ath79: modify mtd partitions for Buffalo BHR-4GRV2

This commit modifies mtd partitions define for Buffalo BHR-4GRV2 and
move it to generic subtarget.

In Buffalo BHR-4GRV2, "kernel" partition is located behined "rootfs"
partition in the stock firmware. This causes the size of the kernel
to be limited by the fixed value.

0x50000                       0xe80000        0xff0000
  +-------------------------------+--------------+
  |            rootfs             |    kernel    |
  |           (14528k)            |    (1472k)   |
  +-------------------------------+--------------+

After ar71xx was updated to Kernel 4.14, the kernel size of BHR-4GRV2
exceeded the limit, and it breaks builds on official buildbot.
Since this issue was also confirmed in ath79, I modified the mtd
partitions to get rid of that limitation.

0x50000                                       0xff0000
  +----------------------------------------------+
  |                   firmware                   |
  |                   (16000k)                   |
  +----------------------------------------------+

However, this commit breaks compatibility with ar71xx firmware, so I
dropped "SUPPORTED_DEVICES += bhr-4grv2".

This commit requires new flash instruction instead of the old one.

Flash instruction using initramfs image:

1. Connect the computer to the LAN port of BHR-4GRV2
2. Set the IP address of the computer to 192.168.12.10
3. Rename the OpenWrt initramfs image to
"bhr4grv2-uImage-initramfs-gzip.bin" and place it into the TFTP
directory
4. Start the tftp server on the computer
5. While holding down the "ECO" button, connect power cable to
BHR-4GRV2 and turn on it
6. Flashing (orange) diag LED and release the finger from the button,
BHR-4GRV2 downloads the intiramfs image from TFTP server and boot
with it
7. On the initramfs image, create "/etc/fw_env.config" file with
following contents
  /dev/mtd1 0x0 0x10000 0x10000
8. Execute following commands to add environment variables for
u-boot
  fw_setenv ipaddr 192.168.12.1
  fw_setenv serverip 192.168.12.10
  fw_setenv ethaddr 00:aa:bb:cc:dd:ee
  fw_setenv bootcmd "bootm 0x9f050000 || bootm 0x9fe80000"
9. Perform sysupgrade with squashfs-sysupgrade image
10. Wait ~150 seconds to complete flashing

And this commit includes small fix; BHR-4GRV2 has QCA9557 as a SoC,
not QCA9558.

Signed-off-by: INAGAKI Hiroshi <musashino.open@gmail.com>

include/image-commands.mk

@@ -62,14 +62,6 @@ define Build/zyxel-ras-image
 		&& mv $@.new $@
 endef
 
-define Build/mkbuffaloimg
-	$(STAGING_DIR_HOST)/bin/mkbuffaloimg -B $(BOARDNAME) \
-		-R $$(($(subst k, * 1024,$(ROOTFS_SIZE)))) \
-		-K $$(($(subst k, * 1024,$(KERNEL_SIZE)))) \
-		-i $@ -o $@.new
-	mv $@.new $@
-endef
-
 define Build/netgear-chk
 	$(STAGING_DIR_HOST)/bin/mkchkimg \
 		-o $@.new \

target/linux/ar71xx/image/tiny.mk

@@ -1,3 +1,12 @@
+define Build/mkbuffaloimg
+	$(STAGING_DIR_HOST)/bin/mkbuffaloimg -B $(BOARDNAME) \
+		-R $$(($(subst k, * 1024,$(ROOTFS_SIZE)))) \
+		-K $$(($(subst k, * 1024,$(KERNEL_SIZE)))) \
+		-i $@ -o $@.new
+	mv $@.new $@
+endef
+
+
 define Device/bhr-4grv2
   DEVICE_TITLE := Buffalo BHR-4GRV2
   BOARDNAME := BHR-4GRV2

target/linux/ath79/base-files/lib/upgrade/platform.sh

@@ -22,10 +22,6 @@ platform_do_upgrade() {
 	local board=$(board_name)
 
 	case "$board" in
-	buffalo,bhr-4grv2)
-		PART_NAME="rootfs:kernel"
-		default_do_upgrade "$ARGV"
-		;;
 	ubnt,routerstation|\
 	ubnt,routerstation-pro)
 		routerstation_do_upgrade "$ARGV"

target/linux/ath79/dts/qca9557_buffalo_bhr-4grv2.dts

@@ -93,17 +93,12 @@
 			partition@40000 {
 				label = "u-boot-env";
 				reg = <0x040000 0x010000>;
-				read-only;
 			};
 
 			partition@50000 {
-				label = "rootfs";
+				compatible = "denx,uimage";
-				reg = <0x050000 0xe30000>;
+				label = "firmware";
-			};
+				reg = <0x050000 0xfa0000>;
-
-			partition@e80000 {
-				label = "kernel";
-				reg = <0xe80000 0x170000>;
 			};
 
 			art: partition@ff0000 {

target/linux/ath79/image/generic.mk

@@ -82,6 +82,13 @@ define Device/buffalo_bhr-4grv
 endef
 TARGET_DEVICES += buffalo_bhr-4grv
 
+define Device/buffalo_bhr-4grv2
+  ATH_SOC := qca9557
+  DEVICE_TITLE := Buffalo BHR-4GRV2
+  IMAGE_SIZE := 16000k
+endef
+TARGET_DEVICES += buffalo_bhr-4grv2
+
 define Device/buffalo_wzr-hp-ag300h
   ATH_SOC := ar7161
   DEVICE_TITLE := Buffalo WZR-HP-AG300H

target/linux/ath79/image/tiny.mk

@@ -1,24 +1,5 @@
 include ./common-buffalo.mk
 
-DEVICE_VARS += ROOTFS_SIZE
-
-define Device/buffalo_bhr-4grv2
-  ATH_SOC := qca9558
-  DEVICE_TITLE := Buffalo BHR-4GRV2
-  BOARDNAME := BHR-4GRV2
-  ROOTFS_SIZE := 14528k
-  KERNEL_SIZE := 1472k
-  IMAGE_SIZE := 16000k
-  IMAGES += factory.bin
-  IMAGE/sysupgrade.bin := \
-    append-rootfs | pad-rootfs | pad-to $$$$(ROOTFS_SIZE) | \
-    append-kernel | append-metadata | check-size $$$$(IMAGE_SIZE)
-  IMAGE/factory.bin := append-kernel | \
-    pad-to $$$$(KERNEL_SIZE) | append-rootfs | pad-rootfs | mkbuffaloimg
-  SUPPORTED_DEVICES += bhr-4grv2
-endef
-TARGET_DEVICES += buffalo_bhr-4grv2
-
 define Device/buffalo_whr-g301n
   ATH_SOC := ar7240
   DEVICE_TITLE := Buffalo WHR-G301N