Add partial 6.1 support for ips40xx

6.1/target/linux/ipq40xx/patches-6.1/301-arm-compressed-add-appended-DTB-section.patch

@@ -0,0 +1,48 @@
+From 0843a61d6913bdac8889eb048ed89f7903059787 Mon Sep 17 00:00:00 2001
+From: Robert Marko <robimarko@gmail.com>
+Date: Fri, 30 Oct 2020 13:36:31 +0100
+Subject: [PATCH] arm: compressed: add appended DTB section
+
+This adds a appended_dtb section to the ARM decompressor
+linker script.
+
+This allows using the existing ARM zImage appended DTB support for
+appending a DTB to the raw ELF kernel.
+
+Its size is set to 1MB max to match the zImage appended DTB size limit.
+
+To use it to pass the DTB to the kernel, objcopy is used:
+
+objcopy --set-section-flags=.appended_dtb=alloc,contents \
+	--update-section=.appended_dtb=<target>.dtb vmlinux
+
+This is based off the following patch:
+https://github.com/openwrt/openwrt/commit/c063e27e02a9dcac0e7f5877fb154e58fa3e1a69
+
+Signed-off-by: Robert Marko <robimarko@gmail.com>
+---
+ arch/arm/boot/compressed/vmlinux.lds.S | 9 ++++++++-
+ 1 file changed, 8 insertions(+), 1 deletion(-)
+
+--- a/arch/arm/boot/compressed/vmlinux.lds.S
++++ b/arch/arm/boot/compressed/vmlinux.lds.S
+@@ -103,6 +103,13 @@ SECTIONS
+ 
+   _edata = .;
+ 
++  .appended_dtb : {
++    /* leave space for appended DTB */
++    . += 0x100000;
++  }
++
++  _edata_dtb = .;
++
+   /*
+    * The image_end section appears after any additional loadable sections
+    * that the linker may decide to insert in the binary image.  Having
+@@ -140,4 +147,4 @@ SECTIONS
+ 
+   ARM_ASSERTS
+ }
+-ASSERT(_edata_real == _edata, "error: zImage file size is incorrect");
++ASSERT(_edata_real == _edata_dtb, "error: zImage file size is incorrect");