The "PSERIES" in STD_EXCEPTION_PSERIES is to differentiate the macros
from the legacy iSeries versions, which are called
STD_EXCEPTION_ISERIES. It is not anything to do with pseries vs
powernv or powermac etc.

We removed the legacy iSeries code in 2012, in commit 8ee3e0d6x
("powerpc: Remove the main legacy iSerie platform code").

So remove "PSERIES" from the macros.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

EXCEPTION_RELON_PROLOG_PSERIES() only has two users,
STD_RELON_EXCEPTION_PSERIES() and STD_RELON_EXCEPTION_HV() both of
which "call" SET_SCRATCH0(), so just move SET_SCRATCH0() into
EXCEPTION_RELON_PROLOG_PSERIES().
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

EXCEPTION_PROLOG_PSERIES() only has two users, STD_EXCEPTION_PSERIES()
and STD_EXCEPTION_HV() both of which "call" SET_SCRATCH0(), so just
move SET_SCRATCH0() into EXCEPTION_PROLOG_PSERIES().
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Pasemi arch code finds the root of the PCI-e bus by searching the
device-tree for a node called 'pxp'. But the root bus has a compatible
property of 'pasemi,rootbus' so search for that instead.
Signed-off-by: Darren Stevens <darren@stevens-zone.net>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This patch adds a test for testing the new assembly strlen() for PPC32
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Fix 64-bit build]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The generic implementation of strlen() reads strings byte per byte.

This patch implements strlen() in assembly based on a read of entire
words, in the same spirit as what some other arches and glibc do.

On a 8xx the time spent in strlen is reduced by 3/4 for long strings.

strlen() selftest on an 8xx provides the following values:

Before the patch (ie with the generic strlen() in lib/string.c):

  len 256 : time = 1.195055
  len 016 : time = 0.083745
  len 008 : time = 0.046828
  len 004 : time = 0.028390

After the patch:

  len 256 : time = 0.272185 ==> 78% improvment
  len 016 : time = 0.040632 ==> 51% improvment
  len 008 : time = 0.033060 ==> 29% improvment
  len 004 : time = 0.029149 ==> 2% degradation

On a 832x:

Before the patch:

  len 256 : time = 0.236125
  len 016 : time = 0.018136
  len 008 : time = 0.011000
  len 004 : time = 0.007229

After the patch:

  len 256 : time = 0.094950 ==> 60% improvment
  len 016 : time = 0.013357 ==> 26% improvment
  len 008 : time = 0.010586 ==> 4% improvment
  len 004 : time = 0.008784
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This patch adds a test for strlen()

string.c contains a copy of strlen() from lib/string.c

The test first tests the correctness of strlen() by comparing
the result with libc strlen(). It tests all cases of alignment.

It them tests the duration of an aligned strlen() on a 4 bytes string,
on a 16 bytes string and on a 256 bytes string.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Drop change log from copy of string.c]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This patch renames memcmp test to memcmp_64 and adds a memcmp_32 test
for testing the 32 bits version of memcmp()
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Fix 64-bit build by adding build_32bit test]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

rtas_log_buf is a buffer to hold RTAS event data that are communicated
to kernel by hypervisor. This buffer is then used to pass RTAS event
data to user through proc fs. This buffer is allocated from
vmalloc (non-linear mapping) area.

On Machine check interrupt, register r3 points to RTAS extended event
log passed by hypervisor that contains the MCE event. The pseries
machine check handler then logs this error into rtas_log_buf. The
rtas_log_buf is a vmalloc-ed (non-linear) buffer we end up taking up a
page fault (vector 0x300) while accessing it. Since machine check
interrupt handler runs in NMI context we can not afford to take any
page fault. Page faults are not honored in NMI context and causes
kernel panic. Apart from that, as Nick pointed out,
pSeries_log_error() also takes a spin_lock while logging error which
is not safe in NMI context. It may endup in deadlock if we get another
MCE before releasing the lock. Fix this by deferring the logging of
rtas error to irq work queue.

Current implementation uses two different buffers to hold rtas error
log depending on whether extended log is provided or not. This makes
bit difficult to identify which buffer has valid data that needs to
logged later in irq work. Simplify this using single buffer, one per
paca, and copy rtas log to it irrespective of whether extended log is
provided or not. Allocate this buffer below RMA region so that it can
be accessed in real mode mce handler.

