Devices that use CAPP DMA mode (such as the Mellanox CX4) require bus
master to be enabled in order for the CAPI traffic to flow. This should
be harmless to enable for other cxl devices, so unconditionally enable
it in the adapter init flow.
Signed-off-by: NIan Munsie <imunsie@au1.ibm.com>
Reviewed-by: NAndrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: NFrederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This extends the check that the adapter is in a CAPI capable slot so
that it may be called by external users in the kernel API. This will be
used by the upcoming Mellanox CX4 support, which needs to know ahead of
time if the card can be switched to cxl mode so that it can leave it in
PCI mode if it is not.

This API takes a parameter to check if CAPP DMA mode is supported, which
it currently only allows on P8NVL systems, since that mode currently has
issues accessing memory < 4GB on P8, and we cannot realistically avoid
that.

This API does not currently check if a CAPP unit is available (i.e. not
already assigned to another PHB) on P8. Doing so would be racy since it
is assigned on a first come first serve basis, and so long as CAPP DMA
mode is not supported on P8 we don't need this, since the only
anticipated user of this API requires CAPP DMA mode.

Cc: Philippe Bergheaud <felix@linux.vnet.ibm.com>
Signed-off-by: NIan Munsie <imunsie@au1.ibm.com>
Reviewed-by: NAndrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: NFrederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Use for_each_compatible_node() macro instead of open coding it.

Generated by Coccinelle.
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Reviewed-by: NAndrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: NIan Munsie <imunsie@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

One should not attempt to switch a PHB into CAPI mode if there is
a switch between the PHB and the adapter. This patch modifies the
cxl driver to ignore CAPI adapters misplaced in switched slots.
Signed-off-by: NPhilippe Bergheaud <felix@linux.vnet.ibm.com>
Reviewed-by: NFrederic Barrat <fbarrat@linux.vnet.ibm.com>
Acked-by: NIan Munsie <imunsie@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The Kconfig/Makefile currently controlling compilation of this code is:

drivers/misc/cxl/Kconfig:config CXL_BASE
drivers/misc/cxl/Kconfig:       bool

drivers/misc/cxl/Makefile:obj-$(CONFIG_CXL_BASE)          += base.o

...meaning that it currently is not being built as a module by anyone.

Lets convert the one module_init into device_initcall so that
when reading the driver it more clear that it is builtin-only.

Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.

We don't replace module.h with init.h since the file is doing
other modular stuff (module_get/put) even though it is built-in.

Cc: Ian Munsie <imunsie@au1.ibm.com>
Cc: Michael Neuling <mikey@neuling.org>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: NIan Munsie <imunsie@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The PSL Slice Error Register (PSL_SERR_An) reports implementation
dependent AFU errors, in the form of a bitmap. The PSL_SERR_An
register content is printed in the form of hex dump debug message.

This patch decodes the PSL_ERR_An register contents, and prints a
specific error message for each possible error bit. It also dumps
the secondary registers AFU_ERR_An and PSL_DSISR_An, that may
contain extra debug information.

This patch also removes the large WARN message that used to report
the cxl slice error interrupt, and replaces it by a short informative
message, that draws attention to AFU implementation errors.
Signed-off-by: NPhilippe Bergheaud <felix@linux.vnet.ibm.com>
Acked-by: NIan Munsie <imunsie@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

If a kernel context is initialised and does not have any AFU interrupts
allocated it will cause a NULL pointer dereference when the context is
detached since the irq_names list will not have been initialised.

Move the initialisation of the irq_names list into the cxl_context_init
routine so that it will be valid for the entire lifetime of the context
and will not cause a NULL pointer dereference.
Signed-off-by: NIan Munsie <imunsie@au1.ibm.com>
Reviewed-by: NAndrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

An issue was noted in our debug logs where the XSL would leave the RA
bit asserted after an AFU reset operation, which would effectively
prevent further AFU reset operations from working.

Workaround the issue by clearing the RA bit with an MMIO write if it is
still asserted after any AFU control operation.
Signed-off-by: NIan Munsie <imunsie@au1.ibm.com>
Reviewed-by: NFrederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The AFU disable operation has a bug where it will not clear the enable
bit and therefore will have no effect. To date this has likely been
masked by fact that we perform an AFU reset before the disable, which
also has the effect of clearing the enable bit, making the following
disable operation effectively a noop on most hardware. This patch
modifies the afu_control function to take a parameter to clear from the
AFU control register so that the disable operation can clear the
appropriate bit.

