Hi,
I recently got interested in OpenWrt and I'm trying to port a new device to be supported. It is a long way up for me of reading OpenWrt developer documentation and trying.
I have an pre-production sample of D-Link X530 with heavilly modified OpenWrt version.
This is the same main platform, as M30 (filogic, MT7981b).
By using serial console and initramfs firmware for M30 (it boots), I was able to get image of kernel partition and with some ChatGPT help 
extract the DTS file from it.
Then, I followed OpenWrt documentation to add it to the OpenWrt source tree in places when I saw M30, adjusting it a bit for flash layout and so on.:
Diff file
diff --git a/package/boot/uboot-envtools/files/mediatek_filogic b/package/boot/uboot-envtools/files/mediatek_filogic
index 1bf63d3061..fe2055b62b 100644
--- a/package/boot/uboot-envtools/files/mediatek_filogic
+++ b/package/boot/uboot-envtools/files/mediatek_filogic
@@ -104,6 +104,9 @@ dlink,aquila-pro-ai-m30-a1|\
dlink,aquila-pro-ai-m60-a1)
ubootenv_add_uci_config "/dev/mtd1" "0x0" "0x40000" "0x40000"
;;
+dlink,x530-a1)
+ ubootenv_add_uci_config "/dev/mtd1" "0x0" "0x80000" "0x80000"
+ ;;
gatonetworks,gdsp)
ubootenv_add_uci_config "/dev/mtd1" "0x0" "0x10000" "0x10000"
;;
diff --git a/target/linux/mediatek/filogic/base-files/etc/board.d/02_network b/target/linux/mediatek/filogic/base-files/etc/board.d/02_network
index f9bf2b1faf..57fccbebaa 100644
--- a/target/linux/mediatek/filogic/base-files/etc/board.d/02_network
+++ b/target/linux/mediatek/filogic/base-files/etc/board.d/02_network
@@ -110,6 +110,9 @@ mediatek_setup_interfaces()
dlink,aquila-pro-ai-m60-a1)
ucidef_set_interfaces_lan_wan "lan1 lan2 lan3 lan4" internet
;;
+ dlink,x530-a1)
+ ucidef_set_interfaces_lan_wan lan internet
+ ;;
keenetic,kn-3911|\
smartrg,sdg-8622|\
smartrg,sdg-8632|\
diff --git a/target/linux/mediatek/filogic/base-files/etc/hotplug.d/ieee80211/11_fix_wifi_mac b/target/linux/mediatek/filogic/base-files/etc/hotplug.d/ieee80211/11_fix_wifi_mac
index b0b301559b..4a107940ec 100644
--- a/target/linux/mediatek/filogic/base-files/etc/hotplug.d/ieee80211/11_fix_wifi_mac
+++ b/target/linux/mediatek/filogic/base-files/etc/hotplug.d/ieee80211/11_fix_wifi_mac
@@ -97,6 +97,10 @@ case "$board" in
addr=$(mtd_get_mac_binary "Odm" 0x81)
[ "$PHYNBR" = "1" ] && macaddr_add $addr 3 > /sys${DEVPATH}/macaddress
;;
+ dlink,x530-a1)
+ addr=$(mtd_get_mac_binary "Odm" 0x95)
+ [ "$PHYNBR" = "1" ] && macaddr_add $addr 3 > /sys${DEVPATH}/macaddress
+ ;;
glinet,gl-mt6000|\
glinet,gl-x3000|\
glinet,gl-xe3000)
diff --git a/target/linux/mediatek/filogic/base-files/lib/upgrade/platform.sh b/target/linux/mediatek/filogic/base-files/lib/upgrade/platform.sh
index 3cc8b91b74..ef5a6f5d3e 100755
--- a/target/linux/mediatek/filogic/base-files/lib/upgrade/platform.sh
+++ b/target/linux/mediatek/filogic/base-files/lib/upgrade/platform.sh
@@ -139,7 +139,8 @@ platform_do_upgrade() {
default_do_upgrade "$1"
;;
dlink,aquila-pro-ai-m30-a1|\
- dlink,aquila-pro-ai-m60-a1)
+ dlink,aquila-pro-ai-m60-a1|\
+ dlink,x530-a1)
fw_setenv sw_tryactive 0
nand_do_upgrade "$1"
;;
diff --git a/target/linux/mediatek/image/filogic.mk b/target/linux/mediatek/image/filogic.mk
index 78e77ea28d..010fece3df 100644
--- a/target/linux/mediatek/image/filogic.mk
+++ b/target/linux/mediatek/image/filogic.mk
@@ -912,6 +912,26 @@ endif
endef
TARGET_DEVICES += dlink_aquila-pro-ai-m60-a1
+define Device/dlink_x530-a1
+ DEVICE_VENDOR := D-Link
+ DEVICE_MODEL := X530
+ DEVICE_VARIANT := A1
+ DEVICE_DTS := mt7981b-dlink-x530-a1
+ DEVICE_DTS_DIR := ../dts
+ DEVICE_PACKAGES := kmod-leds-gca230718 kmod-mt7915e kmod-mt7981-firmware mt7981-wo-firmware
+ KERNEL_IN_UBI := 1
+ IMAGE_SIZE := 51200k
+ IMAGE/sysupgrade.bin := sysupgrade-tar | append-metadata
+ifeq ($(IB),)
+ifneq ($(CONFIG_TARGET_ROOTFS_INITRAMFS),)
+ IMAGES += recovery.bin
+ IMAGE/recovery.bin := append-image-stage initramfs-kernel.bin | sysupgrade-tar kernel=$$$$@ |\
+ pad-to $$(IMAGE_SIZE) | dlink-ai-recovery-header DLK6E6110001 \x6A\x28\xEE\x0B \x00\x00\x2C\x00 \x00\x00\x20\x03 \x61\x6E
+endif
+endif
+endef
+TARGET_DEVICES += dlink_x530-a1
+
define Device/edgecore_eap111
DEVICE_VENDOR := Edgecore
DEVICE_MODEL := EAP111
and also added an extracted DTS file to:
openwrt > target > linux > mediatek > dts > mt7981b-dlink-x530-a1.dts
The kernel compiled, but when it is booting, it freezes after "disabling unused clocks":
https://pastebin.com/FrcWXGvC
The kernel boots if I use
openwrt-24.10.4-mediatek-filogic-dlink_aquila-pro-ai-m30-a1-initramfs-kernel
so obviously there is something that is wrong
From the last boot message I assume that the kernel disables the clock on which the CPU is running but this is only my guess, and I don't really know how to approach it further.
At the beginning I assumed that - because the hardware platform is different - lots of differences, including GPIO should be covered by the "right" DTS file, but obviously it was not enough.
How to go further from here?