Quick fix for calling DELAY() for ddb input in some (atkbd-based)
console drivers. ddb must not use any normal locks, but DELAY()
normally calls getit() which needs clock_lock. One problem with using
normal locks in ddb is that deadlock is possible, but deadlock on
clock_lock is unlikely becaluse clock_lock is bogusly recursive,
apparently just to hide the problem of ddb using it. The i8254 clock
hardware has mostly write-only registers so it is important for it to
use a lock that gives exclusive access. (atkbd hardware is also
unfriendly to reentrant software but that problem is more local and
already solved.) I mostly saw the symptoms of the bug caused by
unlocking in getit() running cpu_unpend(). cpu_unpend() should not
be called while in ddb and Debugger() calls for failing assertions
about this caused a breakpoint within ddb.
ddb must also not call getit() because ddb may be being used to step
through clock initialization code that has stopped or otherwise mangled
the clock. If the clock is stopped, then getit() always returns the
same value and DELAY() takes forever if it trusts getit().
The quick fix is implement DELAY(n) as (n * timer_freq / 1000000)
inb(0x84)'s if ddb is active.
machdep.c:
Don't permit recursion on clock_lock.
as it was decided that our toolchain will revert to looking
for libraries in /usr/lib only.
- Make /usr/lib/libfoo.so -> /lib/libfoo.so.X symlinks absolute
so that they still work if /usr is symlinked.
- Remove stale /usr/lib/libfoo.so.X libraries during install.
Discussed with: gordon, obrien, peter
kdb_trap(). Stopping the other CPUs acts like locking them out, but
it wasn't done early enough or held long enough to prevent concurrent
accesses to shared data. In particular, the saved regs could be
clobbered.
with 64-bit longs again. This was fixed in rev.1.42 but the fix
rotted non-fatally in rev.1.105 and fatally in rev.1.137.
Many more non-egregrious casts are strictly required for conversions
from semi-opaque types to pointers, but we avoid most of them by using
types that are almost certain to be compatible with uintptr_t for
representing pointers (e.g., vm_offset_t). Here we don't really want
the u_longs, but we have them because a.out.h and its support code
doesn't use typedefs (it uses unsigned in V7 and unsigned long in
FreeBSD) and is too obsolete to fix now.
FIDs to be 128-bits wide and adds support for realms.
Add a new CODA_COMPAT_5 option, which requests support for the old
Coda 5.x interface instead of the new one.
Create a new coda5.ko module that supports the 5.x interface, and make
the existing coda.ko module use the new 6.x interface. These modules
cannot both be loaded at the same time.
Obtained from: Jan Harkes & the coda-6.0.2 distribution,
NetBSD (drochner) (CODA_COMPAT_5 option).
device special files created by sio(4). The latter are the device
special files created by uart(4). As of this moment sio(4) is not
supported on ia64... by me, that is :-)
building a module. Inclusion of option files (opt_ddb.h in this
case) is not possible for modules. The inclusion of opt_ddb.h
in this header is questionable.
(ns8250 copied and s/ns8250/i8251/g), but there for linkage purposes.
Real code to follow, once I get past some boot issues on my pc98 boxes
with recent current.
of what uart(4) is and/or is not see the initial commit log of one
of the files in sys/dev/uart (or see share/man/man4/uart.4).
Note that currently pc98 shares the MD file with i386. This needs
to change when pc98 support is fleshed-out to properly support the
various UARTs. A good example is sparc64 in this respect.
We build uart(4) as a module on all platforms. This may break
the ppc port. That depends on whether they do actually build
modules.
To use uart(4) on alpha, one must use the NO_SIO option.
It improves on sio(4) in the following areas:
o Fully newbusified to allow for memory mapped I/O. This is a must
for ia64 and sparc64,
o Machine dependent code to take full advantage of machine and firm-
ware specific ways to define serial consoles and/or debug ports.
o Hardware abstraction layer to allow the driver to be used with
various UARTs, such as the well-known ns8250 family of UARTs, the
Siemens sab82532 or the Zilog Z8530. This is especially important
for pc98 and sparc64 where it's common to have different UARTs,
o The notion of system devices to unkludge low-level consoles and
remote gdb ports and provides the mechanics necessary to support
the keyboard on sparc64 (which is UART based).
o The notion of a kernel interface so that a UART can be tied to
something other than the well-known TTY interface. This is needed
on sparc64 to present the user with a device and ioctl handling
suitable for a keyboard, but also allows us to cleanly hide an
UART when used as a debug port.
Following is a list of features and bugs/flaws specific to the ns8250
family of UARTs as compared to their support in sio(4):
o The uart(4) driver determines the FIFO size and automaticly takes
advantages of larger FIFOs and/or additional features. Note that
since I don't have sufficient access to 16[679]5x UARTs, hardware
flow control has not been enabled. This is almost trivial to do,
provided one can test. The downside of this is that broken UARTs
are more likely to not work correctly with uart(4). The need for
tunables or knobs may be large enough to warrant their creation.
o The uart(4) driver does not share the same bumpy history as sio(4)
and will therefore not provide the necessary hooks, tweaks, quirks
or work-arounds to deal with once common hardware. To that extend,
uart(4) supports a subset of the UARTs that sio(4) supports. The
question before us is whether the subset is sufficient for current
hardware.
o There is no support for multiport UARTs in uart(4). The decision
behind this is that uart(4) deals with one EIA RS232-C interface.
Packaging of multiple interfaces in a single chip or on a single
expansion board is beyond the scope of uart(4) and is now mostly
left for puc(4) to deal with. Lack of hardware made it impossible
to actually implement such a dependency other than is present for
the dual channel SAB82532 and Z8350 SCCs.
The current list of missing features is:
o No configuration capabilities. A set of tunables and sysctls is
being worked out. There are likely not going to be any or much
compile-time knobs. Such configuration does not fit well with
current hardware.
o No support for the PPS API. This is partly dependent on the
ability to configure uart(4) and partly dependent on having
sufficient information to implement it properly.
As usual, the manpage is present but lacks the attention the
software has gotten.
o Introduce PUC_PORT_TYPE_UART so that we can attach to uart(4),
o Introduce port sub-types (eg PUC_PORT_UART_NS8250, PUC_PORT_UART_Z8530)
to handle different hardware and determine resource sizes.
o Introduce two new IVARs: PUC_IVAR_SUBTYPE and PUC_IVAR_REGSHFT. Both
are used by uart(4) to get sufficient information to talk to the HW.
o Introduce PUC_FLAGS_ALTRES to tell puc(4) to try memory mapped I/O
if I/O port space cannot be allocated, or vice versa.
o Have ports of type PUC_PORT_TYPE_COM attach to uart(1) if attaching
to sio(4) fails (due to not having the sio driver).
o Put struct puc_device_description in struct puc_softc instead of
having a pointer to a device description in the softc. This allows
us to create device descriptions on the fly without having to use
malloc() or otherwise have them staticly defined.
o Move puc_find_description() from puc.c to puc_pci.c as it's specific
to PCI.
o Add EBUS and SBUS frontends for use on sparc64. Note that the P in
puc stands for PCI, so we kinda mess things up here. It's too soon
to worry about it though. We'll know what to do about it in time.
NOTE: This commit changes the behaviour of puc(4) to not quieten the
device probe and attach for child devices. The uart(4) driver provides
additional device description that is valuable to have.
