Update the cpu dlpar add/remove paths to do better error recovery when
a failure occurs during the add/remove operation.
Signed-off-by: NNathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Re-factor the cpu hotplug code to support doing cpu hotplug completely in
the kernel and using the existing sysfs probe/release interfaces. This
patch pulls out pieces of existing cpu hotplug code into common routines,
dlpar_cpu_add() and dlpar_cpu_remove(), to be used by both interfaces.
There are no functional changes introduced.
Signed-off-by: NNathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

No functional changes, this patch is simply a move of the cpu hotplug
code from pseries/dlpar.c to pseries/hotplug-cpu.c. This is in an effort
to consolidate all of the cpu hotplug code in a common place.
Signed-off-by: NNathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

When DLPAR adding a CPU we should verify that the CPU does not already
exist. Failure to do so can generate a kernel oops;

[    9.465585] kernel BUG at arch/powerpc/platforms/pseries/dlpar.c:382!
[    9.465796] Oops: Exception in kernel mode, sig: 5 [#1]

This oops can be generated by causing a probe to be performed on a cpu
by writing to the sysfs cpu probe file (/sys/devices/system/cpu/probe).
This patch adds a check for the existence of cpu prior to probing the cpu
so userspace doing the wrong thing won't trigger a BUG_ON().
Signed-off-by: NNathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

PPC476FPE has a different PVR from previous PPC476 processors. The
kexec code checks the PVR in order to correctly setup the MMU. When
the initial support for 476FPE processors was added the corresponding
change in the kexec code was missed. This patch simply adds the check
and solves the following bug on kexec:

kexec: Starting new kernel
Bye!
Unable to handle kernel paging request for instruction fetch
Faulting instruction address: 0xee9a50f8
cpu 0x0: Vector: 400 (Instruction Access) at [ee9d7d20]
    pc: ee9a50f8
    lr: ee9a50e4
    sp: ee9d7dd0
    msr: 21020
    current = 0xee40f000
    pid   = 960, comm = kexec
enter ? for help
[link register   ] ee9a50e4
[ee9d7dd0] c0013748 default_machine_kexec+0x58/0x70 (unreliable)
[ee9d7df0] c0012f04 machine_kexec+0x34/0x40
[ee9d7e00] c00aa1ec kernel_kexec+0x9c/0xb0
[ee9d7e20] c005d704 SyS_reboot+0x1f4/0x220
[ee9d7f40] c000db68 ret_from_syscall+0x0/0x3c
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

NVLink is a high speed interconnect that is used in conjunction with a
PCI-E connection to create an interface between CPU and GPU that
provides very high data bandwidth. A PCI-E connection to a GPU is used
as the control path to initiate and report status of large data
transfers sent via the NVLink.

On IBM Power systems the NVLink processing unit (NPU) is similar to
the existing PHB3. This patch adds support for a new NPU PHB type. DMA
operations on the NPU are not supported as this patch sets the TCE
translation tables to be the same as the related GPU PCIe device for
each NVLink. Therefore all DMA operations are setup and controlled via
the PCIe device.

EEH is not presently supported for the NPU devices, although it may be
added in future.
Signed-off-by: NAlistair Popple <alistair@popple.id.au>
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Move __raw_rm_writeq() from platforms/powernv/pci-ioda.c to
include/asm/io.h so that it can be used by other code.
Signed-off-by: NAlistair Popple <alistair@popple.id.au>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This commit removed the pcidev field from struct pci_dn as it was no
longer in use by the kernel. However to support finding the
association of Nvlink devices to GPU devices from the device-tree this
field is required.

This reverts commit 250c7b27 ("powerpc/pci: Remove unused struct
pci_dn.pcidev field").
Signed-off-by: NAlistair Popple <alistair@popple.id.au>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The name of PCI root bus's M64 resource isn't initialized properly.
When dumping "/proc/iomem", "<BAD>" is seen for those M64 resources
on PCI root buses.

