arch: Unify basic cache clearing API

Caching is a very architecture-specific thing, but most architectures
have a cache in general. Therefore it can be useful to have a generic
architecture-independent API to perform simple cache management tasks
from common code.

We have already standardized on the dcache_clean/invalidate naming
scheme that originally comes from ARM in libpayload, so let's just do
the same for coreboot. Unlike libpayload, there are other things than
just DMA coherency we may want to achieve with those functions, so
actually implement them for real even on architectures with
cache-snooping DMA like x86. (In the future, we may find applications
like this in libpayload as well and should probably rethink the API
there... maybe move the current functionality to a separate
dma_map/unmap API instead. But that's beyond scope of this patch.)

Change-Id: I2c1723a287f76cd4118ef38a445339840601aeea
Signed-off-by: Julius Werner <>
Tested-by: build bot (Jenkins) <>
Reviewed-by: Aaron Durbin <>
Reviewed-by: Philippe Mathieu-Daudé <>
4 files changed