ARM920 and ARM926 save four registers, not three. Fix the size of
the suspend region required.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
r1 stores the v:p offset from the CPU invariant resume code, and is
expected to be preserved by the CPU specific code. Overwriting it is
not a good idea.
We've managed to get away with it on sa1100 platforms because most
happen to have PHYS_OFFSET == PAGE_OFFSET, but that may not be the
case depending on kernel configuration. So fix this latent bug.
This fixes xsc3 as well which was saving and restoring this register
independently.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
cpu_v7_reset disables the MMU and then branches to the provided address.
On Thumb-2 kernels, we should take care to clear the Thumb Exception
enable bit in the System Control Register, otherwise this may wreak
havok in the code to which we are branching (for example, an ARM kernel
image via kexec).
Reviewed-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
PGDIR_SHIFT and PMD_SHIFT for the classic 2-level page table format have
the same value (21). This patch converts the PGDIR_* uses in the kernel
to the PMD_* equivalent so that LPAE builds can reuse the same code.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This function can be called during boot to increase the size of the consistent
DMA region above it's default value of 2MB. It must be called before the memory
allocator is initialised, i.e. before any core_initcall.
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
This patch is a workaround for the 364296 ARM1136 r0p2 erratum (possible
cache data corruption with hit-under-miss enabled). It sets the
undocumented bit 31 in the auxiliary control register and the FI bit in
the control register, thus disabling hit-under-miss without putting the
processor into full low interrupt latency mode.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Siarhei Siamashka <siarhei.siamashka@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
With the UM_SIGNAL alignment fault mode, no siginfo structure is
passed to userspace.
POSIX specifies how siginfo_t should be populated for alignment
faults, so this patch does just that:
* si_signo = SIGBUS
* si_code = BUS_ADRALN
* si_addr = misaligned data address at which access was attempted
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Kirill A. Shutemov <kirill@shutemov.name>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Currently, it's possible to set the kernel to ignore alignment
faults when changing the alignment fault handling mode at runtime
via /proc/sys/alignment, even though this is undesirable on ARMv6
and above, where it can result in infinite spins where an un-fixed-
up instruction repeatedly faults.
In addition, the kernel clobbers any alignment mode specified on
the command-line if running on ARMv6 or above.
This patch factors out the necessary safety check into a couple of
new helper functions, and checks and modifies the fault handling
mode as appropriate on boot and on writes to /proc/cpu/alignment.
Prior to ARMv6, the behaviour is unchanged.
For ARMv6 and above, the behaviour changes as follows:
* Attempting to ignore faults on ARMv6 results in the mode being
forced to UM_FIXUP instead. A warning is printed if this
happened as a result of a write to /proc/cpu/alignment. The
user's UM_WARN bit (if present) is still honoured.
* An alignment= argument from the kernel command-line is now
honoured, except that the kernel will modify the specified mode
as described above. This is allows modes such as UM_SIGNAL and
UM_WARN to be active immediately from boot, which is useful for
debugging purposes.
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>
poison_init_mem() used a loop of:
while ((count = count - 4))
which has 2 problems - an off by one error so that we do one less word
than we should, and the other is that if count == 0 then we loop forever
and poison too much. On a platform with HAVE_TCM=y but nothing in the
TCM's, this caused corruption and the platform failed to boot.
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The file mm/proc-arm946.S contains a typo and is missing a structure
member in __arm946_proc_info. The former prevents compilation
and the latter causes problems during boot. It is likely this
file was manually copied from a similar file and not tested, then
later updates to the *_proc_info structures missed this file.
This patch will apply (with offset) with or without the
recent macro unification work that has been done in this directory.
This was verified against linux-next/stable last week.
See arm-linux-kernel thread:
http://lists.arm.linux.org.uk/lurker/message/20110718.103237.0106d468.en.html
Signed-off-by: Brian S. Julin <bri@abrij.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* 'next/cross-platform' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/linux-arm-soc:
ARM: Consolidate the clkdev header files
ARM: set vga memory base at run-time
ARM: convert PCI defines to variables
ARM: pci: make pcibios_assign_all_busses use pci_has_flag
ARM: remove unnecessary mach/hardware.h includes
pci: move microblaze and powerpc pci flag functions into asm-generic
powerpc: rename ppc_pci_*_flags to pci_*_flags
Fix up conflicts in arch/microblaze/include/asm/pci-bridge.h
* 'next/soc' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/linux-arm-soc:
MAINTAINERS: add maintainer of CSR SiRFprimaII machine
ARM: CSR: initializing L2 cache
ARM: CSR: mapping early DEBUG_LL uart
ARM: CSR: Adding CSR SiRFprimaII board support
OMAP4: clocks: Update the clock tree with 4460 clock nodes
OMAP4: PRCM: OMAP4460 specific PRM and CM register bitshifts
OMAP4: ID: add omap_has_feature for max freq supported
OMAP: ID: introduce chip detection for OMAP4460
ARM: Xilinx: merge board file into main platform code
ARM: Xilinx: Adding Xilinx board support
Fix up conflicts in arch/arm/mach-omap2/cm-regbits-44xx.h
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (237 commits)
ARM: 7004/1: fix traps.h compile warnings
ARM: 6998/2: kernel: use proper memory barriers for bitops
ARM: 6997/1: ep93xx: increase NR_BANKS to 16 for support of 128MB RAM
ARM: Fix build errors caused by adding generic macros
ARM: CPU hotplug: ensure we migrate all IRQs off a downed CPU
ARM: CPU hotplug: pass in proper affinity mask on IRQ migration
ARM: GIC: avoid routing interrupts to offline CPUs
ARM: CPU hotplug: fix abuse of irqdesc->node
ARM: 6981/2: mmci: adjust calculation of f_min
ARM: 7000/1: LPAE: Use long long printk format for displaying the pud
ARM: 6999/1: head, zImage: Always Enter the kernel in ARM state
ARM: btc: avoid invalidating the branch target cache on kernel TLB maintanence
ARM: ARM_DMA_ZONE_SIZE is no more
ARM: mach-shark: move ARM_DMA_ZONE_SIZE to mdesc->dma_zone_size
ARM: mach-sa1100: move ARM_DMA_ZONE_SIZE to mdesc->dma_zone_size
ARM: mach-realview: move from ARM_DMA_ZONE_SIZE to mdesc->dma_zone_size
ARM: mach-pxa: move from ARM_DMA_ZONE_SIZE to mdesc->dma_zone_size
ARM: mach-ixp4xx: move from ARM_DMA_ZONE_SIZE to mdesc->dma_zone_size
ARM: mach-h720x: move from ARM_DMA_ZONE_SIZE to mdesc->dma_zone_size
ARM: mach-davinci: move from ARM_DMA_ZONE_SIZE to mdesc->dma_zone_size
...
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (123 commits)
perf: Remove the nmi parameter from the oprofile_perf backend
x86, perf: Make copy_from_user_nmi() a library function
perf: Remove perf_event_attr::type check
x86, perf: P4 PMU - Fix typos in comments and style cleanup
perf tools: Make test use the preset debugfs path
perf tools: Add automated tests for events parsing
perf tools: De-opt the parse_events function
perf script: Fix display of IP address for non-callchain path
perf tools: Fix endian conversion reading event attr from file header
perf tools: Add missing 'node' alias to the hw_cache[] array
perf probe: Support adding probes on offline kernel modules
perf probe: Add probed module in front of function
perf probe: Introduce debuginfo to encapsulate dwarf information
perf-probe: Move dwarf library routines to dwarf-aux.{c, h}
perf probe: Remove redundant dwarf functions
perf probe: Move strtailcmp to string.c
perf probe: Rename DIE_FIND_CB_FOUND to DIE_FIND_CB_END
tracing/kprobe: Update symbol reference when loading module
tracing/kprobes: Support module init function probing
kprobes: Return -ENOENT if probe point doesn't exist
...
Commit 66a625a (ARM: mm: proc-macros: Add generic proc/cache/tlb struct
definition macros) introduced build errors when PM_SLEEP is not enabled.
The per-CPU do_suspend/do_resume functions are defined via the
preprocessor to constant 0. However, the macros which use these were
converted to assembly, resulting in undefined references to these
functions. Fix that by moving the ! ifdef section into proc-macros.S
and deleting it from all effected proc-*.S files.
Acked-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Currently using just long but this is not enough for the LPAE format
(64-bit entries).
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Kernel space needs very little in the way of BTC maintanence as most
mappings which are created and destroyed are non-executable, and so
could never enter the instruction stream.
The case which does warrant BTC maintanence is when a module is loaded.
This creates a new executable mapping, but at that point the pages have
not been initialized with code and data, so at that point they contain
unpredictable information. Invalidating the BTC at this stage serves
little useful purpose.
Before we execute module code, we call flush_icache_range(), which deals
with the BTC maintanence requirements. This ensures that we have a BTC
maintanence operation before we execute code via the newly created
mapping.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Having this value defined at compile time prevents multiple machines with
conflicting definitions to coexist. Move it to a variable in preparation
for having a per machine value selected at run time. This is relevant
only when CONFIG_ZONE_DMA is selected.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Convert the incorrectly named PCIMEM_BASE to a variable called vga_base.
This removes the dependency on mach/hardware.h.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Convert PCIBIOS_MIN_IO and PCIBIOS_MIN_MEM to variables to allow
multi-platform builds. This also removes the requirement for a platform to
have a mach/hardware.h.
The default values for i/o and mem are 0x1000 and 0x01000000, respectively.
Per Arnd Bergmann, other values are likely to be incorrect, but this commit
does not try to address that issue.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Convert pcibios_assign_all_busses from a define to inline so platforms can
control this setting.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Remove some includes of mach/hardware.h which are not needed. hardware.h
will be removed completely for tegra and cns3xxx in follow on patch.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
ISA_DMA_THRESHOLD has been unused by non-arch code, so lets now get
rid of it from ARM by replacing it with arm_dma_zone_mask. Move
dma_supported() and dma_set_mask() out of line, and have
dma_supported() check this new variable instead.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
SiRFprimaII is the latest generation application processor from CSR’s
Multifunction SoC product family. Designed around an ARM cortex A9 core,
high-speed memory bus, advanced 3D accelerator and full-HD multi-format
video decoder, SiRFprimaII is able to meet the needs of complicated
applications for modern multifunction devices that require heavy concurrent
applications and fluid user experience. Integrated with GPS baseband,
analog and PMU, this new platform is designed to provide a cost effective
solution for Automotive and Consumer markets.
This patch adds the basic support for this SoC and EVB board based on device
tree. It is following the ZYNQ of Xilinx in some degree.
Signed-off-by: Binghua Duan <Binghua.Duan@csr.com>
Signed-off-by: Rongjun Ying <Rongjun.Ying@csr.com>
Signed-off-by: Zhiwu Song <Zhiwu.Song@csr.com>
Signed-off-by: Yuping Luo <Yuping.Luo@csr.com>
Signed-off-by: Bin Shi <Bin.Shi@csr.com>
Signed-off-by: Huayi Li <Huayi.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Originally introduced to maintain coherency between icache and dcache
in v6 nonaliasing mode. This is now handled by __sync_icache_dcache since
c0177800, therefore unnecessary in this function.
Signed-off-by: Heechul Yun <heechul@illinois.edu>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Poisoning __init marked memory can be useful when tracking down
obscure memory corruption bugs. Therefore, poison init memory
with 0xe7fddef0 to catch bugs earlier. The poison value is an
undefined instruction in ARM mode and branch to an undefined
instruction in Thumb mode.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Place the init sections between the text and data sections. This
means all code is grouped together at the beginning of the kernel
image, and all data is at the end of the image. This avoids problems
with the 24-bit branch instruction relocations becoming invalid with
large initramfs images.
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Tested-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch adds simple definitions of cpu_reset for ARMv6 and ARMv7
cores, which disable the MMU via the SCTLR.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Multicore implementations of the Cortex-A15 require bit 6 of the
auxiliary control register to be set in order for cache and TLB
maintenance operations to be broadcast between CPUs.
This patch adds a new proc_info structure for Cortex-A15, which enables
the SMP bit during setup and includes the new HWCAP for integer
division.
Signed-off-by: Will Deacon <will.deacon@arm.com>
This patch adds processor info for ARM Ltd. Cortex A5,
which has SCU initialisation procedure identical to A9.
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
As most of the proc info content is common across all v7
processors, this patch converts existing A9 and generic v7
descriptions into a macro (allowing extra flags in future).
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
CNS3xxx SOCs have L310-compatible cache controller, so let's use it.
With this patch benchmarking with 'gzip' shows that performance is
doubled, and I'm still able to boot full-fledged userland over NFS
(using PCIe NIC), so the support should be pretty robust.
p.s. While CNS3xxx reports that it has PL310, it still needs to wait
on cache line operations, so we should not select 'CACHE_PL310',
which is a micro-optimization that removes these waits for v7 CPUs.
Someday we'd better rename CACHE_PL310 Kconfig option into
NO_CACHE_WAIT or something less ambiguous.
Signed-off-by: Anton Vorontsov <avorontsov@mvista.com>
Without this patch, xscale_80200_A0_A1 is missing the
icache_flush_all entry, which would result in the wrong functions
being called at run-time.
This patch re-uses xscale_icache_flush_all for
xscale_80200_A0_A1_cache_fns.
Signed-off-by: Dave Martin <dave.martin@linaro.org>
This patch also defines a suitable flush_icache_all implementation
which would otherwise be missing, resulting in a link failure.
Thanks to Nicolas Pitre for suggesting the code for this.
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
This patch adds some generic macros to reduce boilerplate when
declaring certain common structures in arch/arm/mm/*.S
Thanks to Russell King for outlining what the
define_processor_functions macro could look like.
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
The l2x0_disable function attempts to writel with the l2x0_lock held.
This results in deadlock when the writel contains an outer_sync call
for the platform since the l2x0_lock is already held by the disable
function. A further problem is that disabling the L2 without flushing it
first can lead to the spin_lock operation becoming visible after the
spin_unlock, causing any subsequent L2 maintenance to deadlock.
This patch replaces the writel with a call to writel_relaxed in the
disabling code and adds a flush before disabling in the control
register, preventing livelock from occurring.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Ensure that the meminfo array is sanity checked before we pass the
memory to memblock. This helps to ensure that memblock and meminfo
agree on the dimensions of memory, especially when more memory is
passed than the kernel can deal with.
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Now that we pass r2 into these helper functions as the pointer to
pt_regs, use r2 as the base of the registers on the stack rather
than using the stack pointer directly.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tail-call the main C data abort handler code from the per-CPU helper
code. Update the comments in the code wrt the new calling and return
register state.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This allows us to pass the pt_regs pointer in to these functions
ready for tail-calling the abort handler.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tail-call the main C prefetch abort handler code from the per-CPU
helper code. Also note that the helper function becomes ABI
compliant in terms of the registers preserved.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Avoid enabling interrupts if the parent context had interrupts enabled
in the abort handler assembly code, and move this into the breakpoint/
page/alignment fault handlers instead.
This gets rid of some special-casing for the breakpoint fault handlers
from the low level abort handler path.
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The nmi parameter indicated if we could do wakeups from the current
context, if not, we would set some state and self-IPI and let the
resulting interrupt do the wakeup.
For the various event classes:
- hardware: nmi=0; PMI is in fact an NMI or we run irq_work_run from
the PMI-tail (ARM etc.)
- tracepoint: nmi=0; since tracepoint could be from NMI context.
- software: nmi=[0,1]; some, like the schedule thing cannot
perform wakeups, and hence need 0.
As one can see, there is very little nmi=1 usage, and the down-side of
not using it is that on some platforms some software events can have a
jiffy delay in wakeup (when arch_irq_work_raise isn't implemented).
The up-side however is that we can remove the nmi parameter and save a
bunch of conditionals in fast paths.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Michael Cree <mcree@orcon.net.nz>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Eric B Munson <emunson@mgebm.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Don Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/n/tip-agjev8eu666tvknpb3iaj0fg@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This avoids unnecessary instructions for CPUs which implement the IFAR
(instruction fault address register).
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We can test bits 27:25 and 20 of the instruction at the same time;
there's no need to separate out the check of bit 20.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Require all callers of abort macros to specify the registers to be
used. This improves the documentation at the callsites as to which
registers are being used by this assembly code.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
cpu_proc_init() does processor specific initialization, which we do
at boot time. We have been omitting to do this on resume, which
causes some of this initialization to be skipped. We've also been
skipping this on SMP initialization too.
Ensure that cpu_proc_init() is always called appropriately by
moving it into cpu_init(), and move cpu_init() to a more appropriate
point in the boot initialization.
Tested-by: Kevin Hilman <khilman@ti.com>
Acked-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Ensure that the TLS register is saved and restored over a suspend
cycle, so that userspace programs don't see a corrupted TLS value.
Tested-by: Kevin Hilman <khilman@ti.com>
Acked-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add the missing suspend/resume pointers for the suspend code. This
is needed when building for multiple CPUs.
Tested-by: Kevin Hilman <khilman@ti.com>
Acked-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The 1st board support is minimal to get a system up and running
on the Xilinx platform.
This platform reuses the clock implementation from plat-versatile, and
it depends entirely on CONFIG_OF support. There is only one board
support file which obtains all device information from a device tree
dtb file which is passed to the kernel at boot time.
Signed-off-by: John Linn <john.linn@xilinx.com>
We can't cope with initrds outside of memory, so check that the
initrd is within some declared memory to the kernel before using
it. Otherwise we're likely to OOPS during boot.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This reverts commit 45b95235b0.
Will Deacon reports that:
In 52af9c6c ("ARM: 6943/1: mm: use TTBR1 instead of reserved context ID")
I updated the ASID rollover code to use only the kernel page tables
whilst updating the ASID.
Unfortunately, the code to restore the user page tables was part of a
later patch which isn't yet in mainline, so this leaves the code
quite broken.
We're also in the process of eliminating __ARCH_WANT_INTERRUPTS_ON_CTXSW
from ARM, so lets revert these until we can properly sort out what we're
doing with the context switching.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Russell King