This bug was uncovered on the Mellanox CX4, which uses an XSL rather
than a PSL. On the XSL the reset operation will not complete while the
AFU is enabled, meaning the enable bit was still set at the start of the
disable and as a result this bug was hit and the disable also timed out.

Because of this difference in behaviour between the PSL and XSL, this
patch now makes the reset dependent on the card using a PSL to avoid
waiting for a timeout on the XSL. It is entirely possible that we may be
able to drop the reset altogether if it turns out we only ever needed it
due to this bug - however I am not willing to drop it without further
regression testing and have added comments to the code explaining the
background.

This also fixes a small issue where the AFU_Cntl register was read
outside of the lock that protects it.
Signed-off-by: NIan Munsie <imunsie@au1.ibm.com>
Reviewed-by: NFrederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The Scheduled Process Area is allocated dynamically with enough pages to
fit at least as many processes as the AFU descriptor indicated. Since
the calculation is non-trivial, it does this by calculating how many
processes could fit in an allocation of a given order, and increasing
that order until it can fit enough processes or hits the maximum
supported size.

Currently, it will start this search using a SPA of 2 pages instead of
1. This can waste a page of memory if the AFU's maximum number of
supported processes was small enough to fit in one page.

Fix the algorithm to start the search at 1 page.
Signed-off-by: NIan Munsie <imunsie@au1.ibm.com>
Reviewed-by: NFrederic Barrat <fbarrat@linux.vnet.ibm.com>
Reviewed-by: NAndrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

If the AFU descriptor of an AFU directed AFU indicates that it supports
0 maximum processes, we will accept that value and attempt to use it.
The SPA will still be allocated (with 2 pages due to another minor bug
and room for 958 processes), and when a context is allocated we will
pass the value of 0 to idr_alloc as the maximum. However, idr_alloc will
treat that as meaning no maximum and will allocate a context number and
we return a valid context.

Conceivably, this could lead to a buffer overflow of the SPA if more
than 958 contexts were allocated, however this is mitigated by the fact
that there are no known AFUs in the wild with a bogus AFU descriptor
like this, and that only the root user is allowed to flash an AFU image
to a card.

Add a check when validating the AFU descriptor to reject any with 0
maximum processes.

We do still allow a dedicated process only AFU to indicate that it
supports 0 contexts even though that is forbidden in the architecture,
as in that case we ignore the value and use 1 instead. This is just on
the off-chance that such a dedicated process AFU may exist (not that I
am aware of any), since their developers are less likely to have cared
about this value at all.
Signed-off-by: NIan Munsie <imunsie@au1.ibm.com>
Reviewed-by: NFrederic Barrat <fbarrat@linux.vnet.ibm.com>
Reviewed-by: NAndrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This provides AFU drivers a means to associate private data with a cxl
context. This is particularly intended for make the new callbacks for
driver specific events easier for AFU drivers to use, as they can easily
get back to any private data structures they may use.
Signed-off-by: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NIan Munsie <imunsie@au1.ibm.com>
Signed-off-by: Philippe Bergheaud <felix@linux.vnet.ibm.com
Reviewed-by: NMatthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: NAndrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This adds an afu_driver_ops structure with fetch_event() and
event_delivered() callbacks. An AFU driver such as cxlflash can fill
this out and associate it with a context to enable passing custom AFU
specific events to userspace.

This also adds a new kernel API function cxl_context_pending_events(),
that the AFU driver can use to notify the cxl driver that new specific
events are ready to be delivered, and wake up anyone waiting on the
context wait queue.

The current count of AFU driver specific events is stored in the field
afu_driver_events of the context structure.

The cxl driver checks the afu_driver_events count during poll, select,
read, etc. calls to check if an AFU driver specific event is pending,
and calls fetch_event() to obtain and deliver that event. This way, the
cxl driver takes care of all the usual locking semantics around these
calls and handles all the generic cxl events, so that the AFU driver
only needs to worry about it's own events.

fetch_event() return a struct cxl_event_afu_driver_reserved, allocated
by the AFU driver, and filled in with the specific event information and
size. Total event size (header + data) should not be greater than
CXL_READ_MIN_SIZE (4K).

Th cxl driver prepends an appropriate cxl event header, copies the event
to userspace, and finally calls event_delivered() to return the status of
the operation to the AFU driver. The event is identified by the context
and cxl_event_afu_driver_reserved pointers.

