From f94e5560accbead99c48ab0dfbfa40e2147b2bd6 Mon Sep 17 00:00:00 2001
From: bbracker <bbracker@hmc.edu>
Date: Tue, 8 Feb 2022 11:11:44 +0000
Subject: [PATCH] add trimmed-down virt devicetree to repo for QEMU

---
 .gitignore                        |  2 +
 linux/devicetree/debug/dumpdts.sh |  6 +++
 linux/devicetree/virt-trimmed.dts | 75 +++++++++++++++++++++++++++++++
 3 files changed, 83 insertions(+)
 create mode 100755 linux/devicetree/debug/dumpdts.sh
 create mode 100644 linux/devicetree/virt-trimmed.dts

diff --git a/.gitignore b/.gitignore
index fca93ebb..94462b42 100644
--- a/.gitignore
+++ b/.gitignore
@@ -53,3 +53,5 @@ examples/asm/example/example
 examples/C/sum/sum
 examples/C/fir/fir
 synthDC/hdl/*.sv
+linux/devicetree/debug/*
+!linux/devicetree/debug/dumpdts.sh
diff --git a/linux/devicetree/debug/dumpdts.sh b/linux/devicetree/debug/dumpdts.sh
new file mode 100755
index 00000000..70057a78
--- /dev/null
+++ b/linux/devicetree/debug/dumpdts.sh
@@ -0,0 +1,6 @@
+#!/bin/bash
+machine=virt
+
+qemu-system-riscv64 -M $machine,dumpdtb=$machine.dtb -bios $RISCV/buildroot/output/images/fw_jump.elf
+
+dtc -I dtb -O dts $machine.dtb > $machine.dts
diff --git a/linux/devicetree/virt-trimmed.dts b/linux/devicetree/virt-trimmed.dts
new file mode 100644
index 00000000..b517c3de
--- /dev/null
+++ b/linux/devicetree/virt-trimmed.dts
@@ -0,0 +1,75 @@
+/dts-v1/;
+
+/ {
+	#address-cells = <0x02>;
+	#size-cells = <0x02>;
+	compatible = "riscv-virtio-trimmed";
+	model = "riscv-virtio-trimmed,qemu";
+
+	chosen {
+		linux,initrd-end = <0x85c43a00>;
+		linux,initrd-start = <0x84200000>;
+		bootargs = "root=/dev/vda ro";
+		stdout-path = "/soc/uart@10000000";
+	};
+
+	memory@80000000 {
+		device_type = "memory";
+		reg = <0x00 0x80000000 0x00 0x8000000>;
+	};
+
+	cpus {
+		#address-cells = <0x01>;
+		#size-cells = <0x00>;
+		timebase-frequency = <0x989680>;
+
+		cpu@0 {
+			phandle = <0x01>;
+			device_type = "cpu";
+			reg = <0x00>;
+			status = "okay";
+			compatible = "riscv";
+			riscv,isa = "rv64imafdcsu";
+			mmu-type = "riscv,sv48";
+
+			interrupt-controller {
+				#interrupt-cells = <0x01>;
+				interrupt-controller;
+				compatible = "riscv,cpu-intc";
+				phandle = <0x02>;
+			};
+		};
+	};
+
+	soc {
+		#address-cells = <0x02>;
+		#size-cells = <0x02>;
+		compatible = "simple-bus";
+		ranges;
+
+		uart@10000000 {
+			interrupts = <0x0a>;
+			interrupt-parent = <0x03>;
+			clock-frequency = <0x384000>;
+			reg = <0x00 0x10000000 0x00 0x100>;
+			compatible = "ns16550a";
+		};
+
+		plic@c000000 {
+			phandle = <0x03>;
+			riscv,ndev = <0x35>;
+			reg = <0x00 0xc000000 0x00 0x210000>;
+			interrupts-extended = <0x02 0x0b 0x02 0x09>;
+			interrupt-controller;
+			compatible = "sifive,plic-1.0.0\0riscv,plic0";
+			#interrupt-cells = <0x01>;
+			#address-cells = <0x00>;
+		};
+
+		clint@2000000 {
+			interrupts-extended = <0x02 0x03 0x02 0x07>;
+			reg = <0x00 0x2000000 0x00 0x10000>;
+			compatible = "sifive,clint0\0riscv,clint0";
+		};
+	};
+};