Commit Graph

797132 Commits

Author SHA1 Message Date
Ravi Bangoria
0c9108b083 Powerpc/perf: Wire up PMI throttling
Commit 14c63f17b1 ("perf: Drop sample rate when sampling is too
slow") introduced a way to throttle PMU interrupts if we're spending
too much time just processing those. Wire up powerpc PMI handler to
use this infrastructure.

We have throttling of the *rate* of interrupts, but this adds
throttling based on the *time taken* to process the interrupts.

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-21 11:32:49 +11:00
Alexey Kardashevskiy
c20577014f powerpc/powernv/eeh/npu: Fix uninitialized variables in opal_pci_eeh_freeze_status
The current implementation of the OPAL_PCI_EEH_FREEZE_STATUS call in
skiboot's NPU driver does not touch the pci_error_type parameter so
it might have garbage but the powernv code analyzes it nevertheless.

This initializes pcierr and fstate to zero in all call sites.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:59:03 +11:00
Alexey Kardashevskiy
a25de7af34 powerpc/powernv/ioda: Reduce a number of hooks in pnv_phb
fixup_phb() is never used, this removes it.

pick_m64_pe() and reserve_m64_pe() are always defined for all powernv
PHBs: they are initialized by pnv_ioda_parse_m64_window() which is
called unconditionally from pnv_pci_init_ioda_phb() which initializes
all known PHB types on powernv so we can open code them.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:59:03 +11:00
Alexey Kardashevskiy
f21b0a45e4 powerpc/powernv/ioda1: Remove dead code for a single device PE
At the moment PNV_IODA_PE_DEV is only used for NPU PEs which are not
present on IODA1 machines (i.e. POWER7) so let's remove a piece of
dead code.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:59:03 +11:00
Alexey Kardashevskiy
517ad4ae8a vfio/spapr_tce: Get rid of possible infinite loop
As a part of cleanup, the SPAPR TCE IOMMU subdriver releases preregistered
memory. If there is a bug in memory release, the loop in
tce_iommu_release() becomes infinite; this actually happened to me.

This makes the loop finite and prints a warning on every failure to make
the code more bug prone.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:59:03 +11:00
Alexey Kardashevskiy
fa1ada7889 powerpc/powernv/npu: Remove unused headers and a macro.
The macro and few headers are not used so remove them.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:59:03 +11:00
Alexey Kardashevskiy
bdbf649efe powerpc/powernv/ioda: Allocate indirect TCE levels of cached userspace addresses on demand
The powernv platform maintains 2 TCE tables for VFIO - a hardware TCE
table and a table with userspace addresses; the latter is used for
marking pages dirty when corresponging TCEs are unmapped from
the hardware table.

a68bd1267b ("powerpc/powernv/ioda: Allocate indirect TCE levels
on demand") enabled on-demand allocation of the hardware table,
however it missed the other table so it has still been fully allocated
at the boot time. This fixes the issue by allocating a single level,
just like we do for the hardware table.

Fixes: a68bd1267b ("powerpc/powernv/ioda: Allocate indirect TCE levels on demand")
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:59:03 +11:00
YueHaibing
8c6c942d33 powerpc/eeh: Fix debugfs_simple_attr.cocci warnings
Use DEFINE_DEBUGFS_ATTRIBUTE rather than DEFINE_SIMPLE_ATTRIBUTE
for debugfs files.

Semantic patch information:
Rationale: DEFINE_SIMPLE_ATTRIBUTE + debugfs_create_file()
imposes some significant overhead as compared to
DEFINE_DEBUGFS_ATTRIBUTE + debugfs_create_file_unsafe().

Generated by: scripts/coccinelle/api/debugfs/debugfs_simple_attr.cocci

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:59:03 +11:00
Diana Craciun
e59f5bd759 powerpc/fsl: Add FSL_PPC_BOOK3E as supported arch for nospectre_v2 boot arg
Signed-off-by: Diana Craciun <diana.craciun@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:59:03 +11:00
Diana Craciun
dfa88658fb powerpc/fsl: Update Spectre v2 reporting
Report branch predictor state flush as a mitigation for
Spectre variant 2.