Since AFU drivers provide their own means for userspace to obtain the
AFU file descriptor (i.e. cxlflash uses an ioctl on their scsi file
descriptor to obtain the AFU file descriptor) and the generic cxl driver
will never use this event, the ABI of the event is up to each individual
AFU driver.
Signed-off-by: NPhilippe Bergheaud <felix@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

On bare-metal, when a device is attached to the cxl card, lsvpd shows
a location code such as (with cxlflash):
     # lsvpd -l sg22
     ...
     *YL U78CB.001.WZS0073-P1-C33-B0-T0-L0
which makes it hard to easily identify the cxl adapter owning the
flash device, since in this example C33 refers to a P8 processor.

lsvpd looks in the parent devices until it finds a location code, so the
device node for the vPHB ends up being used.

By reusing the device node of the adapter for the vPHB, lsvpd shows:
     # lsvpd -l sg16
     ...
     *YL U78C9.001.WZS09XA-P1-C7-B1-T0-L3
where C7 is the PCI slot of the cxl adapter.

On powerVM, the vPHB was already using the adapter device node, so
there's no change there.

Tested by cxlflash on bare-metal and powerVM.
Signed-off-by: NFrederic Barrat <fbarrat@linux.vnet.ibm.com>
Reviewed-by: NMatthew R. Ochs <mrochs@linux.vnet.ibm.com>
Acked-by: NIan Munsie <imunsie@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This adds support for using CAPP DMA mode, which is required for XSL
based cards such as the Mellanox CX4 to function.

This is currently an RFC as it depends on the corresponding support to
be merged into skiboot first, which was submitted here:
http://patchwork.ozlabs.org/patch/625582/

In the event that the skiboot on the system does not have the above
support, it will indicate as such in the kernel log and abort the init
process.
Signed-off-by: NIan Munsie <imunsie@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The XSL (Translation Service Layer) is a stripped down version of the
PSL (Power Service Layer) used in some cards such as the Mellanox CX4.

Like the PSL, it implements the CAIA architecture, but has a number of
differences, mostly in it's implementation dependent registers. This
adds an ops structure to abstract these differences to bring initial
support for XSL CAPI devices.

The XSL does not implement the optional architected SERR register,
however while it treats it as a reserved register and should work with
no special treatment, attempting to access it will cause the XSL_FEC
(First Error Capture) register to be filled out, preventing it from
capturing any subsequent errors. Therefore, this patch also prevents the
kernel from trying to set up the SERR register so that the FEC register
may still be useful, and to save one interrupt.

The XSL also uses a special DMA cxl mode, which uses a slightly
different init sequence for the CAPP and PHB. The kernel support for
this will be in a future patch once the corresponding support has been
merged into skiboot.
Co-authored-by: NIan Munsie <imunsie@au1.ibm.com>
Signed-off-by: NIan Munsie <imunsie@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

In the kernel API, it is possible to attempt to allocate AFU interrupts
after already starting a context. Since the process element structure
used by the hardware is only filled out at the time the context is
started, it will not be updated with the interrupt numbers that have
just been allocated and therefore AFU interrupts will not work unless
they were allocated prior to starting the context.

This can present some difficulties as each CAPI enabled PCI device in
the kernel API has a default context, which may need to be started very
early to enable translations, potentially before interrupts can easily
be set up.

This patch makes the API more flexible to allow interrupts to be
allocated after a context has already been started and takes care of
updating the PE structure used by the hardware and notifying it to
discard any cached copy it may have.

The update is currently performed via a terminate/remove/add sequence.
This is necessary on some hardware such as the XSL that does not
properly support the update LLCMD.

Note that this is only supported on powernv at present - attempting to
perform this ordering on PowerVM will raise a warning.
Signed-off-by: NIan Munsie <imunsie@au1.ibm.com>
Reviewed-by: NFrederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Make a couple more variables static. Found by sparse.
Signed-off-by: NAndrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: fbarrat@linux.vnet.ibm.com
Reviewed-by: NMatthew R. Ochs <mrochs@linux.vnet.ibm.com>
Acked-by: NIan Munsie <imunsie@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

In the PowerVM environment, the PHYP CoherentAccel component manages
the state of the Coherent Accelerator Processor Interface adapter and
virtualizes CAPI resources, handles CAPP, PSL, PSL Slice errors - and
interrupts - and provides a new set of hcalls for the OS APIs to utilize
Accelerator Function Unit (AFU).

