Commit Graph

706667 Commits

Author SHA1 Message Date
James Morse
8d66772e86 arm64: Mask all exceptions during kernel_exit
To take RAS Exceptions as quickly as possible we need to keep SError
unmasked as much as possible. We need to mask it during kernel_exit
as taking an error from this code will overwrite the exception-registers.

Adding a naked 'disable_daif' to kernel_exit causes a performance problem
for micro-benchmarks that do no real work, (e.g. calling getpid() in a
loop). This is because the ret_to_user loop has already masked IRQs so
that the TIF_WORK_MASK thread flags can't change underneath it, adding
disable_daif is an additional self-synchronising operation.

In the future, the RAS APEI code may need to modify the TIF_WORK_MASK
flags from an SError, in which case the ret_to_user loop must mask SError
while it examines the flags.

Disable all exceptions for return to EL1. For return to EL0 get the
ret_to_user loop to leave all exceptions masked once it has done its
work, this avoids an extra pstate-write.

Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Julien Thierry <julien.thierry@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-11-02 15:55:41 +00:00
James Morse
41bd5b5d22 arm64: Move the async/fiq helpers to explicitly set process context flags
Remove the local_{async,fiq}_{en,dis}able macros as they don't respect
our newly defined order and are only used to set the flags for process
context when we bring CPUs online.

Add a helper to do this. The IRQ flag varies as we want it masked on
the boot CPU until we are ready to handle interrupts.
The boot CPU unmasks SError during early boot once it can print an error
message. If we can print an error message about SError, we can do the
same for FIQ. Debug exceptions are already enabled by __cpu_setup(),
which has also configured MDSCR_EL1 to disable MDE and KDE.

Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Julien Thierry <julien.thierry@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-11-02 15:55:41 +00:00
James Morse
65be7a1b79 arm64: introduce an order for exceptions
Currently SError is always masked in the kernel. To support RAS exceptions
using SError on hardware with the v8.2 RAS Extensions we need to unmask
SError as much as possible.

Let's define an order for masking and unmasking exceptions. 'dai' is
memorable and effectively what we have today.

Disabling debug exceptions should cause all other exceptions to be masked.
Masking SError should mask irq, but not disable debug exceptions.
Masking irqs has no side effects for other flags. Keeping to this order
makes it easier for entry.S to know which exceptions should be unmasked.

FIQ is never expected, but we mask it when we mask debug exceptions, and
unmask it at all other times.

Given masking debug exceptions masks everything, we don't need macros
to save/restore that bit independently. Remove them and switch the last
caller over to use the daif calls.

Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Julien Thierry <julien.thierry@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-11-02 15:55:41 +00:00
James Morse
0fbeb31875 arm64: explicitly mask all exceptions
There are a few places where we want to mask all exceptions. Today we
do this in a piecemeal fashion, typically we expect the caller to
have masked irqs and the arch code masks debug exceptions, ignoring
serror which is probably masked.

Make it clear that 'mask all exceptions' is the intention by adding
helpers to do exactly that.

This will let us unmask SError without having to add 'oh and SError'
to these paths.

Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Julien Thierry <julien.thierry@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-11-02 15:55:40 +00:00
Yisheng Xie
c10f0d06ad arm64: suspend: remove useless included file
After commit 9e8e865bbe ("arm64: unify idmap removal"), we no need to
flush tlb in suspend.c, so the included file tlbflush.h can be removed.

Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-11-02 14:37:01 +00:00
Will Deacon
80b6eb04b5 arm64: Don't walk page table for user faults in do_mem_abort
Commit 42dbf54e88 ("arm64: consistently log ESR and page table")
dumps page table entries for user faults hitting do_bad entries in the
fault handler table. Whilst this shouldn't really happen in practice,
it's not beyond the realms of possibility if e.g. running an old kernel
on a new CPU.

Generally, we want to avoid exposing physical addresses under the control
of userspace (see commit bf396c09c2 ("arm64: mm: don't print out page
table entries on EL0 faults")), so walk the page tables only on exceptions
from EL1.

Reported-by: Kristina Martsenko <kristina.martsenko@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-11-02 13:52:48 +00:00
Mark Rutland
c80ed088a5 arm64: vdso: fix clock_getres for 4GiB-aligned res
The vdso tries to check for a NULL res pointer in __kernel_clock_getres,
but only checks the lower 32 bits as is uses CBZ on the W register the
res pointer is held in.