   ~# cat /proc/iomem | grep -e "BAD"
   3b0000000000-3b0fefffffff : <BAD>
   3b1000000000-3b1fefffffff : <BAD>
   3c0000000000-3c0fefffffff : <BAD>
   3c1000000000-3c1fefffffff : <BAD>
   3c2000000000-3c2fefffffff : <BAD>

This fixes the issue by setting the name of PCI root bus's M64
resource to that of PHB's device node full name. With the patch,
no "<BAD>" is seen from "/proc/iomem".
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

User space checkpoint and restart tool (CRIU) needs the page's change
to be soft tracked. This allows to do a pre checkpoint and then dump
only touched pages.

This is done by using a newly assigned PTE bit (_PAGE_SOFT_DIRTY) when
the page is backed in memory, and a new _PAGE_SWP_SOFT_DIRTY bit when
the page is swapped out.

To introduce a new PTE _PAGE_SOFT_DIRTY bit value common to hash 4k
and hash 64k pte, the bits already defined in hash-*4k.h should be
shifted left by one.

The _PAGE_SWP_SOFT_DIRTY bit is dynamically put after the swap type in
the swap pte. A check is added to ensure that the bit is not
overwritten by _PAGE_HPTEFLAGS.
Signed-off-by: NLaurent Dufour <ldufour@linux.vnet.ibm.com>
CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The STD_EXCEPTION_PSERIES macro takes both a vector number, and a
location (memory address). However both are always identical, so combine
them to save repeating ourselves.

This does mean an exception handler must always exist at the location in
memory that matches its vector number. But that's OK because this is the
"STD" macro (standard), which does exactly that. We have other macros
for the other cases, eg. STD_EXCEPTION_PSERIES_OOL (out of line).
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This is only used in one location, open code it.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

HMT_MEDIUM_LOW_HAS_PPR is only used in once place, open code it.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

HMT_MEDIUM_PPR_DISCARD is a macro which is present at the start of most
of our first level exception handlers. It conditionally executes a
HMT_MEDIUM instruction, which sets the processor priority to medium.

On on modern systems, ie. Power7 and later, it is nop'ed out at boot.
All it does is make the exception vectors more cramped, and consume 4
bytes of icache.

On old systems it has the effect of boosting the processor priority at
the start of exception processing. If we were previously in the idle
loop for example, we may be at low or very low priority. This is
desirable as we want to process the exception as fast as possible.

However looking closely at the generated code, we see that in all cases
we execute another HMT_MEDIUM just four instructions later. With code
patching applied, the final code on an old (Power6) system will look
like, eg:

  c000000000000300 <data_access_pSeries>:
  c000000000000300:	7c 42 13 78	mr	r2,r2		<-
  c000000000000304:	7d b2 43 a6	mtsprg	2,r13
  c000000000000308:	7d b1 42 a6	mfsprg	r13,1
  c00000000000030c:	f9 2d 00 80	std	r9,128(r13)
  c000000000000310:	60 00 00 00	nop
  c000000000000314:	7c 42 13 78	mr	r2,r2		<-

So I suggest that the added code complexity of HMT_MEDIUM_PPR_DISCARD is
not justified by the benefit of boosting the processor priority for the
duration of four instructions, and therefore we drop it.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

There are no longer any users of enter_rtas() outside of rtas.c, so make
it "private", by moving the declaration inside rtas.c. Hopefully this
will encourage people to use one of the wrappers which takes the sharp
edges off the RTAS calling sequence.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Although call_rtas_display_status() does actually want to use the
regular RTAS locking, it doesn't want the extra logic that is in
rtas_call(), so currently it open codes the logic.

Instead we can use rtas_call_unlocked(), after taking the RTAS lock.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Avoid open coding the logic by using rtas_call_unlocked().
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Avoid open coding the logic by using rtas_call_unlocked().
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Most users of RTAS (Run-Time Abstraction Services) use rtas_call(),
which deals with locking as well as endian handling.

However we have two users outside of rtas.c that can't use rtas_call()
because they have different locking requirements.

The hotplug CPU code can't take the RTAS lock because the CPU would go
offline with the lock held and no other CPUs would be able to call RTAS
until the CPU came back online.

The xmon code doesn't want to take the lock because it would risk dead
locking when we are trying to recover from a crash.

Both sites required multiple patches when we added little endian
support, proving that programmers can't do endian right.

