ATM pthread_cond_signal is unnecessarily slow, because it wakes one waiter
(which at least on UP usually means an immediate context switch to one of
the waiter threads). This waiter wakes up and after a few instructions it
attempts to acquire the cv internal lock, but that lock is still held by
the thread calling pthread_cond_signal. So it goes to sleep and eventually
the signalling thread is scheduled in, unlocks the internal lock and wakes
the waiter again.
Now, before 2003-09-21 NPTL was using FUTEX_REQUEUE in pthread_cond_signal
to avoid this performance issue, but it was removed when locks were
redesigned to the 3 state scheme (unlocked, locked uncontended, locked
contended).
Following scenario shows why simply using FUTEX_REQUEUE in
pthread_cond_signal together with using lll_mutex_unlock_force in place of
lll_mutex_unlock is not enough and probably why it has been disabled at
that time:
The number is value in cv->__data.__lock.
thr1 thr2 thr3
0 pthread_cond_wait
1 lll_mutex_lock (cv->__data.__lock)
0 lll_mutex_unlock (cv->__data.__lock)
0 lll_futex_wait (&cv->__data.__futex, futexval)
0 pthread_cond_signal
1 lll_mutex_lock (cv->__data.__lock)
1 pthread_cond_signal
2 lll_mutex_lock (cv->__data.__lock)
2 lll_futex_wait (&cv->__data.__lock, 2)
2 lll_futex_requeue (&cv->__data.__futex, 0, 1, &cv->__data.__lock)
# FUTEX_REQUEUE, not FUTEX_CMP_REQUEUE
2 lll_mutex_unlock_force (cv->__data.__lock)
0 cv->__data.__lock = 0
0 lll_futex_wake (&cv->__data.__lock, 1)
1 lll_mutex_lock (cv->__data.__lock)
0 lll_mutex_unlock (cv->__data.__lock)
# Here, lll_mutex_unlock doesn't know there are threads waiting
# on the internal cv's lock
Now, I believe it is possible to use FUTEX_REQUEUE in pthread_cond_signal,
but it will cost us not one, but 2 extra syscalls and, what's worse, one of
these extra syscalls will be done for every single waiting loop in
pthread_cond_*wait.
We would need to use lll_mutex_unlock_force in pthread_cond_signal after
requeue and lll_mutex_cond_lock in pthread_cond_*wait after lll_futex_wait.
Another alternative is to do the unlocking pthread_cond_signal needs to do
(the lock can't be unlocked before lll_futex_wake, as that is racy) in the
kernel.
I have implemented both variants, futex-requeue-glibc.patch is the first
one and futex-wake_op{,-glibc}.patch is the unlocking inside of the kernel.
The kernel interface allows userland to specify how exactly an unlocking
operation should look like (some atomic arithmetic operation with optional
constant argument and comparison of the previous futex value with another
constant).
It has been implemented just for ppc*, x86_64 and i?86, for other
architectures I'm including just a stub header which can be used as a
starting point by maintainers to write support for their arches and ATM
will just return -ENOSYS for FUTEX_WAKE_OP. The requeue patch has been
(lightly) tested just on x86_64, the wake_op patch on ppc64 kernel running
32-bit and 64-bit NPTL and x86_64 kernel running 32-bit and 64-bit NPTL.
With the following benchmark on UP x86-64 I get:
for i in nptl-orig nptl-requeue nptl-wake_op; do echo time elf/ld.so --library-path .:$i /tmp/bench; \
for j in 1 2; do echo ( time elf/ld.so --library-path .:$i /tmp/bench ) 2>&1; done; done
time elf/ld.so --library-path .:nptl-orig /tmp/bench
real 0m0.655s user 0m0.253s sys 0m0.403s
real 0m0.657s user 0m0.269s sys 0m0.388s
time elf/ld.so --library-path .:nptl-requeue /tmp/bench
real 0m0.496s user 0m0.225s sys 0m0.271s
real 0m0.531s user 0m0.242s sys 0m0.288s
time elf/ld.so --library-path .:nptl-wake_op /tmp/bench
real 0m0.380s user 0m0.176s sys 0m0.204s
real 0m0.382s user 0m0.175s sys 0m0.207s
The benchmark is at:
http://sourceware.org/ml/libc-alpha/2005-03/txt00001.txt
Older futex-requeue-glibc.patch version is at:
http://sourceware.org/ml/libc-alpha/2005-03/txt00002.txt
Older futex-wake_op-glibc.patch version is at:
http://sourceware.org/ml/libc-alpha/2005-03/txt00003.txt
Will post a new version (just x86-64 fixes so that the patch
applies against pthread_cond_signal.S) to libc-hacker ml soon.
