Extract the logic for searching through the file descriptors for spu contexts
into a separate routine, coredump_next_context(), so we can use it elsewhere
in future. In the process we flatten the for loop, and move the NOSCHED test
into coredump_next_context().
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We don't want SPE programs to be able to flood the kernel log by
invoking the SPE callback handler, so don't enable DEBUG for
spu_callbacks.c by default.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Based on an original patch from Masato Noguchi
<Masato.Noguchi@jp.sony.com>.
We're currently not restoring the SPE decrementer as specified by the
CBE handbook. This change fixes our implementation to match, and makes
the function read more like the docs.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
At present, a built-in spufs will not use the spufs_calls callbacks, but
directly call sys_spu_create. This saves us an indirect branch, but
means we have duplicated functions - one for CONFIG_SPU_FS=y and one for
=m.
This change unifies the spufs syscall path, and provides access to the
spufs_calls structure through a get/put pair. At present, the only user
of the spufs_calls structure is spu_syscalls.c, but this will facilitate
adding the coredump calls later.
Everyone likes numbers, right? Here's a before/after comparison with
CONFIG_SPU_FS=y, doing spu_create(); close(); 64k times.
Before:
[jk@cell ~]$ time ./spu_create
performing 65536 spu_create calls
real 0m24.075s
user 0m0.146s
sys 0m23.925s
After:
[jk@cell ~]$ time ./spu_create
performing 65536 spu_create calls
real 0m24.777s
user 0m0.141s
sys 0m24.631s
So, we're adding around 11us per syscall, at the benefit of having
only one syscall path.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Affinity reference point location (gang->aff_ref_spu) is reset
when the whole gang is descheduled. However, the last member of
a gang can be descheduled while we are trying to schedule another
member of the gang. This was leading to a race condition, and
the code was using gang->aff_ref_spu in an unsafe manner.
By holding the gang->aff_mutex a little bit longer, and increment
gang->aff_sched_count (which controls when gang->aff_ref_spu
should be reset) a little bit earlier, the problem is fixed.
Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
According to the comment in spufs_init_isolated_loader(), the isolated
loader should be aligned on a 16 byte boundary.
ARCH_{KMALLOC,SLAB}_MINALIGN is not defined so only 8 byte alignment is
guaranteed.
This enforces alignment via __get_free_pages.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Based on an initial patch from Sebastian Siewior
<sebastian@breakpoint.cc>
spu_harvest isn't used, remove it.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
do_spu_create doesn't need the asmlinkage qualifier; remove it.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
There are a few symbols used only in one file within spufs; this change
makes them static where suitable.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The most common match semantic is an exact match based on the device node.
So provide a default implementation that does this, and hook it up if no
match routine is specified.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The majority of irq_host implementations (3 out of 4) are associated
with a device_node, and need to stash it somewhere. Rather than having
it somewhere different for each host, add an optional device_node pointer
to the irq_host structure.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The Cell BE Architecture spec states that the SPU MFC Class 0 interrupt
is edge-triggered. The current spu interrupt handler assumes this
behavior and does not clear the interrupt status.
The PS3 hypervisor visualizes all SPU interrupts as level, and on return
from the interrupt handler the hypervisor will deliver a new virtual
interrupt for any unmasked interrupts which for which the status has not
been cleared. This fix clears the interrupt status in the interrupt
handler.
Signed-off-by: Masato Noguchi <Masato.Noguchi@jp.sony.com>
Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Acked-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This fixes a major bug which was happening when a SPU thread advances
its execution right after being restored to a SPU. A potentially
outdated NPC value was being (re)written to the SPU.
So, spu_run_init, in this case, was either not doing anything relevant,
or breaking the execution of the SPU thread.
This fixes a common problem of losing a mailbox write when it was done
to a saved context.
Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
When a process writes into the inbound spu mailbox (wbox) while the
context is saved, we accidentally break the contents of the mb_stat_R
register by clearing other entries of the mailbox status register. This
can cause the user side to hang.
This change fixes the problem by only altering the appropriate bits
of the mailbox status register during a backing-store write.
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This fixes a regression introduced with 2.6.23-rc4 after on some
confusion about the device tree interfaces.
IBM QS21 device trees provide "physical-id", so we changed the code to
run on that and remain compatible with all IBM machines.
However, the Toshiba Celleb device tree provides the "unit-id" property,
which was in the Linux code, but never used in this way on IBM hardware.
Legacy device tree used the reg property for the physical id of an spe.
This patch fixes find_spu_unit_number to look for the spu id in that order.
The length is checked to avoid misinterpretation in case the attributes
unit-id or reg do not contain the id.
Signed-off-by: Christian Krafft <krafft@de.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Cc: Jeremy Kerr <jk@ozlabs.org>
The Cell Broadband Engine has a method of injecting a
system-reset-exception from an external source into the
operating system, which should trigger the regular behaviour
of entering xmon or kdump.
Unfortunately, the exception handler cannot distinguish it from
other interrupt causes by the SRR1 register, which gets used
for this on Power 6 and others.
IBM Blade servers that want to support triggering the
system reset exception using a pinhole button in the front
panel therefore use an extra register to determine the
reset cause.
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
--
Signed-off-by: Paul Mackerras <paulus@samba.org>
Legacy device tree used the reg property for the physical id of an
spe. On newer device tree layouts the reg property contains the
"correct" value in the reg attribute. So there has been intoduced the
"physical-id" on newer devicetree layouts. The id is stored by
spu_manage into the spu struct as spe_id. cbe_thermal has been
changed to use the spu->spe_id. There's no need for the thermal code
to check devicetree attributes for itself.
Signed-off-by: Christian Krafft <krafft@de.ibm.com>
Cc: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
At present, spu_create with an invalid neighbo(u)r will return -ENOSYS,
not -EBADF, but only when spufs.o is built as a module.
This change adds the appropriate errno, making the behaviour the same
as the built-in case.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Acked-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch moves affinity initialization code from spu_base.c to a
new spu_management_of_ops function (init_affinity), which is empty
in the case of PS3. This fixes a linking problem that was happening
when compiling for PS3.
Also, some small code style changes were made.
Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Acked-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch fixes affinity reference point placement, which was not being
done in some situations, after the introduction of node_allowed() calls.
The previously used parameter, 'ctx', is just the iterator of the
previous list_for_each_entry_reverse loop, and its value might be
invalid at the end of the loop. Also, the right context to seek
for information when defining the reference ctx location
_is_ the reference ctx.
Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Currently we calculate the first timeslice for every context
incorrectly - alloc_spu_context calls spu_set_timeslice before we set
ctx->prio so we always calculate the longest possible timeslice for the
lowest possible priority.
This patch makes sure to update the schedule-related fields before
calculating the timeslice and also makes sure we update the timeslice for
a non-running context when entering spu_run so a priority change affects
the context as soon as possible.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We currently initialize cbe_spu_info[].spus in both init_spu_base and
spu_sched_init. The initialise in spu_sched_init clears the SPU list,
so we end up with no physical SPUs. Because of this, the spu_run
syscall will block forever.
This change removes the unnecessary initialization in spu_sched_init.
Signed-off-by: Masato Noguchi <Masato.Noguchi@jp.sony.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
spufs.h now has two enums for the sched_flags leading to identical
values for SPU_SCHED_WAS_ACTIVE and SPU_SCHED_NOTIFY_ACTIVE. Merge
them into a single enum as they were in the IBM development tree.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix a mismerge in commit 8b6f50ef1d:
"spufs: make signal-notification files readonly for NOSCHED contexts",
where structs got duplicated.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Reading from the signal{1,2} files requires a spu_acquire_saved, so make these
files write-only for contexts created with SPU_CREATE_NOSCHED.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Acked-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This sorts out the various lists and related locks in the spu code.
In detail:
- the per-node free_spus and active_list are gone. Instead struct spu
gained an alloc_state member telling whether the spu is free or not
- the per-node spus array is now locked by a per-node mutex, which
takes over from the global spu_lock and the per-node active_mutex
- the spu_alloc* and spu_free function are gone as the state change is
now done inline in the spufs code. This allows some more sharing of
code for the affinity vs normal case and more efficient locking
- some little refactoring in the affinity code for this locking scheme
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
From: Maynard Johnson <mpjohn@us.ibm.com>
This patch updates the existing arch/powerpc/oprofile/op_model_cell.c
to add in the SPU profiling capabilities. In addition, a 'cell' subdirectory
was added to arch/powerpc/oprofile to hold Cell-specific SPU profiling code.
Exports spu_set_profile_private_kref and spu_get_profile_private_kref which
are used by OProfile to store private profile information in spufs data
structures.
Also incorporated several fixes from other patches (rrn). Check pointer
returned from kzalloc. Eliminated unnecessary cast. Better error
handling and cleanup in the related area. 64-bit unsigned long parameter
was being demoted to 32-bit unsigned int and eventually promoted back to
unsigned long.
Signed-off-by: Carl Love <carll@us.ibm.com>
Signed-off-by: Maynard Johnson <mpjohn@us.ibm.com>
Signed-off-by: Bob Nelson <rrnelson@us.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
From: Maynard Johnson <mpjohn@us.ibm.com>
This patch adds to the capability of spu_switch_event_register so that
the caller is also notified of currently active SPU tasks.
Exports spu_switch_event_register and spu_switch_event_unregister so
that OProfile can get access to the notifications provided.
Signed-off-by: Maynard Johnson <mpjohn@us.ibm.com>
Signed-off-by: Carl Love <carll@us.ibm.com>
Signed-off-by: Bob Nelson <rrnelson@us.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Sort out the locking mess in spu_base and document the current rules.
As an added benefit spu_alloc* and spu_free don't block anymore.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
This patch links spus according to their physical position using
information provided by the firmware through a special vicinity
device-tree property. This property is present in current version
of Malta firmware.
Example of vicinity properties for a node in Malta:
Node: Vicinity property contains phandles of:
spe@0 [ spe@100000 , mic-tm@50a000 ]
spe@100000 [ spe@0 , spe@200000 ]
spe@200000 [ spe@100000 , spe@300000 ]
spe@300000 [ spe@200000 , bif0@512000 ]
spe@80000 [ spe@180000 , mic-tm@50a000 ]
spe@180000 [ spe@80000 , spe@280000 ]
spe@280000 [ spe@180000 , spe@380000 ]
spe@380000 [ spe@280000 , bif0@512000 ]
Only spe@* have a vicinity property (e.g., bif0@512000 and
mic-tm@50a000 do not have it).
Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
This patch makes the scheduller honor affinity information for each
context being scheduled. If the context has no affinity information,
behaviour is unchanged. If there are affinity information, context is
schedulled to be run on the exact spu recommended by the affinity
placement algorithm.
Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
This patch provides the spu affinity placement logic for the spufs scheduler.
Each time a gang is going to be scheduled, the placement of a reference
context is defined. The placement of all other contexts with affinity from
the gang is defined based on this reference context location and on a
precomputed displacement offset.
Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
This patch adds support for additional flags at spu_create, which relate
to the establishment of affinity between contexts and contexts to memory.
A fourth, optional, parameter is supported. This parameter represent
a affinity neighbor of the context being created, and is used when defining
SPU-SPU affinity.
Affinity is represented as a doubly linked list of spu_contexts.
Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
This patch allows the use of spu affinity on QS20, whose
original FW does not provide affinity information.
This is done through two hardcoded arrays, and by reading the reg
property from each spu.
Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
This patch adds affinity data to each spu instance.
A doubly linked list is created, meant to connect the spus
in the physical order they are placed in the BE. SPUs
near to memory should be marked as having memory affinity.
Adjustments of the fields acording to FW properties is done
in separate patches, one for CPBW, one for Malta (patch for
Malta under testing).
Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Addition of a spufs-global "cbe_info" array. Each entry contains information
about one Cell/B.E. node, namelly:
* list of spus (both free and busy spus are in this list);
* list of free spus (replacing the static spu_list from spu_base.c)
* number of spus;
* number of reserved (non scheduleable) spus.
SPE affinity implementation actually requires only access to one spu per
BE node (since it implements its own pointer to walk through the other spus
of the ring) and the number of scheduleable spus (n_spus - non_sched_spus)
However having this more general structure can be useful for other
functionalities, concentrating per-cbe statistics / data.
Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
spu_sched->bitmap has MAX_PRIO(=140) width in bits.However, since
ff80a77f20, sched_find_first_bit()
only supports 100-bit bitmaps.
Thus, spu_sched->bitmap should be treated by generic find_first_bit().
Signed-off-by: Masato Noguchi <Masato.Noguchi@jp.sony.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
From: Sebastian Siewior <cbe-oss-dev@ml.breakpoint.cc>
The 'file' argument is unused in spufs_run_spu(). This change removes
it.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
The SPU decrementer should be restored after the LSCSA DMA has
completed.
Signed-off-by: Masato Noguchi <Masato.Noguchi@jp.sony.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
No need to halt the SPE decrementer at context restore step 47, it will
be done in step 7.
Signed-off-by: Masato Noguchi <Masato.Noguchi@jp.sony.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
At save step 8, the mfc control register in the CSA should be written
_only_ with Sc and Sm bits (at least MFC_CNTL[Dh] should be set to 0)
Signed-off-by: Masato Noguchi <Masato.Noguchi@jp.sony.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
The decr_status in the LSCSA is valid only in the sequence of context
restore. Thus, it's nonsense to read and/or write it through spufs.
This patch changes decr_status node to access MFC_CNTL[Ds] in the CSA.
Signed-off-by: Masato Noguchi <Masato.Noguchi@jp.sony.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
The decr_status in the LSCSA is confusedly used as two meanings:
* SPU decrementer was running
* SPU decrementer was wrapped as a result of adjust
and the code to set decr_status is missing.
This patch fixes these problems by using the decr_status argument as a
set of flags. This requires a rebuild of the shipped spu_restore code.
Signed-off-by: Masato Noguchi <Masato.Noguchi@jp.sony.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
The following steps are not needed in the SPE context save/restore
paths:
Save Step 12: save_mfc_decr()
save suspend_time to CSA (It will be done by step 14)
save ch 7 (decrementer value will be saved in LSCSA by spe-side step 10)
Restore Step 59: restore_ch_part1()
restore ch 1 (it will be done by spe-side step 15)
This change removes the unnecessary steps.
Signed-off-by: Masato Noguchi <Masato.Noguchi@jp.sony.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Based on a fix from Masato Noguchi <Masato.Noguchi@jp.sony.com>.
Remove the (incorrect) array size declarations in the spufs channel
arrays, and use ARRAY_SIZE rather than hardcoded values.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Currently a process is removed from the physical spu when spu_acquire_saved
is saved but never put back. This patch adds a new spu_release_saved
that is to be paired with spu_acquire_saved and put the process back if
it has been in RUNNABLE state before.
Niether Jeremy not be are entirely happy about this exact patch because
it adds another spu_activate call outside of the owner thread, but I
feel this is the best short-term fix we can come up with.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
This patch exports per-context statistics in spufs as long as spu
statistics in sysfs.
It was formed by merging:
"spufs: add spu stats in sysfs" From: Christoph Hellwig
"spufs: add stat file to spufs" From: Christoph Hellwig
"spufs: fix libassist accounting" From: Jeremy Kerr
"spusched: fix spu utilization statistics" From: Luke Browning
And some adjustments by myself, after suggestions on cbe-oss-dev.
Having separate patches was making the review process harder
than it should, as we end up integrating spus and ctx statistics
accounting much more than it was on the first implementation.
Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
In 6cbf93960e64f313f6e247cbca7afaa50e3ee2c we added a WARN_ON for
calling spu_deactivate on contexts created with the SPU_CREATE_NOSCHED
flag. However, all NOSCHED contexts will need to be deactivated when
the context is destroyed, so this gives a spurious warning when any
NOSCHED context is closed.
This change removes the WARN_ON.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Reading from the signal{1,2} files requires a spu_acquire_saved, so
make these files write-only for contexts created with
SPU_CREATE_NOSCHED.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
The current SPU context saving procedure in SPUFS unexpectedly
restarts MFC when halting decrementer, because MFC_CNTL[Dh] is set
without MFC_CNTL[Sm]. This bug causes, for example, saving broken DMA
queues. Here is a patch to fix the problem.
Signed-off-by: Kazunori Asayama <asayama@sm.sony.co.jp>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>