ar71xx: Enable mtdsplit support for RB SPI NOR devices

This patch enables mtdsplit for the MikroTik subtarget.
It converts mach-rbspi.c to use a single "firmware" partition.
Finally, it converts the SPI NOR profile to metadata images:
the original combined-image format is gone, the images are now
"standard" sysupgrade images with metadata appended.

Note: kernel2minor apparently pads the kernel container to erase-block
boundary, but this is undocumented behaviour, so we do not rely on it
and call pad-to anyway.

Note: in platform.sh, the boards are tested last in platform_check_image()
as this should eventually become the "*)" default case when more devices
switch to metadata images.

Signed-off-by: Thibaut VARENE <hacks@slashdirt.org>

target/linux/ar71xx/base-files/lib/upgrade/platform.sh

@@ -344,11 +344,6 @@ platform_check_image() {
 	ls-sr71|\
 	pb42|\
 	pb44|\
-	rb-750-r2|\
-	rb-750up-r2|\
-	rb-941-2nd|\
-	rb-951ui-2nd|\
-	rb-mapl-2nd|\
 	routerstation-pro|\
 	routerstation|\
 	wp543|\
@@ -637,6 +632,14 @@ platform_check_image() {
 
 		return 0;
 		;;
+	# these boards use metadata images
+	rb-750-r2|\
+	rb-750up-r2|\
+	rb-941-2nd|\
+	rb-951ui-2nd|\
+	rb-mapl-2nd)
+		return 0
+		;;
 	esac
 
 	echo "Sysupgrade is not yet supported on $board."
@@ -707,14 +710,6 @@ platform_do_upgrade() {
 	local board=$(ar71xx_board_name)
 
 	case "$board" in
-	rb-750-r2|\
-	rb-750up-r2|\
-	rb-941-2nd|\
-	rb-951ui-2nd|\
-	rb-mapl-2nd)
-		PLATFORM_DO_UPGRADE_COMBINED_SEPARATE_MTD=1
-		platform_do_upgrade_combined "$ARGV"
-		;;
 	all0258n)
 		platform_do_upgrade_allnet "0x9f050000" "$ARGV"
 		;;

target/linux/ar71xx/config-4.4

@@ -380,6 +380,7 @@ CONFIG_MTD_SPLIT_LZMA_FW=y
 CONFIG_MTD_SPLIT_SEAMA_FW=y
 CONFIG_MTD_SPLIT_UIMAGE_FW=y
 CONFIG_MTD_SPLIT_WRGG_FW=y
+CONFIG_MTD_SPLIT_MINOR_FW=y
 CONFIG_MTD_TPLINK_PARTS=y
 CONFIG_MYLOADER=y
 CONFIG_NEED_DMA_MAP_STATE=y

target/linux/ar71xx/files/arch/mips/ath79/mach-rbspi.c

@@ -60,7 +60,6 @@
 #define RB_ROUTERBOOT_OFFSET    0x0000
 #define RB_BIOS_SIZE            0x1000
 #define RB_SOFT_CFG_SIZE        0x1000
-#define RB_KERNEL_SIZE          (2 * 1024 * 1024)	/* 2MB kernel */
 
 /* Flash partitions indexes */
 enum {
@@ -69,8 +68,7 @@ enum {
 	RBSPI_PART_BIOS,
 	RBSPI_PART_RBOOT2,
 	RBSPI_PART_SCONF,
-	RBSPI_PART_KERN,
-	RBSPI_PART_ROOT,
+	RBSPI_PART_FIRMW,
 	RBSPI_PARTS
 };
 
@@ -79,8 +77,6 @@ static struct mtd_partition rbspi_spi_partitions[RBSPI_PARTS];
 /*
  * Setup the SPI flash partition table based on initial parsing.
  * The kernel can be at any aligned position and have any size.
- * The size of the kernel partition is the desired RB_KERNEL_SIZE
- * minus the size of the preceding partitions (128KB).
  */
 static void __init rbspi_init_partitions(const struct rb_info *info)
 {
@@ -114,16 +110,10 @@ static void __init rbspi_init_partitions(const struct rb_info *info)
 	parts[RBSPI_PART_SCONF].offset = info->soft_cfg_offs;
 	parts[RBSPI_PART_SCONF].size = RB_SOFT_CFG_SIZE;
 
-	parts[RBSPI_PART_KERN].name = "kernel";
-	parts[RBSPI_PART_KERN].offset = parts[RBSPI_PART_SCONF].offset
+	parts[RBSPI_PART_FIRMW].name = "firmware";
+	parts[RBSPI_PART_FIRMW].offset = parts[RBSPI_PART_SCONF].offset
 					+ parts[RBSPI_PART_SCONF].size;
-	parts[RBSPI_PART_KERN].size = RB_KERNEL_SIZE
-					- parts[RBSPI_PART_KERN].offset;
-
-	parts[RBSPI_PART_ROOT].name = "rootfs";
-	parts[RBSPI_PART_ROOT].offset = parts[RBSPI_PART_KERN].offset
-					+ parts[RBSPI_PART_KERN].size;
-	parts[RBSPI_PART_ROOT].size = MTDPART_SIZ_FULL;
+	parts[RBSPI_PART_FIRMW].size = MTDPART_SIZ_FULL;
 }
 
 static struct flash_platform_data rbspi_spi_flash_data = {

target/linux/ar71xx/image/mikrotik.mk

@@ -27,14 +27,13 @@ TARGET_DEVICES += nand-64m nand-large
 define Device/rb-nor-flash-16M
   DEVICE_TITLE := MikroTik RouterBoard with 16 MB SPI NOR flash
   DEVICE_PACKAGES := rbcfg
-  BLOCKSIZE := 64k
   IMAGE_SIZE := 16000k
   LOADER_TYPE := elf
   KERNEL_INSTALL := 1
-  KERNEL := kernel-bin | lzma | loader-kernel | kernel2minor -s 1024 -e
-  KERNEL_INITRAMFS := kernel-bin | lzma | loader-kernel
-  IMAGES := sysupgrade.bin
-  IMAGE/sysupgrade.bin = append-rootfs | pad-rootfs | combined-image | check-size $$$$(IMAGE_SIZE)
+  KERNEL := kernel-bin | lzma | loader-kernel
+  SUPPORTED_DEVICES := rb-750-r2 rb-750up-r2 rb-941-2nd rb-951ui-2nd rb-mapl-2nd
+  IMAGE/sysupgrade.bin = append-kernel | kernel2minor -s 1024 -e | pad-to $$$$(BLOCKSIZE) | \
+	append-rootfs | pad-rootfs | append-metadata | check-size $$$$(IMAGE_SIZE)
 endef
 
 TARGET_DEVICES += rb-nor-flash-16M