Commit Graph

738376 Commits

Author SHA1 Message Date
Logan Gunthorpe
07c3d9eaa4 powerpc: iomap.c: introduce io{read|write}64_{lo_hi|hi_lo}
These functions will be introduced into the generic iomap.c so they
can deal with PIO accesses in hi-lo/lo-hi variants. Thus, the powerpc
version of iomap.c will need to provide the same functions even
though, in this arch, they are identical to the regular
io{read|write}64 functions.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Tested-by: Horia Geantă <horia.geanta@nxp.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-05 14:59:26 +10:00
Logan Gunthorpe
ef237039c5 powerpc: io.h: move iomap.h include so that it can use readq/writeq defs
Subsequent patches in this series makes use of the readq and writeq
defines in iomap.h. However, as is, they get missed on the powerpc
platform seeing the include comes before the define. This patch moves
the include down to fix this.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-05 14:58:52 +10:00
Frederic Barrat
ad7b4e8022 cxl: Fix possible deadlock when processing page faults from cxllib
cxllib_handle_fault() is called by an external driver when it needs to
have the host resolve page faults for a buffer. The buffer can cover
several pages and VMAs. The function iterates over all the pages used
by the buffer, based on the page size of the VMA.

To ensure some stability while processing the faults, the thread T1
grabs the mm->mmap_sem semaphore with read access (R1). However, when
processing a page fault for a single page, one of the underlying
functions, copro_handle_mm_fault(), also grabs the same semaphore with
read access (R2). So the thread T1 takes the semaphore twice.

If another thread T2 tries to access the semaphore in write mode W1
(say, because it wants to allocate memory and calls 'brk'), then that
thread T2 will have to wait because there's a reader (R1). If the
thread T1 is processing a new page at that time, it won't get an
automatic grant at R2, because there's now a writer thread
waiting (T2). And we have a deadlock.

The timeline is:
1. thread T1 owns the semaphore with read access R1
2. thread T2 requests write access W1 and waits
3. thread T1 requests read access R2 and waits

The fix is for the thread T1 to release the semaphore R1 once it got
the information it needs from the current VMA. The address space/VMAs
could evolve while T1 iterates over the full buffer, but in the
unlikely case where T1 misses a page, the external driver will raise a
new page fault when retrying the memory access.

Fixes: 3ced8d7300 ("cxl: Export library to support IBM XSL")
Cc: stable@vger.kernel.org # 4.13+
Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-04 22:09:33 +10:00
Naveen N. Rao
5d6a03ebc8 powerpc/hw_breakpoint: Only disable hw breakpoint if cpu supports it
We get the below warning if we try to use kexec on P9:
   kexec_core: Starting new kernel
   WARNING: CPU: 0 PID: 1223 at arch/powerpc/kernel/process.c:826 __set_breakpoint+0xb4/0x140
   [snip]
   NIP __set_breakpoint+0xb4/0x140
   LR  kexec_prepare_cpus_wait+0x58/0x150
   Call Trace:
     0xc0000000ee70fb20 (unreliable)
     0xc0000000ee70fb20
     default_machine_kexec+0x234/0x2c0
     machine_kexec+0x84/0x90
     kernel_kexec+0xd8/0xe0
     SyS_reboot+0x214/0x2c0
     system_call+0x58/0x6c

This happens since we are trying to clear hw breakpoint on POWER9,
though we don't have CPU_FTR_DAWR enabled. Guard __set_breakpoint()
within hw_breakpoint_disable() with ppc_breakpoint_available() to
address this.

Fixes: 9654153158 ("powerpc: Disable DAWR in the base POWER9 CPU features")
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-04 21:54:02 +10:00
Aneesh Kumar K.V
7a22d6321c powerpc/mm/radix: Update command line parsing for disable_radix
kernel parameter disable_radix takes different options
disable_radix=yes|no|1|0  or just disable_radix.

prom_init parsing is not supporting these options.

