Currently the IHC (Inter Hart Communication) depends on OpenAMP and
rptun. However, the bootloader portion of the IHC doesn't need
either of them. Now they are wasting a lot of bootloader space.
Reorganize the bootloader portion into a separate file 'mpfs_ihc_sbi.c'.
This file contains the OpenSBI vendor extensions, or the only required
functionalities for the bootloader. On the other hand, 'mpfs_ihc.c'
contains the non-bootloader code.
This patch also makes it possible to utilize 2 RPMSG channels. This
has been tested so that 2 separate NuttXs on harts 1 and 2 communicate
with Linux kernel that runs on harts 3 and 4.
New configuration files are added as well:
- rpmsg-ch1: sample config for RPMSG
- rpmsg-ch2: sample config for another RPMSG channel
- rpmsg-sbi: sample bootloader config for RPMSG/OpenSBI
Signed-off-by: Eero Nurkkala <eero.nurkkala@offcode.fi>