Signed-off-by: Diana Craciun <diana.craciun@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:59:03 +11:00
Diana Craciun
3bc8ea8603 powerpc/fsl: Enable runtime patching if nospectre_v2 boot arg is used
If the user choses not to use the mitigations, replace
the code sequence with nops.

Signed-off-by: Diana Craciun <diana.craciun@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:59:03 +11:00
Diana Craciun
e7aa61f47b powerpc/fsl: Flush branch predictor when entering KVM
Switching from the guest to host is another place
where the speculative accesses can be exploited.
Flush the branch predictor when entering KVM.

Signed-off-by: Diana Craciun <diana.craciun@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:59:03 +11:00
Diana Craciun
7fef436295 powerpc/fsl: Flush the branch predictor at each kernel entry (32 bit)
In order to protect against speculation attacks on
indirect branches, the branch predictor is flushed at
kernel entry to protect for the following situations:
- userspace process attacking another userspace process
- userspace process attacking the kernel
Basically when the privillege level change (i.e.the kernel
is entered), the branch predictor state is flushed.

Signed-off-by: Diana Craciun <diana.craciun@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:59:03 +11:00
Diana Craciun
10c5e83afd powerpc/fsl: Flush the branch predictor at each kernel entry (64bit)
In order to protect against speculation attacks on
indirect branches, the branch predictor is flushed at
kernel entry to protect for the following situations:
- userspace process attacking another userspace process
- userspace process attacking the kernel
Basically when the privillege level change (i.e. the
kernel is entered), the branch predictor state is flushed.

Signed-off-by: Diana Craciun <diana.craciun@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:59:03 +11:00
Diana Craciun
f633a8ad63 powerpc/fsl: Add nospectre_v2 command line argument
When the command line argument is present, the Spectre variant 2
mitigations are disabled.

Signed-off-by: Diana Craciun <diana.craciun@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:59:03 +11:00
Diana Craciun
98518c4d87 powerpc/fsl: Emulate SPRN_BUCSR register
In order to flush the branch predictor the guest kernel performs
writes to the BUCSR register which is hypervisor privilleged. However,
the branch predictor is flushed at each KVM entry, so the branch
predictor has been already flushed, so just return as soon as possible
to guest.

Signed-off-by: Diana Craciun <diana.craciun@nxp.com>
[mpe: Tweak comment formatting]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:59:03 +11:00
Diana Craciun
7d8bad99ba powerpc/fsl: Fix spectre_v2 mitigations reporting
Currently for CONFIG_PPC_FSL_BOOK3E the spectre_v2 file is incorrect:

  $ cat /sys/devices/system/cpu/vulnerabilities/spectre_v2
  "Mitigation: Software count cache flush"

Which is wrong. Fix it to report vulnerable for now.

Fixes: ee13cb249f ("powerpc/64s: Add support for software count cache flush")
Cc: stable@vger.kernel.org # v4.19+
Signed-off-by: Diana Craciun <diana.craciun@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:59:03 +11:00
Diana Craciun
1cbf8990d7 powerpc/fsl: Add macro to flush the branch predictor
The BUCSR register can be used to invalidate the entries in the
branch prediction mechanisms.

Signed-off-by: Diana Craciun <diana.craciun@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:58:57 +11:00
Diana Craciun
76a5eaa38b powerpc/fsl: Add infrastructure to fixup branch predictor flush
In order to protect against speculation attacks (Spectre
variant 2) on NXP PowerPC platforms, the branch predictor
should be flushed when the privillege level is changed.
This patch is adding the infrastructure to fixup at runtime
the code sections that are performing the branch predictor flush
depending on a boot arg parameter which is added later in a
separate patch.

