Impact: update documentation / help text
Original link is dead.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
As it is, all instances of ->release() for files that have ->fasync()
need to remember to evict file from fasync lists; forgetting that
creates a hole and we actually have a bunch that *does* forget.
So let's keep our lives simple - let __fput() check FASYNC in
file->f_flags and call ->fasync() there if it's been set. And lose that
crap in ->release() instances - leaving it there is still valid, but we
don't have to bother anymore.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On x86 systems with CONFIG_HPET_TIMER enabled, when
the HPET driver (drivers/char/hpet.c) is loaded,
an incorrect busy message is printed when the driver
initializes since the HPET has already been allocated
by the core timer code. Remove the warning message.
Signed-off-by: David John <davidjon@xenontk.org>
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
fix:
On Thursday 31 July 2008, Ingo Molnar wrote:
> drivers/built-in.o: In function `hpet_alloc':
> : undefined reference to `__udivdi3'
> drivers/built-in.o: In function `hpet_alloc':
> : undefined reference to `__umoddi3'
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Minor /dev/hpet updates and bugfixes:
* Remove dead code, mostly remnants of an incomplete/unusable
kernel interface ... noted when addressing "sparse" warnings:
+ hpet_unregister() and a routine it calls
+ hpet_task and all references, including hpet_task_lock
+ hpet_data.hd_flags (and HPET_DATA_PLATFORM)
* Correct and improve boot message:
+ displays *counter* (shared between comparators) bit width,
not *timer* bit widths (which are often mixed)
+ relabel "timers" as "comparators"; this is less confusing,
they are not independent like normal timers are (sigh)
+ display MHz not Hz; it's never less than 10 MHz.
* Tighten and correct the userspace interface code
+ don't accidentally program comparators in 64-bit mode using
32-bit values ... always force comparators into 32-bit mode
+ provide the correct bit definition flagging comparators with
periodic capability ... the ABI is unchanged
* Update Documentation/hpet.txt
+ be more correct and current
+ expand description a bit
+ don't mention that now-gone kernel interface
Plus, add a FIXME comment for something that could cause big trouble
on systems with more capable HPETs than at least Intel seems to ship.
It seems that few folk use this userspace interface; it's not very
usable given the general lack of HPET IRQ routing. I'm told that
the only real point of it any more is to mmap for fast timestamps;
IMO that's handled better through the gettimeofday() vsyscall.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch #if 0's the unused hpet_unregister().
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
HPET timer's IRQ is 0 by default. So we have to select which irq
will be used by these timers. We wait to set the timer's irq until
we really open it in order to reduce the chance of conflicting with
other device.
Signed-off-by: Kevin Hao <kexin.hao@windriver.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The commits:
commit 37a47db8d7
Author: Balaji Rao <balajirrao@gmail.com>
Date: Wed Jan 30 13:30:03 2008 +0100
x86: assign IRQs to HPET timers, fix
and
commit e3f37a54f6
Author: Balaji Rao <balajirrao@gmail.com>
Date: Wed Jan 30 13:30:03 2008 +0100
x86: assign IRQs to HPET timers
have been identified to cause a regression on some platforms due to
the assignement of legacy IRQs which makes the legacy devices
connected to those IRQs disfunctional.
Revert them.
This fixes http://bugzilla.kernel.org/show_bug.cgi?id=10382
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Looks like IRQ 31 is assigned to timer 3, even without the patch!
I wonder who wrote the number 31. But the manual says that it is
zero by default.
I think we should check whether the timer has been allocated an IRQ before
proceeding to assign one to it. Here is a patch that does this.
Signed-off-by: Balaji Rao <balajirrao@gmail.com>
Tested-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The userspace API for the HPET (see Documentation/hpet.txt) did not work. The
HPET_IE_ON ioctl was failing as there was no IRQ assigned to the timer
device. This patch fixes it by allocating IRQs to timer blocks in the HPET.
arch/x86/kernel/hpet.c | 13 +++++--------
drivers/char/hpet.c | 45 ++++++++++++++++++++++++++++++++++++++-------
include/linux/hpet.h | 2 +-
3 files changed, 44 insertions(+), 16 deletions(-)
Signed-off-by: Balaji Rao <balajirrao@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Following patch silents;
...
drivers/char/hpet.c:72: warning: 'clocksource_hpet' defined but not used
drivers/char/hpet.c:81: warning: 'hpet_clocksource' defined but not used
...
build warnings on i386, they appeared after commit 3b2b64fd31
Signed-off-by: S.Çağlar Onur <caglar@pardus.org.tr>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
--
drivers/char/hpet.c | 3 +++
1 files changed, 3 insertions(+), 0 deletions(-)
If hpet has been initialized before registering hpet driver, the callback
function of hpet_resources will return the status code of -EBUSY, which is
not defined in the ACPI exception table. So when ACPI checks the status
code of callback function, it will report the unknown exception code.
