From 5c8e55934b002b453eeb6ad8d1e59c0d7e69b69f Mon Sep 17 00:00:00 2001
From: Alex Tunstall <alex@tunstall.xyz>
Date: Thu, 25 Apr 2024 03:54:54 +0100
Subject: [PATCH] Fix only 4GiB of memory being available

This might have been caused by the switch to
generic-extlinux-compatible, but u-boot seems to be honouring the FDT
option.
---
 modules/boot/8gb-patch.dts | 11 +++++++++++
 modules/boot/default.nix   |  4 ++++
 2 files changed, 15 insertions(+)
 create mode 100644 modules/boot/8gb-patch.dts

diff --git a/modules/boot/8gb-patch.dts b/modules/boot/8gb-patch.dts
new file mode 100644
index 0000000..342dcba
--- /dev/null
+++ b/modules/boot/8gb-patch.dts
@@ -0,0 +1,11 @@
+/dts-v1/;
+/plugin/;
+/ {
+	compatible = "starfive,jh7110";
+	fragment@0 {
+		target-path = "/memory@40000000";
+		__overlay__ {
+			reg = <0x0 0x40000000 0x2 0x0>;
+		};
+	};
+};
diff --git a/modules/boot/default.nix b/modules/boot/default.nix
index b384e22..53f5359 100644
--- a/modules/boot/default.nix
+++ b/modules/boot/default.nix
@@ -50,6 +50,10 @@
   hardware.deviceTree.name = "starfive/jh7110-starfive-visionfive-2-v1.3b.dtb";
 
   hardware.deviceTree.overlays = [
+    {
+      name = "8gb-patch";
+      dtsFile = ./8gb-patch.dts;
+    }
     # https://github.com/starfive-tech/linux/pull/99
     {
       name = "qspi-patch";