Attached is the kernel FUTEX_WAKE_OP patch as well as a simple-minded
testcase that will not test the atomicity of the operation, but at least
check if the threads that should have been woken up are woken up and
whether the arithmetic operation in the kernel gave the expected results.
Acked-by: Ingo Molnar <mingo@redhat.com>
Cc: Ulrich Drepper <drepper@redhat.com>
Cc: Jamie Lokier <jamie@shareable.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Patch from Tony Lindgren
This patch syncs the mainline kernel with linux-omap tree.
The highlights of the patch are:
- Start adding 24xx support by Paul Mundt
- Clean-up of cpu detection by Dirk Behme and Tony Lindgren
- Add DSP header by Toshihiro Kobayashi
- Add support for mtd-xip by Vladimir Barinov
- Add various new mux registers
- Move OMAP specific serial defines back to serial.h
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Ben Dooks
Add the Simtec Anubis to the list of supported
machines in the arch/arm/mach-s3c2410 directory.
This ensures the core peripherals are registered,
the timer source is configured and the correct
power-management is enabled.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Richard Purdie
This patch updates the PCMCIA pxa2xx_sharpsl driver to support multiple scoop
devices by adding a scoop to pcmcia slot mapping structure. It adds platform
support for poodle, is known to work on spitz (which is dual slot) and
should also support collie with a minor amount of further work.
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This is used only in slab.c and each architecture gets to define whcih
underlying type is to be used.
Seems a bit silly - move it to slab.c and use the same type for all
architectures: unsigned int.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Someone mentioned that almost all the architectures used basically the same
implementation of get_order. This patch consolidates them into
asm-generic/page.h and includes that in the appropriate places. The
exceptions are ia64 and ppc which have their own (presumably optimised)
versions.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is part of Thomas Gleixner's generic IRQ patch, which converts
ARM to use the generic IRQ subsystem. Here, we wrap calls to
desc->handler() in an inline function, desc_handle_irq(). This
reduces the size of Thomas' patch since the changes become more
localised.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This is part of Thomas Gleixner's generic IRQ patch, which converts
ARM to use the generic IRQ subsystem. Here, we rename two of the
irq_chip methods - wake becomes set_wake, and type becomes set_type.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Nicolas Pitre
The prototype for sys_fadvise64_64() is:
long sys_fadvise64_64(int fd, loff_t offset, loff_t len, int advice)
The argument list is therefore as follows on legacy ABI:
fd: type int (r0)
offset: type long long (r1-r2)
len: type long long (r3-sp[0])
advice: type int (sp[4])
With EABI this becomes:
fd: type int (r0)
offset: type long long (r2-r3)
len: type long long (sp[0]-sp[4])
advice: type int (sp[8])
Not only do we have ABI differences here, but the EABI version requires
one additional word on the syscall stack.
To avoid the ABI mismatch and the extra stack space required with EABI
this syscall is now defined with a different argument ordering
on ARM as follows:
long sys_arm_fadvise64_64(int fd, int advice, loff_t offset, loff_t len)
This gives us the following ABI independent argument distribution:
fd: type int (r0)
advice: type int (r1)
offset: type long long (r2-r3)
len: type long long (sp[0]-sp[4])
Now, since the syscall entry code takes care of 5 registers only by
default including the store of r4 to the stack, we need a wrapper to
store r5 to the stack as well. Because that wrapper was missing and was
always required this means that sys_fadvise64_64 never worked on ARM and
therefore we can safely reuse its syscall number for our new
sys_arm_fadvise64_64 interface.
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from David Vrabel
Correct the ioread* and iowrite* functions. In particular, add an offset to the cookie in ioport_map so we can map I/O port ranges starting from 0 (0 is for reporting errors).
Signed-off-by: David Vrabel <dvrabel@arcom.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Richard Purdie
Add some extra pxa27x register definitions needed for the Sharp
SL-C3000 (Spitz).
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Nicolas Pitre
There is no need to define __ARCH_WANT_SYS_FADVISE64 on ARM since it
only serves to compile in a compatibility wrapper for sys_fadvise64
which never was tied to any syscall number.
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Ben Dooks
Add the definitions for the S3C2410_CLKSLOW registers to
the header files, and show the values when the system
starts up
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Deepak Saxena
This patch implements the set_irq_type() hooks for configuring GPIO
IRQ type and updates all the platforms to use it instead of the
gpio_line_config() function which is now used to configure input
vs. output on the pins.
