The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications. For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.
After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out. Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.
Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
and are flagged as __cpuinit -- so if we remove the __cpuinit from
the arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
related content into no-ops as early as possible, since that will get
rid of these warnings. In any case, they are temporary and harmless.
This removes all the ARM uses of the __cpuinit macros from C code,
and all __CPUINIT from assembly code. It also had two ".previous"
section statements that were paired off against __CPUINIT
(aka .section ".cpuinit.text") that also get removed here.
[1] https://lkml.org/lkml/2013/5/20/589
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Pull timer core updates from Thomas Gleixner:
"The timer changes contain:
- posix timer code consolidation and fixes for odd corner cases
- sched_clock implementation moved from ARM to core code to avoid
duplication by other architectures
- alarm timer updates
- clocksource and clockevents unregistration facilities
- clocksource/events support for new hardware
- precise nanoseconds RTC readout (Xen feature)
- generic support for Xen suspend/resume oddities
- the usual lot of fixes and cleanups all over the place
The parts which touch other areas (ARM/XEN) have been coordinated with
the relevant maintainers. Though this results in an handful of
trivial to solve merge conflicts, which we preferred over nasty cross
tree merge dependencies.
The patches which have been committed in the last few days are bug
fixes plus the posix timer lot. The latter was in akpms queue and
next for quite some time; they just got forgotten and Frederic
collected them last minute."
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (59 commits)
hrtimer: Remove unused variable
hrtimers: Move SMP function call to thread context
clocksource: Reselect clocksource when watchdog validated high-res capability
posix-cpu-timers: don't account cpu timer after stopped thread runtime accounting
posix_timers: fix racy timer delta caching on task exit
posix-timers: correctly get dying task time sample in posix_cpu_timer_schedule()
selftests: add basic posix timers selftests
posix_cpu_timers: consolidate expired timers check
posix_cpu_timers: consolidate timer list cleanups
posix_cpu_timer: consolidate expiry time type
tick: Sanitize broadcast control logic
tick: Prevent uncontrolled switch to oneshot mode
tick: Make oneshot broadcast robust vs. CPU offlining
x86: xen: Sync the CMOS RTC as well as the Xen wallclock
x86: xen: Sync the wallclock when the system time is set
timekeeping: Indicate that clock was set in the pvclock gtod notifier
timekeeping: Pass flags instead of multiple bools to timekeeping_update()
xen: Remove clock_was_set() call in the resume path
hrtimers: Support resuming with two or more CPUs online (but stopped)
timer: Fix jiffies wrap behavior of round_jiffies_common()
...
Pull ARM updates from Russell King:
"This contains the usual updates from other people (listed below) and
the usual random muddle of miscellaneous ARM updates which cover some
low priority bug fixes and performance improvements.
I've started to put the pull request wording into the merge commits,
which are:
- NoMMU stuff:
This includes the following series sent earlier to the list:
- nommu-fixes
- R7 Support
- MPU support
I've left out the ARCH_MULTIPLATFORM/!MMU stuff that Arnd and I
were discussing today until we've reached a conclusion/that's had
some more review.
This is rebased (and re-tested) on your devel-stable branch because
otherwise there were going to be conflicts with Uwe's V7M work now
that you've merged that. I've included the fix for limiting MPU to
CPU_V7.
- Huge page support
These changes bring both HugeTLB support and Transparent HugePage
(THP) support to ARM. Only long descriptors (LPAE) are supported
in this series.
The code has been tested on an Arndale board (Exynos 5250).
- LPAE updates
Please pull these miscellaneous LPAE fixes I've been collecting for
a while now for 3.11. They've been tested and reviewed by quite a
few people, and most of the patches are pretty trivial. -- Will Deacon.
- arch_timer cleanups
Please pull these arch_timer cleanups I've been holding onto for a
while. They're the same as my last posting, but have been rebased
to v3.10-rc3.
- mpidr linearisation (multiprocessor id register - identifies which
CPU number we are in the system)
This patch series that implements MPIDR linearization through a
simple hashing algorithm and updates current cpu_{suspend}/{resume}
code to use the newly created hash structures to retrieve context
pointers. It represents a stepping stone for the implementation of
power management code on forthcoming multi-cluster ARM systems.
