Commit Graph

27 Commits

Author SHA1 Message Date
avg
db453a7a34 add support for console resuming, implement it for uart, use on x86
This change adds a new optional console method cn_resume and a kernel
console interface cnresume.  Consoles that may need to re-initialize
their hardware after suspend (e.g., because firmware does not care to do
it) will implement cn_resume.  Note that it is called in rather early
environment not unlike early boot, so the same restrictions apply.
Platform specific code, for platforms that support hardware suspend,
should call cnresume early after resume, before any console output is
expected.

This change fixes a problem with a system of mine failing to resume when
a serial console is used.  I found that the serial port was in a strange
configuration and an attempt to write to it likely resulted in an
infinite loop.

To avoid adding cn_resume method to every console driver, CONSOLE_DRIVER
macro has been extended to support optional methods.

Reviewed by:	imp, mav
MFC after:	3 weeks
Differential Revision: https://reviews.freebsd.org/D15552
2018-05-29 16:16:24 +00:00
pfg
4736ccfd9c sys: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
2017-11-20 19:43:44 +00:00
emaste
00b67b15b9 Renumber license clauses in sys/kern to avoid skipping #3 2016-09-15 13:16:20 +00:00
jkim
318c4f97e6 CALLOUT_MPSAFE has lost its meaning since r141428, i.e., for more than ten
years for head.  However, it is continuously misused as the mpsafe argument
for callout_init(9).  Deprecate the flag and clean up callout_init() calls
to make them more consistent.

Differential Revision:	https://reviews.freebsd.org/D2613
Reviewed by:	jhb
MFC after:	2 weeks
2015-05-22 17:05:21 +00:00
ian
cb2eadc65f Include the nulterm byte in the sysctl string.
PR:		195668
2015-03-15 00:36:08 +00:00
hselasky
dd66ca979a Rework r276532 a bit. Always avoid recursing into the console drivers
clients, hence they might not handle it very well. This change allows
debugging mutex problems with kernel console drivers when
"debug.witness.skipspin=0" is set in the boot environment.

MFC after:	1 week
2015-01-03 17:21:19 +00:00
hselasky
c81bb57ba0 The "cnputs_mtx" mutex must be allowed to recurse. Debug prints and/or
witness printouts in the console driver clients can cause this mutex
to recurse by calls to "printf()" from witness for example. In
particular this can happen if "debug.witness.skipspin=0" is set in the
boot environment.

MFC after:	1 week
2015-01-02 13:10:33 +00:00
zbb
aee9f2a5a3 Stop using early_putc immediately after configuring console with cninit()
Early UART should be released right after system console initialization is
completed. Otherwise, after cninit() both early and system console coexist
what may lead to various issues (i.a. writing to unmapped early
UART address). This cannot be done in cninit_finish() since it can be
called late at the end of MI configuration.

Obtained from:   Semihalf
Reviewed by:     andrew
Sponsored by:    The FreeBSD Foundation
2014-11-19 14:23:29 +00:00
dumbbell
5f06d19789 Enable vt(4) by default
vt(4) is a new console driver which brings features such as:
    o  Support for Unicode and double-width characters
    o  Integration with the KMS kernel video drivers
    o  Support for UEFI

You may need to update your console settings in /etc/rc.conf, most
probably the keymap. During boot, /etc/rc.d/syscons will indicate what
you need to do.

vt(4) still has issues and lacks some features compared to syscons(4).
See the wiki for up-to-date information:
    https://wiki.freebsd.org/Newcons

If you want to keep using syscons(4), you can do so by adding the
following line to /boot/loader.conf:
    kern.vty=sc

Differential Revision:	https://reviews.freebsd.org/D1005
Discussed with:	emaste@, nwhitehorn@, ray@
Relnotes:	yes
2014-11-04 10:18:03 +00:00
jhb
d08fb7f877 Convert from timeout(9) to callout(9). 2014-09-22 14:27:26 +00:00
emaste
833365590a Fix typos in VTY constant names from r268158 2014-07-02 14:47:48 +00:00
emaste
9825a4c806 Prefer vt(4) for UEFI boot
The UEFI framebuffer driver vt_efifb requires vt(4), so add a mechanism
for the startup routine to set the preferred console.  This change is
ugly because console init happens very early in the boot, making a
cleaner interface difficult.  This change is intended only to facilitate
the sc(4) / vt(4) transition, and can be reverted once vt(4) is the
default.
2014-07-02 13:24:21 +00:00
hselasky
35b126e324 Pull in r267961 and r267973 again. Fix for issues reported will follow. 2014-06-28 03:56:17 +00:00
gjb
fc21f40567 Revert r267961, r267973:
These changes prevent sysctl(8) from returning proper output,
such as:

 1) no output from sysctl(8)
 2) erroneously returning ENOMEM with tools like truss(1)
    or uname(1)
 truss: can not get etype: Cannot allocate memory
2014-06-27 22:05:21 +00:00
emaste
75aefa2c4a Add CTLFLAG_NOFETCH flag; console vty code runs before tunable fetch
Also remove redundant "" assignment for string in BSS.

Submitted by:	hselasky@
2014-06-27 19:07:35 +00:00
emaste
2b75e7bbda Use a common tunable to choose between vt(4)/sc(4)
With this change and previous work from ray@ it will be possible to put
both in GENERIC, and have one enabled by default, but allow the other to
be selected via the loader.

(The previous implementation had separate kern.vt.disable and
hw.syscons.disable tunables, and would panic if both drivers were
compiled in and neither was explicitly disabled.)

MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
2014-06-27 17:50:33 +00:00
ian
4ca4e5e369 Rework the EARLY_PRINTF mechanism. Instead of defining a special eprintf()
routine, now a platform can provide a pointer to an early_putc() routine
which is used instead of cn_putc().  Control can be handed off from early
printf support to standard console support by NULLing out the pointer
during standard console init.

This leverages all the existing error reporting that uses printf calls,
such as panic() which can now be usefully employed even in early
platform init code (useful at least to those who maintain that code and
build kernels with EARLY_PRINTF defined).

Reviewed by:	imp, eadler
2014-02-12 00:53:38 +00:00
imp
8b02060930 Delete echoed doesn't rub out the previous character, so always
use <backspace> <space> <backspace> instead. This fixes hitting
DELETE instead of BACKSPACE at mountroot> prompt.
2013-12-31 04:40:25 +00:00
avg
7e3795ec58 cngetc: use cpu_spinwait to ease the cncheckc loop a tiny bit
Reviewed by:	julian
MFC after:	10 days
2012-10-06 19:50:23 +00:00
avg
34b585c853 belatedly transfer copyrights from libkern/gets.c to kern_cons.c
MFC after:	2 months
MFC with:	r228642
2011-12-17 15:50:45 +00:00
avg
53f09b7daf introduce cngets, a method for kernel to read a string from console
This is intended as a replacement for libkern's gets and mostly borrows
its implementation.  It uses cngrab/cnungrab to delimit kernel's access
to console input.

Note: libkern's gets obviously doesn't share any bits of implementation
iwth libc's gets.  They also have different APIs and the former doesn't
have the overflow problems of the latter.

Inspired by:	bde
MFC after:	2 months
2011-12-17 15:16:54 +00:00
avg
d062f5e7d8 introduce cngrab/cnungrab stub calls in some places where they make sense
MFC after:	2 months
2011-12-17 15:11:22 +00:00
avg
f6def40e18 kern cons: introduce infrastructure for console grabbing by kernel
At the moment grab and ungrab methods of all console drivers are no-ops.

Current intended meaning of the calls is that the kernel takes control of
console input.  In the future the semantics may be extended to mean that
the calling thread takes full ownership of the console (e.g. console
output from other threads could be suspended).

Inspired by:	bde
MFC after:	2 months
2011-12-17 15:08:43 +00:00
gavin
dbc7cd5ae9 Add descriptions to a handful of sysctl nodes.
PR:		kern/148580
Submitted by:	Galimov Albert <wtfcrap mail.ru>
MFC after:	1 week
2010-08-09 14:48:31 +00:00
ed
7669d1f2c1 Allow multiple console devices per driver without insane code duplication.
Say, a driver wants to have multiple console devices to pick from, you
would normally write down something like this:

	CONSOLE_DRIVER(dev1);
	CONSOLE_DRIVER(dev2);

Unfortunately, this means that you have to declare 10 cn routines,
instead of 5. It also isn't possible to initialize cn_arg on beforehand.

I noticed this restriction when I was implementing some of the console
bits for my vt(4) driver in my newcons branch. I have a single set of cn
routines (termcn_*) which are shared by all vt(4) console devices.

In order to solve this, I'm adding a separate consdev_ops structure,
which contains all the function pointers. This structure is referenced
through consdev's cn_ops field.

While there, I'm removing CONS_DRIVER() and cn_checkc, which have been
deprecated for years. They weren't used throughout the source, until the
Xen console driver showed up. CONSOLE_DRIVER() has been changed to do
the right thing. It now declares both the consdev and consdev_ops
structure and ties them together. In other words: this change doesn't
change the KPI for drivers that used the regular way of declaring
console devices.

If drivers want to use multiple console devices, they can do this as
follows:

	static const struct consdev_ops mydriver_cnops = {
		.cn_probe	= mydriver_cnprobe,
		...
	};
	static struct mydriver_softc cons0_softc = {
		...
	};
	CONSOLE_DEVICE(cons0, mydriver_cnops, &cons0_softc);
	static struct mydriver_softc cons1_softc = {
		...
	};
	CONSOLE_DEVICE(cons1, mydriver_cnops, &cons1_softc);

Obtained from:	//depot/user/ed/newcons/...
2009-08-24 10:53:30 +00:00
ed
f854be19d0 Remove unneeded variable `ocn_mute'.
Found by:	LLVM's scan-build
2009-02-26 13:01:45 +00:00
ed
c2c324d379 Reimplement the /dev/console device node.
One of the pieces of code that I had left alone during the development
of the MPSAFE TTY layer, was tty_cons.c. This file actually has two
different functions:

- It contains low-level console input/output routines (cnputc(), etc).

- It creates /dev/console and wraps all its cdevsw calls to the
  appropriate TTY.

This commit reimplements the second set of functions by moving it
directly into the TTY layer. /dev/console is now a character device node
that's basically a regular TTY, but does a lookup of `si_drv1' each time
you open it. d_write has also been changed to call log_console().
d_close() is not present, because we must make sure we don't revoke the
TTY after writing a log message to it.

Even though I'm not convinced this is in line with the future directions
of our console code, it is a good move for now. It removes recursive
locking from the top half of the TTY layer. The previous implementation
called into the TTY layer with Giant held.

I'm renaming tty_cons.c to kern_cons.c now. The code hardly contains any
TTY related bits, so we'd better give it a less misleading name.

Tested by:	Andrzej Tobola <ato iem pw edu pl>,
		Carlos A.M. dos Santos <unixmania gmail com>,
		Eygene Ryabinkin <rea-fbsd codelabs ru>
2008-11-01 08:35:28 +00:00