Signed-off-by: Deepak Saxena <dsaxena@plexity.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
As pointed out in the following thread, the CLOCK_TICK_RATE setting for
IXP4xx is incorrect b/c the HW ignores the lowest 2 bits of the LATCH
value.
http://lists.arm.linux.org.uk/pipermail/linux-arm-kernel/2005-August/030950.html
Tnx to George Anziger and Egil Hjelmeland for finding the issue.
Signed-off-by: Deepak Saxena <dsaxena@plexity.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
a bunch of functions switched from volatile to __attribute__((noreturn)) and
from const to __attribute_pure__
Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add platform device data for the SA11x0 MCP device. This allows
platforms to customise the configuration of the SA11x0 MCP device
according to their needs.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Ben Dooks
Rename the s3c2410_report_oc() to s3c2410_usb_report_oc()
as this is an usb specific function.
Change port power on the usb-simtec implementation to only
power up the output if both are set, as per the usb 1.1
specification
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Unfortunately, we can't use the "user" bit in the page tables to
control whether a page table entry is "global" or "asid" specific,
since the vector page is mapped as "user" accessible but is not
process specific.
Therefore, give direct control of the ARMv6 "nG" (not global)
bit to the mm layers.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
In yenta_socket, we default to using the resource setting of the CardBus
bridge. However, this is a PCI-bus-centric view of resources and thus needs
to be converted to generic resources first. Therefore, add a call to
pcibios_bus_to_resource() call in between. This function is a mere wrapper on
x86 and friends, however on some others it already exists, is added in this
patch (alpha, arm, ppc, ppc64) or still needs to be provided (parisc -- where
is its pcibios_resource_to_bus() ?).
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We sometimes forgot to check whether the exclusive store succeeded.
Ensure that we always check. Also ensure that we always use the
out of line versions, since the inline versions are not SMP safe.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
When the kernel is working well and we want to restart cleanly
kernel_restart is the function to use. But in many instances
the kernel wants to reboot when thing are expected to be working
very badly such as from panic or a software watchdog handler.
This patch adds the function emergency_restart() so that
callers can be clear what semantics they expect when calling
restart. emergency_restart() is expected to be callable
from interrupt context and possibly reliable in even more
trying circumstances.
This is an initial generic implementation for all architectures.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Convert explicit gcc asm-based memory barriers into smp_mb() calls.
These change between barrier() and the ARMv6 data memory barrier
instruction depending on whether ARMv6 SMP is enabled.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Dimitry Andric
- Change S3C2440_IISCON_MPLL to S3C2440_IISMOD_MPLL:
The S3C2440 IISCON register doesn\'t control the master clock selection, this is done with the IISMOD register.
- Correct S3C2410_IISMOD_256FS and S3C2410_IISMOD_384FS:
This is set via bit 2 of IISMOD, not bit 1.
- Add S3C2410_IISCON_PSCEN (prescaler enable), for completeness\' sake.
Signed-off-by: Dimitry Andric <dimitry.andric@tomtom.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Sascha Hauer
The dmacr needs different settings on some boards. This patch makes the
register configurable by the platform part.
Also we have imxfb_disable_controller(), so lets use it.
Signed-off-by: Steven Scholz
Signed-off-by: Sascha Hauer
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Alexander Schulz
This patch brings a new default config file for the shark and
fixes a compilation issue with io addressing and a runtime
problem with the serial ports, where I corrected a wrong
regshift value.
These are all shark specific files so I hope it is ok to
put them in one patch.
Signed-off-by: Alexander Schulz <alex@shark-linux.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
http://bugme.osdl.org/show_bug.cgi?id=4016
Written-by: David Shaohua Li <shaohua.li@intel.com>
Acked-by: Adam Belay <abelay@novell.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Patch from Tony Lindgren
This patch by various OMAP developers syncs the OMAP
specific arch files with the linux-omap tree.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Tony Lindgren
This patch by various OMAP developers syncs the OMAP
specific arch files with the linux-omap tree.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Tony Lindgren
This patch by various OMAP developers syncs the OMAP
specific include files with the linux-omap tree.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Lennert Buytenhek
This patch converts the ixp2000 serial port over to a platform
serial device.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Deepak Saxena <dsaxena@plexity.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Deepak Saxena
This patch implements the iomap API for Intel IXP4xx NPU systems.
