some question about TCR setting

[vichy]

hi all:
from armv8 spec, no matter TCR_EL1/2/3, there are
1. SH (shareability)
2. ORGN (outer cacheability)
3. IRGN(inner cacheability)

but in the each level block/page descriptor, there are also
sharability, inner, outter, cacheability as well.

What is the difference between the sharability, inner/outer
cacheability between TCR and Block/page descriptors?

Why are there attributes setting keep in TCR?

appreciate your kind help in advance,