During the course of operation, a coherent platform function can
encounter errors. Some possible reason for errors are:
• Hardware recoverable and unrecoverable errors
• Transient and over-threshold correctable errors

PHYP implements its own state model for the coherent platform function.
The state of the AFU is available through a hcall.

The current implementation of the cxl driver, for the PowerVM
environment, checks this state of the AFU only when an action is
requested - open a device, ioctl command, memory map, attach/detach a
process - from an external driver - cxlflash, libcxl. If an error is
detected the cxl driver handles the error according the content of the
Power Architecture Platform Requirements document.

But in case of low-level troubles (or error injection), the PHYP
component may reset the card and change the AFU state. The PHYP
interface doesn't provide any way to be notified when that happens thus
implies that the cxl driver:
• cannot handle immediatly the state change of the AFU.
• cannot notify other drivers (cxlflash, ...)

The purpose of this patch is to wake up the cpu periodically to check
the current state of each AFU and to see if we need to enter an error
recovery path.
Signed-off-by: NChristophe Lombard <clombard@linux.vnet.ibm.com>
Acked-by: NIan Munsie <imunsie@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

cxl devices typically access memory using an MMU in much the same way as
the CPU, and each context includes a state register much like the MSR in
the CPU. Like the CPU, the state register includes a bit to enable
relocation, which we currently always enable.

In some cases, it may be desirable to allow a device to access memory
using real addresses instead of effective addresses, so this adds a new
API, cxl_set_translation_mode, that can be used to disable relocation
on a given kernel context. This can allow for the creation of a special
privileged context that the device can use if it needs relocation
disabled, and can use regular contexts at times when it needs relocation
enabled.

This interface is only available to users of the kernel API for obvious
reasons, and will never be supported in a virtualised environment.

This will be used by the upcoming cxl support in the mlx5 driver.
Signed-off-by: NIan Munsie <imunsie@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

In the cxl kernel API, it is possible to create a context and start it
without allocating any interrupts. Since we assign or allocate the PSL
interrupt when allocating AFU interrupts this will lead to a situation
where we start the context with no means to take any faults.

The user API is not affected as it always goes through the cxl interrupt
allocation code paths and will have the PSL interrupt allocated or
assigned, even if no AFU interrupts were requested.

This checks that at least one interrupt is configured at the time of
attach, and if not it will assign the multiplexed PSL interrupt for
powernv, or allocate a single interrupt for PowerVM.
Signed-off-by: NIan Munsie <imunsie@au1.ibm.com>
Reviewed-by: NFrederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

These defines are not used, but other equivalent definitions
(CXL_SPA_SW_CMD_*) are used. Remove the unused defines.
Signed-off-by: NIan Munsie <imunsie@au1.ibm.com>
Reviewed-by: NAndrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

num_of_process is a 16 bit field, theoretically allowing an AFU to
support 16K processes, however the scheduled process area currently has
a maximum size of 1MB, which limits the maximum number of processes to
7704.

Some AFUs may not necessarily care what the limit is and just want to be
able to use the maximum by setting the field to 16K. To allow these to
work, detect this situation and use the maximum size for the SPA.

Downgrade the WARN_ON to a dev_warn.
Signed-off-by: NIan Munsie <imunsie@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Use no-op messages in place of cross-partition interrupts when nacking a
put message in the GRU.  This allows us to remove MMR's as a destination
from the GRU driver.
Tested-by: NJohn Estabrook <estabrook@sgi.com>
Tested-by: NGary Kroening <gfk@sgi.com>
Tested-by: NNathan Zimmer <nzimmer@sgi.com>
Signed-off-by: NDimitri Sivanich <sivanich@sgi.com>
Signed-off-by: NMike Travis <travis@sgi.com>
Cc: Andrew Banman <abanman@sgi.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <rja@sgi.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160429215406.012228480@asylum.americas.sgi.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Ensure that mei_cl_read_start is called under the device lock
also in the bus layer. The function updates global ctrl_wr_list
which should be locked.

Cc: <stable@vger.kernel.org> #4.4+
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

complete_all() should only be called once, doing it twice is a clear bug.