We need to implement our own version of the API functions b/c of the
PCI hostbridge does not provide the capability to map PCI I/O space
into the CPU's physical memory space. In addition, if a system has
more than 64M of PCI memory mapped BARs, PCI memory must also be
accessed indirectly. This patch changes the assignment of PCI I/O
resources to fall into to 0x0000:0xffff range so that we can trap
I/O areas in our ioread/iowrite macros.
Signed-off-by: Deepak Saxena
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add __attribute__((packed)) to ensure that the stat64 structure is
correctly laid out no matter which ABI the kernel is compiled for.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Todd Poynor
Add definition of K0DB4 SDCLK<0,3> divide-by-4 control/status bit in the
MDREFR register for Intel XScale PXA27x.
Signed-off-by: Todd Poynor <tpoynor@mvista.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Todd Poynor
Add support for PXA27x Standby mode, a low-power mode that retains CPU
and some peripheral state (the existing "sleep" mode is a power-power
mode that retains less state). Activated via:
echo -n standby > /sys/power/state
From: David Burrage and Todd Poynor
Signed-off-by: Todd Poynor <tpoynor@mvista.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
If we receive an unrecognised abort during boot, don't try to
send a signal to pid0, but instead report the current state.
This leads to less confusing debug reports.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Richard Purdie
With DEBUG enabled, head.S includes arch/debug-macro.S. On the PXA, this
contains references to the macro io_p2v() so hardware.h needs to be
included.
Signed-off-by: Richard Purdie <rpurdie@openedhand.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Convert ARMs timer implementations to use readl/writel instead of accessing
the registers via a struct.
People have recently asked if accessing timers via a structure is the
"right way" and its not the Linux way. So fix this code to conform to
"The Linux Way"(tm).
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Patch from Ben Dooks
This provides the s3c24xx audio platform data which can be
supplied from any of the board specific drivers.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The existing TLB flush implementations only have an effect on
the local CPU. Prefix them with local_.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
With CONFIG_PCI=n:
In file included from include/linux/pci.h:917,
from lib/iomap.c:6:
include/asm/pci.h:104: warning: `enum pci_dma_burst_strategy' declared inside parameter list
include/asm/pci.h:104: warning: its scope is only this definition or declaration, which is probably not what you want.
include/asm/pci.h: In function `pci_dma_burst_advice':
include/asm/pci.h:106: dereferencing pointer to incomplete type
include/asm/pci.h:106: `PCI_DMA_BURST_INFINITY' undeclared (first use in this function)
include/asm/pci.h:106: (Each undeclared identifier is reported only once
include/asm/pci.h:106: for each function it appears in.)
make[1]: *** [lib/iomap.o] Error 1
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
After seeing, at best, "guesses" as to the following kind
of information in several drivers, I decided that we really
need a way for platforms to specifically give advice in this
area for what works best with their PCI controller implementation.
Basically, this new interface gives DMA bursting advice on
PCI. There are three forms of the advice:
1) Burst as much as possible, it is not necessary to end bursts
on some particular boundary for best performance.
2) Burst on some byte count multiple. A DMA burst to some multiple of
number of bytes may be done, but it is important to end the burst
on an exact multiple for best performance.
The best example of this I am aware of are the PPC64 PCI
controllers, where if you end a burst mid-cacheline then
chip has to refetch the data and the IOMMU translations
which hurts performance a lot.
3) Burst on a single byte count multiple. Bursts shall end
exactly on the next multiple boundary for best performance.
Sparc64 and Alpha's PCI controllers operate this way. They
disconnect any device which tries to burst across a cacheline
boundary.
Actually, newer sparc64 PCI controllers do not have this behavior.
That is why the "pdev" is passed into the interface, so I can
add code later to check which PCI controller the system is using
and give advice accordingly.
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
More omap_udc updates:
* OMAP 1710 updates
- new UDC bit for clearing endpoint toggle, affecting CLEAR_HALT
- new OTG bits affecting wakeup
* Fix the bug Vladimir noted, that IN-DMA transfer code path kicks in
for under 1024 bytes (not "up to 1024 bytes")
* Handle transceiver setup more intelligently
- use transceiver whenever one's available; this can be handy
for GPIO based, loopback, or transceiverless configs
- cleanup correctly after the "unrecognized HMC" case
* DMA performance tweaks
- allow burst/pack for memory access
- use 16 bit DMA access most of the time on TIPB
* Add workarounds for some DMA errata (not observed "in the wild"):
- DMA CSAC/CDAC reads returning zero
- RX/TX DMA config registers bit 12 always reads as zero (TI patch)
* More "sparse" warnings removed, notably "changing" the SETUP packet
to return data in USB byteorder (an API change, null effect on OMAP
except for these warnings).
