Add ability to override power management bits of 310 controllers
(dynamic clock gating and standby mode) through OF entries. As the
saved register is only applied when working on a supported controller,
it is safe to save the settings.
In order to maintain existing behavior, if the settings are not found
in the DT, the corresponding feature will be enabled.
Signed-off-by: Brad Mouring <brad.mouring@ni.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
According to commit 2503a5ecd8
"ARM: 6201/1: RealView: Do not use outer_sync() on ARM11MPCore
boards with L220" Some PB11MPCore RealView core tiles have broken
outer_sync.
We got rid of the custom barriers from the machine by disabling
outer sync, but that was just for the boardfile case. We have
to be able to do the same in the device tree case.
Since __l2c_init() is cloning and copying the L2C vtable,
we pass an argument to this function to optionally numb
the outer sync operation if desired, before initializing
the cache.
After this we can set up the cache correctly on the RealView
PB11MPCore. This was tested on a PB11MPCore known to have the
issue. Before this, spurious crashes would occur if we try to
set up the cache properly, after this it boots rock solid.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: devicetree@vger.kernel.org
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The RealView ARM11MPCore enables parity, eventmon and shared
override in the cache controller through its current boardfile,
but the code and DT bindings for the ARM L220 is currently
lacking the ability to set this up from DT. Add the required
bool parameters for parity and shared override, but keep
eventmon out of it: this should be enabled by the event
monitor code.
Cc: devicetree@vger.kernel.org
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
"CoreLink Level 2 Cache Controller L2C-310", p. 2-15, section 2.3.2
Shareable attribute" states:
"The default behavior of the cache controller with respect to the
shareable attribute is to transform Normal Memory Non-cacheable
transactions into:
- cacheable no allocate for reads
- write through no write allocate for writes."
Depending on the system architecture, this may cause memory corruption
in the presence of bus mastering devices (e.g. OHCI). To avoid such
corruption, the default behavior can be disabled by setting the Shared
Override bit in the Auxiliary Control register.
Currently the Shared Override bit can be set only using C code:
- by calling l2x0_init() directly, which is deprecated,
- by setting/clearing the bit in the machine_desc.l2c_aux_val/mask
fields, but using values differing from 0/~0 is also deprecated.
Hence add support for an "arm,shared-override" device tree property for
the l2c device node. By specifying this property, affected systems can
indicate that non-cacheable transactions must not be transformed.
Then, it's up to the OS to decide. The current behavior is to set the
"shared attribute override enable" bit, as there may exist kernel linear
mappings and cacheable aliases for the DMA buffers, even if CMA is
enabled.
See also commit 1a8e41cd67 ("ARM: 6395/1: VExpress: Set bit 22 in
the PL310 (cache controller) AuxCtlr register"):
"Clearing bit 22 in the PL310 Auxiliary Control register (shared
attribute override enable) has the side effect of transforming
Normal Shared Non-cacheable reads into Cacheable no-allocate reads.
Coherent DMA buffers in Linux always have a Cacheable alias via the
kernel linear mapping and the processor can speculatively load
cache lines into the PL310 controller. With bit 22 cleared,
Non-cacheable reads would unexpectedly hit such cache lines leading
to buffer corruption."
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
These options make it possible to overwrites the data and instruction
prefetching behavior of the arm pl310 cache controller.
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Avoid passing the auxiliary control register value through the enable
method. In the resume path, we have to read the value stored in
l2x0_saved_regs.aux_ctrl, only to have it immediately written back by
l2c_enable(). We can avoid this if we have __l2c_init() save the value
directly to l2x0_saved_regs.aux_ctrl before calling the specific enable
method.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Some L2C caches have a bit which allows non-secure software to control
the cache lockdown. Some platforms are unable to set this bit. To
avoid receiving an abort while trying to unlock the cache lines, check
the state of this bit before unlocking. We do this by providing a new
method in the l2c_init_data to perform the unlocking.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
l2c_configure() does not follow the pattern of other l2c_* functions.
Fix this so that it does to avoid future confusion.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Before calling the controller specific configuration function, write
the auxiliary control register first, so that bits shared with other
registers (such as the prefetch control register) are not overwritten
by the later write to the auxctrl register.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
l2c_enable() is documented that it must not be called if the cache has
already been enabled. Unfortunately, commit 6b49241ac2 ("ARM: 8259/1:
l2c: Refactor the driver to use commit-like interface") changed this
without updating the comment, for very little reason. Revert this
change and restore the expected behaviour.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Allow prefetch settings overriding by device tree, in case
l2x0_cache_size_of_parse() returns value, prefetch tuning
properties are silently ignored. E.g. arm,double-linefill* and
arm,prefetch*.
This happens for example, when "cache-size" or "cache-sets"
properties haven't been filled in l2c dt node.
