FreeBSD/arm64 becoming Tier 1 in FreeBSD 13

[Ed Maste]

Summary

FreeBSD will promote arm64 to a Tier 1 architecture in FreeBSD 13.
This means we will provide release images, binary packages, and
security and errata updates. While we anticipate there will be minor
issues with this first release, we believe the port is mature enough
that they can be resolved during the life of FreeBSD 13.

Details

Development efforts on FreeBSD/arm64 (also known as AArch64) started
in 2014, with generous financial and technical support from Arm,
Cavium and the FreeBSD Foundation. FreeBSD 11.0 arrived in October
2016 as the first release with support for the architecture.
Improvements to the kernel, tool chain, userland, and ports and
package infrastructure have been ongoing since that time, with
improvements arriving in each minor and major release.

The FreeBSD base system is ready for the promotion of arm64 to Tier 1,
and the Release Engineering, Security, and Ports teams are prepared to
support the Tier 1 requirements for arm64. Security updates via
freebsd-update now include arm64 support (starting with the FreeBSD
13.0 release candidates).

Required ports infrastructure is in place for arm64 and most ports
build successfully. The project now has several Ampere eMAG systems
acting as package build servers. These machines were obtained through
a combination of FreeBSD Foundation purchases and generous donations
from Ampere.

To support port maintainers who do not have access to arm64 hardware
we will be improving ports CI and testing resources (and this effort
will benefit all architectures). We will also be suggesting one or
more low-cost reference platforms for FreeBSD/arm64.

The guarantees included in Tier 1 status are described in
https://docs.freebsd.org/en_US.ISO8859-1/articles/committers-guide/archs.html

In particular, for Tier 1 architectures the project provides release
images, binary package sets, and binary and source updates for
Security Advisories and Errata Notices.

The AArch64 ecosystem’s maturity ensures follow on generations of
hardware. The diversity of offerings, as well as the multiple
generations of hardware shows that the FreeBSD project will benefit
from adding support for this platform. The growth trajectory suggests
this will be a significant portion of the market in the coming years,
and FreeBSD will benefit from tapping into this market with this Tier
1 platform.

(on behalf of core)