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Patch from Deepak Saxena
Accidently swapped the order of movne and orrne. Bad.
Signed-off-by: Deepak Saxena <dsaxena@plexity.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Michael Burian
This does not look like an include file for "i386", so use "ARM" instead.
Signed-off-by: Michael Burian <dynmail1@gassner-waagen.at>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This call allows the dynamic tick support to reprogram the timer
immediately before the CPU idles.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Lennert Buytenhek
Add a mapping for the ixp2400 and ixp2800 msf unit. The msf is the
ixp2000's 'media and switch fabric' unit, which handles the networking
part of the chip.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Deepak Saxena
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Lennert Buytenhek
Add a comment to asm/arch-ixp2000/ixp2000-regs.h describing the
ixp2000 virtual memory map layout.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Deepak Saxena
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Lennert Buytenhek
As the ixdp cpld mappings now live at 0xfe000000, we can push
VMALLOC_END upwards to 0xfb000000, where the first iotable mapping
begins.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Deepak Saxena
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Lennert Buytenhek
All ixdp platforms currently have a cpld mapped in at 0xfafff000.
Since this address is not 1M-aligned, a regular page mapping will be
used instead of a section mapping, which opens up the possibility of
triggering ixp2400 erratum #66 as we only do the XCB=101 workaround
thing for section mappings.
There is still a lot of space higher up in the virtual memory map
for 1M mappings, so move the cpld mapping to 0xfe000000 and make it
1M big so that a section mapping will be used for it.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Deepak Saxena
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Instead of requiring architecture code to interact with the scheduler's
locking implementation, provide a couple of defines that can be used by the
architecture to request runqueue unlocked context switches, and ask for
interrupts to be enabled over the context switch.
Also replaces the "switch_lock" used by these architectures with an oncpu
flag (note, not a potentially slow bitflag). This eliminates one bus
locked memory operation when context switching, and simplifies the
task_running function.
Signed-off-by: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds support for Dynamic Tick Timer for ARM. Dynamic Tick is
also known as VST (Variable Scheduling Timeouts).
Dynamic Tick has been in use in the OMAP tree since last October. The
patch is not intrusive, and does not do anything unless CONFIG_NO_IDLE_HZ
is defined. This patch has the following fixed based on comments from
RMK:
- Time is updated before calling interrupt handlers.
- Added new interrupt flag SA_TIMER to avoid duplicate timer interrupts
- Moved struct dyn_tick_timer to time.h until we at some point probably
have an arch independent dyn-tick.h
- Cleaned up testing for DYN_TICK_ENABLED in irq.c
I've cleaned up this patch to fix some remaining issues:
- Call the timer tick handler with irqs disabled, as it would be from
a normal interrupt
- if we have a dyn_tick, we better implement all methods.
- generic timer_dyn_reprogram() call, to be called before sleeping
- added command line option - "dyntick=" to allow boot-time control
of this feature
-- rmk
Signed-off-by: Tony Lindgren
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Lennert Buytenhek
The later ixp2000 models don't need the PCI I/O workaround that we
currently perform. Add a config option to disable the workaround,
and panic on boot if a kernel without the workaround is booted on a
buggy chip. As only pre-production ixp2000s need the workaround,
the default is for it not to be configured in.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Deepak Saxena
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Lennert Buytenhek
A number of ixp2000 models have a bug where the byte lanes for PCI I/O
transactions are swapped. We already work around this in our versions
of {in,out}{b,w,l}, but we also need to perform these workarounds in a
custom implementation of the new iomap API, provided in this patch.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Deepak Saxena
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Lennert Buytenhek
This patch conditionalises the io{read,write}{8,16,32} defines and the
prototypes for ioport_map/ioport_unmap in asm-arm/io.h on ioread8 not
already having been defined. This is done so that platforms can provide
their own implementation of the iomap API, ixp2000 for example needs
this.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Deepak Saxena
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Deepak Saxena
Current IXP4xx debug macros do not work in the small window between
the MMU being enabled and the call to map_io() b/c the standard
peripheral mapping is not properly setup for use with the low-level
debug code. This patch creates a new section-aligned mapping for the
UART specifically for use with the debug macros.