Although that ship has sailed, we can still clean the code up by
providing an unlocked version of rtas_call() which avoids the need to
open code the logic elsewhere.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Long ago, only in the lab, there was OPALv1 and OPALv2. Now there is
just OPALv3, with nobody ever expecting anything on pre-OPALv3 to
be cared about or supported by mainline kernels.

So, let's remove FW_FEATURE_OPALv3 and instead use FW_FEATURE_OPAL
exclusively.
Signed-off-by: NStewart Smith <stewart@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

OPALv2 only ever existed in the lab and didn't escape to the world.
All OPAL systems in the wild are OPALv3.

The probability of there being an OPALv2 system still powered on
anywhere inside IBM is approximately zero, let alone anyone
expecting to run mainline kernels.

So, start to remove references to OPALv2.
Signed-off-by: NStewart Smith <stewart@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The OpenPower Abstraction Layer firmware went through a couple
of iterations in the lab before being released. What we now know
as OPAL advertises itself as OPALv3.

OPALv2 and OPALv1 never made it outside the lab, and the possibility
of anyone at all ever building a mainline kernel today and expecting
it to boot on such hardware is zero.
Signed-off-by: NStewart Smith <stewart@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

HMIs (Hypervisor Management|Maintenance Interrupts) are a class of interrupt
on POWER systems.

HMI support has traditionally been exceptionally difficult to test, however
Skiboot ships a tool that, with the correct magic numbers, will inject them.

This, therefore, is a first pass at a script to inject HMIs and monitor
Linux's response. It injects an HMI on each core on every chip in turn
It then watches dmesg to see if it's acknowledged by Linux.

On a Tuletta, I observed that we see 8 (or sometimes 9 or more) events per
injection, regardless of SMT setting, so we wait for 8 before progressing.

It sits in a new scripts/ directory in selftests/powerpc, because it's not
designed to be run as part of the regular make selftests process. In
particular, it is quite possibly going to end up garding lots of your CPUs,
so it should only be run if you know how to undo that.

CC: Mahesh J Salgaonkar <mahesh.salgaonkar@in.ibm.com>
Signed-off-by: NDaniel Axtens <dja@axtens.net>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Simply because it touches more code paths that way, and therefore tests
more things.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Acked-by: NAnton Blanchard <anton@samba.org>

For ease of use make the context_switch test do something useful when
called with no arguments.

Default to a 30 second run, using threads, doing yield, and use any
online cpu. Make it print out what it's doing to avoid confusion.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Acked-by: NAnton Blanchard <anton@samba.org>

This gets referred to a lot in commit messages, so let's pull it into
the selftests.

Almost vanilla from: http://ozlabs.org/~anton/junkcode/context_switch2.cSigned-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Acked-by: NAnton Blanchard <anton@samba.org>

We want to use this in another test, so make it available at the top of
the powerpc selftests tree.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

GregorianDay() is supposed to calculate the day of the week
(tm->tm_wday) for a given day/month/year. In that calcuation it
indexed into an array called MonthOffset using tm->tm_mon-1. However
tm_mon is zero-based, not one-based, so this is off-by-one. It also
means that every January, GregoiranDay() will access element -1 of
the MonthOffset array.

It also doesn't appear to be a correct algorithm either: see in
contrast kernel/time/timeconv.c's time_to_tm function.

It's been broken forever, which suggests no-one in userland uses
this. It looks like no-one in the kernel uses tm->tm_wday either
(see e.g. drivers/rtc/rtc-ds1305.c:319).

tm->tm_wday is conventionally set to -1 when not available in
hardware so we can simply set it to -1 and drop the function.
(There are over a dozen other drivers in drivers/rtc that do
this.)

Found using UBSAN.

Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andrew Morton <akpm@linux-foundation.org> # as an example of what UBSan finds.
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: rtc-linux@googlegroups.com
Signed-off-by: NDaniel Axtens <dja@axtens.net>
Acked-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

When a transaction is aborted, VSR values should rollback to the
checkpointed values before the transaction began. VSRs used elsewhere in
the kernel during a transaction, or while the transaction is suspended
should not affect the checkpointed values.