Signed-off-by: Diana Craciun <diana.craciun@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:53:39 +11:00
Christophe Leroy
f242e0ac95 powerpc/prom: move the device tree if not in declared memory.
If the device tree doesn't reside in the memory which is declared
inside it, it has to be moved as well as this memory will not be
mapped by the kernel.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Michael Ellerman
ec2adcd8dd powerpc: Add some documentation of ISA versions
Add some documentation on which CPU versions map to which ISA
versions. This is all publicly available information, some of it
already in the kernel source, but it's much nicer to have it all in
one place.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Michael Ellerman
2b874a5c7b powerpc/configs: Don't enable PPC_EARLY_DEBUG in defconfigs
This reverts the remains of commit b9ef7d6b11 ("powerpc: Update
default configurations").

That commit was proceeded by a commit which added a config option to
control use of BOOTX for early debug, ie. PPC_EARLY_DEBUG_BOOTX, and
then the update of the defconfigs was intended to not change behaviour
by then enabling the new config option.

However enabling PPC_EARLY_DEBUG had other consequences, notably
causing us to register the udbg console at the end of udbg_early_init().

This means on a system which doesn't have anything that BOOTX can
use (most systems), we register the udbg console very early but the
bootx code just throws everything away, meaning early boot messages
are never printed to the console.

What we want to happen is for the udbg console to only be registered
later (from setup_arch()) once we've setup udbg_putc, and then all
early boot messages will be replayed.

Fixes: b9ef7d6b11 ("powerpc: Update default configurations")
Reported-by: Torsten Duwe <duwe@lst.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Arnd Bergmann
2fea82db11 powerpc: eeh_event: convert semaphore to completion
For this use case, completions and semaphores are equivalent,
but semaphores are an awkward interface that should generally
be avoided, so use the completion instead.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Greg Kurz
d1f75a9684 ocxl/afu_irq: Don't include <asm/pnv-ocxl.h>
The AFU irq code doesn't need to reach out to the platform.

Signed-off-by: Greg Kurz <groug@kaod.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Greg Kurz
759bc01586 ocxl: Clarify error path in setup_xsl_irq()
Implementing rollback with goto and labels is a common practice that
leads to prettier and more maintainable code. FWIW, this design pattern
is already being used in alloc_link() a few lines below in this file.

Do the same in setup_xsl_irq().

Signed-off-by: Greg Kurz <groug@kaod.org>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Benjamin Herrenschmidt
3cfb9ebe90 powerpc/44x/bamboo: Fix PCI range
The bamboo dts has a bug: it uses a non-naturally aligned range
for PCI memory space. This isnt' supported by the code, thus
causing PCI to break on this system.

This is due to the fact that while the chip memory map has 1G
reserved for PCI memory, it's only 512M aligned. The code doesn't
know how to split that into 2 different PMMs and fails, so limit
the region to 512M.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Darren Stevens
51f4cc2047 powerpc/pasemi: Add Nemo board IRQ initroutine
Add a IRQ init routine for the Nemo board which inits and attatches
the i8259 found in the SB600, and a cascade routine to dispatch the
interrupts.

Signed-off-by: Darren Stevens <darren@stevens-zone.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Darren Stevens
656fdf3ad8 powerpc/pasemi: Add Nemo board device init code.
Add routines for Nemo specific devices to init at boot time, these
being board level power-off and SB600's rtc.

Also add a run time variable to prevent these being activated
if we boot on a reference board.

Signed-off-by: Darren Stevens <darren@stevens-zone.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Darren Stevens
0428a5f494 powerpc/pasemi: Add Nemo board IRQ initroutine
Add a IRQ init routine for the Nemo board which inits and attatches
the i8259 found in the SB600, and a cascade routine to dispatch the
interrupts.

Signed-off-by: Darren Stevens <darren@stevens-zone.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Darren Stevens
68f211a4d1 powerpc/pasemi: Add PCI initialisation for Nemo board.
The A-Eon Amigaone X1000's Nemo motherboard has an AMD SB600
connected to one of the PCI-e root ports on its PaSemi
Pwrficient 1628M SoC. Normally the SB600 southbridge would be
connected to a hidden PCI-e port on the system's northbridge,
and as a result doesn't fully comply with the PCI-e spec.

