This enables local timer (AKA: private timer) support for
all u8500 based hardware using DT.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This SSP Controller supports a number of serial communication methods
and as such cannot be registered using of_register_spi_devices.
Instead we register it simply as a primecell device.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This provides PL310 Level 2 Cache Controller Device Tree
support for all u8500 based devices.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Enables the 3 UARTs found on a u8500 using DT.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This enables the embedded GIC on all u8500 based hardware using DT.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This adds all devices that are normally present through the
u8500_init_machine function in the device tree as well, which
will duplicate the devices that are visible.
This will not do much by itself because the device from the
device tree are not matched by any device driver until they
are converted as well. The next step is to move over one
device at a time to actually be used from the device tree
instead of the hardcoded device using auxdata to pass the
correct platform_data.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
db8500.dtsi can be used by all systems with a db8500 or
db9500 SoC, while snowball.dts is board specific.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This lets us move over evertything to device tree one by one.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This provides very basic Device Tree support for ST-Ericsson's
low-cost development platform, Snowball. If Device Tree for
ux500 is enabled and the correct board is configured within the
Device Tree blob, the correct *_init_machine() will be called.
This patch is based on some original work completed by:
Niklas Hernaeus <niklas.hernaeus@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Niklas Hernaeus <niklas.hernaeus@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
mach-ux500/timer.c lacked the inclusion of mach/irqs.h, and thus
failed to compile. Fix it and also remove an unused variable.
Test compiled only.
Reported-by: Lee Jones <lee.jones@linaro.org>
Cc: Arnd Bergman <arnd@arndb.de>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
* 'local_timers-for-arm-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms:
ARM: local timers: make the runtime registration interface mandatory
ARM: local timers: convert MSM to runtime registration interface
ARM: local timers: convert exynos to runtime registration interface
ARM: smp_twd: remove old local timer interface
ARM: imx6q: convert to twd_local_timer_register() interface
ARM: highbank: convert to twd_local_timer_register() interface
ARM: ux500: convert to twd_local_timer_register() interface
ARM: shmobile: convert to twd_local_timer_register() interface
ARM: tegra: convert to twd_local_timer_register() interface
ARM: plat-versatile: convert to twd_local_timer_register() interface
ARM: OMAP4: convert to twd_local_timer_register() interface
ARM: smp_twd: add device tree support
ARM: smp_twd: add runtime registration support
ARM: local timers: introduce a new registration interface
ARM: smp_twd: make local_timer_stop a symbol instead of a #define
Remove all traces of the compile-time local timer interface,
and make the runtime selection mandatory.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Convert the MSM timers to the runtime registration interface.
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Tested-by: David Brown <davidb@codeaurora.org>
Acked-by: David Brown <davidb@codeaurora.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Convert the Exynos MCT timers to the runtime registration interface.
Tested on Origen.
Cc: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Now that all users of the previous local timer interface
have been converted to the runtime registration API, make
this interface the only one supported for this driver.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Add support for the new smp_twd runtime registration interface
to the imx6q platforms, and remove the old compile-time support.
The imx6q DTS file is updated to match the TWD DT documentation.
Also present in this patch a DTS fix to the timer interrupt routing
(the PPI connection uses bits [15:8]) and trigger (rising edge).
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Add support for the new smp_twd runtime registration interface
to the highbank platforms, and remove the old compile-time support.
The highbank DTS file is updated to match the TWD DT documentation
and fixes the timer trigger (rising edge).
Acked-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Add support for the new smp_twd runtime registration interface
to the ux500 platforms, and remove the old compile-time support.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Add support for the new smp_twd runtime registration interface
to the shmobile platforms, and remove the old compile-time support.
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Add support for the new smp_twd runtime registration interface
to the tegra platforms, and remove the old compile-time support.
Tested on Harmony.
Acked-by: Stephen Warren <swarren@nvidia.com>
Cc: Colin Cross <ccross@android.com>
Cc: Olof Johansson <olof@lixom.net>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Add support for the new smp_twd runtime registration interface
to the RealView/VE platforms, and remove the old compile-time support.
Tested on EB11MP.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Add support for the new smp_twd runtime registration interface
to the OMAP4 platforms, and remove the old compile-time support.
Tested on Panda.
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Add bindings to support DT discovery of the ARM Timer Watchdog
(aka TWD). Only the timer side is converted by this patch.
Acked-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Add support for the new registration interface to smp_twd.
Platforms can populate a struct twd_local_timer with MMIO
and IRQ resources, and then call twd_local_timer_register()
to have the timer registered with the core.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
In order to switch to a runtime selectable local timer,
add a registration interface that timer drivers can use to
register to the core.
local_timer_setup() and local_timer_stop() are made weak symbols
in order not to break existing setups.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
When CONFIG_HAVE_ARM_TWD is selected, local_timer_stop is a #define,
while all other local timers are using a real function.
