From e13c663bfc75a628ba25afdf3f3b4a40a2c0250e Mon Sep 17 00:00:00 2001
From: P33M <p33m@github.com>
Date: Wed, 1 May 2019 15:00:05 +0100
Subject: [PATCH] dts: Increase default coherent pool size

dwc_otg allocates DMA-coherent buffers in atomic context for misaligned
transfer buffers. The pool that these allocations come from is set up
at boot-time but can be overridden by a commandline parameter -
increase this for now to prevent failures seen on 4.19 with multiple
USB Ethernet devices.

see: https://github.com/raspberrypi/linux/issues/2924
---
 arch/arm/boot/dts/bcm270x.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/arm/boot/dts/bcm270x.dtsi
+++ b/arch/arm/boot/dts/bcm270x.dtsi
@@ -3,7 +3,7 @@
 
 / {
 	chosen {
-		bootargs = "";
+		bootargs = "coherent_pool=1M";
 		/delete-property/ stdout-path;
 	};