Comments from Fabrice Gasnier:
Allow device tree to override the L2C prefetch settings, even when
l2x0_cache_size_of_parse() fails to parse the cache geometry due to (eg)
missing "cache-size" or "cache-sets" properties.
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Reviewed-by: Tomasz Figa <tomasz.figa@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Make sure that we can read the "cache-level" property from the L2 cache
controller node, and ensure its value is 2.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Pull ARM updates from Russell King:
- clang assembly fixes from Ard
- optimisations and cleanups for Aurora L2 cache support
- efficient L2 cache support for secure monitor API on Exynos SoCs
- debug menu cleanup from Daniel Thompson to allow better behaviour for
multiplatform kernels
- StrongARM SA11x0 conversion to irq domains, and pxa_timer
- kprobes updates for older ARM CPUs
- move probes support out of arch/arm/kernel to arch/arm/probes
- add inline asm support for the rbit (reverse bits) instruction
- provide an ARM mode secondary CPU entry point (for Qualcomm CPUs)
- remove the unused ARMv3 user access code
- add driver_override support to AMBA Primecell bus
* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (55 commits)
ARM: 8256/1: driver coamba: add device binding path 'driver_override'
ARM: 8301/1: qcom: Use secondary_startup_arm()
ARM: 8302/1: Add a secondary_startup that assumes ARM mode
ARM: 8300/1: teach __asmeq that r11 == fp and r12 == ip
ARM: kprobes: Fix compilation error caused by superfluous '*'
ARM: 8297/1: cache-l2x0: optimize aurora range operations
ARM: 8296/1: cache-l2x0: clean up aurora cache handling
ARM: 8284/1: sa1100: clear RCSR_SMR on resume
ARM: 8283/1: sa1100: collie: clear PWER register on machine init
ARM: 8282/1: sa1100: use handle_domain_irq
ARM: 8281/1: sa1100: move GPIO-related IRQ code to gpio driver
ARM: 8280/1: sa1100: switch to irq_domain_add_simple()
ARM: 8279/1: sa1100: merge both GPIO irqdomains
ARM: 8278/1: sa1100: split irq handling for low GPIOs
ARM: 8291/1: replace magic number with PAGE_SHIFT macro in fixup_pv code
ARM: 8290/1: decompressor: fix a wrong comment
ARM: 8286/1: mm: Fix dma_contiguous_reserve comment
ARM: 8248/1: pm: remove outdated comment
ARM: 8274/1: Fix DEBUG_LL for multi-platform kernels (without PL01X)
ARM: 8273/1: Seperate DEBUG_UART_PHYS from DEBUG_LL on EP93XX
...
The aurora_inv_range(), aurora_clean_range() and aurora_flush_range()
functions are highly redundant, both in source and in object code, and
they are harder to understand than necessary.
By moving the range loop into the aurora_pa_range() function, they
become trivial wrappers, and the object code start looking like what
one would expect for an optimal implementation.
Further optimization may be possible by using the per-CPU "virtual"
registers to avoid the spinlocks in most cases.
(on Armada 370 RD and Armada XP GP, boot tested, plus a little bit of
DMA traffic by reading data from a SD card)
Reviewed-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The aurora cache controller is the only remaining user of a couple
of functions in this file and are completely unused when that is
disabled, leading to build warnings:
arch/arm/mm/cache-l2x0.c:167:13: warning: 'l2x0_cache_sync' defined but not used [-Wunused-function]
arch/arm/mm/cache-l2x0.c:184:13: warning: 'l2x0_flush_all' defined but not used [-Wunused-function]
arch/arm/mm/cache-l2x0.c:194:13: warning: 'l2x0_disable' defined but not used [-Wunused-function]
With the knowledge that the code is now aurora-specific, we can
simplify it noticeably:
- The pl310 errata workarounds are not needed on aurora and can be removed
- As confirmed by Thomas Petazzoni from the data sheet, the cache_wait()
macro is never needed.
- No need to hold the lock across atomic cache sync
- We can load the l2x0_base into a local variable across operations
There should be no functional change in this patch, but readability
and the generated object code improves, along with avoiding the
warnings.
(on Armada 370 RD and Armada XP GP, boot tested, plus a little bit of
DMA traffic by reading data from a SD card)
Acked-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
It is not clear from the filename, and comment at the begining adds to the
confusion by not listing L310. Fix it.
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Firmware on certain boards (e.g. ODROID-U3) can leave incorrect L2C prefetch
settings configured in registers leading to crashes if L2C is enabled
without overriding them. This patch introduces bindings to enable
prefetch settings to be specified from DT and necessary support in the
driver.
[mszyprow: rebased onto v3.18-rc1, added error message when prefetch related
dt property has been provided without any value]
Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Nishanth Menon <nm@ti.com>
Acked-by: Nishanth Menon <nm@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Because certain secure hypervisor do not allow writes to individual L2C
registers, but rather expect set of parameters to be passed as argument
to secure monitor calls, there is a need to provide an interface for the
L2C driver to ask the firmware to configure the hardware according to
specified parameters. This patch adds such.
Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Nishanth Menon <nm@ti.com>
Acked-by: Nishanth Menon <nm@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Certain implementations of secure hypervisors (namely the one found on
Samsung Exynos-based boards) do not provide access to individual L2C
registers. This makes the .write_sec()-based interface insufficient and
provoking ugly hacks.
This patch is first step to make the driver not rely on availability of
writes to individual registers. This is achieved by refactoring the
driver to use a commit-like operation scheme: all register values are
prepared first and stored in an instance of l2x0_regs struct and then a
single callback is responsible to flush those values to the hardware.
[mszyprow: rebased onto 'ARM: l2c: use l2c_write_sec() for restoring
latency and filter regs' patch]
Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Nishanth Menon <nm@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
All four register for latency and filter settings cannot be written in
non-secure mode and they should go through l2c_write_sec(). More on this
can be found in CoreLink Level 2 Cache Controller L2C-310 Technical
Reference Manual, 3.2. Register summary, table 3.1. This have been checked
the TRM for r3p3, but it should be uniform for all revisions.
Reported-by: Nishanth Menon <nm@ti.com>
Suggested-by: Tomasz Figa <tomasz.figa@gmail.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Nishanth Menon <nm@ti.com>
Acked-by: Nishanth Menon <nm@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Russell King suggested [1]:
"I'd ask for one change. Please make all these messages start with
"L2C-310 OF" not "PL310 OF:". The device is described in ARM
documentation as a L2C-310 not PL310. (Also note the : is dropped
too - most of the other messages don't have the : either.)
The:
"PL310 OF: cache setting yield illegal associativity
PL310 OF: -1073346556 calculated, only 8 and 16 legal"
message could also be changed to something like:
"L2C-310 OF cache associativity %d invalid, only 8 or 16 permittedn"
[1] http://www.spinics.net/lists/arm-kernel/msg372776.html
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Since commit f3354ab674 ("ARM: 8169/1: l2c: parse cache properties from
ePAPR definitions") the following error is seen on imx6q:
[ 0.000000] PL310 OF: cache setting yield illegal associativity
[ 0.000000] PL310 OF: -2147097556 calculated, only 8 and 16 legal
As imx6q does not pass the "cache-size" and "cache-sets" properties in DT, the function l2x0_cache_size_of_parse() returns early and keep the 'associativity' pointer uninitialized.
To fix this problem, return error codes inside l2x0_cache_size_of_parse() and only use the 'associativity' pointer result if l2x0_cache_size_of_parse() succeeds.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
When both 'cache-size' and 'cache-sets' are specified for a L2 cache
controller node, parse those properties and set up the
set size based on which type of L2 cache controller we are using.
Update the L2 cache controller Device Tree binding with the optional
'cache-size', 'cache-sets', 'cache-block-size' and 'cache-line-size'
properties. These come from the ePAPR specification.
Using the cache size, number of sets and cache line size we can
calculate desired associativity of the L2 cache. This is done
by the calculation:
set size = cache size / sets
ways = set size / line size
way size = cache size / ways = sets * line size
associativity = cache size / way size
Example output from the PB1176 DT that look like this:
L2: l2-cache {
compatible = "arm,l220-cache";
(...)
arm,override-auxreg;
cache-size = <131072>; // 128kB
cache-sets = <512>;
cache-line-size = <32>;
};
Ends up like this:
L2C OF: override cache size: 131072 bytes (128KB)
L2C OF: override line size: 32 bytes
L2C OF: override way size: 16384 bytes (16KB)
L2C OF: override associativity: 8
L2C: DT/platform modifies aux control register: 0x02020fff -> 0x02030fff
L2C-220 cache controller enabled, 8 ways, 128 kB
L2C-220: CACHE_ID 0x41000486, AUX_CTRL 0x06030fff
Which is consistent with the value earlier hardcoded for the
PB1176 platform.
This patch is an extended version based on the initial patch
by Florian Fainelli.
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Ensure that platform maintainers check the CPU part number in the right
manner: the CPU part number is meaningless without also checking the
CPU implement(e|o)r (choose your preferred spelling!) Provide an
interface which returns both the implementer and part number together,
and update the definitions to include the implementer.
Mark the old function as being deprecated... indeed, using the old
function with the definitions will now always evaluate as false, so
people must update their un-merged code to the new function. While
this could be avoided by adding new definitions, we'd also have to
create new names for them which would be awkward.
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The revision checking in l2c310_enable() was not correct; we were
masking the part number rather than the revision number. Fix this
to use the correct macro.
Fixes: 4374d64933 ("ARM: l2c: add automatic enable of early BRESP")
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
When a PL310 cache is used on a system that provides hardware
coherency, the outer cache sync operation is useless, and can be
skipped. Moreover, on some systems, it is harmful as it causes
deadlocks between the Marvell coherency mechanism, the Marvell PCIe
controller and the Cortex-A9.
To avoid this, this commit introduces a new Device Tree property
'arm,io-coherent' for the L2 cache controller node, valid only for the
PL310 cache. It identifies the usage of the PL310 cache in an I/O
coherent configuration. Internally, it makes the driver disable the
outer cache sync operation.
Note that technically speaking, a fully coherent system wouldn't
require any of the other .outer_cache operations. However, in
practice, when booting secondary CPUs, these are not yet coherent, and
therefore a set of cache maintenance operations are necessary at this
point. This explains why we keep the other .outer_cache operations and
only ->sync is disabled.
While in theory any write to a PL310 register could cause the
deadlock, in practice, disabling ->sync is sufficient to workaround
the deadlock, since the other cache maintenance operations are only
used in very specific situations.
Contrary to previous versions of this patch, this new version does not
simply NULL-ify the ->sync member, because the l2c_init_data
structures are now 'const' and therefore cannot be modified, which is
a good thing. Therefore, this patch introduces a separate
l2c_init_data instance, called of_l2c310_coherent_data.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
As we have now removed all instances of the L2C-310 having its cache
size "modified" via platform/SoC code, discourage new cases showing
up by printing a warning.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We no longer need or require the .set_debug method; we handle everything
it used to do via the .write_sec method instead.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Since we always write to these during the cache initialisation, it is
a good idea to always have the non-secure access bit set. Set it in
core code.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The AXI bus protocol requires that a write response should only be
sent back to the master when the last write has been accepted. Early
BRESP allows the L2C-310 to send the write response as soon as the
store buffer accepts the write address.
Cortex-A9 processors can signal to the L2C-310 that they wish to be
notified early, and if this optimisation is enabled, the L2C-310 can
signal an early write response.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Move the L2 cache register saving to a more sensible location - after
the cache has been enabled, and fixups have been run. We move the
saving of the auxiliary control register into the ->save function as
well which makes everything operate in a sane and maintainable way.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We have a mixture of different devices with different register layouts,
but we group all the bits together in an opaque mess. Split them out
into those which are L2C-310 specific and ones which refer to earlier
devices. Provide full auxiliary control register definitions.
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Rather than having SoCs work around L2C erratum themselves, move them
into core code. This erratum affects the double linefill feature which
needs to be disabled for r3p0 to r3p1-50rel0.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
When Linux is running in the non-secure world, any write to a secure
L2C register will generate an abort. Platforms normally have to call
firmware to work around this. Provide a hook for them to intercept
any L2C secure register write.
l2c_write_sec() avoids writes to secure registers which are already set
to the appropriate value, thus avoiding the overhead of needlessly
calling into the secure monitor.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Move the way size calculation data (base of way size) out of the
switch statement into the provided initialisation data.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Rather than assuming these are always 8-way, it can be decoded from the
auxillary register in the same manner as L2C-210.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Rather than decoding this from the ID register, store it in the
l2c_init_data structure. This simplifies things some more, and
allows us to better provide further details as to how we're
driving the cache. We print the cache ID value anyway should we
need to precisely identify the cache hardware.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
non-OF initialisation has never been used with any cache controller
which isn't an ARM cache controller, so we can safely get rid of the
old (and buggy) l2x0_*-based operations structure.
This is also the last reference to:
- l2x0_clean_line()
- l2x0_inv_line()
- l2x0_flush_line()
- l2x0_flush_all()
- l2x0_clean_all()
- l2x0_inv_all()
- l2x0_inv_range()
- l2x0_clean_range()
- l2x0_flush_range()
- l2x0_enable()
- l2x0_resume()
so kill those functions too.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The Broadcom L2C-310 devices use ARMs L2C-310 R2P3 or later. These
require no errata workarounds, and so we can directly call the l2c210
functions from their methods.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The L2C-220 is different from the L2C-210 and L2C-310 in that every
operation is a background operation: this means we have to use
spinlocks to protect all operations, and we have to wait for every
operation to complete.
Should a second operation be attempted while a previous operation
is in progress, the response will be an imprecise abort.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Where no errata affect the L2C-310 handlers, they are functionally
equivalent to L2C-210. Re-use the L2C-210 handlers for the L2C-310
part.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Implement L2C-310 erratum 588369 by overriding the invalidate range
and flush range methods in the outer_cache operations structure.
This allows us to sensibly contain the erratum code in one place
without affecting other locations/implemetations.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Implement L2C-310 erratum 727915 by overriding the flush_all method
in the outer_cache operations structure. This allows us to sensibly
contain the erratum code in one place without affecting other
locations or implementations.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