Fixes: b96672dd ("powerpc: Machine check interrupt is a non-maskable interrupt")
Cc: stable@vger.kernel.org # v4.14+
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The global mce data buffer that used to copy rtas error log is of 2048
(RTAS_ERROR_LOG_MAX) bytes in size. Before the copy we read
extended_log_length from rtas error log header, then use max of
extended_log_length and RTAS_ERROR_LOG_MAX as a size of data to be copied.
Ideally the platform (phyp) will never send extended error log with
size > 2048. But if that happens, then we have a risk of buffer overrun
and corruption. Fix this by using min_t instead.

Fixes: d368514c ("powerpc: Fix corruption when grabbing FWNMI data")
Reported-by: Michal Suchanek <msuchanek@suse.com>
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

It's identical to xive_teardown_cpu() so just use the latter
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Those overly verbose statement in the setup of the pool VP
aren't particularly useful (esp. considering we don't actually
use the pool, we configure it bcs HW requires it only). So
remove them which improves the code readability.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The kernel page table caches are tied to init_mm, so there is no
more need for them after userspace is finished.

destroy_context() gets called when we drop the last reference for an
mm, which can be much later than the task exit due to other lazy mm
references to it. We can free the page table cache pages on task exit
because they only cache the userspace page tables and kernel threads
should not access user space addresses.

The mapping for kernel threads itself is maintained in init_mm and
page table cache for that is attached to init_mm.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
[mpe: Merge change log additions from Aneesh]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

When the mm is being torn down there will be a full PID flush so
there is no need to flush the TLB on page size changes.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Some of these long running tests can time out on heavily loaded
systems, give them longer to run.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

These tests are currently failing on (some) big endian systems. Until
we can fix that, skip them unless we're on ppc64le.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Some of our selftests have only been tested on ppc64le and crash or
behave weirdly on ppc64/ppc32. So add a helper for checking the UTS
machine.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This makes it easy to run checkpatch with settings that I like.

Usage is eg:

  $ ./arch/powerpc/tools/checkpatch.sh -g origin/master..

To check all commits since origin/master.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Russell Currey <ruscur@russell.cc>

We recently added a warning in arch_local_irq_restore() to check that
the soft masking state matches reality.

Unfortunately it trips in a few places, which are not entirely trivial
to fix. The key problem is if we're doing function_graph tracing of
restore_math(), the warning pops and then seems to recurse. It's not
entirely clear because the system continuously oopses on all CPUs,
with the output interleaved and unreadable.

It's also been observed on a G5 coming out of idle.

Until we can fix those cases disable the warning for now.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

We've encountered a performance issue when multiple processors stress
{get,put}_mmio_atsd_reg(). These functions contend for
mmio_atsd_usage, an unsigned long used as a bitmask.

The accesses to mmio_atsd_usage are done using test_and_set_bit_lock()
and clear_bit_unlock(). As implemented, both of these will require
a (successful) stwcx to that same cache line.

What we end up with is thread A, attempting to unlock, being slowed by
other threads repeatedly attempting to lock. A's stwcx instructions
fail and retry because the memory reservation is lost every time a
different thread beats it to the punch.

There may be a long-term way to fix this at a larger scale, but for
now resolve the immediate problem by gating our call to
test_and_set_bit_lock() with one to test_bit(), which is obviously
implemented without using a store.

Fixes: 1ab66d1f ("powerpc/powernv: Introduce address translation services for Nvlink2")
Signed-off-by: Reza Arbab <arbab@linux.ibm.com>
Acked-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

kernel/dma/Kconfig already defines NEED_DMA_MAP_STATE, just select it
from CONFIG_PPC using the same condition as an if guard.
Signed-off-by: Christoph Hellwig <hch@lst.de>
[mpe: Move it under PPC]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

An arbitrary error in ppc4xx_msi_probe() quite likely results in a
crash similar to the following, seen after dma_alloc_coherent()
returned an error.