Fixes: 1fd6c02207 ("powerpc/mm: Add a CONFIG option to choose if radix is used by default")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-04 16:59:50 +10:00
Aneesh Kumar K.V
cec4e9b28f powerpc/mm/radix: Parse disable_radix commandline correctly.
kernel parameter disable_radix takes different options
disable_radix=yes|no|1|0 or just disable_radix. When using the later
format we get below error.

 `Malformed early option 'disable_radix'`

Fixes: 1fd6c02207 ("powerpc/mm: Add a CONFIG option to choose if radix is used by default")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-04 16:59:36 +10:00
Aneesh Kumar K.V
6fa504835d powerpc/mm/hugetlb: initialize the pagetable cache correctly for hugetlb
With 64k page size, we have hugetlb pte entries at the pmd and pud level for
book3s64. We don't need to create a separate page table cache for that. With 4k
we need to make sure hugepd page table cache for 16M is placed at PUD level
and 16G at the PGD level.

Simplify all these by not using HUGEPD_PD_SHIFT which is confusing for book3s64.

Without this patch, with 64k page size we create pagetable caches with shift
value 10 and 7 which are not used at all.

Fixes: 419df06eea ("powerpc: Reduce the PTE_INDEX_SIZE")

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-04 16:58:53 +10:00
Aneesh Kumar K.V
fb4e5dbd44 powerpc/mm/radix: Update pte fragment count from 16 to 256 on radix
With split PTL (page table lock) config, we allocate the level
4 (leaf) page table using pte fragment framework instead of slab cache
like other levels. This was done to enable us to have split page table
lock at the level 4 of the page table. We use page->plt backing the
all the level 4 pte fragment for the lock.

Currently with Radix, we use only 16 fragments out of the allocated
page. In radix each fragment is 256 bytes which means we use only 4k
out of the allocated 64K page wasting 60k of the allocated memory.
This was done earlier to keep it closer to hash.

This patch update the pte fragment count to 256, thereby using the
full 64K page and reducing the memory usage. Performance tests shows
really low impact even with THP disabled. With THP disabled we will be
contenting further less on level 4 ptl and hence the impact should be
further low.

  256 threads:
    without patch (10 runs of ./ebizzy  -m -n 1000 -s 131072 -S 100)
      median = 15678.5
      stdev = 42.1209

    with patch:
      median = 15354
      stdev = 194.743

This is with THP disabled. With THP enabled the impact of the patch
will be less.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-04 16:58:06 +10:00
Aneesh Kumar K.V
f2ed480fa4 powerpc/mm/keys: Update documentation and remove unnecessary check
Adds more code comments. We also remove an unnecessary pkey check
after we check for pkey error in this patch.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-04 15:23:09 +10:00
Nicholas Piggin
b9ee31e100 powerpc/64s/idle: POWER9 ESL=0 stop avoid save/restore overhead
When stop is executed with EC=ESL=0, it appears to execute like a
normal instruction (resuming from NIP when woken by interrupt). So all
the save/restore handling can be avoided completely. In particular NV
GPRs do not have to be saved, and MSR does not have to be switched
back to kernel MSR.

So move the test for EC=ESL=0 sleep states out to power9_idle_stop,
and return directly to the caller after stop in that case.

This improves performance for ping-pong benchmark with the stop0_lite
idle state by 2.54% for 2 threads in the same core, and 2.57% for
different cores. Performance increase with HV_POSSIBLE defined will be
improved further by avoiding the hwsync.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-04 11:11:43 +10:00
Michael Ellerman
d0b791c029 powerpc/64s/idle: Consolidate power9_offline_stop()/power9_idle_stop()
Commit 3d4fbffdd7 ("powerpc/64s/idle: POWER9 implement a separate
idle stop function for hotplug") that added power9_offline_stop() was
written before commit 7672691a08 ("powerpc/powernv: Provide a way to
force a core into SMT4 mode").

When merging the former I failed to notice that it caused us to skip
the force-SMT4 logic for offline CPUs. The result is that offlined
CPUs will not correctly participate in the force-SMT4 logic, which
presumably will result in badness (not tested).

Reconcile the two commits by making power9_offline_stop() a pre-cursor
to power9_idle_stop(), so that they share the force-SMT4 logic.

This is based on an original commit from Nick, all breakage is my own.