Add code to relax the PCI-e detection in both the root port
and the Linux kernel allowing on board devices to be detected.

Signed-off-by: Darren Stevens <darren@stevens-zone.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Christophe Leroy
49a502ea23 powerpc/mm: Make NULL pointer deferences explicit on bad page faults.
As several other arches including x86, this patch makes it explicit
that a bad page fault is a NULL pointer dereference when the fault
address is lower than PAGE_SIZE

In the mean time, this page makes all bad_page_fault() messages
shorter so that they remain on one single line. And it prefixes them
by "BUG: " so that they get easily grepped.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Avoid pr_cont()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
8dbdec0bcb powerpc/ptrace: Combine SYSCALL_EMU & SYSCALL_TRACE handling
Combine the SYSCALL_EMU and SYSCALL_TRACE handling so that we only
call tracehook_report_syscall_entry() in one place.

Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
[mpe: Flesh out change log, s/cached_flags/flags/, reflow comments]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Christoph Hellwig
25078dc1f7 powerpc: use mm zones more sensibly
Powerpc has somewhat odd usage where ZONE_DMA is used for all memory on
common 64-bit configfs, and ZONE_DMA32 is used for 31-bit schemes.

Move to a scheme closer to what other architectures use (and I dare to
say the intent of the system):

 - ZONE_DMA: optionally for memory < 31-bit (64-bit embedded only)
 - ZONE_NORMAL: everything addressable by the kernel
 - ZONE_HIGHMEM: memory > 32-bit for 32-bit kernels

Also provide information on how ZONE_DMA is used by defining
ARCH_ZONE_DMA_BITS.

Contains various fixes from Benjamin Herrenschmidt.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Christoph Hellwig
f3e5a8579c cxl: drop the dma_set_mask callback from vphb
The CXL code never even looks at the dma mask, so there is no good
reason for this sanity check.  Remove it because it gets in the way
of the dma ops refactoring.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Christoph Hellwig
44a0337b32 powerpc/dma: split the two __dma_alloc_coherent implementations
The implemementation for the CONFIG_NOT_COHERENT_CACHE case doesn't share
any code with the one for systems with coherent caches.  Split it off
and merge it with the helpers in dma-noncoherent.c that have no other
callers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Christoph Hellwig
9c15a87cfc powerpc/dma: remove the unused dma_iommu_ops export
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Christoph Hellwig
acddff9dc4 powerpc/dma: remove the unused ISA_DMA_THRESHOLD export
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Christoph Hellwig
0e652390fb powerpc/dma: remove the unused ARCH_HAS_DMA_MMAP_COHERENT define
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Christoph Hellwig
67d8208fba crypto4xx_core: don't abuse __dma_sync_page
This function is internal to the DMA API implementation. Instead use
the DMA API to properly unmap. Note that the DMA API usage in this
driver is a disaster and urgently needs some work - it is missing all
the unmaps, seems to do a secondary map where it looks like it should
to a unmap in one place to work around cache coherency and the
directions passed in seem to be partially wrong.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Christian Lamparter <chunkeey@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Christoph Hellwig
0aeba2d0d2 powerpc/dma: properly wire up the unmap_page and unmap_sg methods
The unmap methods need to transfer memory ownership back from the
device to the cpu by identical means as dma_sync_*_to_cpu. I'm not
sure powerpc needs to do any work in this transfer direction, but
given that it does invalidate the caches in dma_sync_*_to_cpu already
we should make sure we also do so on unmapping.

