On P8, XSCOM addresses has a special "indirect" form that
requires more than 32-bits, so let's use u64 everywhere in
the code instead of u32.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
scom_read() now returns the read value via a pointer argument and
both functions return an int error code
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
SCOM is a side-band configuration bus implemented on some processors.
This code provides a way for code to map and operate on devices via
SCOM, while the details of how that is implemented is left up to a
SCOM "controller" in the platform code.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Benjamin Herrenschmidt