It has been tested on TC2 (dual cluster A15xA7 system), iMX6q,
OMAP4 and Tegra, with processors hitting low-power states requiring
warm-boot resume through the cpu_resume code path"
* 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (77 commits)
ARM: 7775/1: mm: Remove do_sect_fault from LPAE code
ARM: 7777/1: Avoid extra calls to the C compiler
ARM: 7774/1: Fix dtb dependency to use order-only prerequisites
ARM: 7770/1: remove residual ARMv2 support from decompressor
ARM: 7769/1: Cortex-A15: fix erratum 798181 implementation
ARM: 7768/1: prevent risks of out-of-bound access in ASID allocator
ARM: 7767/1: let the ASID allocator handle suspended animation
ARM: 7766/1: versatile: don't mark pen as __INIT
ARM: 7765/1: perf: Record the user-mode PC in the call chain.
ARM: 7735/2: Preserve the user r/w register TPIDRURW on context switch and fork
ARM: kernel: implement stack pointer save array through MPIDR hashing
ARM: kernel: build MPIDR hash function data structure
ARM: mpu: Ensure that MPU depends on CPU_V7
ARM: mpu: protect the vectors page with an MPU region
ARM: mpu: Allow enabling of the MPU via kconfig
ARM: 7758/1: introduce config HAS_BANDGAP
ARM: 7757/1: mm: don't flush icache in switch_mm with hardware broadcasting
ARM: 7751/1: zImage: don't overwrite ourself with a page table
ARM: 7749/1: spinlock: retry trylock operation if strex fails on free lock
ARM: 7748/1: oabi: handle faults when loading swi instruction from userspace
...
EDMA supports a cross bar which provides ability
to mux additional events into physical channels
present in the channel controller.
This is required when the number of events present
in the system are more than number of available
physical channels.
Changes by Joel:
* Split EDMA xbar support out of original EDMA DT parsing patch
to keep it easier for review.
* Rewrite shift and offset calculation.
Suggested-by: Sekhar Nori <nsekhar@ti.com>
Suggested by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Joel A Fernandes <joelagnel@ti.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
[nsekhar@ti.com: fix checkpatch errors and a minor coding improvement]
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Adds support for parsing the TI EDMA DT data into the required EDMA
private API platform data. Enables runtime PM support to initialize
the EDMA hwmod. Enables build on OMAP.
Changes by Joel:
* Setup default one-to-one mapping for queue_priority and queue_tc
mapping as discussed in [1].
* Split out xbar stuff to separate patch. [1]
* Dropped unused DT helper to convert to array
* Fixed dangling pointer issue with Sekhar's changes
[1] https://patchwork.kernel.org/patch/2226761/
Signed-off-by: Matt Porter <mporter@ti.com>
[nsekhar@ti.com: fix checkpatch errors, build breakages. Introduce
edma_setup_info_from_dt() as part of that effort]
Signed-off-by: Joel A Fernandes <joelagnel@ti.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Use devm_ioremap_resource instead of reques_mem_region()/ioremap(),
devm_request_irq() instead of request_irq() and kzalloc() calls to
devm_kzalloc().
This ensures more consistent error values and simplifies error paths.
Signed-off-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>
[nsekhar@ti.com: add missing err.h include]
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Fix build on OMAP, the irqs are undefined on AM33xx.
These error interrupt handlers were hardcoded as disabled
so since they are unused code, simply remove them.
Signed-off-by: Matt Porter <mporter@ti.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Move mach-davinci/dma.c to common/edma.c so it can be used
by OMAP (specifically AM33xx) as well.
Signed-off-by: Matt Porter <mporter@ti.com>
Acked-by: Chris Ball <cjb@laptop.org> # davinci_mmc.c
Acked-by: Mark Brown <broonie@linaro.org>
Acked-by: Olof Johansson <olof@lixom.net>
[nsekhar@ti.com: dropped davinci sffsdr changes]
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Nothing about the sched_clock implementation in the ARM port is
specific to the architecture. Generalize the code so that other
architectures can use it by selecting GENERIC_SCHED_CLOCK.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
[jstultz: Merge minor collisions with other patches in my tree]
Signed-off-by: John Stultz <john.stultz@linaro.org>
The smp_init_cpus method in the smp_operations structure is optional
and can be omitted entirely.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The CPU and cluster numbers (MPIDR affinity levels 0 and 1) may have
at most 8 bits each.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Pull ARM fixes from Russell King:
"A small number of fixes for stuff from the last merge window, and in
one case (IRQ time accounting) the previous merge window."
