Subject: [PATCH] ARM: dts: ls1021a-tsn: Use interrupts for the SGMII PHYs

From: Vladimir Oltean <[email-masked]>
Date: Sat, 9 Nov 2019 12:56:42 +0200

On the LS1021A-TSN board, the 2 Atheros AR8031 PHYs for eth0 and eth1
have interrupt lines connected to the shared IRQ2_B LS1021A pin.

The interrupts are active low, but the GICv2 controller does not support
active-low and falling-edge interrupts, so the only mode it can be
configured in is rising-edge.

The interrupt number was obtained by subtracting 32 from the listed
interrupt ID from LS1021ARM.pdf Table 5-1. Interrupt assignments.

Switching to interrupts offloads the PHY library from the task of
polling the MDIO status and AN registers (1, 4, 5) every second.

Unfortunately, the BCM5464R quad PHY connected to the switch does not
appear to have an interrupt line routed to the SoC.

Signed-off-by: Vladimir Oltean <[email-masked]>
---
 arch/arm/boot/dts/ls1021a-tsn.dts | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/arm/boot/dts/ls1021a-tsn.dts b/arch/arm/boot/dts/ls1021a-tsn.dts
index 5b7689094b70..4532b2bd3fd1 100644
--- a/arch/arm/boot/dts/ls1021a-tsn.dts
+++ b/arch/arm/boot/dts/ls1021a-tsn.dts
@@ -203,11 +203,15 @@
 	/* AR8031 */
 	sgmii_phy1: ethernet-phy@1 {
 		reg = <0x1>;
+		/* SGMII1_PHY_INT_B: connected to IRQ2, active low */
+		interrupts = <GIC_SPI 165 IRQ_TYPE_EDGE_RISING>;
 	};
 
 	/* AR8031 */
 	sgmii_phy2: ethernet-phy@2 {
 		reg = <0x2>;
+		/* SGMII2_PHY_INT_B: connected to IRQ2, active low */
+		interrupts = <GIC_SPI 165 IRQ_TYPE_EDGE_RISING>;
 	};
 
 	/* BCM5464 quad PHY */
-- 
2.17.1

_______________________________________________
linux-arm-kernel mailing list
[email-masked]
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel