Add CONFIG_VIRTUALIZATION to the SH architecture
and include the virtio code there. Used to enable
the virtio drivers under QEMU.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The UP dependency was inherited from ARM, which seems to have run in to
it due to the stacktrace code not being available for SMP in certain
cases, as we don't have this particular limitation there is no specific
need to block on the SMP dependency.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This wires up CPU hotplug for SH-X3 SMP CPUs. Presently only secondary
cores can be hotplugged given that the boot CPU has to contend with the
broadcast timer. When real local timers are implemented this restriction
can be lifted.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This provides a cache of the secondary CPUs idle loop for the cases where
hotplug simply enters a low power state instead of resetting or powering
off the core.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
smp_store_cpu_info() is presently flagged as __init, but is called by
start_secondary() which is __cpuinit, fix it up.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This iterates over the maximum number of CPUs we plan to support and
makes sure they're all set in the present CPU map.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This converts from cpu_set() for the online map to set_cpu_online().
The two online map modifiers were the last remaining manual map
manipulation bits, with this in place everything now goes through
cpumask.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
With the platform ops migration, the definitions still need to be
included in the CONFIG_SMP=n case, so make the asm/smp.h include
explicit.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
When registering CPUs in the topology initialization ensure that all of
the present CPUs are flagged as hotpluggable.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Now that compressed image loading is possible for sdk7786, drop the
vmlinux.bin default image target and update the defconfig accordingly.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch updates the sh7751 pci code to handle io ports
correctly. The code is based on the sh7788x implementation.
Tested on a R2D-1 board with CONFIG_8139TOO_PIO=y.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Update the R2D defconfigs to bump up the maximum
number of SCIF ports on the system.
Fixes a broken serial console regression added
by cd5f107628.
Reported-by: Shin-ichiro KAWASAKI <kawasaki@juno.dti.ne.jp>
Signed-off-by: Magnus Damm <damm@opensource.se>
Tested-by: Alexandre Courbot <alex@dcl.info.waseda.ac.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
CHCR_TS_HIGH_SHIFT is defined as a shift of TS high bits in CHCR register,
relative to low bits. The TS_INDEX2VAL() macro has to take this into account.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* 'master' of master.kernel.org:/pub/scm/linux/kernel/git/mfleming/sh-2.6:
sh: Use correct mask when comparing PMB DATA array values
sh: Do not try merging two 128MB PMB mappings
sh: Fix zImage load address when CONFIG_32BIT=y
sh: Fix address to decompress at when CONFIG_32BIT=y
sh: Assembly friendly __pa and __va definitions
Lists of DMA channels and slaves are not changed, make them constant. Besides,
SH7724 channel and slave configuration of both DMA controllers is identical,
remove the extra copy of the configuration data.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
As explained in commit 1c0fe6e3bd, we want to call the architecture independent
oom killer when getting an unexplained OOM from handle_mm_fault, rather than
simply killing current.
Cc: linux-sh@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Signed-off-by: Nick Piggin <npiggin@suse.de>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Previously we were masking the PMB DATA array values with the value of
__MEMORY_START | PMB_V, which misses some PFN bits off the mask.
Signed-off-by: Matt Fleming <matt@console-pimps.org>
There is a logic error in pmb_merge() that means we will incorrectly try
to merge two 128MB PMB mappings into one mapping. However, 256MB isn't a
valid PMB map size and pmb_merge() will actually drop the second 128MB
mapping.
This patch allows my SDK7786 board to boot when configured with
CONFIG_MEMORY_SIZE=0x10000000.
Signed-off-by: Matt Fleming <matt@console-pimps.org>
We can't necessarily use the P1SEG region to access RAM when running in
32BIT mode, so use CONFIG_MEMORY_START as the base address.
Signed-off-by: Matt Fleming <matt@console-pimps.org>
When running in 32BIT mode the P1SEG region doesn't necessarily provide
a window onto RAM (it depends how the bootloader setup the PMB). The
correct location to place the decompressed kernel is the physical
address of _text.
Signed-off-by: Matt Fleming <matt@console-pimps.org>
This patch defines ___pa and ___va which return the physical and virtual
address of an address, respectively. These macros are suitable for
calling from assembly because they don't include the C casts required by
__pa and __va.
Signed-off-by: Matt Fleming <matt@console-pimps.org>
This cribs the MIPS plat_smp_ops approach for wrapping up the platform
ops. This will allow for mixing and matching different ops on the same
platform in the future.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This does a detect_cpu_and_cache_system() -> cpu_probe() rename, tidies
up the unused return value, and stuffs it under __cpuinit in preparation
for CPU hotplug.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This follows the x86 change and kills off the unthrottle stub. As the x86
change killed off the generic callback it isn't used anymore anyways.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This zeroes out the number of cache aliases in the cache info descriptors
when hardware alias avoidance is enabled. This cuts down on the amount of
flushing taken care of by common code, and also permits coherency control
to be disabled for the single CPU and 4k page size case.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Previously the struct module definition was pulled in from other headers,
but we want the reference to be explicit. Fixes up randconfig build
issues.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This enables support for the hardware synonym avoidance handling on SH-X3
CPUs for the case where dcache aliases are possible. icache handling is
retained, but we flip on broadcasting of the block invalidations due to
the lack of coherency otherwise on SMP.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This implements support for hardware-managed IRQ balancing as implemented
by SH-X3 cores (presently only hooked up for SH7786, but can probably be
carried over to other SH-X3 cores, too).
CPUs need to specify their distribution register along with the mask
definitions, as these follow the same format. Peripheral IRQs that don't
opt out of balancing will be automatically distributed at the whim of the
hardware block, while each CPU needs to verify whether it is handling the
IRQ or not, especially before clearing the mask.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Make sure that the timer IRQs and IPIs aren't enabled for IRQ balancing.
IPIs are disabled as a result of being percpu while the timers simply
disable balancing outright.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This adds support for hardware-assisted userspace irq masking for
special priority levels. Due to the SR.IMASK interactivity, only some
platforms implement this in hardware (including but not limited to
SH-4A interrupt controllers, and ARM-based SH-Mobile CPUs). Each CPU
needs to wire this up on its own, for now only SH7786 is wired up as an
example.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Presently address translation is default-enabled regardless of whether
CONFIG_MMU is set or not in the SH-4 case, this fixes it up, and also
makes the control init word a bit more readable in the process.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
While the MMUCR.URB and ITLB/UTLB differentiation works fine for all SH-4
and later TLBs, these features are absent on SH-3. This splits out
local_flush_tlb_all() in to SH-4 and PTEAEX copies while restoring the
old SH-3 one, subsequently fixing up the build.
This will probably want some further reordering and tidying in the
future, but that's out of scope at present.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Now with the lookup aliases in place there is no longer any need to
provide the clock string, kill it off for all legacy CPG CPUs.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
For the CPUs that have not yet been converted off of legacy CPG we
provide some pclk aliases in order to make driver migration easier.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This plugs in clkdev lookups for the SH7786 clocks and migrates off of
clock string usage for the TMU clocks.
Previously the TMU clocks were aliased to the peripheral clock, so this
gets the driver actually toggling the proper clocks now as well.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Export the status of the utlb and itlb entries through debugfs.
Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
For the boot, enable_mmu() is called from setup_arch() but we don't call
setup_arch() for any of the other cpus. So turn on the non-boot cpu's
mmu inside of start_secondary().
I noticed this bug on an SMP board when trying to map I/O memory
(smsc911x registers) into the kernel address space. Since the Address
Translation bit in MMUCR wasn't set, accessing the virtual address where
the smsc911x registers were supposedly mapped actually performed a
physical address access.
Signed-off-by: Matt Fleming <matt@console-pimps.org>
Cc: stable@kernel.org
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Ensure that the aux table is properly initialized, even when optional
features are missing. Without this, the FDPIC loader did not work.
Signed-off-by: Andrew Stubbs <ams@codesourcery.com>
Cc: stable@kernel.org
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Use set_cpus_allowed_ptr rather than set_cpus_allowed.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@@
expression E1,E2;
@@
- set_cpus_allowed(E1, cpumask_of_cpu(E2))
+ set_cpus_allowed_ptr(E1, cpumask_of(E2))
@@
expression E;
identifier I;
@@
- set_cpus_allowed(E, I)
+ set_cpus_allowed_ptr(E, &I)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Presently the TLB wiring code depends on MMUCR.URB for working out where
to place the wired entry, but fails to take the replacment counter in to
consideration. This fixes up the wiring logic and ensures that wired
entries remain so.
Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Create a common platform data header file for the
shdma dmaengine driver. This is done by moving
common structures from sh asm/dmaengine.h to
linux/sh_dma.h. DMA registers are also copied from
sh asm/dma-register.h to make the code architecture
independent.
The sh header file asm/dmaengine.h is still kept
with the slave id enum. This allows us to keep the
old processor specific code as is and slowly move
over to slave id enums in per-processor headers.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Move SHDMA_SLAVE_NUMBER from asm/dmaengine.h to
shdma.h. Set it to 256 to support a wide range
of processors. The amount of memory consumed by
this change is limited to 256 bits.
While at it, rename to SH_DMA_SLAVE_NUMBER to
match with the rest of the file.
Signed-off-by: Magnus Damm <damm@opensource.se>
Acked-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch replaces the sh_dmae_slave_chan_id enum
with an unsigned int. The purpose of this chainge is
to make it possible to separate the slave id enums
from the dmaengine header.
The slave id enums varies with processor model, so in
the future it makes sense to put these in the processor
specific headers together with the pinmux enums.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The parent rb_node needs to be initialized to shut up the compiler, even
though we're unlikely to ever hit this issue at run time.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
select_idle_routine() and register_sh_pmu() both needed their annotations
fixed up to silence section mismatch warnings.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
set_pmb_entry() is now only used by a function that is wrapped in #ifdef
CONFIG_PM, so wrap set_pmb_entry() in CONFIG_PM too.
Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Setting the TI in MMUCR causes all the TLB bits in MMUCR to be
cleared. Unfortunately, the TLB wired bits are also cleared when setting
the TI bit, causing any wired TLB entries to become unwired.
Use local_flush_tlb_all() which implements TLB flushing in a safer
manner by using the memory-mapped TLB registers. As each CPU has its own
PMB the modifications in pmb_init() only affect the local CPU, so only
flush the local CPU's TLB.
Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
flush_tlb_page() can be used to flush TLB entries that map executable
pages. Therefore, we need to ensure that the ITLB is also flushed in
local_flush_tlb_page().
Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
interruptible_sleep_on() is referenced for use in the mid_sched macro
which is not used anywhere. Remove reference and macro as well as the
comment which appears to belong with them.
Signed-off-by: Andreas Bombe <aeb@debian.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
i2c_put_adapter is needed after i2c_get_adapter
Signed-off-by: Kuninori Morimoto <morimoto.kuninori@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6:
serial: sh-sci: remove duplicated #include
sh: Export uncached helper symbols.
sh: Fix up NUMA build for 29-bit.
serial: sh-sci: Fix build failure for non-sh architectures.
sh: Fix up uncached offset for legacy 29-bit mode.
sh: Support CPU affinity masks for INTC controllers.
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (35 commits)
perf: Fix unexported generic perf_arch_fetch_caller_regs
perf record: Don't try to find buildids in a zero sized file
perf: export perf_trace_regs and perf_arch_fetch_caller_regs
perf, x86: Fix hw_perf_enable() event assignment
perf, ppc: Fix compile error due to new cpu notifiers
perf: Make the install relative to DESTDIR if specified
kprobes: Calculate the index correctly when freeing the out-of-line execution slot
perf tools: Fix sparse CPU numbering related bugs
perf_event: Fix oops triggered by cpu offline/online
perf: Drop the obsolete profile naming for trace events
perf: Take a hot regs snapshot for trace events
perf: Introduce new perf_fetch_caller_regs() for hot regs snapshot
perf/x86-64: Use frame pointer to walk on irq and process stacks
lockdep: Move lock events under lockdep recursion protection
perf report: Print the map table just after samples for which no map was found
perf report: Add multiple event support
perf session: Change perf_session post processing functions to take histogram tree
perf session: Add storage for seperating event types in report
perf session: Change add_hist_entry to take the tree root instead of session
perf record: Add ID and to recorded event data when recording multiple events
...
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (56 commits)
doc: fix typo in comment explaining rb_tree usage
Remove fs/ntfs/ChangeLog
doc: fix console doc typo
doc: cpuset: Update the cpuset flag file
Fix of spelling in arch/sparc/kernel/leon_kernel.c no longer needed
Remove drivers/parport/ChangeLog
Remove drivers/char/ChangeLog
doc: typo - Table 1-2 should refer to "status", not "statm"
tree-wide: fix typos "ass?o[sc]iac?te" -> "associate" in comments
No need to patch AMD-provided drivers/gpu/drm/radeon/atombios.h
devres/irq: Fix devm_irq_match comment
Remove reference to kthread_create_on_cpu
tree-wide: Assorted spelling fixes
tree-wide: fix 'lenght' typo in comments and code
drm/kms: fix spelling in error message
doc: capitalization and other minor fixes in pnp doc
devres: typo fix s/dev/devm/
Remove redundant trailing semicolons from macros
fix typo "definetly" -> "definitely" in comment
tree-wide: s/widht/width/g typo in comments
...
Fix trivial conflict in Documentation/laptops/00-INDEX
All the architectures properly set NEED_DMA_MAP_STATE now so we can safely
add linux/pci-dma.h to linux/pci.h and remove the linux/pci-dma.h
inclusion in arch's asm/pci.h
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
While in theory user_enable_single_step/user_disable_single_step/
user_enable_blockstep could also be provided as an inline or macro there's
no good reason to do so, and having the prototype in one places keeps code
size and confusion down.
Roland said:
The original thought there was that user_enable_single_step() et al
might well be only an instruction or three on a sane machine (as if we
have any of those!), and since there is only one call site inlining
would be beneficial. But I agree that there is no strong reason to care
about inlining it.
As to the arch changes, there is only one thought I'd add to the
record. It was always my thinking that for an arch where
PTRACE_SINGLESTEP does text-modifying breakpoint insertion,
user_enable_single_step() should not be provided. That is,
arch_has_single_step()=>true means that there is an arch facility with
"pure" semantics that does not have any unexpected side effects.
Inserting a breakpoint might do very unexpected strange things in
multi-threaded situations. Aside from that, it is a peculiar side
effect that user_{enable,disable}_single_step() should cause COW
de-sharing of text pages and so forth. For PTRACE_SINGLESTEP, all these
peculiarities are the status quo ante for that arch, so having
arch_ptrace() itself do those is one thing. But for building other
things in the future, it is nicer to have a uniform "pure" semantics
that arch-independent code can expect.
OTOH, all such arch issues are really up to the arch maintainer. As
of today, there is nothing but ptrace using user_enable_single_step() et
al so it's a distinction without a practical difference. If/when there
are other facilities that use user_enable_single_step() and might care,
the affected arch's can revisit the question when someone cares about
the quality of the arch support for said new facility.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add generic implementations of the old and really old uname system calls.
Note that sh only implements sys_olduname but not sys_oldolduname, but I'm
not going to bother with another ifdef for that special case.
m32r implemented an old uname but never wired it up, so kill it, too.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a generic implementation of the ipc demultiplexer syscall. Except for
s390 and sparc64 all implementations of the sys_ipc are nearly identical.
There are slight differences in the types of the parameters, where mips
and powerpc as the only 64-bit architectures with sys_ipc use unsigned
long for the "third" argument as it gets casted to a pointer later, while
it traditionally is an "int" like most other paramters. frv goes even
further and uses unsigned long for all parameters execept for "ptr" which
is a pointer type everywhere. The change from int to unsigned long for
"third" and back to "int" for the others on frv should be fine due to the
in-register calling conventions for syscalls (we already had a similar
issue with the generic sys_ptrace), but I'd prefer to have the arch
maintainers looks over this in details.
Except for that h8300, m68k and m68knommu lack an impplementation of the
semtimedop sub call which this patch adds, and various architectures have
gets used - at least on i386 it seems superflous as the compat code on
x86-64 and ia64 doesn't even bother to implement it.
[akpm@linux-foundation.org: add sys_ipc to sys_ni.c]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Reviewed-by: H. Peter Anvin <hpa@zytor.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Kyle McMartin <kyle@mcmartin.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove the hw_perf_event_*() hotplug hooks in favour of per PMU hotplug
notifiers. This has the advantage of reducing the static weak interface
as well as exposing all hotplug actions to the PMU.
Use this to fix x86 hotplug usage where we did things in ONLINE which
should have been done in UP_PREPARE or STARTING.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
LKML-Reference: <20100305154128.736225361@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This fixes up some of the I/D/F clock ambiguity in the sh-sci driver.
The interface clock in most cases just wraps back to the peripheral
clock, while the function clock wraps in to the MSTP bits. As the logic
was somewhat inverted, this cleans that up, and also enables all CPUs
with SCI MSTP bits to match function clocks through clkdev lookup.
As a result, this gets rid of the clk string abuse on the sh side, and
the clock string will be killed off once the ARM code has had a chance to
sync up. This also enables MSTP gating on CPUs like 7786 which had never
wired it up before. Impacted CPUs are primarily all SH-Mobiles, SH7785,
and SH7786.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
pmb_bolt_mapping() is undefined on 29-bit builds, so provide a stub.
This fixes up the NUMA build on platforms lacking PMB support.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Now that dev_name() can be used early, we no longer require a static
string. Kill off all of the superfluous timer names.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
early platform devices and the like may need to set up clock aliases,
which require an allocation at a time well before the slab allocators
are available. The clock framework comes up after bootmem, so using
bootmem as a fallback should be sufficient.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This rolls in the remainder of the clkdev API bits from the ARM tree.
This can more or less be used verbatim, so we just copy it over and nuke
our local version.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The uncached_start was being set up properly for 32-bit but managed to
break 29-bit in the process, fix it up.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Constify struct sysfs_ops.
This is part of the ops structure constification
effort started by Arjan van de Ven et al.
Benefits of this constification:
* prevents modification of data that is shared
(referenced) by many other structure instances
at runtime
* detects/prevents accidental (but not intentional)
modification attempts on archs that enforce
read-only kernel data at runtime
* potentially better optimized code as the compiler
can assume that the const data cannot be changed
* the compiler/linker move const data into .rodata
and therefore exclude them from false sharing
Signed-off-by: Emese Revfy <re.emese@gmail.com>
Acked-by: David Teigland <teigland@redhat.com>
Acked-by: Matt Domsch <Matt_Domsch@dell.com>
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Acked-by: Hans J. Koch <hjk@linutronix.de>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch converts the sh architecture to use the generic
read_persistent_clock and update_persistent_clock interfaces, reducing
the amount of arch specific code we have to maintain, and allowing for
further cleanups in the future.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
... so the "sh_debugfs_root" is already available. Previously it
wasn't and in result its path was "/sys/kernel/debug/pmb" instead of
"/sys/kernel/debug/sh/pmb".
Signed-off-by: Pawel Moll <pawel.moll@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
flush_cache_all() uses broadcast IPIs, so we can't wrap in to that when
IRQs are disabled. The local cache flush manages to do what we need here
anyways, so just switch to that.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Presently we run in to issues with the MMU resetting the CPU when
variable sized mappings are employed. This takes a slightly more
aggressive approach to keeping the TLB and cache state sane before
establishing the mappings in order to cut down on races observed on
SMP configurations.
At the same time, we bump the VMA range up to the 0xb000...0xc000 range,
as there still seems to be some undocumented behaviour in setting up
variable mappings in the 0xa000...0xb000 range, resulting in reset by the
TLB.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
In the case of NUMA emulation when in range PPNs are being used for
secondary nodes, we need to make sure that the PMB has a mapping for it
before setting up the pgdat. This prevents the MMU from resetting.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
When entries are being bolted unconditionally it's possible that the boot
loader has established mappings that are within range that we don't want
to clobber. Perform some basic validation to ensure that the new mapping
is out of range before allowing the entry setup to take place.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This moves the pmb_remap_caller() mapping logic out in to
pmb_bolt_mapping(), which enables us to establish fixed mappings in
places such as the NUMA code.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This plugs in an early_param for permitting transparent PMB-backed
ioremapping to be enabled/disabled. For the time being, we use a
default-disabled policy.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This implements a fairly significant overhaul of the dynamic PMB mapping
code. The primary change here is that the PMB gets its own VMA that
follows the uncached mapping and we attempt to be a bit more intelligent
with dynamic sizing, multi-entry mapping, and so forth.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch extends the .device_terminate_all() method of the shdma driver
to return number of bytes transfered in the current descriptor.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
DMA CHCR register layout is equal on sh7722 and sh7724, reuse definitions.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Separate SH DMA headers into ones, commonly used by both drivers, and ones,
specific to each of them. This will make the future development of the
dmaengine driver easier.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The shdma dmaengine driver currently uses numerous macros to support various
platforms, selected by ifdef's. Convert it to use platform device resources and
lists of channel descriptors to specify register locations, interrupt numbers
and other system-specific configuration variants. Unavoidably, we have to
simultaneously convert all shdma users to provide those resources.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Configure SIU port B pins and register the WM8978 audio codec.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch is required to use the SIU ASoC driver on sh7722 systems.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6: (252 commits)
ASoC: Check progress when reporting periods from i.MX FIQ handler
ASoC: Remove a unused variables from i.MX FIQ runtime data
ALSA: hda - Add/fix ALC269 FSC and Quanta models
ALSA: hda - Add ALC670 codec support
OMAP4: PMIC: Add support for twl6030 codec
ALSA: hda - remove unnecessary msleep on power state transitions
usb/gadget/{f_audio,gmidi}.c: follow recent changes in audio.h
ASoC: fsi: Modify over/under run error settlement
ASoC: OMAP4: Add McPDM platform driver
ASoC: OMAP4: Add support for McPDM
ASoC: OMAP: data_type and sync_mode configurable in audio dma
ALSA: hda - Add missing description in HD-Audio-Models.txt
ALSA: add support for Macbook Air 2,1 internal speaker
ALSA: usbaudio: consolidate header files
ALSA: usbmixer: bail out early when parsing audio class v2 descriptors
ALSA: usbaudio: implement basic set of class v2.0 parser
ALSA: usbaudio: introduce new types for audio class v2
ALSA: usbaudio: parse USB descriptors with structs
ALSA: hda - enable snoop for Intel Cougar Point
ALSA: hda - Remove identical definitions for macmini3 model
...
Since <linux/spinlock.h> already includes <linux/rwlock.h>, and the
latter file will warn about not having included the former file
anyway, there is no value in including rwlock.h explicitly.
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
arch/sh/boot/compressed/cache.c:8: WARNING: space prohibited between function name and open parenthesis '('
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
arch/sh/lib/libgcc.h:21: ERROR: open brace '{' following union go on the same line
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This follows the x86 change 84d7109267
("hw-breakpoints: Accept breakpoints on NULL address") and restores the
previous expected ptrace behaviour.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (28 commits)
ftrace: Add function names to dangling } in function graph tracer
tracing: Simplify memory recycle of trace_define_field
tracing: Remove unnecessary variable in print_graph_return
tracing: Fix typo of info text in trace_kprobe.c
tracing: Fix typo in prof_sysexit_enable()
tracing: Remove CONFIG_TRACE_POWER from kernel config
tracing: Fix ftrace_event_call alignment for use with gcc 4.5
ftrace: Remove memory barriers from NMI code when not needed
tracing/kprobes: Add short documentation for HAVE_REGS_AND_STACK_ACCESS_API
s390: Add pt_regs register and stack access API
tracing/kprobes: Make Kconfig dependencies generic
tracing: Unify arch_syscall_addr() implementations
tracing: Add notrace to TRACE_EVENT implementation functions
ftrace: Allow to remove a single function from function graph filter
tracing: Add correct/incorrect to sort keys for branch annotation output
tracing: Simplify test for function_graph tracing start point
tracing: Drop the tr check from the graph tracing path
tracing: Add stack dump to trace_printk if stacktrace option is set
tracing: Use appropriate perl constructs in recordmcount.pl
tracing: optimize recordmcount.pl for offsets-handling
...
* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6: (362 commits)
V4L-DVB: cx88-dvb: remove extra attribution for core
V4L/DVB: v4l: soc_camera: fix bound checking of mbus_fmt[] index
V4L/DVB: Add support for SMT7020 to cx88
V4L/DVB: radio-si470x: Use UTF-8 encoding on a comment
V4L/DVB: MAINTAINERS: Telegent tlg2300 section fix
V4L/DVB: gspca_stv06xx: Add support for camera button
V4L/DVB: gspca_ov519: add support for the button on ov511 based cams
V4L/DVB: gspca_ov519: Add support for the button on ov518 based cams
V4L/DVB: gspca_ov519: add support for the button on ov519 based cams
V4L/DVB: gspca_main: Fix a compile error when CONFIG_INPUT is not set
V4L/DVB: gspca_main: some input error handling fixes
V4L/DVB: gspca_main: Allow use of input device creation code for non int. inputs
V4L/DVB: gspca_pac7302: much improved exposure control
V4L/DVB: gspca_sonixb: Make sonixb driver handle pas106 and pas202 cameras
V4L/DVB: gspca_sonixb: pas106: fixup bright ctrl and add gain and exposure ctrls
V4L/DVB: Documentation: gspca.txt: update known mr97310a cams
V4L/DVB: gspca_mr97310a: add support for the Sakar 1638x CyberPix
V4L/DVB: gscpa_sonixb: limit ov7630 max framerate at 640x480
V4L/DVB: gspca_sonixb: pas202: fixup brightness ctrl and add gain and exposure ctrls
V4L/DVB: gscpa_sonixb: Differentiate between sensors with a coarse and fine expo ctrl
...
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/xfs-vipt:
xfs: fix xfs to work with Virtually Indexed architectures
sh: add mm API for DMA to vmalloc/vmap areas
arm: add mm API for DMA to vmalloc/vmap areas
parisc: add mm API for DMA to vmalloc/vmap areas
mm: add coherence API for DMA to vmalloc/vmap areas
* git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6: (187 commits)
sh: remove dead LED code for migo-r and ms7724se
sh: ecovec build fix for CONFIG_I2C=n
sh: ecovec r-standby support
sh: ms7724se r-standby support
sh: SH-Mobile R-standby register save/restore
clocksource: Fix up a registration/IRQ race in the sh drivers.
sh: ms7724: modify scan_timing for KEYSC
sh: ms7724: Add sh_sir support
sh: mach-ecovec24: Add sh_sir support
sh: wire up SET/GET_UNALIGN_CTL.
sh: allow alignment fault mode to be configured at kernel boot.
sh: sh7724: Update FSI/SPU2 clock
sh: always enable sh7724 vpu_clk and set to 166MHz on Ecovec
sh: add sh7724 kick callback to clk_div4_table
sh: introduce struct clk_div4_table
sh: clock-cpg div4 set_rate() shift fix
sh: Turn on speculative return for SH7785 and SH7786
sh: Merge legacy and dynamic PMB modes.
sh: Use uncached I/O helpers in PMB setup.
sh: Provide uncached I/O helpers.
...
This patch removes "buswidth" struct member, and sets the default buswidth
to the natively supported 10 bit. You can select 8 bit buswidth by new flag.
This patch also modify ap325rxa/migor setup.c
Signed-off-by: Kuninori Morimoto <morimoto.kuninori@renesas.com>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
CONFIG_PM is always set on SH-Mobile these days so
get rid of the unused LED setup code.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Allow building the ecovec board support code
even though I2C support is disabled.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch adds board specific r-standby resume code
for ecovec.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch adds board specific r-standby resume code
for ms7724se.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Add code to save/restore registers during
R-standby sleep on SH-Mobile processors.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
KEYSC::SCN register of SH7724 is 3bit.
Thus, scan_timing should be 0 - 7 here.
Signed-off-by: Kuninori Morimoto <morimoto.kuninori@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This hooks up the SET/GET_UNALIGN_CTL knobs cribbing the bulk of it from
the PPC and ia64 implementations. The thread flags happen to be the
logical inverse of what the global fault mode is set to, so this works
out pretty cleanly. By default the global fault mode is used, with tasks
now being able to override their own settings via prctl().
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Now that we return the new resource start position, there is no
need to update "struct resource" inside the align function.
Therefore, mark the struct resource as const.
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
As suggested by Linus, align functions should return the start
of a resource, not void. An update of "res->start" is no longer
necessary.
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
When FSI and Network (= NFS file system) were used at the same time,
the I/O of FSI was unstable. This patch updates the SPU2 clock (which
is used for FSI) to solve this issue. Special thanks to Jeremy.
Signed-off-by: Jeremy Baker <Jeremy.Baker@renesas.com>
Signed-off-by: Kuninori Morimoto <morimoto.kuninori@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Update the sh7724 processor code to always enable vpu_clk.
On the Ecovec board, set the vpu_clk to 166 Mhz.
The 166MHz setting results in a divide-by-6 setup for
vpu_clk and improves the VPU performance compared to the
power-on-reset/bootloader configuration.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch adds a ->kick() callback to clk_div4_table
and ties it into sh_clk_div4_set_rate(). A sh7724
specific kick function is also added that updates the
KICK bit whenever div4 clocks in FRQCRA and FRQCRB
have been set. Allows us to set the VPU clock.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch introduces struct clk_div4_table. The structure
will be used to keep div4 specific data, and is with this
patch replacing the struct clk_div_mult_table pointer arg
used by the sh_clk_div4_register() functions.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Make sure the div4 bitfield is shifted according
to the enable_bit value in sh_clk_div4_set_rate().
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
On VIVT ARM, when we have multiple shared mappings of the same file
in the same MM, we need to ensure that we have coherency across all
copies. We do this via make_coherent() by making the pages
uncacheable.
This used to work fine, until we allowed highmem with highpte - we
now have a page table which is mapped as required, and is not available
for modification via update_mmu_cache().
Ralf Beache suggested getting rid of the PTE value passed to
update_mmu_cache():
On MIPS update_mmu_cache() calls __update_tlb() which walks pagetables
to construct a pointer to the pte again. Passing a pte_t * is much
more elegant. Maybe we might even replace the pte argument with the
pte_t?
Ben Herrenschmidt would also like the pte pointer for PowerPC:
Passing the ptep in there is exactly what I want. I want that
-instead- of the PTE value, because I have issue on some ppc cases,
for I$/D$ coherency, where set_pte_at() may decide to mask out the
_PAGE_EXEC.
So, pass in the mapped page table pointer into update_mmu_cache(), and
remove the PTE value, updating all implementations and call sites to
suit.
Includes a fix from Stephen Rothwell:
sparc: fix fallout from update_mmu_cache API change
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This implements a bit of rework for the PMB code, which permits us to
kill off the legacy PMB mode completely. Rather than trusting the boot
loader to do the right thing, we do a quick verification of the PMB
contents to determine whether to have the kernel setup the initial
mappings or whether it needs to mangle them later on instead.
If we're booting from legacy mappings, the kernel will now take control
of them and make them match the kernel's initial mapping configuration.
This is accomplished by breaking the initialization phase out in to
multiple steps: synchronization, merging, and resizing. With the recent
rework, the synchronization code establishes page links for compound
mappings already, so we build on top of this for promoting mappings and
reclaiming unused slots.
At the same time, the changes introduced for the uncached helpers also
permit us to dynamically resize the uncached mapping without any
particular headaches. The smallest page size is more than sufficient for
mapping all of kernel text, and as we're careful not to jump to any far
off locations in the setup code the mapping can safely be resized
regardless of whether we are executing from it or not.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The PMB code is an example of something that spends an absurd amount of
time running uncached when only a couple of operations really need to be.
This switches over to the shiny new uncached helpers, permitting us to
spend far more time running cached.
Additionally, MMUCR twiddling is perfectly safe from cached space given
that it's paired with a control register barrier, so fix that up, too.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
There are lots of registers that can only be updated from the uncached
mapping, so we add some helpers for those cases in order to make it
easier to ensure that we only make the jump when it's absolutely
necessary.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
