iPXE does insert stub BLOCK IO protocol handle to rework other issues,
this handle is not usable as it does not provide actual implementation.
We can detect this situation by checking and validating the BlockSize
property, so this update does make sure we have BlockSize at least 512B
and its value is power of 2.
PR: 223969
Reported by: Jeff Pieper
Reviewed by: imp
Differential Revision: https://reviews.freebsd.org/D13297
Rework the block device handle check to allow more robust device
classification. This is mostly usability issue - it can be quite confusing
for user when no disks are listed with lsdev.
Add more comments about what and why is done.
Reviewed by: imp
Differential Revision: https://reviews.freebsd.org/D13026
simd / no float stuff is centeralized here. Also centralise
-ffreestanding since it is specified everywhere.
This, along with a change to share/mk/bsd.cpu.mk to include -mno-avx2
in CFLAGS_NO_SIMD should fix building for newer machines (eg with
CPUTYPE=haswell) where clang was generating avx2 instructions.
Sponsored by: Netflix