Convert it to an alias of twd_timer_stop, as it helps converting
all local timers to another internal API in a sane way.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
* ux500/timers:
ARM: plat-nomadik: modernize MTU timer
ARM: plat-nomadik: handle clocking properly
ARM: plat-nomadik: get rid of global mtu base pointer
Try to map TWD registers basing on a "arm,*-twd-timer" Device Tree
node. This overrides existing twd_base value.
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
This patch gets rid of the MMIO_P2V and __MMIO_P2V macros,
defining constant virtual base for motherboard and tile
peripherals instead.
Additionally, in preparation for the new motherboard memory
map, the motherboard peripherals are using base pointers
calculated in runtime, instead of compile-time calculated
values.
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
The majority of them are regression fixes for stuff that broke during
the merge 3.3 window.
The notable ones are:
* The at91 ata drivers both broke because of an earlier cleanup patch that
some other patches were based on. Jean-Christophe decided to remove
the legacy at91_ide driver and fix the new-style at91-pata driver while
keeping the cleanup patch. I almost rejected the patches for being too
late and too big but in the end decided to accept them because they
fix a regression.
* A patch fixing build breakage from the sysdev-to-device conversion
colliding with other changes touches a number of mach-s3c files.
* b0654037 "ARM: orion: Fix Orion5x GPIO regression from MPP cleanup"
is a mechanical change that unfortunately touches a lot of lines
that should up in the diffstat.
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Merge tag 'fixes-3.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
These are the bug fixes that have accumulated since 3.3-rc3 in arm-soc.
The majority of them are regression fixes for stuff that broke during
the merge 3.3 window.
The notable ones are:
* The at91 ata drivers both broke because of an earlier cleanup patch that
some other patches were based on. Jean-Christophe decided to remove
the legacy at91_ide driver and fix the new-style at91-pata driver while
keeping the cleanup patch. I almost rejected the patches for being too
late and too big but in the end decided to accept them because they
fix a regression.
* A patch fixing build breakage from the sysdev-to-device conversion
colliding with other changes touches a number of mach-s3c files.
* b0654037 "ARM: orion: Fix Orion5x GPIO regression from MPP cleanup"
is a mechanical change that unfortunately touches a lot of lines
that should up in the diffstat.
* tag 'fixes-3.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (28 commits)
ARM: at91: drop ide driver in favor of the pata one
pata/at91: use newly introduced SMC accessors
ARM: at91: add accessor to manage SMC
ARM: at91:rtc/rtc-at91sam9: ioremap register bank
ARM: at91: USB AT91 gadget registration for module
ep93xx: fix build of vision_ep93xx.c
ARM: OMAP2xxx: PM: fix OMAP2xxx-specific UART idle bug in v3.3
ARM: orion: Fix USB phy for orion5x.
ARM: orion: Fix Orion5x GPIO regression from MPP cleanup
ARM: EXYNOS: Add cpu-offset property in gic device tree node
ARM: EXYNOS: Bring exynos4-dt up to date
ARM: OMAP3: cm-t35: fix section mismatch warning
ARM: OMAP2: Fix the OMAP2 only build break seen with 2011+ ARM tool-chains
ARM: tegra: paz00: fix wrong UART port on mini-pcie plug
ARM: tegra: paz00: fix wrong SD1 power gpio
i2c: tegra: Add devexit_p() for remove
ARM: EXYNOS: Correct M-5MOLS sensor clock frequency on Universal C210 board
ARM: EXYNOS: Correct framebuffer window size on Nuri board
ARM: SAMSUNG: Fix missing api-change from subsys_interface change
ARM: EXYNOS: Fix "warning: initialization from incompatible pointer type"
...
1) VETH_INFO_PEER netlink attribute needs to have it's size validated,
from Thomas Graf.
2) 'poll' module option of bnx2x driver crashes the machine, just remove
it. From Michal Schmidt.
3) ks8851_mll driver reads the irq number from two places, but only
initializes one of them, oops. Use only one location and fix this
problem, from Jan Weitzel.
4) Fix buffer overrun and unicast sterring bugs in mellanox mlx4 driver,
from Eugenia Emantayev.
5) Swapped kcalloc() args in RxRPC and mlx4, from Axel Lin.
6) PHY MDIO device name regression fixes from Florian Fainelli.
7) If the wake event IRQ line is different from the netdevice one, we
have to properly route it to the stmmac interrupt handler. From
Francesco Virlinzi.
8) Fix rwlock lock initialization ordering bug in mac80211, from
Mohammed Shafi Shajakhan.