Thus, if the res pointer happened to be aligned to a 4GiB boundary, we'd
spuriously skip storing the timespec to it, while returning a zero error code
to the caller.

Prevent this by checking the whole pointer, using CBZ on the X register
the res pointer is held in.

Fixes: 9031fefde6 ("arm64: VDSO support")
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reported-by: Andrew Pinski <apinski@cavium.com>
Reported-by: Mark Salyzyn <salyzyn@android.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-31 09:49:33 +00:00
Nick Desaulniers
fd9dde6abc arm64: prevent regressions in compressed kernel image size when upgrading to binutils 2.27
Upon upgrading to binutils 2.27, we found that our lz4 and gzip
compressed kernel images were significantly larger, resulting is 10ms
boot time regressions.

As noted by Rahul:
"aarch64 binaries uses RELA relocations, where each relocation entry
includes an addend value. This is similar to x86_64.  On x86_64, the
addend values are also stored at the relocation offset for relative
relocations. This is an optimization: in the case where code does not
need to be relocated, the loader can simply skip processing relative
relocations.  In binutils-2.25, both bfd and gold linkers did this for
x86_64, but only the gold linker did this for aarch64.  The kernel build
here is using the bfd linker, which stored zeroes at the relocation
offsets for relative relocations.  Since a set of zeroes compresses
better than a set of non-zero addend values, this behavior was resulting
in much better lz4 compression.

The bfd linker in binutils-2.27 is now storing the actual addend values
at the relocation offsets. The behavior is now consistent with what it
does for x86_64 and what gold linker does for both architectures.  The
change happened in this upstream commit:
https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=1f56df9d0d5ad89806c24e71f296576d82344613
Since a bunch of zeroes got replaced by non-zero addend values, we see
the side effect of lz4 compressed image being a bit bigger.

To get the old behavior from the bfd linker, "--no-apply-dynamic-relocs"
flag can be used:
$ LDFLAGS="--no-apply-dynamic-relocs" make
With this flag, the compressed image size is back to what it was with
binutils-2.25.

If the kernel is using ASLR, there aren't additional runtime costs to
--no-apply-dynamic-relocs, as the relocations will need to be applied
again anyway after the kernel is relocated to a random address.

If the kernel is not using ASLR, then presumably the current default
behavior of the linker is better. Since the static linker performed the
dynamic relocs, and the kernel is not moved to a different address at
load time, it can skip applying the relocations all over again."

Some measurements:

$ ld -v
GNU ld (binutils-2.25-f3d35cf6) 2.25.51.20141117
                    ^
$ ls -l vmlinux
-rwxr-x--- 1 ndesaulniers eng 300652760 Oct 26 11:57 vmlinux
$ ls -l Image.lz4-dtb
-rw-r----- 1 ndesaulniers eng 16932627 Oct 26 11:57 Image.lz4-dtb

$ ld -v
GNU ld (binutils-2.27-53dd00a1) 2.27.0.20170315
                    ^
pre patch:
$ ls -l vmlinux
-rwxr-x--- 1 ndesaulniers eng 300376208 Oct 26 11:43 vmlinux
$ ls -l Image.lz4-dtb
-rw-r----- 1 ndesaulniers eng 18159474 Oct 26 11:43 Image.lz4-dtb

post patch:
$ ls -l vmlinux
-rwxr-x--- 1 ndesaulniers eng 300376208 Oct 26 12:06 vmlinux
$ ls -l Image.lz4-dtb
-rw-r----- 1 ndesaulniers eng 16932466 Oct 26 12:06 Image.lz4-dtb

By Siqi's measurement w/ gzip:
binutils 2.27 with this patch (with --no-apply-dynamic-relocs):
Image 41535488
Image.gz 13404067

binutils 2.27 without this patch (without --no-apply-dynamic-relocs):
Image 41535488
Image.gz 14125516

Any compression scheme should be able to get better results from the
longer runs of zeros, not just GZIP and LZ4.

10ms boot time savings isn't anything to get excited about, but users of
arm64+compression+bfd-2.27 should not have to pay a penalty for no
runtime improvement.

