sched_clock is supposed to be initialized early - in the recently added
init_early platform hook. However, in doing so we end up calling
mod_timer() before the timer lists are initialized, resulting in an
oops.
Split the initialization in two - the part which the platform calls
early which starts things off. The addition of the timer can be
delayed until after we have more of the kernel initialized - when the
normal time sources are initialized.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add ARM support for the DMA debug infrastructure, which allows the
DMA API usage to be debugged.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The commit 6ac6b817f3 (ARM: pxa: encode
IRQ number into .nr_irqs) removed definition of ITE_LAST_IRQ which
caused the following build error:
CC arch/arm/common/it8152.o
arch/arm/common/it8152.c: In function 'it8152_init_irq':
arch/arm/common/it8152.c:86: error: 'IT8152_LAST_IRQ' undeclared (first use in this function)
arch/arm/common/it8152.c:86: error: (Each undeclared identifier is reported only once
arch/arm/common/it8152.c:86: error: for each function it appears in.)
make[2]: *** [arch/arm/common/it8152.o] Error 1
Defining the IT8152_LAST_IRQ in the arch/arm/include/hardware/it8152.c
fixes the build.
Signed-off-by: Mike Rapoport <mike@compulab.co.il>
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>
Replace the page_to_dma() and dma_to_page() macros with their PFN
equivalents. This allows us to map parts of memory which do not have
a struct page allocated to them to bus addresses. This will be used
internally by dma_alloc_coherent()/dma_alloc_writecombine().
Build tested on Versatile, OMAP1, IOP13xx and KS8695.
Tested-by: Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch fixes below build error by adding the missing asm/memory.h,
which is needed for arch_is_coherent().
$ make pxa3xx_defconfig; make
CC init/do_mounts_rd.o
In file included from include/linux/list_bl.h:5,
from include/linux/rculist_bl.h:7,
from include/linux/dcache.h:7,
from include/linux/fs.h:381,
from init/do_mounts_rd.c:3:
include/linux/bit_spinlock.h: In function 'bit_spin_unlock':
include/linux/bit_spinlock.h:61: error: implicit declaration of function 'arch_is_coherent'
make[1]: *** [init/do_mounts_rd.o] Error 1
make: *** [init] Error 2
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
sev is used to send wakeup event to other cores in ARMv6K and above.
This has been moved from platform specific part to standard common
ARM header file (asm/system.h). Also introduced wfi() and wfe().
Signed-off-by: Shiraz Hashim <shiraz.hashim@st.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This allows platforms to hook into the initialization early to setup
things like scheduler clocks, etc.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Rather than storing each machine init hook separately, store a
pointer to the machine description record and dereference this
instead. This pointer is only available while the init sections
are present, which is not a problem as we only use it from init
code.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Per subarch interrupt handler macros V3.
This patch breaks out code from the irq_handler macro
into arch_irq_handler and arch_irq_handler_default.
The macros are put in the header file "entry-macro-multi.S"
The arch_irq_handler_default macro is designed to be
used by irq_handler in entry-armv.S while arch_irq_handler
is suitable for per-subarch use.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Normally different ARM platform has different way to decode the IRQ
hardware status and demultiplex to the corresponding IRQ handler.
This is highly optimized by macro irq_handler in entry-armv.S, and
each machine defines their own macro to decode the IRQ number.
However, this prevents multiple machine classes to be built into a
single kernel.
By allowing each machine to specify thier own handler, and making
function pointer 'handle_arch_irq' to point to it at run time, this
can be solved. And introduce CONFIG_MULTI_IRQ_HANDLER to allow both
solutions to work.
Comparing with the highly optimized macro of irq_handler, the new
function must be written with care not to lose too much performance.
And the IPI stuff on SMP is expected to move to the provided arch
IRQ handler as well.
The assembly code to invoke handle_arch_irq is optimized by Russell
King.
Signed-off-by: Eric Miao <eric.miao@canonical.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
... and also remove misleading comment stating that this header is
auto-generated.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Uwe Kleine-Knig <u.kleine-koenig@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Provide common sched_clock() infrastructure for platforms to use to
create a 64-bit ns based sched_clock() implementation from a counter
running at a non-variable clock rate.
This implementation is based upon maintaining an epoch for the counter
and an epoch for the nanosecond time. When we desire a sched_clock()
time, we calculate the number of counter ticks since the last epoch
update, convert this to nanoseconds and add to the epoch nanoseconds.
We regularly refresh these epochs within the counter wrap interval.
We perform a similar calculation as above, and store the new epochs.
We read and write the epochs in such a way that sched_clock() can easily
(and locklessly) detect when an update is in progress, and repeat the
loading of these constants when they're known not to be stable. The
one caveat is that sched_clock() is not called in the middle of an
update. We achieve that by disabling IRQs.
