Most modern caches do not store data as a sequential fragment of bytes, but use banking and interleaving methods due to the nature of the plan or time. In addition, most caches use error correction methods, so additional bits can be interleaved with data.
As a result, it makes no sense to discuss cache consistency, since the internal order is usually distorted by design considerations. In addition, in most cases, caches provide data in full-size detail, so it also makes no sense to ask what offset you start reading.
Finally, endianness is a matter of architecture, this is how you interpret the data received from the CPU. It exists to describe the possible options that you can interpret in the data. Caches are micro-architectural, so by definition your functional processor behavior should not be addressed to them, and they can freely execute any internal structure that they want. The question may still make sense if you have some way to look inside the cache, and he would like to translate it into a value, in which case the above consideration applies, and each processor may differ.
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