One of the functions of the ADU is indirect memory access engines that
send and receive data via ADU registers.
This implements the ADU LPC memory access functionality sufficiently
for IBM proprietary firmware to access the UART and print characters
to the serial port as it does on real hardware.
This requires a linkage between adu and lpc, which allows adu to
perform memory access in the lpc space.
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
This implements a framework for an ADU unit model.
The ADU unit actually implements XSCOM, which is the bridge between MMIO
and PIB. However it also includes control and status registers and other
functions that are exposed as PIB (xscom) registers.
To keep things simple, pnv_xscom.c remains the XSCOM bridge
implementation, and pnv_adu.c implements the ADU registers and other
functions.
So far, just the ADU no-op registers in the pnv_xscom.c default handler
are moved over to the adu model.
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Nicholas Piggin