  Unable to handle kernel paging request for data at address 0x00000000
  Faulting instruction address: 0xc001bff0
  Oops: Kernel access of bad area, sig: 11 [#1]
  BE Canyonlands
  Modules linked in:
  CPU: 0 PID: 1 Comm: swapper Tainted: G        W
  4.18.0-rc6-00010-gff33d1030a6c #1
  NIP:  c001bff0 LR: c001c418 CTR: c01faa7c
  REGS: cf82db40 TRAP: 0300   Tainted: G        W
  (4.18.0-rc6-00010-gff33d1030a6c)
  MSR:  00029000 <CE,EE,ME>  CR: 28002024  XER: 00000000
  DEAR: 00000000 ESR: 00000000
  GPR00: c001c418 cf82dbf0 cf828000 cf8de400 00000000 00000000 000000c4 000000c4
  GPR08: c0481ea4 00000000 00000000 000000c4 22002024 00000000 c00025e8 00000000
  GPR16: 00000000 00000000 00000000 00000000 00000000 00000000 c0492380 0000004a
  GPR24: 00029000 0000000c 00000000 cf8de410 c0494d60 c0494d60 cf8bebc0 00000001
  NIP [c001bff0] ppc4xx_of_msi_remove+0x48/0xa0
  LR [c001c418] ppc4xx_msi_probe+0x294/0x3b8
  Call Trace:
  [cf82dbf0] [00029000] 0x29000 (unreliable)
  [cf82dc10] [c001c418] ppc4xx_msi_probe+0x294/0x3b8
  [cf82dc70] [c0209fbc] platform_drv_probe+0x40/0x9c
  [cf82dc90] [c0208240] driver_probe_device+0x2a8/0x350
  [cf82dcc0] [c0206204] bus_for_each_drv+0x60/0xac
  [cf82dcf0] [c0207e88] __device_attach+0xe8/0x160
  [cf82dd20] [c02071e0] bus_probe_device+0xa0/0xbc
  [cf82dd40] [c02050c8] device_add+0x404/0x5c4
  [cf82dd90] [c0288978] of_platform_device_create_pdata+0x88/0xd8
  [cf82ddb0] [c0288b70] of_platform_bus_create+0x134/0x220
  [cf82de10] [c0288bcc] of_platform_bus_create+0x190/0x220
  [cf82de70] [c0288cf4] of_platform_bus_probe+0x98/0xec
  [cf82de90] [c0449650] __machine_initcall_canyonlands_ppc460ex_device_probe+0x38/0x54
  [cf82dea0] [c0002404] do_one_initcall+0x40/0x188
  [cf82df00] [c043daec] kernel_init_freeable+0x130/0x1d0
  [cf82df30] [c0002600] kernel_init+0x18/0x104
  [cf82df40] [c000c23c] ret_from_kernel_thread+0x14/0x1c
  Instruction dump:
  90010024 813d0024 2f890000 83c30058 41bd0014 48000038 813d0024 7f89f800
  409d002c 813e000c 57ea103a 3bff0001 <7c69502e> 2f830000 419effe0 4803b26d
  ---[ end trace 8cf551077ecfc42a ]---

Fix it up. Specifically,

- Return valid error codes from ppc4xx_setup_pcieh_hw(), have it clean
  up after itself, and only access hardware after all possible error
  conditions have been handled.
- Use devm_kzalloc() instead of kzalloc() in ppc4xx_msi_probe()
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Commit 9c7b185a ("powernv/cpuidle: Parse dt idle properties into
global structure") parses dt idle states into structs, but never marks
them valid. This results in all idle states being lost.

Fixes: 9c7b185a ("powernv/cpuidle: Parse dt idle properties into global structure")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Akshay Adiga <akshay.adiga@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

EEH recovery currently fails on pSeries for some IOV capable PCI
devices, if CONFIG_PCI_IOV is on and the hypervisor doesn't provide
certain device tree properties for the device. (Found on an IOV
capable device using the ipr driver.)

Recovery fails in pci_enable_resources() at the check on r->parent,
because r->flags is set and r->parent is not.  This state is due to
sriov_init() setting the start, end and flags members of the IOV BARs
but the parent not being set later in
pseries_pci_fixup_iov_resources(), because the
"ibm,open-sriov-vf-bar-info" property is missing.

Correct this by zeroing the resource flags for IOV BARs when they
can't be configured (this is the same method used by sriov_init() and
__pci_read_base()).

VFs cleared this way can't be enabled later, because that requires
another device tree property, "ibm,number-of-configurable-vfs" as well
as support for the RTAS function "ibm_map_pes". These are all part of
hypervisor support for IOV and it seems unlikely that a hypervisor
would ever partially, but not fully, support it. (None are currently
provided by QEMU/KVM.)
Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Reviewed-by: Bryant G. Ly <bryantly@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

OPAL firmware provides the facility for some groups of sensors to be
enabled/disabled at runtime to give the user the option of using the
system resources for collecting these sensors or not.

For example, on POWER9 systems, the On Chip Controller (OCC) gathers
various system and chip level sensors and maintains their values in
main memory.

