compared to bpi-r3 fip is at position 0x580000

BPI-R4> ls mmc 0:5
  9010412   6.7.0-rc3-dango.itb
      127   uEnv.txt
  9025092   6.6.0-rc2-dango.itb
 24735843   6.6.0-r4-dango
  8941016   6.6.0-r4-dango.itb
  9080636   6.8.0-rc3-dango.itb
 32890100   rootfs_arm64.cpio.gz
   254821   bpi-r4_spim-nand_bl2.img
  9031768   6.7.0-rc5-dango_2.itb
   278533   bpi-r4_spim-nand_fip.bin

10 file(s), 0 dir(s)

BPI-R4> mtd erase spi-nand0
spi-nand: spi_nand spi_nand@0: Winbond SPI NAND was found.
spi-nand: spi_nand spi_nand@0: 128 MiB, block size: 128 KiB, page size: 2048, O4
Erasing 0x00000000 ... 0x07ffffff (1024 eraseblock(s))
BPI-R4> fatload mmc 0:5 $loadaddr bpi-r4_spim-nand_bl2.img
254821 bytes read in 19 ms (12.8 MiB/s)
BPI-R4> mtd write spi-nand0 $loadaddr 0x0 0x100000
Writing 1048576 byte(s) (512 page(s)) at offset 0x00000000
BPI-R4> fatload mmc 0:5 $loadaddr bpi-r4_spim-nand_fip.bin
278533 bytes read in 20 ms (13.3 MiB/s)                                         
BPI-R4> mtd write spi-nand0 $loadaddr 0x580000 0x200000                         
Writing 2097152 byte(s) (1024 page(s)) at offset 0x00580000                     
BPI-R4> reset                                                                   
resetting ...