Signed-off-by: Deepak Saxena
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Lennert Buytenhek
This patch cleans up the ixp2000 gpio irq code and implements the
set_irq_type method for gpio irqs so that users can select for which
events (falling edge/rising edge/level low/level high) on the gpio
pin they want the corresponding gpio irq to be triggered.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Deepak Saxena
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Lennert Buytenhek
Two macros that are used on the ixp2000 to fixup byte lane enables
for I/O space accesses, align{b,w}, use their arguments without
parenthesizing them.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The preempt_count member of struct thread_info is currently either defined
as int, unsigned int or __s32 depending on arch. This patch makes the type
of preempt_count an int on all archs.
Having preempt_count be an unsigned type prevents the catching of
preempt_count < 0 bugs, and using int on some archs and __s32 on others is
not exactely "neat" - much nicer when it's just int all over.
A previous version of this patch was already ACK'ed by Robert Love, and the
only change in this version of the patch compared to the one he ACK'ed is
that this one also makes sure the preempt_count member is consistently
commented.
Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Both pmd_populate variants set two pmd entries before
ensuring that they are flushed from the cache. Separate
this functionality into __pmd_populate().
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This adds an I2C driver for the TPS6501x series of power management chips.
It's used on many OMAP based boards, and this driver has been widely used
in the Linux-OMAP trees over the last year or so.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch implements a number of smp_processor_id() cleanup ideas that
Arjan van de Ven and I came up with.
The previous __smp_processor_id/_smp_processor_id/smp_processor_id API
spaghetti was hard to follow both on the implementational and on the
usage side.
Some of the complexity arose from picking wrong names, some of the
complexity comes from the fact that not all architectures defined
__smp_processor_id.
In the new code, there are two externally visible symbols:
- smp_processor_id(): debug variant.
- raw_smp_processor_id(): nondebug variant. Replaces all existing
uses of _smp_processor_id() and __smp_processor_id(). Defined
by every SMP architecture in include/asm-*/smp.h.
There is one new internal symbol, dependent on DEBUG_PREEMPT:
- debug_smp_processor_id(): internal debug variant, mapped to
smp_processor_id().
Also, i moved debug_smp_processor_id() from lib/kernel_lock.c into a new
lib/smp_processor_id.c file. All related comments got updated and/or
clarified.
I have build/boot tested the following 8 .config combinations on x86:
{SMP,UP} x {PREEMPT,!PREEMPT} x {DEBUG_PREEMPT,!DEBUG_PREEMPT}
I have also build/boot tested x64 on UP/PREEMPT/DEBUG_PREEMPT. (Other
architectures are untested, but should work just fine.)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
kernel/sched.c: In function `__might_sleep':
kernel/sched.c:5461: warning: int format, long unsigned int arg (arg 3)
We expect irqs_disabled() to return an int (poor man's bool).
Acked-by: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Patch from Lennert Buytenhek
The IXP2000 has four timers, but if we're on an A-step IXP2800, timer
2 and 3 don't work. We need two timers for timekeeping (one for the
timer interrupt and one for tracking missed jiffies), so on early
IXP2800s we have no other choice but to use timer 1 and 4 for that,
but on all other IXP2000s we'd rather leave timer 4 free since that's
the only timer we can use for the watchdog.
So, on buggy IXP2000s (i.e. the A-step IXP2800) we use timer 4 for
tracking missed jiffies, and on all all non-buggy IXP2000s (i.e.
everything but the A-step IXP2800) we use timer 2.
On a pre-production IXP2800, this patch should print these messages
on boot:
Enabling IXP2800 erratum #25 workaround
Unable to use IXP2000 watchdog due to IXP2800 erratum #25
On any non-buggy IXP2800 (as well as on IXP2400s) you shouldn't see
anything at all, and the watchdog should be usable again.
Signed-off-by: Lennert Buytenhek
Signed-off-by: Deepak Saxena
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Catalin Marinas
This patch adds PCI support for the Versatile PB926 platform.
Signed-off-by: Colin King
Signed-off-by: Catalin Marinas
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Bellido Nicolas
Core support for AAEC-2000 based platforms.
This is an updated version of the previous patch, and takes
into account Russell's comments.
AAED-2000 default configuration will follow as soon
as some problems with the bootloader are sorted out...
Signed-off-by: Nicolas Bellido
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We need to re-initialise the stack pointers for undefined, IRQ
and abort mode handlers whenever we resume.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Create a temporary page table to startup secondary processors. This
page table must have a 1:1 virtual/physical mapping for the kernel
in addition to the standard mappings to ensure that the secondary
CPU can enable its MMU safely.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Catalin Marinas
The initial IB2 addresses did not depend on the IB2 base. This
patch defines them as (VERSATILE_IB2_BASE + offset).
