Hardfloat is now default (use riscv64sf as TARGET_ARCH
for softfloat).
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D8529
Machine privilege level was specially designed to use in vendor's
firmware or bootloader. We have implemented operation in machine
mode in FreeBSD as part of understanding RISC-V ISA, but it is time
to remove it.
We now use BBL (Berkeley Boot Loader) -- standard RISC-V firmware,
which provides operation in machine mode for us.
We now use standard SBI calls to machine mode, instead of handmade
'syscalls'.
o Remove HTIF bus.
HTIF bus is now legacy and no longer exists in RISC-V specification.
HTIF code still exists in Spike simulator, but BBL do not provide
raw interface to it.
Memory disk is only choice for now to have multiuser booted in Spike,
until Spike has implemented more devices (e.g. Virtio, etc).
Sponsored by: DARPA, AFRL
Sponsored by: HEIF5
Tested on Spike simulator with 2 and 16 cores (tlb enabled),
so set MAXCPU to 16 at this time.
This uses FDT data to get information about CPUs
(code based on arm64 mp_machdep).
Invalidate entire TLB cache as it is the only way yet.
Sponsored by: DARPA, AFRL
Sponsored by: HEIF5