* 'fixes' of git://git.linaro.org/people/rmk/linux-arm:
ARM: 7720/1: ARM v6/v7 cmpxchg64 shouldn't clear upper 32 bits of the old/new value
ARM: 7715/1: MCPM: adapt to GIC changes after upstream merge
ARM: 7714/1: mmc: mmci: Ensure return value of regulator_enable() is checked
ARM: 7712/1: Remove trailing whitespace in arch/arm/Makefile
ARM: 7711/1: dove: fix Dove cpu type from V7 to PJ4
ARM: finally enable IRQ time accounting config
Since commit c0114709ed ("irqchip: gic: Perform the gic_secondary_init()
call via CPU notifier") it is no longer required nor possible to call
gic_secondary_init() from platform code.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Pull ARM SoC late cleanups from Arnd Bergmann:
"These are cleanups and smaller changes that either depend on earlier
feature branches or came in late during the development cycle. We
normally try to get all cleanups early, so these are the exceptions:
- A follow-up on the clocksource reworks, hopefully the last time we
need to merge clocksource subsystem changes through arm-soc.
A first set of patches was part of the original 3.10 arm-soc
cleanup series because of interdependencies with timer drivers now
moved out of arch/arm.
- Migrating the SPEAr13xx platform away from using auxdata for DMA
channel descriptions towards using information in device tree,
based on the earlier SPEAr multiplatform series
- A few follow-ups on the Atmel SAMA5 support and other changes for
Atmel at91 based on the larger at91 reworks.
- Moving the armada irqchip implementation to drivers/irqchip
- Several OMAP cleanups following up on the larger series already
merged in 3.10."
* tag 'cleanup-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (50 commits)
ARM: OMAP4: change the device names in usb_bind_phy
ARM: OMAP2+: Fix mismerge for timer.c between ff931c82 and da4a686a
ARM: SPEAr: conditionalize SMP code
ARM: arch_timer: Silence debug preempt warnings
ARM: OMAP: remove unused variable
serial: amba-pl011: fix !CONFIG_DMA_ENGINE case
ata: arasan: remove the need for platform_data
ARM: at91/sama5d34ek.dts: remove not needed compatibility string
ARM: at91: dts: add MCI DMA support
ARM: at91: dts: add i2c dma support
ARM: at91: dts: set #dma-cells to the correct value
ARM: at91: suspend both memory controllers on at91sam9263
irqchip: armada-370-xp: slightly cleanup irq controller driver
irqchip: armada-370-xp: move IRQ handler to avoid forward declaration
irqchip: move IRQ driver for Armada 370/XP
ARM: mvebu: move L2 cache initialization in init_early()
devtree: add binding documentation for sp804
ARM: integrator-cp: convert use CLKSRC_OF for timer init
ARM: versatile: use OF init for sp804 timer
ARM: versatile: add versatile dtbs to dtbs target
...
Pull ARM platform specific firmware interfaces from Olof Johansson:
"Two platforms, bcm and exynos have their own firmware interfaces using
the "secure monitor call", this adds support for those.
We had originally planned to have a third set of patches in here,
which would extend support for the existing generic "psci" call that
is used on multiple platforms as well as Xen and KVM guests, but that
ended up getting dropped because the patches were not ready in time."
* tag 'firmware-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
ARM: bcm: mark bcm_kona_smc_init as __init
ARM: bcm281xx: Add DT support for SMC handler
ARM: bcm281xx: Add L2 cache enable code
ARM: EXYNOS: Add secure firmware support to secondary CPU bring-up
ARM: EXYNOS: Add IO mapping for non-secure SYSRAM.
ARM: EXYNOS: Add support for Exynos secure firmware
ARM: EXYNOS: Add support for secure monitor calls
ARM: Add interface for registering and calling firmware-specific operations
The full mcpm layer is not likely to be relevant to v6 based
platforms, so a multiplatform kernel won't use that code if booted
on v6 hardware.
This patch modifies the AFLAGS for affected mcpm .S files to
specify armv7-a explicitly for that code.