Fixes: 3d4fbffdd7 ("powerpc/64s/idle: POWER9 implement a separate idle stop function for hotplug")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
2018-04-04 09:09:35 +10:00
Nicholas Piggin
f2748bdfe1 powerpc/powernv: Always stop secondaries before reboot/shutdown
Currently powernv reboot and shutdown requests just leave secondaries
to do their own things. This is undesirable because they can trigger
any number of watchdogs while waiting for reboot, but also we don't
know what else they might be doing -- they might be causing trouble,
trampling memory, etc.

The opal scheduled flash update code already ran into watchdog problems
due to flashing taking a long time, and it was fixed with 2196c6f1ed
("powerpc/powernv: Return secondary CPUs to firmware before FW update"),
which returns secondaries to opal. It's been found that regular reboots
can take over 10 seconds, which can result in the hard lockup watchdog
firing,

  reboot: Restarting system
  [  360.038896709,5] OPAL: Reboot request...
  Watchdog CPU:0 Hard LOCKUP
  Watchdog CPU:44 detected Hard LOCKUP other CPUS:16
  Watchdog CPU:16 Hard LOCKUP
  watchdog: BUG: soft lockup - CPU#16 stuck for 3s! [swapper/16:0]

This patch removes the special case for flash update, and calls
smp_send_stop in all cases before calling reboot/shutdown.

smp_send_stop could return CPUs to OPAL, the main reason not to is
that the request could come from a NMI that interrupts OPAL code,
so re-entry to OPAL can cause a number of problems. Putting
secondaries into simple spin loops improves the chances of a
successful reboot.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by:  Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-03 22:59:57 +10:00
Nicholas Piggin
855bfe0de1 powerpc: hard disable irqs in smp_send_stop loop
The hard lockup watchdog can fire under local_irq_disable
on platforms with irq soft masking.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-03 22:59:10 +10:00
Nicholas Piggin
6bed323762 powerpc: use NMI IPI for smp_send_stop
Use the NMI IPI rather than smp_call_function for smp_send_stop.
Have stopped CPUs hard disable interrupts rather than just soft
disable.

This function is used in crash/panic/shutdown paths to bring other
CPUs down as quickly and reliably as possible, and minimizing their
potential to cause trouble.

Avoiding the Linux smp_call_function infrastructure and (if supported)
using true NMI IPIs makes this more robust.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-03 22:59:09 +10:00
Nicholas Piggin
a2b5e056b7 powerpc/powernv: Fix SMT4 forcing idle code
The PSSCR value is not stored to PACA_REQ_PSSCR if the CPU does not
have the XER[SO] bug.

Fix this by storing up-front, outside the workaround code. The initial
test is not required because it is a slow path.

The workaround is made to depend on CONFIG_KVM_BOOK3S_HV_POSSIBLE, to
match pnv_power9_force_smt4_catch() where it is used. Drop the comment
on pnv_power9_force_smt4_catch() as it's no longer true.

Fixes: 7672691a08 ("powerpc/powernv: Provide a way to force a core into SMT4 mode")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-03 22:14:27 +10:00
Michael Ellerman
b6f534d1a6 selftests/powerpc: Fix copyloops build since Power4 assembler change
The recent commit 15a3204d24 ("powerpc/64s: Set assembler machine
type to POWER4") set the machine type in our ASFLAGS when building the
kernel, and removed some ".machine power4" directives from various asm
files.

This broke the selftests build on old toolchains (that don't assume
Power4), because we build the kernel source files into the selftests
using different ASFLAGS.

The fix is simply to add -mpower4 to the selftest ASFLAGS as well.

Fixes: 15a3204d24 ("powerpc/64s: Set assembler machine type to POWER4")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-03 21:50:09 +10:00
Mauricio Faria de Oliveira
6232774f15 powerpc/pseries: Restore default security feature flags on setup
After migration the security feature flags might have changed (e.g.,
destination system with unpatched firmware), but some flags are not
set/clear again in init_cpu_char_feature_flags() because it assumes
the security flags to be the defaults.

