Free approx 86 major numbers with a mostly automatically generated patch.
A number of strategic drivers have been left behind by caution, and a few
because they still (ab)use their major number.
with multiple ports on a shared interrupt demultiplexed by the puc_intr()
handler.
siointr1() first read as much input as possible and then checked all
possibly-relevant status registers, partly for robustness and partly
for historical reasons. This is very bad if it is called for every
port sharing an interrupt like puc_intr() does. It can spend too long
reading all the input for some ports when the interrupt is for a more
urgent event on another, or just too long checking all the status
registers when there are lots of ports. The inter-character time is
too long for reading all the input even when the interrupt is for a
transmitter interrupt on the same port, and at 921600 bps the inter-char
time is 10.85 usec and was often exceeded with just 2 ports, leaving
the transmitters idle for about 6% of the time.
The tweak is to break out of the read loop after reading 1 char if
output can be done. This avoids most of the idle transmitter time for
2 active ports at 921600 bps bidirectional on the test system. It
also reduces overhead by about 20%. More complete fixes use the
programmable tx low watermark on 16950's and reduce overhead by another
65%.
will now need editing except for spot checks.
Changed this buffer from a circular one to a linear one. This is more
useful for some cases and the sysctl that prints it doesn't support
circular buffers.
Fixed (output) formatting bugs in this sysctl. An off by 1 error caused
a garbage byte to be returned after annotation of large deltas, and
a race with the writer sometimes caused premature string termination.
from fiddling with CS_TTGO since fiddling with CS_TTGO was removed in
rev.1.218 of the i386/isa version (which was merged with loss of history
in rev.1.223 of this version).
- Removed conversion of a zero input speed to the output speed. This
has been done better in ttioctl() since rev.1.108 of kern/tty.c
almost 5 years ago. comparam() did the conversion incompletely for
the case where the output speed is also zero. It had complications
to avoid using zero speeds, but would still have used a zero input
speed for setting watermarks if kern/tty.c had passed one.
- Never permit the input speed to be different from the output speed.
There was no validity check on the input speed for the case of a zero
output speed. Then we didn't change the physical speeds, but we used
the unvalidated input speed for setting watermarks and didn't return
an error, so ttioctl() stored the unvalidated input speed in the tty
struct where it could cause problems later.
- Removed complications that were to avoid using a divisor of 0. The
divisor is now always valid if the speed is accepted.
in the loopback test in the probe. The delay was too short for consoles
at speeds lower than about 3200 bps. This shouldn't have caused many
problems, since such low speeds are rare and the probe is forced to
succeed for consoles.
COM_NOFIFO() and COM_ESP cases are supposed to be a subsets of the
plain 16550A case, but 16650-related changes made the former fall into
the latter and then both fall into general code for printing the tx
fifo size. This mainly caused hard to parse boot messages like:
"sio0: type 16550A fifo disabled lookalike with 1 bytes FIFO".
COM_NOFIFO() on an ESP port gave a larger mess whose extent is not
clear.
Fixed some nearby style bugs.
defined values instead of hard-coded values. Don't repeat the register
access part of the code 4 times times or triple-space statements. This
fixes half of the style bugs in rev.1.172.
Hardware flow control of 16650As is still officially unsupported. I
was mistaken about it being broken. It is broken in 16650s but is
fixed in 16650As except for the maximum trigger level (which is no
longer used). Testing of the 16650's broken hardware flow control
watermarks by programming them on 16950s showed that their effects are
not too bad if the fifo size and trigger level are reasonably large
(16 is much better than 8).
was added to the fast path to support the COM_IIR_RXRDYBUG() case even
when that case is not configured. This increased the relative overhead
of sio input by almost 25% in the worst case and by 2-3% in the usual
case (usually only about 0.2% absolute per port at 115200 bps). The
quick fix is to significantly pessimize only the COM_IIR_RXRDYBUG()
case.
disabled.
- Change the apm driver to match the acpi driver's behavior by checking to
see if the device is disabled in the identify routine instead of in the
probe routine. This way if the device is disabled it is never created.
Note that a few places (ips(4), Alpha SMP) used "disable" instead of
"disabled" for their hint names, and these hints must be changed to
"disabled". If this is a big problem, resource_disabled() can always be
changed to honor both names.
now unnecessary hack from the previous commit;
- Add support for Interrupt Latch Register (ILR) into puc(4). So far only
ILRs compatible with specifications from Digi International are supported.
Support for other types of ILRs could be easily added later;
- Correct clock frequency for IC Book Labs Dreadnought x16 Lite board;
- Enable ILR detection/usage for IC Book Labs Dreadnought x16 boards.
Sponsored by: IC Book Labs
MFC after: 2 weeks
this card is based on 16750 UART, modify sio(4) a bit to ignore 16750-specific
7th bit of MCR when probing card. This allows card to be detected and attached
as 16550A-compatible device. More work needs to be done in order to enable
nice 16750-specific features such as larger fifo buffer and higher speeds.
