R4 variants NAND partition mess

[LynxChaus]

Hi.
Can you explain this big mess with NAND partitions for R4 variants?
for r4-lite partition@20000 defined and described as UBI with volumes:

BPI-Router-Linux/arch/arm64/boot/dts/mediatek/mt7987a-bananapi-bpi-r4-lite-nand.dtso

Line 36 in 445521c

partition@200000 {

for 4r-pro partition@20000 defined as UBI but without volumes:

BPI-Router-Linux/arch/arm64/boot/dts/mediatek/mt7988a-bananapi-bpi-r4-pro.dtsi

Line 637 in 445521c

partition@200000 {

for r4 partition@20000 not defined at all:

BPI-Router-Linux/arch/arm64/boot/dts/mediatek/mt7988a-bananapi-bpi-r4.dtsi

Line 477 in 445521c

partitions {

Default enviroment for R4 contains wrspimnand command https://github.com/frank-w/u-boot/blob/d434af53965f02625dc2f07bb2767f3508449883/uEnv_r4.txt#L77 which write fip image to 0x580000 offset.
But, if NAND designed for contain UBI image, writing fip destroy UBI internals, isn't it?
Or this command leftover from R3 variant? If not - why partitions not described int dts?

[frank-w]

the wrspimnand command in uboot-env is an older version (static offsets and without ubi/mtd) to get fast nand-boot to only get into uboot for loading kernel/initramfs manually only for flashing emmc. for UBI this is more complex and requires image created before.

https://github.com/frank-w/BPI-Router-Images/#how-to-build-nand-image

https://github.com/frank-w/BPI-Router-Images/#nand