8565adbc ("drivers/misc/ti-st: fix read fw version cmd") added the
additional complete_all() call. Since we call complete_all() when
leaving the function we can drop the complete_all() call inside
true branch of the if statement.
Signed-off-by: NDaniel Wagner <daniel.wagner@bmw-carit.de>
Cc: Pavan Savoy <pavan_savoy@ti.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

It's harmless but, if "enable" isn't set, then we pass uninitialized
values to qcom_coincell_chgr_config().  The values aren't used, but
let's silence the warning anyway.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Acked-by: NTim Bird <tim.bird@sonymobile.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The 93xx46 driver is using spi_dev_get() apparently just to take a copy
of the SPI device used to instantiate it but never calls spi_dev_put()
to free it.  Since the device is guaranteed to exist between probe() and
remove() there should be no need for the driver to take an extra
reference to it so fix the leak by just using a straight assignment.
Signed-off-by: NMark Brown <broonie@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The at25 driver is using spi_dev_get() apparently just to take a copy
of the SPI device used to instantiate it but never calls spi_dev_put()
to free it.  Since the device is guaranteed to exist between probe() and
remove() there should be no need for the driver to take an extra
reference to it so fix the leak by just using a straight assignment.
Signed-off-by: NMark Brown <broonie@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch moves to nvmem support in the driver to use callback
instead of regmap.
Signed-off-by: NSrinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch moves to nvmem support in the driver to use callback instead
of regmap.
Signed-off-by: NSrinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch moves to nvmem support in the driver to use callback instead
of regmap.
Signed-off-by: NSrinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

_PAGE_PRIVILEGED means the page can be accessed only by the kernel. This
is done to keep pte bits similar to PowerISA 3.0 Radix PTE format. User
pages are now marked by clearing _PAGE_PRIVILEGED bit.

Previously we allowed the kernel to have a privileged page in the lower
address range (USER_REGION). With this patch such access is denied.

We also prevent a kernel access to a non-privileged page in higher
address range (ie, REGION_ID != 0).

Both the above access scenarios should never happen.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jeremy Kerr <jk@ozlabs.org>
Cc: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Acked-by: NIan Munsie <imunsie@au1.ibm.com>
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This splits the _PAGE_RW bit into _PAGE_READ and _PAGE_WRITE. It also
removes the dependency on _PAGE_USER for implying read only. Few things
to note here is that, we have read implied with write and execute
permission. Hence we should always find _PAGE_READ set on hash pte
fault.

We still can't switch PROT_NONE to !(_PAGE_RWX). Auto numa depends on
marking a prot none pte _PAGE_WRITE. (For more details look at
b191f9b1 "mm: numa: preserve PTE write permissions across a NUMA
hinting fault")

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jeremy Kerr <jk@ozlabs.org>
Cc: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Acked-by: NIan Munsie <imunsie@au1.ibm.com>
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Both devm_ioremap() and devm_ioremap_wc() functions return either
a pointer to valid iomem region or NULL, check for IS_ERR() is improper
and may result in oops on error path. Now on error -ENOMEM is returned.

Fixes: 0ab163ad ("misc: sram: switch to ioremap_wc from ioremap")
Signed-off-by: NVladimir Zapolskiy <vz@mleia.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

A control message reply may not be received if either a link reset has
occurred or disconnection is initiated by the FW.
In the both cases the client state will be set straight to DISCONNECTED
and the driver will wait till timeout.
Adding DISCONNECTED state in the waiting condition will release the
client from the stall.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Timeout on notify request is not a fatal condition, and actually
cleaning control queues will disrupt other control flows of the
same client.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

When a message is received and amthif client is not in reading state
the message is ignored and left dangling in the queue. This may happen
after one of the amthif host connections is closed w/o completing the
reading. Another client will pick up a wrong message on next read
attempt which will lead to link reset.
To prevent this the driver has to properly discard the message when
amthif client is not in reading state.

Cc: <stable@vger.kernel.org> #4.2+
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

In the case when disconnection is initiated from the FW
the driver is flushing items from the write control list while
iterating over it:

mei_irq_write_handler()
    list_for_each_entry_safe(ctrl_wr_list)         <-- outer loop
         mei_cl_irq_disconnect_rsp()
             mei_cl_set_disconnected()
                 mei_io_list_flush(ctrl_wr_list)   <-- destorying list

We move the list flushing to the completion routine.

Cc: <stable@vger.kernel.org> #4.2+
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Global me_client_index is used only during the enumeration process and
can be effectively replaced by me_addr data from the last enumeration
response as we always enumerate clients in the increasing order.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>