Signed-off-by: Christoph Hellwig <hch@lst.de>
[mpe: s/dir/direction in dma_nommu_unmap_page()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Christoph Hellwig
9286356907 powerpc: allow NOT_COHERENT_CACHE for amigaone
AMIGAONE selects NOT_COHERENT_CACHE, so we better allow it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Christophe Leroy
b18f0ae92b powerpc/prom: fix early DEBUG messages
This patch fixes early DEBUG messages in prom.c:
- Use %px instead of %p to see the addresses
- Cast memblock_phys_mem_size() with (unsigned long long) to
avoid build failure when phys_addr_t is not 64 bits.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Greg Kurz
e1e71e2017 ocxl: Fix endiannes bug in ocxl_link_update_pe()
All fields in the PE are big-endian. Use cpu_to_be32() like everywhere
else something is written to the PE. Otherwise a wrong TID will be used
by the NPU. If this TID happens to point to an existing thread sharing
the same mm, it could be woken up by error. This is highly improbable
though. The likely outcome of this is the NPU not finding the target
thread and forcing the AFU into sending an interrupt, which userspace
is supposed to handle anyway.

Fixes: e948e06fc6 ("ocxl: Expose the thread_id needed for wait on POWER9")
Cc: stable@vger.kernel.org      # v4.18
Signed-off-by: Greg Kurz <groug@kaod.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Joel Stanley
72e7bcc2cd powerpc/32: Avoid unsupported flags with clang
When building for ppc32 with clang these flags are unsupported:

  -ffixed-r2 and -mmultiple

llvm's lib/Target/PowerPC/PPCRegisterInfo.cpp marks r2 as reserved on
when building for SVR4ABI and !ppc64:

  // The SVR4 ABI reserves r2 and r13
  if (Subtarget.isSVR4ABI()) {
    // We only reserve r2 if we need to use the TOC pointer. If we have no
    // explicit uses of the TOC pointer (meaning we're a leaf function with
    // no constant-pool loads, etc.) and we have no potential uses inside an
    // inline asm block, then we can treat r2 has an ordinary callee-saved
    // register.
    const PPCFunctionInfo *FuncInfo = MF.getInfo<PPCFunctionInfo>();
    if (!TM.isPPC64() || FuncInfo->usesTOCBasePtr() || MF.hasInlineAsm())
      markSuperRegs(Reserved, PPC::R2);  // System-reserved register
    markSuperRegs(Reserved, PPC::R13); // Small Data Area pointer register
  }

This means we can safely omit -ffixed-r2 when building for 32-bit
targets.

The -mmultiple/-mno-multiple flags are not supported by clang, so
platforms that might support multiple miss out on using multiple word
instructions.

We wrap these flags in cc-option so that when Clang gains support the
kernel will be able use these flags.

Clang 8 can then build a ppc44x_defconfig which boots in Qemu:

  make CC=clang-8 ARCH=powerpc CROSS_COMPILE=powerpc-linux-gnu-  ppc44x_defconfig
  ./scripts/config -e CONFIG_DEVTMPFS -d DEVTMPFS_MOUNT
  make CC=clang-8 ARCH=powerpc CROSS_COMPILE=powerpc-linux-gnu-

  qemu-system-ppc -M bamboo \
   -kernel arch/powerpc/boot/zImage \
   -dtb arch/powerpc/boot/dts/bamboo.dtb \
   -initrd ~/ppc32-440-rootfs.cpio \
   -nographic -serial stdio -monitor pty -append "console=ttyS0"

Link: https://github.com/ClangBuiltLinux/linux/issues/261
Link: https://bugs.llvm.org/show_bug.cgi?id=39556
Link: https://bugs.llvm.org/show_bug.cgi?id=39555
Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 20:53:11 +11:00
Joel Stanley
e213574a44 raid6/ppc: Fix build for clang
We cannot build these files with clang as it does not allow altivec
instructions in assembly when -msoft-float is passed.

Jinsong Ji <jji@us.ibm.com> wrote:
> We currently disable Altivec/VSX support when enabling soft-float.  So
> any usage of vector builtins will break.
>
> Enable Altivec/VSX with soft-float may need quite some clean up work, so
> I guess this is currently a limitation.
>
> Removing -msoft-float will make it work (and we are lucky that no
> floating point instructions will be generated as well).

This is a workaround until the issue is resolved in clang.