Prior to the bug fix in commit d31626f7 ("powerpc: Don't corrupt
transactional state when using FP/VMX in kernel") when VMX was requested
by the kernel the .vr_state (which held the checkpointed state of VSRs
before the transaction) was overwritten with the current state from
outside the transation. Thus if the transaction did not complete, the
VSR values would be "rolled back" to potentially incorrect values.
Signed-off-by: NRashmica Gupta <rashmicy@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Currently if you are in xmon without an oops etc. to view the kernel
version you have to type "d $linux_banner" - not necessarily obvious. As
this is useful information, append to the output of "e" command.

Example output:
  $mon> e
  cpu 0x1: Vector: 0  at [c0000000f879ba80]
      pc: c000000000081718: sysrq_handle_xmon+0x68/0x80
      lr: c000000000081718: sysrq_handle_xmon+0x68/0x80
      sp: c0000000f879bbe0
     msr: 8000000000009033
    current = 0xc0000000f604d5c0
    paca    = 0xc00000000fdc0480	 softe: 0	 irq_happened: 0x01
      pid   = 2467, comm = bash
  Linux version 4.4.0-rc2-00008-gc51af91c3ab3-dirty (rashmica@circle) (gcc
  version 5.1.1 20150629 (GCC) ) #45 SMP Wed Nov 25 10:25:12 AEDT 2015
Signed-off-by: NRashmica Gupta <rashmicy@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

All users of QPACE have upgraded to QPACE2 so remove the Cell QPACE code.
Signed-off-by: NRashmica Gupta <rashmicy@gmail.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Kernel prints respective warnings about various EPOW events for
user information/action after parsing EPOW interrupts. At times
below EPOW reset event warning is seen to be flooding kernel log
over a period of time.

May 25 03:46:34 alp kernel: Non critical power or cooling issue cleared
May 25 03:46:52 alp kernel: Non critical power or cooling issue cleared
May 25 03:53:48 alp kernel: Non critical power or cooling issue cleared
May 25 03:55:46 alp kernel: Non critical power or cooling issue cleared
May 25 03:56:34 alp kernel: Non critical power or cooling issue cleared
May 25 03:59:04 alp kernel: Non critical power or cooling issue cleared
May 25 04:02:01 alp kernel: Non critical power or cooling issue cleared

These EPOW reset events are spurious in nature and are triggered by
firmware without an actual EPOW event being reset. This patch avoids these
multiple EPOW reset warnings by using a counter variable. This variable
is incremented every time an EPOW event is reported. Upon receiving a EPOW
reset event the same variable is checked to filter out spurious events and
decremented accordingly.

This patch also improves log messages to better describe EPOW event being
reported. Merged adjacent log messages into single one to reduce number of
lines printed per event.
Signed-off-by: NKamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: NVipin K Parashar <vipin@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Test the kernels signal generation code to ensure it can handle an
invalid stack pointer when transactional.
Signed-off-by: NMichael Neuling <mikey@neuling.org>
Tested-by: NAnshuman Khandual <khandual@linux.vnet.ibm.com>
[mpe: Skip if we don't have TM]
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Test the kernel's signal return code to ensure that it doesn't crash
when both the transactional and suspend MSR bits are set in the signal
context.
Signed-off-by: NMichael Neuling <mikey@neuling.org>
Tested-by: NAnshuman Khandual <khandual@linux.vnet.ibm.com>
[mpe: Skip if we don't have TM]
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Move have_htm_nosc() into a new tm.h, and add a new helper, have_htm()
which we'll use in the next patch.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

We already do this twice and want to add another so add a helper.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This doesn't really belong in harness.c, it's a helper function. So move
it into utils.c.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Merge the two TM fixes we merged in 4.4. We are about to merge selftests
for these, and without the fixes the selftests will oops.

powerpc fixes for 4.4 #2

 - tm: Block signal return from setting invalid MSR state from Michael Neuling
 - tm: Check for already reclaimed tasks from Michael Neuling

Print MSR TM bits in oops messages.  This appends them to the end
like this:

    MSR: 8000000502823031 <SF,VEC,VSX,FP,ME,IR,DR,LE,TM[TE]>

You get the TM[] only if at least one TM MSR bit is set.  Inside the
TM[], E means Enabled (bit 32), S means Suspended (bit 33), and T
means Transactional (bit 34)

If no bits are set, you get no TM[] output.

Include rework of printbits() to handle this case.
Signed-off-by: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>