Unlike the other Sun machines, UltraSPARCs can have consoles run on different
chips than zs, so we need to support them. So, here we go:
Add a new PROM console driver with a major number and everything.
This is the default driver if nothing else attaches. It does not
use the keyboard driver since the PROM translates keystrokes itself.
(Unfortunately it also swallows L1-A).
Have the keyboard driver take over the console when it attaches on a
serial port. When a serial port detects a keyboard and attaches the
keyboard driver, it needs to provide a set of consdev vectors. They
keyboard driver will use those to send I/O to the keyboard and mouse.
timeout()/untimeout() API:
- Clients supply callout handle storage, thus eliminating problems of
resource allocation.
- Insertion and removal of callouts is constant time, important as
this facility is used quite a lot in the kernel.
The old timeout()/untimeout() API has been removed from the kernel.
* do not require a `zs' driver for console handling
* run the console on PROM primitives until a device recognises
itself as a console device during normal autoconfiguration.
* allow (keyboard) devices to take over the input channel of
the PROM primitive-based console device.
As a result, consinit() is much simplified and does no longer have
to "detect" devices to setup a working console device. This complexity
has moved to individual drivers which interpret the PROM information
after they have attached to decide whether or not to act as a console.
that is priority is rasied. Add a new spllowersoftclock() to provide the
atomic drop-to-softclock semantics that the old splsoftclock() provided,
and update calls accordingly.
This fixes a problem with using the "rnd" pseudo-device from within
interrupt context to extract random data (e.g. from within the softnet
interrupt) where doing so would incorrectly unblock interrupts (causing
all sorts of lossage).
XXX 4 platforms do not have priority-raising capability: newsmips, sparc,
XXX sparc64, and VAX. This platforms still have this bug until their
XXX spl*() functions are fixed.
eeh