From 4a63c1c1ed78c6ae1cc4528314216e0d7945368a Mon Sep 17 00:00:00 2001
From: Emmanuel Vadot <manu@FreeBSD.org>
Date: Sat, 10 Oct 2020 07:18:51 +0000
Subject: [PATCH] Brand our DTS with the Linux version it was imported from

DTS must be synced with the kernel, add a freebsd,dts-version string in
the root node of each DTS that we compile so we can later in the kernel
check that it contain a correct value.

Reviewed by:	imp, mmel
Differential Revision:	https://reviews.freebsd.org/D26724
---
 sys/conf/Makefile.arm          | 3 +++
 sys/dts/freebsd-compatible.dts | 3 +++
 sys/gnu/dts/Makefile           | 3 +++
 sys/tools/fdt/make_dtb.sh      | 4 +++-
 4 files changed, 12 insertions(+), 1 deletion(-)
 create mode 100644 sys/dts/freebsd-compatible.dts
 create mode 100644 sys/gnu/dts/Makefile

diff --git a/sys/conf/Makefile.arm b/sys/conf/Makefile.arm
index 1d0ab347827b..cc827e88c44f 100644
--- a/sys/conf/Makefile.arm
+++ b/sys/conf/Makefile.arm
@@ -32,6 +32,9 @@ S=	../../..
 
 INCLUDES+= -I$S/contrib/libfdt -I$S/gnu/dts/include 
 
+LINUX_DTS_VERSION!=	       make -C $S/gnu/dts/ -V LINUX_DTS_VERSION
+CFLAGS += -DLINUX_DTS_VERSION=\"${LINUX_DTS_VERSION}\"
+
 .if !defined(DEBUG) && !defined(PROFLEVEL)
 STRIP_FLAGS = -S
 .endif
diff --git a/sys/dts/freebsd-compatible.dts b/sys/dts/freebsd-compatible.dts
new file mode 100644
index 000000000000..d977cb2b30c8
--- /dev/null
+++ b/sys/dts/freebsd-compatible.dts
@@ -0,0 +1,3 @@
+/ {
+	freebsd,dts-version = LINUX_DTS_VERSION;
+};
diff --git a/sys/gnu/dts/Makefile b/sys/gnu/dts/Makefile
new file mode 100644
index 000000000000..140e5c1bc464
--- /dev/null
+++ b/sys/gnu/dts/Makefile
@@ -0,0 +1,3 @@
+# $FreeBSD$
+
+LINUX_DTS_VERSION=5.8
diff --git a/sys/tools/fdt/make_dtb.sh b/sys/tools/fdt/make_dtb.sh
index b33dc39609cb..5c5968711661 100755
--- a/sys/tools/fdt/make_dtb.sh
+++ b/sys/tools/fdt/make_dtb.sh
@@ -20,9 +20,11 @@ fi
 : "${ECHO:=echo}"
 : "${CPP:=cpp}"
 
+LINUX_DTS_VERSION=$(make -C $S/gnu/dts -V LINUX_DTS_VERSION)
+
 for d in ${dts}; do
     dtb="${dtb_path}/$(basename "$d" .dts).dtb"
     ${ECHO} "converting $d -> $dtb"
-    ${CPP} -P -x assembler-with-cpp -I "$S/gnu/dts/include" -I "$S/dts/${MACHINE}" -I "$S/gnu/dts/${MACHINE}" -I "$S/gnu/dts/" -include "$d" /dev/null |
+    ${CPP} -DLINUX_DTS_VERSION=\"${LINUX_DTS_VERSION}\" -P -x assembler-with-cpp -I "$S/gnu/dts/include" -I "$S/dts/${MACHINE}" -I "$S/gnu/dts/${MACHINE}" -I "$S/gnu/dts/" -include "$d" -include "$S/dts/freebsd-compatible.dts" /dev/null |
 	${DTC} -@ -O dtb -o "$dtb" -b 0 -p 1024 -i "$S/dts/${MACHINE}" -i "$S/gnu/dts/${MACHINE}" -i "$S/gnu/dts/"
 done