So the status code in ACPI is used instead of the generic error code in the
ACPI callback function of hpet_resources.
For example: -EBUSY is replaced by AE_ALREADY_EXISTS
-EINVAL is replaced by AE_NO_MEMORY
http://bugzilla.kernel.org/show_bug.cgi?id=8630
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
The HPET clocksource in drivers/char/hpet.c was written as generic code
for ia64, but it is not yet ready to replace the native HPET clocksource
implementations that the i386/x86-64 architectures use.
On x86[-64], trying to register this clocksource results in potentially
multiple hpet-based clocksources being registered, and if the ia64 one
is chosen on x86_64 some users have experienced hangs.
Eventually all three architectures may end up using the same code, but
that is not the case right now.
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Paolo Ornati <ornati@fastwebnet.it>
Cc: Bob Picco <bob.picco@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
modpost is going to use these to create e.g. acpi:ACPI0001
in modules.alias.
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>
This is a merge of Peter Keilty's initial patch (which was
revived by Bob Picco) for this with Hidetoshi Seto's fixes
and scaling improvements.
Acked-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
The semantic effect of insert_at_head is that it would allow new registered
sysctl entries to override existing sysctl entries of the same name. Which is
pain for caching and the proc interface never implemented.
I have done an audit and discovered that none of the current users of
register_sysctl care as (excpet for directories) they do not register
duplicate sysctl entries.
So this patch simply removes the support for overriding existing entries in
the sys_sysctl interface since no one uses it or cares and it makes future
enhancments harder.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: David Howells <dhowells@redhat.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Corey Minyard <minyard@acm.org>
Cc: Neil Brown <neilb@suse.de>
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Jan Kara <jack@ucw.cz>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Cc: David Chinner <dgc@sgi.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Patrick McHardy <kaber@trash.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In the binary sysctl interface the hpet driver was claiming to be the cdrom
driver. This is a no-no so remove support for the binary interface.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
Mark the static struct file_operations in drivers/char as const. Making
them const prevents accidental bugs, and moves them to the .rodata section
so that they no longer do any false sharing; in addition with the proper
debug option they are then protected against corruption..
[akpm@osdl.org: build fix]
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
ACPI address space descriptors contain _MIN, _MAX, and _LEN. _MIN and _MAX
are the bounds within which the region can be moved (this is clarified in
Table 6-38 of the ACPI 3.0 spec). We should use _LEN to determine the size
of the region, not _MAX - _MIN + 1.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Len Brown <len.brown@intel.com>
When the _CRS for a single HPET contains multiple EXTENDED_IRQ resources,
we overwrote hdp->hd_nirqs every time we found one.
So the driver worked when all the IRQs were described in a single
EXTENDED_IRQ resource, but failed when multiple resources were used.
(Strictly speaking, I think the latter is actually more correct, but both
styles have been used.)
Someday we should remove all the ACPI stuff from hpet.c and use PNP driver
registration instead. But currently PNP_MAX_IRQ is 2, and HPETs often have
more IRQs. Hint, hint, Adam :-)
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Acked-by: Bob Picco <robert.picco@hp.com>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Adam Belay <ambx1@neo.rr.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Completed a major overhaul of the Resource Manager code -
specifically, optimizations in the area of the AML/internal
resource conversion code. The code has been optimized to
simplify and eliminate duplicated code, CPU stack use has
been decreased by optimizing function parameters and local
variables, and naming conventions across the manager have
been standardized for clarity and ease of maintenance (this
includes function, parameter, variable, and struct/typedef
names.)
All Resource Manager dispatch and information tables have
been moved to a single location for clarity and ease of
maintenance. One new file was created, named "rsinfo.c".