Additionally, if the H_GET_CPU_CHARACTERISTICS hypercall fails then
init_cpu_char_feature_flags() does not run again, which potentially
might leave the system in an insecure or sub-optimal configuration.

So, just restore the security feature flags to the defaults assumed
by init_cpu_char_feature_flags() so it can set/clear them correctly,
and to ensure safe settings are in place in case the hypercall fail.

Fixes: f636c14790 ("powerpc/pseries: Set or clear security feature flags")
Depends-on: 19887d6a28e2 ("powerpc: Move default security feature flags")
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-03 21:50:09 +10:00
Mauricio Faria de Oliveira
e7347a8683 powerpc: Move default security feature flags
This moves the definition of the default security feature flags
(i.e., enabled by default) closer to the security feature flags.

This can be used to restore current flags to the default flags.

Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-03 21:50:08 +10:00
Nicholas Piggin
252988cbf0 powerpc: Don't write to DABR on >= Power8 if DAWR is disabled
flush_thread() calls __set_breakpoint() via set_debug_reg_defaults()
without checking ppc_breakpoint_available(). On Power8 or later CPUs
which have the DAWR feature disabled that will cause a write to the
DABR which is incorrect as those CPUs don't have a DABR.

Fix it two ways, by checking ppc_breakpoint_available() in
set_debug_reg_defaults(), and also by reworking __set_breakpoint() to
only write to DABR on Power7 or earlier.

Fixes: 9654153158 ("powerpc: Disable DAWR in the base POWER9 CPU features")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Rework the logic in __set_breakpoint()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-03 21:50:08 +10:00
Nicholas Piggin
e303c08787 KVM: PPC: Book3S HV: Fix ppc_breakpoint_available compile error
arch/powerpc/kvm/book3s_hv.c: In function ‘kvmppc_h_set_mode’:
arch/powerpc/kvm/book3s_hv.c:745:8: error: implicit declaration of function ‘ppc_breakpoint_available’
   if (!ppc_breakpoint_available())
        ^~~~~~~~~~~~~~~~~~~~~~~~

Fixes: 398e712c00 ("KVM: PPC: Book3S HV: Return error from h_set_mode(SET_DAWR) on POWER9")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-03 21:50:07 +10:00
Aneesh Kumar K.V
a6201da34f powerpc: Fix oops due to bad access of lppaca on bare metal
Commit 8e0b634b13 ("powerpc/64s: Do not allocate lppaca if we are
not virtualized") removed allocation of lppaca on bare metal
platforms. But with CONFIG_PPC_SPLPAR enabled, we still access the
lppaca on bare metal in some code paths.

Fix this but adding runtime checks for SPLPAR (shared processor LPAR).

Fixes: 8e0b634b13 ("powerpc/64s: Do not allocate lppaca if we are not virtualized")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-03 21:50:07 +10:00
Mathieu Malaterre
19e68b2aec powerpc/mm/radix: Fix always false comparison against MMU_NO_CONTEXT
In commit 9690c15742 ("powerpc/mm/radix: Fix always false comparison
against MMU_NO_CONTEXT") an issue was discovered where `mm->context.id` was
being truncated to an `unsigned int`, while the PID is actually an
`unsigned long`. Update the earlier patch by fixing one remaining
occurrence. Discovered during a compilation with W=1:

  arch/powerpc/mm/tlb-radix.c:702:19: error: comparison is always false due to limited range of data type [-Werror=type-limits]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 22:15:34 +10:00
Matt Evans
0e524e761f powerpc: Clear branch trap (MSR.BE) before delivering SIGTRAP
When using SIG_DBG_BRANCH_TRACING, MSR.BE is left enabled in the
user context when single_step_exception() prepares the SIGTRAP
delivery.  The resulting branch-trap-within-the-SIGTRAP-handler
isn't healthy.

Commit 2538c2d08f broke this, by
replacing an MSR mask operation of ~(MSR_SE | MSR_BE) with a call
to clear_single_step() which only clears MSR_SE.

This patch adds a new helper, clear_br_trace(), which clears the
debug trap before invoking the signal handler.  This helper is a
NOP for BookE as SIG_DBG_BRANCH_TRACING isn't supported on BookE.