Link: https://bugs.llvm.org/show_bug.cgi?id=31177
Link: https://github.com/ClangBuiltLinux/linux/issues/239
Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 20:53:11 +11:00
Madhavan Srinivasan
3757cba80a powerpc/perf: Remove l2 bus events from HW cache event array
Remove PM_L2_ST_MISS and PM_L2_ST from HW cache event array since
these are bus events. And these needs to be programmed in groups.
Hence remove them.

Fixes: f1fb60bfde ('powerpc/perf: Export Power9 generic and cache events to sysfs')
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 20:53:11 +11:00
Madhavan Srinivasan
59029136d7 powerpc/perf: Add constraints for power9 l2/l3 bus events
In previous generation processors, both bus events and direct
events of performance monitoring unit can be individually
programmabled and monitored in PMCs.

But in Power9, L2/L3 bus events are always available as a
"bank" of 4 events. To obtain the counts for any of the
l2/l3 bus events in a given bank, the user will have to
program PMC4 with corresponding l2/l3 bus event for that
bank.

Patch enforce two contraints incase of L2/L3 bus events.

1)Any L2/L3 event when programmed is also expected to program corresponding
PMC4 event from that group.
2)PMC4 event should always been programmed first due to group constraint
logic limitation

For ex. consider these L3 bus events

PM_L3_PF_ON_CHIP_MEM (0x460A0),
PM_L3_PF_MISS_L3 (0x160A0),
PM_L3_CO_MEM (0x260A0),
PM_L3_PF_ON_CHIP_CACHE (0x360A0),

1) This is an INVALID group for L3 Bus event monitoring,
since it is missing PMC4 event.
	perf stat -e "{r160A0,r260A0,r360A0}" < >

And this is a VALID group for L3 Bus events:
	perf stat -e "{r460A0,r160A0,r260A0,r360A0}" < >

2) This is an INVALID group for L3 Bus event monitoring,
since it is missing PMC4 event.
	perf stat -e "{r260A0,r360A0}" < >

And this is a VALID group for L3 Bus events:
	perf stat -e "{r460A0,r260A0,r360A0}" < >

3) This is an INVALID group for L3 Bus event monitoring,
since it is missing PMC4 event.
	perf stat -e "{r360A0}" < >

And this is a VALID group for L3 Bus events:
	perf stat -e "{r460A0,r360A0}" < >

Patch here implements group constraint logic suggested by Michael Ellerman.

Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 20:53:11 +11:00
Madhavan Srinivasan
2d46d4877b powerpc/perf: Fix unit_sel/cache_sel checks
Raw event code has couple of fields "unit" and "cache" in it, to capture
the "unit" to monitor for a given pmcxsel and cache reload qualifier to
program in MMCR1.

isa207_get_constraint() refers "unit" field to update the MMCRC (L2/L3)
Event bus control fields with "cache" bits of the raw event code.
These are power8 specific and not supported by PowerISA v3.0 pmu. So wrap
the checks to be power8 specific. Also, "cache" bit field is referred to
update MMCR1[16:17] and this check can be power8 specific.

Fixes: 7ffd948fae ('powerpc/perf: factor out power8 pmu functions')
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 20:53:11 +11:00
Madhavan Srinivasan
8c31459d61 powerpc/perf: Cleanup cache_sel bits comment
Update the raw event code comment in power9-pmu.c with respect to
"cache" bits, since power9 MMCRC does not support these.

Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 20:53:11 +11:00
Madhavan Srinivasan
333804dc3b powerpc/perf: Update perf_regs structure to include SIER
On each sample, Sample Instruction Event Register (SIER) content
is saved in pt_regs. SIER does not have a entry as-is in the pt_regs
but instead, SIER content is saved in the "dar" register of pt_regs.

Patch adds another entry to the perf_regs structure to include the "SIER"
printing which internally maps to the "dar" of pt_regs.

It also check for the SIER availability in the platform and present
value accordingly

Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 20:53:11 +11:00