Signed-off-by: Catalin Marinas
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Catalin Marinas
The GPIO base for Integrator/CP is different from the
Integrator/AP. This patch sets the correct value for
INTEGRATOR_GPIO_BASE.
Signed-off-by: Catalin Marinas
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Giorgio Padrin
The patch completes I2S GPIO alternate functions for PXA27x, adding I2S_SYSCLK.
File: pxa-regs.h .
Signed-off-by: Giorgio Padrin
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Mike Frysinger
the ELF_DATA define in both arm asm subdirs of linux/include/ contain a
semicolon at the end. this of course will cause any code that tries to use
ELF_DATA in assignment or comparison to fail. no other arch has a semicolon
in their ELF_DATA defines.
Signed-off-by: Mike Frysinger
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Deepak Saxena
This patch fixes the following warnings:
include/asm/arch/io.h: In function `insw':
include/asm/arch/io.h:78: warning: comparison of distinct pointer types
lacks acast
include/asm/arch/io.h:79: warning: comparison of distinct pointer types
lacks acast
include/asm/arch/io.h: In function `outsw':
include/asm/arch/io.h:103: warning: comparison of distinct pointer types
lacks a cast
include/asm/arch/io.h:104: warning: comparison of distinct pointer types
lacks a cast
include/asm/arch/io.h: In function `inw':
include/asm/arch/io.h:127: warning: comparison of distinct pointer types
lacks a cast
Signed-off-by: Deepak Saxena
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Ben Dooks
Add the register definitions for the s3c2440 NAND controller
to the s3c2410 NAND register definitions
Signed-off-by: Ben Dooks
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Sascha Hauer
This patch adds the defines for the i.MX PWM controller
Signed-off-by: Steven Scholz
Signed-off-by: Sascha Hauer
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Move the locking for copy_user_page() and clear_user_page() into
the implementations which require locking. For simple memcpy/
memset based implementations, the locking is extra overhead which
is not necessary, and prevents preemption occuring.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>
Various places in the ARM kernel implicitly assumed that kernel
stacks are always 8K due to hard coded constants. Replace these
constants with definitions.
Correct the allowable range of kernel stack pointer values within
the allocation. Arrange for the entire kernel stack to be zeroed,
not just the upper 4K if CONFIG_DEBUG_STACK_USAGE is set.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>
New file - asm-generic/signal.h. Contains declarations of
__sighandler_t, __sigrestore_t, SIG_DFL, SIG_IGN, SIG_ERR and default
definitions of SIG_BLOCK, SIG_UNBLOCK and SIG_SETMASK.
asm-*/signal.h switched to including it. The only exception is
asm-parisc/signal.h that wants its own declaration of __sighandler_t;
that one is left as-is.
asm-ppc64/signal.h required one more thing - unlike everybody else it
used __sigrestorer_t instead of usual __sigrestore_t. PPC64 switched to
common spelling.
Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
VMALLOC_START and VMALLOC_OFFSET are common between all ARM
machine classes. Move them into include/asm-arm/pgtable.h,
but allow a machine class to override them if required.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>
The attached patch moves the IRQ-related SA_xxx flags (namely, SA_PROBE,
SA_SAMPLE_RANDOM and SA_SHIRQ) from all the arch-specific headers to
linux/signal.h. This looks like a left-over after the irq-handling code
was consolidated. The code was moved to kernel/irq/*, but the flags are
still left per-arch.
Right now, adding a new IRQ flag to the arch-specific header, like this
patch does:
http://cvs.sourceforge.net/viewcvs.py/*checkout*/alsa/alsa-driver/utils/patches/pcsp-kernel-2.6.10-03.diff?rev=1.1
no longer works, it breaks the compilation for all other arches, unless you
add that flag to all the other arch-specific headers too. So I think such
a clean-up makes sense.
Signed-off-by: Stas Sergeev <stsp@aknet.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch eliminates all kernel BUGs, trims about 35k off the typical
kernel, and makes the system slightly faster.
Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The documentation on these values seems to be rather wrong.
These values have been determined by mere trial and error.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>
Patch from Olav Kongas
On ARM, the outX() and writeX() families of macros take the
result of cpu_to_leYY(), which is of restricted type __leYY,
and feed it to __raw_writeX(), which expect an argument of
unrestricted type. This results in 'sparse -Wbitwise'
warnings about incorrect types in assignments. Analogous
type mismatch warnings are issued for inX() and readX()
counterparts. The below patch resolves these warnings by
adding forced typecasts.
Signed-off-by: Olav Kongas
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Nicolas Pitre
This patch entirely reworks the kernel assistance for NPTL on ARM.