Signed-off-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 22:15:33 +10:00
Nicholas Piggin
4b7e5532d2 powerpc/64s: Add POWER9 CPU type selection
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 22:15:32 +10:00
Nicholas Piggin
db5ae1c155 powerpc/64s: Refine feature sets for little endian builds
This reduces vmlinux text size by 1kB and data by 1.5kB with a small
build!

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Add the recently added CPU_FTRS_POWER9_DD2_2 to the little
      endian possible mask as noticed by Nick.]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 22:14:40 +10:00
Nicholas Piggin
a73657ea19 powerpc/64: Add GENERIC_CPU support for little endian
Add GENERIC_CPU support for little-endian rather than using POWER8
specific selection for POWER9 and above.

Restrict GENERIC_CPU to POWER8 and above on little endian.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Duplicate GENERIC_CPU to avoid a kbuild warning about the prompt
      being redefined. Spell out that GENERIC means >= POWER4 for BE.]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 21:52:52 +10:00
Nicholas Piggin
471d7ff8b5 powerpc/64s: Remove POWER4 support
POWER4 has been broken since at least the change 49d09bf2a6
("powerpc/64s: Optimise MSR handling in exception handling"), which
requires mtmsrd L=1 support. This was introduced in ISA v2.01, and
POWER4 supports ISA v2.00.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:50 +11:00
Nicholas Piggin
3735eb850e powerpc: Remove unused CPU_FTR_ARCH_201
The last usage was removed in c17b98cf60 ("KVM: PPC: Book3S HV:
Remove code for PPC970 processors") (Dec 2014).

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:50 +11:00
Nicholas Piggin
9e9626ed3a powerpc/64s: Fix POWER9 DD2.2 and above in DT CPU features
The CPU_FTR_POWER9_DD2_1 flag is intended to be set for DD2.1 and
above (which is what the cputable setup does). Fix DT CPU features
quirk setup to match.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Merge with upstream changes]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:49 +11:00
Nicholas Piggin
15a3204d24 powerpc/64s: Set assembler machine type to POWER4
Rather than override the machine type in .S code (which can hide wrong
or ambiguous code generation for the target), set the type to power4
for all assembly.

This also means we need to be careful not to build power4-only code
when we're not building for Book3S, such as the "power7" versions of
copyuser/page/memcpy.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Fix Book3E build, don't build the "power7" variants for non-Book3S]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:49 +11:00
Nicholas Piggin
d50614fa45 powerpc/64s: Explicitly add vector features to CPU_FTRS_POSSIBLE
ALTIVEC and VSX features are not added by to default to the POWERx CPU
feature sets because they are intended to be enabled by firmware.
Currently they end up in CPU_FTRS_POSSIBLE due to their inclusion in
other the set for other CPUs, eg. PPC970.

But they should be added individually to the CPU_FTRS_POSSIBLE set,
because if we reduce the set of CPUs that are built-for they may
disappear from the possible mask.

It already contains CPU_FTR_VSX, so add ALTIVEC. The _COMP features
should be used because they won't be present if compiled out.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Add detail to change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:48 +11:00
Nicholas Piggin
b842bd0f7a powerpc/64s: Add all POWER9 features to CPU_FTRS_ALWAYS
It's not a bug to have features missing in CPU_FTR_ALWAYS, but it is a
missed opportunity for optimisation.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:48 +11:00
Mark Greer
147704534e powerpc/boot: Remove duplicate typedefs from libfdt_env.h
When building a uImage or zImage using ppc6xx_defconfig and some other
defconfigs, the following error occurs with GCC 4.5.1:

  /arch/powerpc/boot/libfdt_env.h:10:13: error: redefinition of typedef 'uint32_t'
  /arch/powerpc/boot/types.h:21:13: note: previous declaration of 'uint32_t' was here
  /arch/powerpc/boot/libfdt_env.h:11:13: error: redefinition of typedef 'uint64_t'
  /arch/powerpc/boot/types.h:22:13: note: previous declaration of 'uint64_t' was here

The problem is that commit 656ad58ef1 (powerpc/boot: Add OPAL
console to epapr wrappers) adds typedefs for uint32_t and uint64_t to
type.h but doesn't remove the pre-existing (and now duplicate)
typedefs from libfdt_env.h.

