rxd1", @@ -218,7 +216,9 @@ "eth_mdc", "eth_ref_clk", "eth_txd2", - "eth_txd3"; + "eth_txd3", + "eth_rxd3", + "eth_rxd2"; function = "ethernet"; }; };