The ACPI return macros (return_ACPI_STATUS, etc.) have
been modified to guarantee that the argument is
not evaluated twice, making them less prone to macro
side-effects. However, since there exists the possibility
of additional stack use if a particular compiler cannot
optimize them (such as in the debug generation case),
the original macros are optionally available. Note that
some invocations of the return_VALUE macro may now cause
size mismatch warnings; the return_UINT8 and return_UINT32
macros are provided to eliminate these. (From Randy Dunlap)
Implemented a new mechanism to enable debug tracing for
individual control methods. A new external interface,
acpi_debug_trace(), is provided to enable this mechanism. The
intent is to allow the host OS to easily enable and disable
tracing for problematic control methods. This interface
can be easily exposed to a user or debugger interface if
desired. See the file psxface.c for details.
acpi_ut_callocate() will now return a valid pointer if a
length of zero is specified - a length of one is used
and a warning is issued. This matches the behavior of
acpi_ut_allocate().
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
- Use kzalloc() instead of kmalloc + memset.
- Clean/fix some printk's.
- Use NULL for pointers instead of 0.
- Combine hpet busy searching locations into a function call.
Signed-off-by: Randy Dunlap <randy_d_dunlap@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- Use HPET physical address to detect duplicates, not logical addresses.
Using logical (mapped) addresses fails to detect duplicates
because ioremap() returns a new mapped address each time.
- iounmap() regions when duplicate/busy areas are found.
Signed-off-by: Randy Dunlap <randy_d_dunlap@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Allow the ACPI HPET description table to use a resource type of FIXED_MEM32
for the HPET reource. Use the fixed resoure size of 1 KB for the HPET
resource as per the HPET spec.
Signed-off-by: Randy Dunlap <randy_d_dunlap@linux.intel.com>
Acked-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When booting, display the timer frequency in Hertz instead of as tick length
in nanoseconds. Apart from saving a local variable, this makes the message
more easily comprehensible.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Cc: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
In the hpet_ioctl_common() function, devp->hd_hpets is already cached in the
hpetp variable, so we can use just that.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Cc: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix two instances where a function would access the first HPET device instead
of the current one.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Cc: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Clear the ht_opaque field in the hpet_register() function before searching for
a free timer to prevent the function from incorrectly assuming that the search
succeeded afterwards.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Cc: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix a division by zero that happened when the HPET_INFO ioctl was called
before a timer frequency had been set.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Cc: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix a wrong memory access in hpet_ioctl_common(). It was not possible to use
the HPET_INFO ioctl from kernel space because it always called copy_to_user().
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Cc: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds support for shared HPET interrupts.
The driver previously acknowledged interrupts for both edge and level
interrupts, but didn't actually allow a shared interrupt in the latter case.
We use a new per-timer flag to save whether the timer's interrupt might be
shared, and use it to do the processing required for level interrupts only if
necessary.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Acked-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
It was only the RTC hardware that restricted interrupt frequencies to a power
of two. There is no reason to take over this restriction into the HPET
driver, so remove the offending check.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Acked-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch removes several reads of a timer's config register that serve no
purpose whatsoever.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Acked-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The variable hpet_ntimer is never read, so remove it.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Acked-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
On 32-bit architectures, the multiplication in the argument for
hpet_time_div() often overflows. In the typical case of a 14.32 MHz timer,
this happens when the desired frequency exceeds 61 Hz.
To avoid this multiplication, we can precompute and store the hardware
timer frequency, instead of the period, in the device structure, which
leaves us with a simple division when computing the number of timer ticks.
As a side effect, this also removes a theoretical bug where the timer
interpolator's frequency would be computed as a 32-bit value even if the
HPET frequency is greater than 2^32 Hz (the HPET spec allows up to 10 GHz).
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Disallow setting an interrupt frequency of zero (which would result in a
division by zero), and disallow enabling the interrupt when the frequency
hasn't yet been set (which would use an interrupt period of zero).
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The address passed to io_remap_pfn_range() in hpet_mmap() does not need to
be converted using __pa(): it is already a physical address. This bug was
found and the patch suggested by Clay Harris.
I introduced this particular bug when making io_remap_pfn_range changes a
few months ago. In fact mmap()ing /dev/hpet has *never* previously worked:
before my changes __pa() was being executed on an ioremap()ed virtual
address, which is also invalid.
Signed-off-by: Keir Fraser <keir@xensource.com>
Cc: Robert Picco <Robert.Picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>