Fix the error by removing the duplicate typedefs from libfdt_env.h

Signed-off-by: Mark Greer <mgreer@animalcreek.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:47 +11:00
Nicholas Piggin
8c1c7fb0b5 powerpc/64s/idle: avoid sync for KVM state when waking from idle
When waking from a CPU idle instruction (e.g., nap or stop), the sync
for ordering the KVM secondary thread state can be avoided if there
wakeup is coming from a kernel context rather than KVM context.

This improves performance for ping-pong benchmark with the stop0 idle
state by 0.46% for 2 threads in the same core, and 1.02% for different
cores.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:47 +11:00
Nicholas Piggin
3d4fbffdd7 powerpc/64s/idle: POWER9 implement a separate idle stop function for hotplug
Implement a new function to invoke stop, power9_offline_stop, which is
like power9_idle_stop but used by the cpu hotplug code.

Move KVM secondary state manipulation code to the offline case.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:46 +11:00
Nicholas Piggin
d40b6768e4 powerpc/64s: sreset panic if there is no debugger or crash dump handlers
system_reset_exception does most of its own crash handling now,
invoking the debugger or crash dumps if they are registered. If not,
then it goes through to die() to print stack traces, and then is
supposed to panic (according to comments).

However after die() prints oopses, it does its own handling which
doesn't allow system_reset_exception to panic (e.g., it may just
kill the current process). This patch causes sreset exceptions to
return from die after it prints messages but before acting.

This also stops die from invoking the debugger on 0x100 crashes.
system_reset_exception similarly calls the debugger. It had been
thought this was harmless (because if the debugger was disabled,
neither call would fire, and if it was enabled the first call
would return). However in some cases like xmon 'X' command, the
debugger returns 0, which currently causes it to be entered
again (first in system_reset_exception, then in die), which is
confusing.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:46 +11:00
Nicholas Piggin
15b4dd7981 powerpc/64s: return more carefully from sreset NMI
System Reset, being an NMI, must return more carefully than other
interrupts. It has traditionally returned via the nromal return
from exception path, but that has a number of problems.

- r13 does not get restored if returning to kernel. This is for
  interrupts which may cause a context switch, which sreset will
  never do. Interrupting OPAL (which uses a different r13) is one
  place where this causes breakage.

- It may cause several other problems returning to kernel with
  preempt or TIF_EMULATE_STACK_STORE if it hits at the wrong time.

It's safer just to have a simple restore and return, like machine
check which is the other NMI.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:45 +11:00
Michael Neuling
f0295e047f powerpc/eeh: Fix race with driver un/bind
The current EEH callbacks can race with a driver unbind. This can
result in a backtraces like this:

  EEH: Frozen PHB#0-PE#1fc detected
  EEH: PE location: S000009, PHB location: N/A
  CPU: 2 PID: 2312 Comm: kworker/u258:3 Not tainted 4.15.6-openpower1 #2
  Workqueue: nvme-wq nvme_reset_work [nvme]
  Call Trace:
    dump_stack+0x9c/0xd0 (unreliable)
    eeh_dev_check_failure+0x420/0x470
    eeh_check_failure+0xa0/0xa4
    nvme_reset_work+0x138/0x1414 [nvme]
    process_one_work+0x1ec/0x328
    worker_thread+0x2e4/0x3a8
    kthread+0x14c/0x154
    ret_from_kernel_thread+0x5c/0xc8
  nvme nvme1: Removing after probe failure status: -19
  <snip>
  cpu 0x23: Vector: 300 (Data Access) at [c000000ff50f3800]
      pc: c0080000089a0eb0: nvme_error_detected+0x4c/0x90 [nvme]
      lr: c000000000026564: eeh_report_error+0xe0/0x110
      sp: c000000ff50f3a80
     msr: 9000000000009033
     dar: 400
   dsisr: 40000000
    current = 0xc000000ff507c000
    paca    = 0xc00000000fdc9d80   softe: 0        irq_happened: 0x01
      pid   = 782, comm = eehd
  Linux version 4.15.6-openpower1 (smc@smc-desktop) (gcc version 6.4.0 (Buildroot 2017.11.2-00008-g4b6188e)) #2 SM                                             P Tue Feb 27 12:33:27 PST 2018
  enter ? for help
    eeh_report_error+0xe0/0x110
    eeh_pe_dev_traverse+0xc0/0xdc
    eeh_handle_normal_event+0x184/0x4c4
    eeh_handle_event+0x30/0x288
    eeh_event_handler+0x124/0x170
    kthread+0x14c/0x154
    ret_from_kernel_thread+0x5c/0xc8