Sponsored by: IC Book Labs
MFC after: 2 weeks
branches:
Initialize struct cdevsw using C99 sparse initializtion and remove
all initializations to default values.
This patch is automatically generated and has been tested by compiling
LINT with all the fields in struct cdevsw in reverse order on alpha,
sparc64 and i386.
Approved by: re(scottl)
dev_t to the method functions.
The dev_t can still be found at struct consdev *->cn_dev.
Add a void *cn_arg element to struct consdev which the drivers can use
for retrieving their softc.
The advanced stage of computer assisted hardware design and
verification is aptly illustrated by the fact that this is necessary
because only the first ports in a single-chip, dual-port async
PC-Card product lacks this register.
This facilitates the use in circumstances where you are using a serial
console as well. GDB doesn't support anything higher than 9600 baud (19k2
if you are lucky), but the console does.
most cases NULL is passed, but in some cases such as network driver locks
(which use the MTX_NETWORK_LOCK macro) and UMA zone locks, a name is used.
Tested on: i386, alpha, sparc64
general cleanup of the API. The entire API now consists of two functions
similar to the pre-KSE API. The suser() function takes a thread pointer
as its only argument. The td_ucred member of this thread must be valid
so the only valid thread pointers are curthread and a few kernel threads
such as thread0. The suser_cred() function takes a pointer to a struct
ucred as its first argument and an integer flag as its second argument.
The flag is currently only used for the PRISON_ROOT flag.
Discussed on: smp@
(65536 * 32 - 1), but MAKEDEV only supports up to (32 * 32 -1). Device
names use the unit number in base 32 for all "digits".
This required fixing an old bug in MAKEDEV:ttyminor(). Its arg was the
global $unit instead of $1.
Reminded by: Valentin K. Ponomarenko <valka@krog.ukrtel.net>
MFC-after: 1 week
measured accurately for periodic interrupts provided the interrupts
don't need to be serviced very quickly to keep their period almost
constant. sio output interrupts have this property (interrupt service
can be delayed for up to 1 character time without the period changing).
This is non-optional and undocumented so that it can be added and
removed easily. It has no significant effect unless it is enabled by
hacking on a variable using a debugger. Hardclock and statclock interrupts
would work even better for this, at least on i386's, provided their
interrupt handlers are fast (as they are in -current but not in -stable
or in my version of -current).
not removing tabs before "__P((", and not outdenting continuation lines
to preserve non-KNF lining up of code with parentheses. Switch to KNF
formatting and/or rewrap the whole prototype in some cases.
to put the device into 8 bit mode a second time. This appears to have
no ill effects on other devices, and appears to be necessary for the
xircom modem.
Submitted by: gwk@sgi.com, many others that found his patch in the archives.
previous commit, it should always print due to lack of {} around the
second line in the if statement. The message should likely say
something more like "There's no hardware responding at this IRQ.
Device not present (or disbaled)," but that is too long. We generally
don't give elementary advise in device driver messages anyway. Be
that as it may, the problem with it printing all the time should be
corrected.
mutex releases to not require flags for the cases when preemption is
not allowed:
The purpose of the MTX_NOSWITCH and SWI_NOSWITCH flags is to prevent
switching to a higher priority thread on mutex releease and swi schedule,
respectively when that switch is not safe. Now that the critical section
API maintains a per-thread nesting count, the kernel can easily check
whether or not it should switch without relying on flags from the
programmer. This fixes a few bugs in that all current callers of
swi_sched() used SWI_NOSWITCH, when in fact, only the ones called from
fast interrupt handlers and the swi_sched of softclock needed this flag.
Note that to ensure that swi_sched()'s in clock and fast interrupt
handlers do not switch, these handlers have to be explicitly wrapped
in critical_enter/exit pairs. Presently, just wrapping the handlers is
sufficient, but in the future with the fully preemptive kernel, the
interrupt must be EOI'd before critical_exit() is called. (critical_exit()
can switch due to a deferred preemption in a fully preemptive kernel.)
I've tested the changes to the interrupt code on i386 and alpha. I have
not tested ia64, but the interrupt code is almost identical to the alpha
code, so I expect it will work fine. PowerPC and ARM do not yet have
interrupt code in the tree so they shouldn't be broken. Sparc64 is
broken, but that's been ok'd by jake and tmm who will be fixing the
interrupt code for sparc64 shortly.
Reviewed by: peter
Tested on: i386, alpha
(1) Don't attempt aquire the non-recursive lock sio_lock recursively.
Doing so caused unbounded recursion in some setups. E.g., if DDB,
BREAK_TO_DEBUGGER and WITNESS are configured; if the debugger is
entered using a break, then WITNESS will actually detect the invalid
recursion and will add to it attempting to print a message about it.
(2) Don't use sio_lock before it has been initialized. The old check
(sio_inited != 0) didn't work when sio_inited was boolean because
sio_inited was set too early, and became just wrong when sio_inited
was changed to a tri-state variable in rev.1.348.