9) TCP lost_cnt can get out of sync, and in fact go negative, in certain
circumstances. Fix the way we specify what sequence range to operate
on in tcp_sacktag_one() to fix this bug. From Neal Cardwell.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (27 commits)
net/ethernet: ks8851_mll fix irq handling
veth: Enforce minimum size of VETH_INFO_PEER
stmmac: update the driver version to Feb 2012 (v2)
stmmac: move hw init in the probe (v2)
stmmac: request_irq when use an ext wake irq line (v2)
stmmac: do not discard frame on dribbling bit assert
ipheth: Add iPhone 4S
mlx4: add unicast steering entries to resource_tracker
mlx4: fix QP tree trashing
mlx4: fix buffer overrun
3c59x: shorten timer period for slave devices
netpoll: netpoll_poll_dev() should access dev->flags
RxRPC: Fix kcalloc parameters swapped
bnx2x: remove the 'poll' module option
tcp: fix tcp_shifted_skb() adjustment of lost_cnt_hint for FACK
ks8851: Fix NOHZ local_softirq_pending 08 warning
bnx2x: fix bnx2x_storm_stats_update() on big endian
ixp4xx-eth: fix PHY name to match MDIO bus name
octeon: fix PHY name to match MDIO bus name
fec: fix PHY name to match fixed MDIO bus name
...
method for register cache initialisation is used. Only affects a fairly
small proportion of users that both don't use explicit register defaults
and do use the cache.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap
Fixes a bootstrapping issue for some registers when a less commonly used
method for register cache initialisation is used. Only affects a fairly
small proportion of users that both don't use explicit register defaults
and do use the cache.
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
regmap: Fix cache defaults initialization from raw cache defaults
and also fixes stale inode mode bits on eCryptfs inodes after a POSIX ACL was
set on the lower filesystem's inode.
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Merge tag 'ecryptfs-3.3-rc4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs
Fixes maximum filename length and filesystem type reporting in statfs() calls
and also fixes stale inode mode bits on eCryptfs inodes after a POSIX ACL was
set on the lower filesystem's inode.
* tag 'ecryptfs-3.3-rc4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs:
ecryptfs: remove the second argument of k[un]map_atomic()
eCryptfs: Copy up lower inode attrs after setting lower xattr
eCryptfs: Improve statfs reporting
Here are a few more fixes for powerpc. Some are regressions, the rest
is simple/obvious/nasty enough that I deemed it good to go now.
Here's also step one of deprecating legacy iSeries support: we are
removing it from the main defconfig.
Nobody seems to be using it anymore and the code is nasty to maintain,
(involves horrible hacks in various low level areas of the kernel) so we
plan to actually rip it out at some point. For now let's just avoid
building it by default. Stephen will proceed to do the actual removal
later (probably 3.4 or 3.5).
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
powerpc/perf: power_pmu_start restores incorrect values, breaking frequency events
powerpc/adb: Use set_current_state()
powerpc: Disable interrupts early in Program Check
powerpc: Remove legacy iSeries from ppc64_defconfig
powerpc/fsl/pci: Fix PCIe fixup regression
powerpc: Fix kernel log of oops/panic instruction dump
One regression fix for SR-IOV on PPC and a couple of misc fixes from
Yinghai.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci:
PCI: Fix pci cardbus removal
PCI: set pci sriov page size before reading SRIOV BAR
PCI: workaround hard-wired bus number V2
3 radeon fixes, I have some exynos fixes to push later but I'll queue
them separately once I've looked them over a bit.
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
drm/radeon/kms: fix MSI re-arm on rv370+
drm/radeon/kms/atom: bios scratch reg handling updates
drm/radeon/kms: drop lock in return path of radeon_fence_count_emitted.
After all the FPU state cleanups and finally finding the problem that
caused all our FPU save/restore problems, this re-introduces the
preloading of FPU state that was removed in commit b3b0870ef3 ("i387:
do not preload FPU state at task switch time").
However, instead of simply reverting the removal, this reimplements
preloading with several fixes, most notably
- properly abstracted as a true FPU state switch, rather than as
open-coded save and restore with various hacks.
In particular, implementing it as a proper FPU state switch allows us
to optimize the CR0.TS flag accesses: there is no reason to set the
TS bit only to then almost immediately clear it again. CR0 accesses
are quite slow and expensive, don't flip the bit back and forth for
no good reason.
- Make sure that the same model works for both x86-32 and x86-64, so
that there are no gratuitous differences between the two due to the
way they save and restore segment state differently due to
architectural differences that really don't matter to the FPU state.
- Avoid exposing the "preload" state to the context switch routines,
and in particular allow the concept of lazy state restore: if nothing
else has used the FPU in the meantime, and the process is still on
the same CPU, we can avoid restoring state from memory entirely, just
re-expose the state that is still in the FPU unit.