The first part is an EEH (on boot), the second half is the resulting
crash. nvme probe starts the nvme_reset_work() worker thread. This
worker thread starts touching the device which see a device error
(EEH) and hence queues up an event in the powerpc EEH worker
thread. nvme_reset_work() then continues and runs
nvme_remove_dead_ctrl_work() which results in unbinding the driver
from the device and hence releases all resources. At the same time,
the EEH worker thread starts doing the EEH .error_detected() driver
callback, which no longer works since the resources have been freed.

This fixes the problem in the same way the generic PCIe AER code (in
drivers/pci/pcie/aer/aerdrv_core.c) does. It makes the EEH code hold
the device_lock() while performing the driver EEH callbacks and
associated code. This ensures either the callbacks are no longer
register, or if they are registered the driver will not be removed
from underneath us.

This has been broken forever. The EEH call backs were first introduced
in 2005 (in 77bd741561) but it's not clear if a lock was needed back
then.

Fixes: 77bd741561 ("[PATCH] powerpc: PCI Error Recovery: PPC64 core recovery routines")
Cc: stable@vger.kernel.org # v2.6.16+
Signed-off-by: Michael Neuling <mikey@neuling.org>
Reviewed-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:45 +11:00
Thiago Jung Bauermann
bf8a1abc3d powerpc/kexec_file: Fix error code when trying to load kdump kernel
kexec_file_load() on powerpc doesn't support kdump kernels yet, so it
returns -ENOTSUPP in that case.

I've recently learned that this errno is internal to the kernel and
isn't supposed to be exposed to userspace. Therefore, change to
-EOPNOTSUPP which is defined in an uapi header.

This does indeed make kexec-tools happier. Before the patch, on
ppc64le:

  # ~bauermann/src/kexec-tools/build/sbin/kexec -s -p /boot/vmlinuz
  kexec_file_load failed: Unknown error 524

After the patch:

  # ~bauermann/src/kexec-tools/build/sbin/kexec -s -p /boot/vmlinuz
  kexec_file_load failed: Operation not supported

Fixes: a0458284f0 ("powerpc: Add support code for kexec_file_load()")
Cc: stable@vger.kernel.org # v4.10+
Reported-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Reviewed-by: Simon Horman <horms@verge.net.au>
Reviewed-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:44 +11:00
Jonathan Neuschäfer
7e1405917c powerpc/mm/32: Remove the reserved memory hack
This hack, introduced in commit c5df7f7751 ("powerpc: allow ioremap
within reserved memory regions") is now unnecessary.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:44 +11:00
Jonathan Neuschäfer
57deb8fea0 powerpc/wii: Don't rely on the reserved memory hack
Because the two memory blocks (usually called MEM1 and MEM2) are not
merged anymore, __request_region in kernel/resource.c will correctly
allow reserving regions in the physical address space between MEM1 and
MEM2, where many important peripherals are (GPIO, MMC, USB, ...).

