gemini: Generate padded kernel+rootfs images for DIR-685

We currently generate a kernel that boots from the harddrive
in the DIR-685. That's not how we usually do things, so
let's augment it to boot from flash and mount the rootfs
using squashfs and JFFS2 like everyone else.

Partition splitting only work when the partitions are
inside of a "partitions" node which is why we have a patch
like this (submitted upstream).

Another patch drops the rootfs arguments and renames the
firmware partition while adding the compatible "wrg"
to it so the WRGG parser will kick in.

Factory image was tested by bravely reflashing the DIR-685
from stock firmware using the web UI and the serial console
boot loader.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

2 files changed, 150 insertions, 0 deletions

diff --git a/target/linux/gemini/patches-4.19/0019-ARM-dts-gemini-Indent-DIR-685-partition-table.patch b/target/linux/gemini/patches-4.19/0019-ARM-dts-gemini-Indent-DIR-685-partition-table.patch
new file mode 100644
index 0000000000..b121ca174e
--- /dev/null
+++ b/target/linux/gemini/patches-4.19/0019-ARM-dts-gemini-Indent-DIR-685-partition-table.patch
@@ -0,0 +1,110 @@
+From 4a228ecf553e879bae384e634bb6413438e81a0e Mon Sep 17 00:00:00 2001
+From: Linus Walleij <linus.walleij@linaro.org>
+Date: Mon, 11 Mar 2019 15:43:05 +0100
+Subject: [PATCH 1/2] ARM: dts: gemini: Indent DIR-685 partition table
+
+It is discouraged to have OF partitions as subnodes directly
+under the device, create a "partitions" subnode and put the
+partitions inside it.
+
+Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
+---
+ arch/arm/boot/dts/gemini-dlink-dir-685.dts | 82 ++++++++++++----------
+ 1 file changed, 44 insertions(+), 38 deletions(-)
+
+diff --git a/arch/arm/boot/dts/gemini-dlink-dir-685.dts b/arch/arm/boot/dts/gemini-dlink-dir-685.dts
+index 9b2824816ddc..50ff65d95f26 100644
+--- a/arch/arm/boot/dts/gemini-dlink-dir-685.dts
++++ b/arch/arm/boot/dts/gemini-dlink-dir-685.dts
+@@ -267,44 +267,50 @@
+ 			/* 32MB of flash */
+ 			reg = <0x30000000 0x02000000>;
+ 
+-			/*
+-			 * This "RedBoot" is the Storlink derivative.
+-			 */
+-			partition@0 {
+-				label = "RedBoot";
+-				reg = <0x00000000 0x00040000>;
+-				read-only;
+-			};
+-			/*
+-			 * This firmware image contains the kernel catenated
+-			 * with the squashfs root filesystem. For some reason
+-			 * this is called "upgrade" on the vendor system.
+-			 */
+-			partition@40000 {
+-				label = "upgrade";
+-				reg = <0x00040000 0x01f40000>;
+-				read-only;
+-			};
+-			/* RGDB, Residental Gateway Database? */
+-			partition@1f80000 {
+-				label = "rgdb";
+-				reg = <0x01f80000 0x00040000>;
+-				read-only;
+-			};
+-			/*
+-			 * This partition contains MAC addresses for WAN,
+-			 * WLAN and LAN, and the country code (for wireless
+-			 * I guess).
+-			 */
+-			partition@1fc0000 {
+-				label = "nvram";
+-				reg = <0x01fc0000 0x00020000>;
+-				read-only;
+-			};
+-			partition@1fe0000 {
+-				label = "LangPack";
+-				reg = <0x01fe0000 0x00020000>;
+-				read-only;
++			partitions {
++				compatible = "fixed-partitions";
++				#address-cells = <1>;
++				#size-cells = <1>;
++
++				/*
++				 * This "RedBoot" is the Storlink derivative.
++				 */
++				partition@0 {
++					label = "RedBoot";
++					reg = <0x00000000 0x00040000>;
++					read-only;
++				};
++				/*
++				 * This firmware image contains the kernel catenated
++				 * with the squashfs root filesystem. For some reason
++				 * this is called "upgrade" on the vendor system.
++				 */
++				partition@40000 {
++					label = "upgrade";
++					reg = <0x00040000 0x01f40000>;
++					read-only;
++				};
++				/* RGDB, Residental Gateway Database? */
++				partition@1f80000 {
++					label = "rgdb";
++					reg = <0x01f80000 0x00040000>;
++					read-only;
++				};
++				/*
++				 * This partition contains MAC addresses for WAN,
++				 * WLAN and LAN, and the country code (for wireless
++				 * I guess).
++				 */
++				partition@1fc0000 {
++					label = "nvram";
++					reg = <0x01fc0000 0x00020000>;
++					read-only;
++				};
++				partition@1fe0000 {
++					label = "LangPack";
++					reg = <0x01fe0000 0x00020000>;
++					read-only;
++				};
+ 			};
+ 		};
+ 
+-- 
+2.20.1
+
diff --git a/target/linux/gemini/patches-4.19/0020-ARM-dts-Augment-DIR-685-partition-table-for-OpenWrt.patch b/target/linux/gemini/patches-4.19/0020-ARM-dts-Augment-DIR-685-partition-table-for-OpenWrt.patch
new file mode 100644
index 0000000000..bf044e0c69
--- /dev/null
+++ b/target/linux/gemini/patches-4.19/0020-ARM-dts-Augment-DIR-685-partition-table-for-OpenWrt.patch
@@ -0,0 +1,40 @@
+From 854934b0ce8e758ce581f5ddbc30e618ab46fbdb Mon Sep 17 00:00:00 2001
+From: Linus Walleij <linus.walleij@linaro.org>
+Date: Mon, 11 Mar 2019 15:44:29 +0100
+Subject: [PATCH 2/2] ARM: dts: Augment DIR-685 partition table for OpenWrt
+
+Rename the firmware partition so that the firmware MTD
+splitter will do its job, drop the rootfs arguments as
+the MTD splitter will set this up automatically.
+
+Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
+---
+ arch/arm/boot/dts/gemini-dlink-dir-685.dts | 5 +++--
+ 1 file changed, 3 insertions(+), 2 deletions(-)
+
+diff --git a/arch/arm/boot/dts/gemini-dlink-dir-685.dts b/arch/arm/boot/dts/gemini-dlink-dir-685.dts
+index 50ff65d95f26..7db30cc9d189 100644
+--- a/arch/arm/boot/dts/gemini-dlink-dir-685.dts
++++ b/arch/arm/boot/dts/gemini-dlink-dir-685.dts
+@@ -20,7 +20,7 @@
+ 	};
+ 
+ 	chosen {
+-		bootargs = "console=ttyS0,19200n8 root=/dev/sda1 rw rootwait consoleblank=300";
++		bootargs = "console=ttyS0,19200n8 consoleblank=300";
+ 		stdout-path = "uart0:19200n8";
+ 	};
+ 
+@@ -286,7 +286,8 @@
+ 				 * this is called "upgrade" on the vendor system.
+ 				 */
+ 				partition@40000 {
+-					label = "upgrade";
++					compatible = "wrg";
++					label = "firmware";
+ 					reg = <0x00040000 0x01f40000>;
+ 					read-only;
+ 				};
+-- 
+2.20.1
+