That optimized lazy restore isn't actually implemented here, but the
infrastructure is set up for it. Of course, older CPU's that use
'fnsave' to save the state cannot take advantage of this, since the
state saving also trashes the state.
In other words, there is now an actual _design_ to the FPU state saving,
rather than just random historical baggage. Hopefully it's easier to
follow as a result.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This moves the bit that indicates whether a thread has ownership of the
FPU from the TS_USEDFPU bit in thread_info->status to a word of its own
(called 'has_fpu') in task_struct->thread.has_fpu.
This fixes two independent bugs at the same time:
- changing 'thread_info->status' from the scheduler causes nasty
problems for the other users of that variable, since it is defined to
be thread-synchronous (that's what the "TS_" part of the naming was
supposed to indicate).
So perfectly valid code could (and did) do
ti->status |= TS_RESTORE_SIGMASK;
and the compiler was free to do that as separate load, or and store
instructions. Which can cause problems with preemption, since a task
switch could happen in between, and change the TS_USEDFPU bit. The
change to TS_USEDFPU would be overwritten by the final store.
In practice, this seldom happened, though, because the 'status' field
was seldom used more than once, so gcc would generally tend to
generate code that used a read-modify-write instruction and thus
happened to avoid this problem - RMW instructions are naturally low
fat and preemption-safe.
- On x86-32, the current_thread_info() pointer would, during interrupts
and softirqs, point to a *copy* of the real thread_info, because
x86-32 uses %esp to calculate the thread_info address, and thus the
separate irq (and softirq) stacks would cause these kinds of odd
thread_info copy aliases.
This is normally not a problem, since interrupts aren't supposed to
look at thread information anyway (what thread is running at
interrupt time really isn't very well-defined), but it confused the
heck out of irq_fpu_usable() and the code that tried to squirrel
away the FPU state.
(It also caused untold confusion for us poor kernel developers).
It also turns out that using 'task_struct' is actually much more natural
for most of the call sites that care about the FPU state, since they
tend to work with the task struct for other reasons anyway (ie
scheduling). And the FPU data that we are going to save/restore is
found there too.
Thanks to Arjan Van De Ven <arjan@linux.intel.com> for pointing us to
the %esp issue.
Cc: Arjan van de Ven <arjan@linux.intel.com>
Reported-and-tested-by: Raphael Prevost <raphael@buro.asia>
Acked-and-tested-by: Suresh Siddha <suresh.b.siddha@intel.com>
Tested-by: Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The AMD K7/K8 CPUs don't save/restore FDP/FIP/FOP unless an exception is
pending. In order to not leak FIP state from one process to another, we
need to do a floating point load after the fxsave of the old process,
and before the fxrstor of the new FPU state. That resets the state to
the (uninteresting) kernel load, rather than some potentially sensitive
user information.
We used to do this directly after the FPU state save, but that is
actually very inconvenient, since it
(a) corrupts what is potentially perfectly good FPU state that we might
want to lazy avoid restoring later and
(b) on x86-64 it resulted in a very annoying ordering constraint, where
"__unlazy_fpu()" in the task switch needs to be delayed until after
the DS segment has been reloaded just to get the new DS value.
Coupling it to the fxrstor instead of the fxsave automatically avoids
both of these issues, and also ensures that we only do it when actually
necessary (the FP state after a save may never actually get used). It's
simply a much more natural place for the leaked state cleanup.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Yes, taking the trap to re-load the FPU/MMX state is expensive, but so
is spending several days looking for a bug in the state save/restore
code. And the preload code has some rather subtle interactions with
both paravirtualization support and segment state restore, so it's not
nearly as simple as it should be.
Also, now that we no longer necessarily depend on a single bit (ie
TS_USEDFPU) for keeping track of the state of the FPU, we migth be able
to do better. If we are really switching between two processes that
keep touching the FP state, save/restore is inevitable, but in the case
of having one process that does most of the FPU usage, we may actually
be able to do much better than the preloading.
In particular, we may be able to keep track of which CPU the process ran
on last, and also per CPU keep track of which process' FP state that CPU
has. For modern CPU's that don't destroy the FPU contents on save time,
that would allow us to do a lazy restore by just re-enabling the
existing FPU state - with no restore cost at all!
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After passing through a ->setxattr() call, eCryptfs needs to copy the
inode attributes from the lower inode to the eCryptfs inode, as they
may have changed in the lower filesystem's ->setxattr() path.
One example is if an extended attribute containing a POSIX Access
Control List is being set. The new ACL may cause the lower filesystem to
modify the mode of the lower inode and the eCryptfs inode would need to
be updated to reflect the new mode.
https://launchpad.net/bugs/926292
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Reported-by: Sebastien Bacher <seb128@ubuntu.com>
Cc: John Johansen <john.johansen@canonical.com>
Cc: <stable@vger.kernel.org>