A previous change to __ioremap_caller in arch/powerpc/mm/pgtable_32.c
ensures that multiple memblocks are properly considered in ioremap; this
makes it unnecessary to set __allow_ioremap_reserved.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:43 +11:00
Jonathan Neuschäfer
2bbf63264a powerpc/mm/32: Use page_is_ram to check for RAM
On systems where there is MMIO space between different blocks of RAM in
the physical address space, __ioremap_caller did not allow mapping these
MMIO areas, because they were below the end RAM and thus considered RAM
as well.  Use the memblock-based page_is_ram function, which returns
false for such MMIO holes.

v2:
  Keep the check for p < virt_to_phys(high_memory). On 32-bit systems
  with high memory (memory above physical address 4GiB), the high memory
  is expected to be available though ioremap. The high_memory variable
  marks the end of low memory; comparing against it means that only
  ioremap requests for low RAM will be denied.
  Reported by Michael Ellerman.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:43 +11:00
Jonathan Neuschäfer
f65e67c7e3 powerpc/mm: Use memblock API for PPC32 page_is_ram
To support accurate checking for different blocks of memory on PPC32,
use the same memblock-based approach that's already used on PPC64 also
on PPC32.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:42 +11:00
Jonathan Neuschäfer
2615c93e5f powerpc/mm: Simplify page_is_ram by using memblock_is_memory
Instead of open-coding the search in page_is_ram, call memblock_is_memory.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:42 +11:00
Jonathan Neuschäfer
041413b88d powerpc/wii.dts: Add drive slot LED
The Wii has a blue LED in the disk drive slot, which is controlled via a
GPIO line. Add this LED to wii.dts, and mark it as a panic-indicator.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:41 +11:00
Jonathan Neuschäfer
80873a0b3a powerpc/wii.dts: Add GPIO line names
These are the GPIO line names on a Nintendo Wii, as documented in:
https://wiibrew.org/wiki/Hardware/Hollywood_GPIOs

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:40 +11:00
Jonathan Neuschäfer
9693d5709f powerpc/wii.dts: Add ngpios property
The Hollywood GPIO controller supports 32 GPIOs, but on the Wii, only 24
are used.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:40 +11:00
Jonathan Neuschäfer
9cbaaec1cf powerpc/wii: Explicitly configure GPIO owner for poweroff pin
The Hollywood chipset's GPIO controller has two sets of registers: One
for access by the PowerPC CPU, and one for access by the ARM coprocessor
(but both are accessible from the PPC because the memory firewall
(AHBPROT) is usually disabled when booting Linux, today).

The wii_power_off function currently assumes that the poweroff GPIO pin
is configured for use via the ARM side, but the upcoming GPIO driver
configures all pins for use via the PPC side, breaking poweroff.

Configure the owner register explicitly in wii_power_off to make
wii_power_off work with and without the new GPIO driver.

I think the Wii can be switched to the generic gpio-poweroff driver,
after the GPIO driver is merged.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:39 +11:00
Jonathan Neuschäfer
7ab96c0a08 powerpc/wii: Probe the whole devicetree
Previously, wii_device_probe would only initialize devices under the
/hollywood node. After this patch, platform devices placed outside of
/hollywood will also be initialized.

The intended usecase for this are devices located outside of the
Hollywood chip, such as GPIO LEDs and GPIO buttons.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:39 +11:00
Michael Ellerman
1d0afc0d5a powerpc/64e: Fix oops due to deferral of paca allocation
On 64-bit Book3E systems, in setup_tlb_core_data() we reference other
CPUs pacas. But in commit 59f577743d ("powerpc/64: Defer paca
allocation until memory topology is discovered") the allocation of
non-boot-CPU pacas was deferred until later in boot.

This leads to an oops:

  CPU maps initialized for 1 thread per core
  Unable to handle kernel paging request for data at address 0x8888888888888918
  Faulting instruction address: 0xc000000000e2f0d0
  Oops: Kernel access of bad area, sig: 11 [#1]
  NIP .setup_tlb_core_data+0xdc/0x160
  Call Trace:
    .setup_tlb_core_data+0x5c/0x160 (unreliable)
    .setup_arch+0x80/0x348
    .start_kernel+0x7c/0x598
    start_here_common+0x1c/0x40

Luckily setup_tlb_core_data() is called immediately prior to
smp_setup_pacas(). So simply switching their order is sufficient to
fix the oops and seems unlikely to have any other unwanted side
effects.

Fixes: 59f577743d ("powerpc/64: Defer paca allocation until memory topology is discovered")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:38 +11:00