Content originally posted in LPCWare by cfb on Sat Nov 22 23:02:11 MST 2014
Did you notice this section? It doesn't say where the cache is but it does explain how you can have some control over it:
19.6.5 SPIFI cache limit register
The SPIFI hardware includes caching of previously-accessed data to improve performance. Software can write an address within the device to this register, to prevent such caching at and above that address. After Reset this register contains the allocated size of the SPIFI memory area, so that all possible accesses are below that value and are thus cacheable.
SPIFI cache limit register (CLIMIT, address 0x4000 3010)