This patch provides support for enabling/disabling the sensor groups
like power, temperature, current and voltage.
Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
[stewart@linux.vnet.ibm.com: Commit message]
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Adds support to enable/disable a sensor group at runtime. This
can be used to select the sensor groups that needs to be copied to
main memory by OCC. Sensor groups like power, temperature, current,
voltage, frequency, utilization can be enabled/disabled at runtime.
Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Export pnv_idle_states and nr_pnv_idle_states so that its accessible to
cpuidle driver. Use properties from pnv_idle_states structure for powernv
cpuidle_init.
Signed-off-by: Akshay Adiga <akshay.adiga@linux.vnet.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Device-tree parsing happens twice, once while deciding idle state to be
used for hotplug and once during cpuidle init. Hence, parsing the device
tree and caching it will reduce code duplication. Parsing code has been
moved to pnv_parse_cpuidle_dt() from pnv_probe_idle_states(). In addition
to the properties in the device tree the number of available states is
also required.
Signed-off-by: Akshay Adiga <akshay.adiga@linux.vnet.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Some of the event counters are overloaded which makes it very
difficult to interpret their values.

Counter 0 is supposed to report CB1 interrupts but it can also count
PMU_INT_WAITING_CHARGER events.

Counter 1 is supposed to report GPIO interrupts but it can also count
other events (depending upon the value of the PMU_INT_ADB bit).

Disambiguate these statistics with dedicated counters for GPIO and
CB1 interrupts.

Comments in the MkLinux source code say that the type 0 and type 1
interrupts are model-specific. Label them as "unknown".

This change to the contents of /proc/pmu/interrupts is by necessity
visible in userland. However, packages which interact with the PMU
(that is, pbbuttonsd, pmac-utils and pmud) don't open this file.
AFAIK, user software has no need to poll these counters.
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Replace an open-coded ffs() with the function call.
Simplify an if-else cascade using a switch statement.
Correct a typo and an indentation issue.
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Now that the PowerMac via-pmu driver supports m68k PowerBooks,
switch over to that driver and remove the via-pmu68k driver.
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Don't load the via-pmu68k driver on early PowerBooks. The M50753 PMU
device found in those models was never supported by this driver.
Attempting to load the driver usually causes a boot hang.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Michael Schmitz <schmitzmic@gmail.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

At present, CONFIG_ADB_PMU depends on CONFIG_PPC_PMAC. When this gets
relaxed to CONFIG_PPC_PMAC || CONFIG_MAC, those Kconfig symbols with
implicit deps on PPC_PMAC will need explicit deps. Add them now.
No functional change.
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Put #ifdefs around the Open Firmware, xmon, interrupt dispatch,
battery and suspend code. Add the necessary interrupt handling to
support m68k PowerBooks.

The pmu_kind value is available to userspace using the
PMU_IOC_GET_MODEL ioctl. It is not clear yet what hardware classes
are be needed to describe m68k PowerBook models, so pmu_kind is given
the provisional value PMU_UNKNOWN.

To find out about the hardware, user programs can use /proc/bootinfo
or /proc/hardware, or send the PMU_GET_VERSION command using /dev/adb.
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

On most PowerPC Macs, the PMU driver uses the shift register and
IO port B from a single VIA chip.

On 68k and early PowerPC PowerBooks, the driver uses the shift register
from one VIA chip together with IO port B from another.

Replace via with via1 and via2 to accommodate this. For the
CONFIG_PPC_PMAC case, set via1 = via2 so there is no change.
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

On 68k Macs, the via/vias pointer can't be used to determine whether
the PMU driver has been initialized. For portability, add a new state
to indicate that via_find_pmu() succeeded.

After via_find_pmu() executes, testing vias == NULL is equivalent to
testing via == NULL. Replace these tests with pmu_state == uninitialized
which is simpler and more consistent. No functional change.
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The shift register interrupt flag gets cleared in via_pmu_interrupt()
and once again in pmu_sr_intr(). Fix this theoretical race condition.
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Add missing in_8() accessors to init_pmu() and pmu_sr_intr().

This fixes several sparse warnings:
drivers/macintosh/via-pmu.c:536:29: warning: dereference of noderef expression
drivers/macintosh/via-pmu.c:537:33: warning: dereference of noderef expression
drivers/macintosh/via-pmu.c:1455:17: warning: dereference of noderef expression
drivers/macintosh/via-pmu.c:1456:69: warning: dereference of noderef expression
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The pmu_init() function has the __init qualifier, but the ops struct
that holds a pointer to it does not. This causes a build warning.
The driver works fine because the pointer is only dereferenced early.

The function is so small that there's negligible benefit from using
the __init qualifier. Remove it to fix the warning, consistent with
the other ADB drivers.
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

mmu_init_secondary() calls ppc44x_pin_tlb() which is marked __init,
leading to a warning:

  The function mmu_init_secondary() references
  the function __init ppc44x_pin_tlb().

There's no CPU hotplug support on 44x so mmu_init_secondary() will
only be called at boot. Therefore we should mark it as __init.
Signed-off-by: Alexey Spirkov <alexeis@astrosoft.ru>
[mpe: Flesh out change log details]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>