In particular this provides an efficient way to retrieve the TLS
value and perform atomic operations without any instruction emulation
nor special system call. This even allows for pre ARMv6 binaries to
be forward compatible with SMP systems without any penalty.
The problematic and performance critical operations are performed
through segment of kernel provided user code reachable from user space
at a fixed address in kernel memory. Those fixed entry points are
within the vector page so we basically get it for free as no extra
memory page is required and nothing else may be mapped at that
location anyway.
This is different from (but doesn't preclude) a full blown VDSO
implementation, however a VDSO would prevent some assembly tricks with
constants that allows for efficient branching to those code segments.
And since those code segments only use a few cycles before returning to
user code, the overhead of a VDSO far call would add a significant
overhead to such minimalistic operations.
The ARM_NR_set_tls syscall also changed number. This is done for two
reasons:
1) this patch changes the way the TLS value was previously meant to be
retrieved, therefore we ensure whatever library using the old way
gets fixed (they only exist in private tree at the moment since the
NPTL work is still progressing).
2) the previous number was allocated in a range causing an undefined
instruction trap on kernels not supporting that syscall and it was
determined that allocating it in a range returning -ENOSYS would be
much nicer for libraries trying to determine if the feature is
present or not.
Signed-off-by: Nicolas Pitre
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Lennert Buytenhek
Export ixp2000_pci_config_addr, to be used by the IXDP2800 platform
setup code to coordinate booting the master and slave NPU.
Signed-off-by: Lennert Buytenhek
Signed-off-by: Deepak Saxena
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We ignore the bottom 4 bits of the X resolution, so we should
round X resolutions up to the nearest multiple of 16.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>
We were supporting 24bpp. However, the pixel organisation in
memory was 0RGB, so it was 24bpp in 32bit words. This means
we're actually supporting 32bpp and not 24bpp.
Also, add a check to ensure that we don't exceed the available
framebuffer when changing display resolutions.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>
clk_get() comments can be confusing. Add extra explaination of
the dev and id parameters to ensure correct usage.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>
Patch from Deepak Saxena
The current memset() and memzero() macros on ARM reference the
incoming parameters more than once and this can cause uninted
side-effects. The issue was found while debugging SCTP protocol
and with the specific usage of memzero(skb_put(skb,size),size).
This call would call skb_put(skb,size) twice leading to badness.
The fixed version copies the incoming parameters into local
variables and uses those instead.
Signed-off-by: Deepak Saxena
Signed-off-by: Russell King
Patch from Lucas Correia Villa Real
Adds IISFCON definitions for the S3C2400 at
include/asm-arm/arch-s3c2400/regs-iis.h.
Signed-off-by: Lucas Correia Villa Real
Signed-off-by: Ben Dooks
Signed-off-by: Russell King
Patch from Lucas Correia Villa Real
The S3C2400 doesn't have a cpuid information stored anywhere. This patch adds
support to the S3C2400 at include/asm-arm/arch-s3c2400/uncompress.h by
initializing the cpuid variable to the S3C2410, as they share the same
routine. The GSTATUS1 pin is then used only if not compiling for the S3C2400.
Signed-off-by: Lucas Correia Villa Real
Signed-off-by: Ben Dooks
Signed-off-by: Russell King
Patch from Lucas Correia Villa Real
Adds a define to the SPI Card Select bit on the S3C2400 into
include/asm-arm/arch-s3c2410/regs-spi.h
Signed-off-by: Lucas Correia Villa Real
Signed-off-by: Russell King
Patch from Lucas Correia Villa Real
Adds DRAM refresh definitions and sets the BANKSIZE_MASK for the S3C2400 on
include/asm-arm/arch-s3c2400/regs-mem.h
Signed-off-by: Lucas Correia Villa Real
Signed-off-by: Ben Dooks
Signed-off-by: Russell King
ARM define FIRST_USER_ADDRESS as PAGE_SIZE (beyond the machine vectors when
they are mapped low), and use that definition in place of locally defined
MIN_MAP_ADDR.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix show_regs() to provide a backtrace. Provide a new __show_regs()
function which implements the common subset of show_regs() and die().
Add prototypes to asm-arm/system.h
Signed-off-by: Russell King <rmk@arm.linux.org.uk>
)
From: Russell King <rmk+lkml@arm.linux.org.uk>
The ARM dma_supported() is rather basic, and I don't think it takes into
account everything that it should do (eg, whether the mask agrees with what
we'd return for GFP_DMA allocations). Note this.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
