Linux/AM4378: after sf write sth,i sf read,but it isn.t the same .

Tool/software: Linux

i want load uImage and dtb to qspi chip, so i do as below

fatload mmc 0 80000000 uImage
sf probe
sf erase 100000 800000
sf write 80000000 100000 800000

then i try to read sth from qspi at the addr i write before,but it isn'y the same with i write in

sf read 90000000 100000 800000

what's wrong maybe??

i cut some picture