Reported and fixed in another way by: fenner (1)
see people trip over it. Do not set the FIFO trigger to just before it
would otherwise overflow. Give it a little more slop so characters aren't
lost if the interrupt is delayed by other system activities.
MFC maybe: 7 days
allows us to move the sio softc data structure back into sio.c and
reduce the complexity of the non sio.c sio files.
Submitted by: bde
# I didn't fix the locking issues that bruce also submitted.
sio_pccard_detach to use new siodetach. Add an extra arg to sioprobe
to tell driver to probe/not probe the device for IRQs.
This incorporates most of Bruce's review material. I'm at a good
checkpoint, but there will be more to come based on bde's further
reviews.
Reviewed by: bde
Move sio from isa/sio.c to dev/sio/sio.c. The next step is to break
out the front end attachments, improve support for these parts on
different busses, and maybe, if we're lucky, merging in pc98 support.
It will also be MI and live in conf/files rather than files.*.
Approved by: bde
Tested with: i386, pc98
sio_lock has been initialized. This prevents the low level console
output (kernel printf) from clobbering the sio settings if the system
happens to be in the middle of comstart().
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.
Sorry john! (your next MFC will be a doosie!)
Reviewed by: peter@freebsd.org, dillon@freebsd.org
X-MFC after: ha ha ha ha
to properly clear the interrupt register on the no error case. Also,
set the mcr register to zero when we find we can't support the chip.
This fixes the hang on sio driver attach problem in the new pci pccard
code that some people have reported. At least on my machine. I'd
like to get this into 4.4.
Submitted by: bde
PR: kern/29742
MFC after: 1 day
the console device was open. At other times, the interrupts that
are used to detect the break signal or ~^B sequence were disabled,
so these events would not be noticed until the next open (e.g. the
next kernel printf). This was mainly a problem while there was no
getty running on the console, such as during bootup or shutdown.
For serial consoles with break-to-debugger support, we now enable
the generation of interrupts at attach time, and we leave them
enabled while the device is closed.
Reviewed by: bde (I've since made chages as per his suggestions)
I think bde even reviewed it once.
Also, change the name of ActionTEC pat to more generic Lucent Kermit
chip. Add stub for Xircom card. Add cardbus attachment too.
can be made userland-visible as <dev/ic/...>. Also, those files are
not supposed to contain any bus-specific details at all, so placing
them under .../isa/ has been a misnomer from the beginning.
The files in src/sys/dev/ic/ have been repo-copied from their old
location (this commit is a forced null commit there to record this
message).
other "system" header files.
Also help the deprecation of lockmgr.h by making it a sub-include of
sys/lock.h and removing sys/lockmgr.h form kernel .c files.
Sort sys/*.h includes where possible in affected files.
OK'ed by: bde (with reservations)
Some things needed bits of <i386/include/lock.h> - cy.c now has its
own (only) copy of the COM_(UN)LOCK() macros, and IMASK_(UN)LOCK()
has been moved to <i386/include/apic.h> (AKA <machine/apic.h>).
Reviewed by: jhb
- Use swi_* function names.
- Use void * to hold cookies to handlers instead of struct intrhand *.
- In sio.c, use 'driver_name' instead of "sio" as the name of the driver
lock to minimize diffs with cy(4).
mtx_enter(lock, type) becomes:
mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks)
mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized)
similarily, for releasing a lock, we now have:
mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN.
We change the caller interface for the two different types of locks
because the semantics are entirely different for each case, and this
makes it explicitly clear and, at the same time, it rids us of the
extra `type' argument.
The enter->lock and exit->unlock change has been made with the idea
that we're "locking data" and not "entering locked code" in mind.
Further, remove all additional "flags" previously passed to the
lock acquire/release routines with the exception of two:
MTX_QUIET and MTX_NOSWITCH
The functionality of these flags is preserved and they can be passed
to the lock/unlock routines by calling the corresponding wrappers:
mtx_{lock, unlock}_flags(lock, flag(s)) and
mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN
locks, respectively.
Re-inline some lock acq/rel code; in the sleep lock case, we only
inline the _obtain_lock()s in order to ensure that the inlined code
fits into a cache line. In the spin lock case, we inline recursion and
actually only perform a function call if we need to spin. This change
has been made with the idea that we generally tend to avoid spin locks
and that also the spin locks that we do have and are heavily used
(i.e. sched_lock) do recurse, and therefore in an effort to reduce
function call overhead for some architectures (such as alpha), we
inline recursion for this case.
Create a new malloc type for the witness code and retire from using
the M_DEV type. The new type is called M_WITNESS and is only declared
if WITNESS is enabled.
Begin cleaning up some machdep/mutex.h code - specifically updated the
"optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN
and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently
need those.
Finally, caught up to the interface changes in all sys code.
Contributors: jake, jhb, jasone (in no particular order)
going to hurt sio(4) performance for the time being. As we get closer to
release and have more of the kernel unlocked we can come back to doing
arcane optimizations to workaround the limitations of the sio hardware.