Finally, if the clock rate is known at compile time, the counter to ns
conversion factors can be specified, allowing sched_clock() to be tightly
optimized. We ensure that these factors are correct by providing an
initialization function which performs a run-time check.
Acked-by: Peter Zijlstra <peterz@infradead.org>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Will Deacon <will.deacon@arm.com>
Tested-by: Mikael Pettersson <mikpe@it.uu.se>
Tested-by: Eric Miao <eric.y.miao@gmail.com>
Tested-by: Olof Johansson <olof@lixom.net>
Tested-by: Jamie Iles <jamie@jamieiles.com>
Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The hardware page tables use an XN bit 'execute never'. Historically,
we've had a Linux 'execute allow' bit, in the positive sense. Get rid
of this artifact as future hardware will continue to have the XN sense.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
FIRST_USER_PGD_NR is now unnecessary, as this has been replaced by
FIRST_USER_ADDRESS except in the architecture code. Fix up the last
usage of FIRST_USER_PGD_NR, and remove the definition.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We have two places where we create identity mappings - one when we bring
secondary CPUs online, and one where we setup some mappings for soft-
reboot. Combine these two into a single implementation. Also collect
the identity mapping deletion function.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This switches the ordering of the Linux vs hardware page tables in
each page, thereby eliminating some of the arithmetic in the page
table walks. As we now place the Linux page table at the beginning
of the page, we can deal with the offset in the pgt by simply masking
it away, along with the other control bits.
This also makes the arithmetic all be positive, rather than a mixture.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
When a CPU is hot unplugged, the generic tick code cleans up the
clock event device, but fails to call down to the device's set_mode
function to actually shut the device down.
To work around this, we've historically had a local_timer_stop()
callback out of the hotplug code. However, this adds needless
complexity when we have the clock event device itself available.
Explicitly call the clock event device's set_mode function with
CLOCK_EVT_MODE_UNUSED, so that the hardware can be cleanly shutdown
without any special external callbacks. When/if the generic code
is fixed, percpu_timer_stop() can be killed off.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* __fixup_smp_on_up has been modified with support for the
THUMB2_KERNEL case. For THUMB2_KERNEL only, fixups are split
into halfwords in case of misalignment, since we can't rely on
unaligned accesses working before turning the MMU on.
No attempt is made to optimise the aligned case, since the
number of fixups is typically small, and it seems best to keep
the code as simple as possible.
* Add a rotate in the fixup_smp code in order to support
CPU_BIG_ENDIAN, as suggested by Nicolas Pitre.
* Add an assembly-time sanity-check to ALT_UP() to ensure that
the content really is the right size (4 bytes).
(No check is done for ALT_SMP(). Possibly, this could be fixed
by splitting the two uses ot ALT_SMP() (ALT_SMP...SMP_UP versus
ALT_SMP...SMP_UP_B) into two macros. In the first case,
ALT_SMP needs to expand to >= 4 bytes, not == 4.)
* smp_mpidr.h (which implements ALT_SMP()/ALT_UP() manually due
to macro limitations) has not been modified: the affected
instruction (mov) has no 16-bit encoding, so the correct
instruction size is satisfied in this case.
* A "mode" parameter has been added to smp_dmb:
smp_dmb arm @ assumes 4-byte instructions (for ARM code, e.g. kuser)
smp_dmb @ uses W() to ensure 4-byte instructions for ALT_SMP()
This avoids assembly failures due to use of W() inside smp_dmb,
when assembling pure-ARM code in the vectors page.
There might be a better way to achieve this.
* Kconfig: make SMP_ON_UP depend on
(!THUMB2_KERNEL || !BIG_ENDIAN) i.e., THUMB2_KERNEL is now
supported, but only if !BIG_ENDIAN (The fixup code for Thumb-2
currently assumes little-endian order.)
Tested using a single generic realview kernel on:
ARM RealView PB-A8 (CONFIG_THUMB2_KERNEL={n,y})
ARM RealView PBX-A9 (SMP)
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
With "ARM: CPU hotplug: remove bug checks in platform_cpu_die()", we
now do not use hard_smp_processor_id(), we no longer need to read the
hardware processor ID. Remove the include providing this function.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
There is a certain amount of smp_prepare_cpus() which doesn't belong
in the platform support code - that is, code which is invariant to the
SMP implementation. Move this code into arch/arm/kernel/smp.c, and
add a platform_ prefix to the original function.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The IPI and local timer interrupts weren't being properly accounted
for in /proc/stat. Collect them from the irq_stat structure, and
return their sum.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This separates out the individual IPI interrupt counts from the
total IPI count, which allows better visibility of what IPIs are
being used for.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
As per x86, align the initial column according to how many IRQs we
have. Also, provide an english explaination for the 'LOC:' and
'IPI:' lines.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Move the ipi_count into irq_stat, which allows the ipi_data structure
to be entirely removed.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Provide __inc_irq_stat() and __get_irq_stat() to increment and
read the irq stat counters.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Since commit 3e4d3af501 "mm: stack based kmap_atomic()", it is no longer
necessary to carry an ad hoc version of kmap_atomic() added in commit
7e5a69e83b "ARM: 6007/1: fix highmem with VIPT cache and DMA" to cope
with reentrancy.
In fact, it is now actively wrong to rely on fixed kmap type indices
(namely KM_L1_CACHE) as kmap_atomic() totally ignores them now and a
concurrent instance of it may reuse any slot for any purpose.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Avoid adding nasty genirq-specific code to local timers to enable PPI
interrupts. Instead, provide a gic function to do this.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Provide a standard get_irqnr_preamble assembler macro for platforms
to use, which retrieves the base address of the GIC CPU interface
from gic_cpu_base_addr. Allow platforms to override this by defining
HAVE_GET_IRQNR_PREAMBLE.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Every architecture using the GIC has a gic_cpu_base_addr pointer for
GIC 0 for their entry assembly code to use to decode the cause of the
current interrupt. Move this into the common GIC code.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We don't need to re-pass the base address for the CPU interfaces to the
GIC for secondary CPUs, as it will never be different from the boot CPU
- and even if it was, we'd overwrite the boot CPU's base address.
Get rid of this argument, and rename to gic_secondary_init().
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Provide gic_init() which initializes the GIC distributor and current
CPU's GIC interface for the boot (or single) CPU.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We don't need to repeat the same definitions of the ioremap*(),
once in terms of __arch_ioremap() and again in terms of __arm_ioremap().
Instead, if the platform hasn't provided an __arch_ioremap, define
this to be __arm_ioremap, and only define the ioremap*() set using
__arch_ioremap.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Defining iounmap() with arguments prevents it from being used as a
function pointer, causing platforms to work around this. Instead,
define it to be a simple macro.
Do the same for __arch_io(re|un)map too.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch is the identical GIC demux implementation
merge V3. Instead of implementing same code over and
over simply share it in entry-macro-gic.S. The shared
code is based on the realview implementation.
Each GIC demux instance still has to setup the base address
of the controller using the get_irqnr_preamble macro. The
rest of the GIC specific code can be shared.
Signed-off-by: Magnus Damm <damm@opensource.se>
Acked-by: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The single-stepping code is currently different depending on whether
we are stepping over a breakpoint or a watchpoint. There is no good
reason for this, so let's sort it out.
This patch adds functions for enabling/disabling single-step for
a particular hw_breakpoint and integrates this with the exception
handling code.
Signed-off-by: Will Deacon <will.deacon@arm.com>
The watchpoint single-stepping code calls register_user_hw_breakpoint to
register a mismatch breakpoint for stepping over the watchpoint. This is
performed with preemption disabled, which is unsafe as we may end up scheduling
whilst in_atomic(). Furthermore, using the perf API is rather overkill since
we are already in the hw-breakpoint backend and only require access to reserved
breakpoints anyway.
This patch reworks the watchpoint stepping code so that we don't require
another perf_event for the mismatch breakpoint. Instead, we hold a separate
arch_hw_breakpoint_ctrl struct inside the watchpoint which is used exclusively
for stepping. We can check whether or not stepping is enabled when installing
or uninstalling the watchpoint and operate on the breakpoint accordingly.
Signed-off-by: Will Deacon <will.deacon@arm.com>
As our SMP implementation uses MESI protocols. Grouping together data
which is mostly only read together means that we avoid unnecessary
cache line bouncing when this code shares a cache line with other data.
In other words, cache lines associated with read-mostly data are
expected to spend most of their time in shared state.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* Fix kexec build failure with CONFIG_THUMB2_KERNEL.
* Avoids deprecated/forbidden sp and pc usage in for ARMv7
onwards, retaining compatibility with older architecture
versions.
* The pc value saved to newregs is now aligned on a predictable
instruction boundary.
(stmia { ... pc } or str pc has implementation-defined results
in most versions of the ARM architecutre, and is prohibited
(unpredictable) in Thumb-2.)
* Switch to named inline asm arguments (else I get readily
confused ...)
The resulting code should be compatible with all architecture
versions >= v3, with or without CONFIG_THUMB2_KERNEL.
Reviewed-by: Will Deacon <will.deacon@arm.com>
Tested-by: Mika Westerberg <mika.westerberg@iki.fi>
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Currently, the inline asm is passed &newregs->ARM_r0 as in input,
when modifying multiple fields of newregs.
It's plausible to assume that GCC will assume newregs->ARM_r0 is
modified when passed the address, but unfortunately this assumption
is incorrect.
Also, GCC has no way to guess that the other ARM_r* fields are
modified without the addition of a "memory" clobber.
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This allows us to use smp_cross_call() to trigger a number of different
software generated interrupts, rather than combining them all on one
SGI. Recover the SGI number via do_IPI.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