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Now that the cluster power API is in place, we can use it for SMP secondary
bringup and CPU hotplug in a generic fashion.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Instead of requiring the first man to be elected in advance (which
can be suboptimal in some situations), this patch uses a per-
cluster mutex to co-ordinate selection of the first man.
This should also make it more feasible to reuse this code path for
asynchronous cluster resume (as in CPUidle scenarios).
We must ensure that the vlock data doesn't share a cacheline with
anything else, or dirty cache eviction could corrupt it.
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
This patch adds a simple low-level voting mutex implementation
to be used to arbitrate during first man selection when no load/store
exclusive instructions are usable.
For want of a better name, these are called "vlocks". (I was
tempted to call them ballot locks, but "block" is way too confusing
an abbreviation...)
There is no function to wait for the lock to be released, and no
vlock_lock() function since we don't need these at the moment.
These could straightforwardly be added if vlocks get used for other
purposes.
For architectural correctness even Strongly-Ordered memory accesses
require barriers in order to guarantee that multiple CPUs have a
coherent view of the ordering of memory accesses. Whether or not
this matters depends on hardware implementation details of the
memory system. Since the purpose of this code is to provide a clean,
generic locking mechanism with no platform-specific dependencies the
barriers should be present to avoid unpleasant surprises on future
platforms.
Note:
* When taking the lock, we don't care about implicit background
memory operations and other signalling which may be pending,
because those are not part of the critical section anyway.
A DMB is sufficient to ensure correctly observed ordering if
the explicit memory accesses in vlock_trylock.
* No barrier is required after checking the election result,
because the result is determined by the store to
VLOCK_OWNER_OFFSET and is already globally observed due to the
barriers in voting_end. This means that global agreement on
the winner is guaranteed, even before the winner is known
locally.
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
This provides helper methods to coordinate between CPUs coming down
and CPUs going up, as well as documentation on the used algorithms,
so that cluster teardown and setup
operations are not done for a cluster simultaneously.
For use in the power_down() implementation:
* __mcpm_cpu_going_down(unsigned int cluster, unsigned int cpu)
* __mcpm_outbound_enter_critical(unsigned int cluster)
* __mcpm_outbound_leave_critical(unsigned int cluster)
* __mcpm_cpu_down(unsigned int cluster, unsigned int cpu)
The power_up_setup() helper should do platform-specific setup in
preparation for turning the CPU on, such as invalidating local caches
or entering coherency. It must be assembler for now, since it must
run before the MMU can be switched on. It is passed the affinity level
for which initialization should be performed.
Because the mcpm_sync_struct content is looked-up and modified
with the cache enabled or disabled depending on the code path, it is
crucial to always ensure proper cache maintenance to update main memory
right away. The sync_cache_*() helpers are used to that end.
Also, in order to prevent a cached writer from interfering with an
adjacent non-cached writer, we ensure each state variable is located to
a separate cache line.
Thanks to Nicolas Pitre and Achin Gupta for the help with this
patch.
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Will Deacon <will.deacon@arm.com>
This is the basic API used to handle the powering up/down of individual
CPUs in a (multi-)cluster system. The platform specific backend
implementation has the responsibility to also handle the cluster level
power as well when the first/last CPU in a cluster is brought up/down.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
CPUs in cluster based systems, such as big.LITTLE, have special needs
when entering the kernel due to a hotplug event, or when resuming from
a deep sleep mode.
This is vectorized so multiple CPUs can enter the kernel in parallel
without serialization.
The mcpm prefix stands for "multi cluster power management", however
this is usable on single cluster systems as well. Only the basic
structure is introduced here. This will be extended with later patches.
In order not to complexify things more than they currently have to,
the planned work to make runtime adjusted MPIDR based indexing and
dynamic memory allocation for cluster states is postponed to a later
cycle. The MAX_NR_CLUSTERS and MAX_CPUS_PER_CLUSTER static definitions
should be sufficient for those systems expected to be available in the
near future.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Move the integrator-cp timer init to timer-sp.c and use CLKSRC_OF. There is
no reason to use the aliases, so drop them from the init code.
The integrator-cp timers are mistakenly called sp804 timers in the dts, but
in fact they are not sp804 dual timers, but single timers with the same
programming model. Fix the dts to reflect this.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
This adds CLKSRC_OF based init for sp804 timer. The clock initialization is
refactored to support retrieving the clock(s) from the DT.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