Reported-by: Gopinath Elanchezhian <gelanchezhian@google.com>
Reported-by: Sindhuri Pentyala <spentyala@google.com>
Reported-by: Wei Wang <wvw@google.com>
Suggested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Suggested-by: Rahul Chaudhry <rahulchaudhry@google.com>
Suggested-by: Siqi Lin <siqilin@google.com>
Suggested-by: Stephen Hines <srhines@google.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
[will: added comment to Makefile]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-30 13:45:12 +00:00
Catalin Marinas
6218f96c58 arm64: Implement arch-specific pte_access_permitted()
The generic pte_access_permitted() implementation only checks for
pte_present() (together with the write permission where applicable).
However, for both kernel ptes and PROT_NONE mappings pte_present() also
returns true on arm64 even though such mappings are not user accessible.
Additionally, arm64 now supports execute-only user permission
(PROT_EXEC) which is implemented by clearing the PTE_USER bit.

With this patch the arm64 implementation of pte_access_permitted()
checks for the PTE_VALID and PTE_USER bits together with writable access
if applicable.

Cc: <stable@vger.kernel.org>
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-30 12:41:15 +00:00
Will Deacon
d7b1d22d38 arm64: uapi: Remove PSR_Q_BIT
PSTATE.Q only exists for AArch32, which can be referred to using
COMPAT_PSR_Q_BIT. Remove PSR_Q_BIT, since the native bit doesn't exist
in the architecture

Tested-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-27 16:27:03 +01:00
Will Deacon
b7300d4c03 arm64: traps: Pretty-print pstate in register dumps
We can decode the PSTATE easily enough, so pretty-print it in register
dumps.

Tested-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-27 16:26:58 +01:00
Will Deacon
a25ffd3a63 arm64: traps: Don't print stack or raw PC/LR values in backtraces
Printing raw pointer values in backtraces has potential security
implications and are of questionable value anyway.

This patch follows x86's lead and removes the "Exception stack:" dump
from kernel backtraces, as well as converting PC/LR values to symbols
such as "sysrq_handle_crash+0x20/0x30".

Tested-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-27 16:26:53 +01:00
Mark Rutland
42dbf54e88 arm64: consistently log ESR and page table
When we take a fault we can't handle, we try to dump some relevant
information, but we're not consistent about doing so.

In do_mem_abort(), we log the full ESR, but don't dump a page table
walk. In __do_kernel_fault, we dump an attempted decoding of the ESR
(but not the ESR itself) along with a page table walk.

Let's try to make things more consistent by dumping the full ESR in
mem_abort_decode(), and having do_mem_abort dump a page table walk. The
existing dump of the ESR in do_mem_abort() is rendered redundant, and
removed.

Tested-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Julien Thierry <julien.thierry@arm.com>
Cc: Kristina Martsenko <kristina.martsenko@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-27 16:26:47 +01:00
Dave Martin
fa3eb71d96 arm64: asm-bug: Renumber macro local labels to avoid clashes
Currently ASM_BUG() and its constituent macros define local
assembler labels 0, 1 and 2 internally, which carries a high risk
of clash with callers' labels and consequent mis-assembly.

This patch gives the labels a big random offset to minimise the
chance of such errors.

Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-25 15:57:15 +01:00
Julien Thierry
6436beeee5 arm64: Fix single stepping in kernel traps
Software Step exception is missing after stepping a trapped instruction.

Ensure SPSR.SS gets set to 0 after emulating/skipping a trapped instruction
before doing ERET.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
[will: replaced AARCH32_INSN_SIZE with 4]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-25 11:57:33 +01:00
Julien Thierry
e28cc02559 arm64: Use existing defines for mdscr
Literal values are being used to set single stepping in mdscr from assembly
code. There are already existing defines representing those values, use
those instead of the literal values.

Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-25 11:56:59 +01:00
Mark Salyzyn
9ca255bf04 arm64: Avoid aligning normal memory pointers in __memcpy_{to,from}io
__memcpy_{to,from}io fall back to byte-at-a-time copying if both the
source and destination pointers are not 8-byte aligned. Since one of the
pointers always points at normal memory, this is unnecessary and
detrimental to performance, so only do byte copying until we hit an 8-byte
boundary for the device pointer.

This change was motivated by performance issues in the pstore driver.
On a test platform, measuring probe time for pstore, console buffer
size of 1/4MB and pmsg of 1/2MB, was in the 90-107ms region. Change
managed to reduce it to 10-25ms, an improvement in boot time.

Cc: Kees Cook <keescook@chromium.org>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Mark Salyzyn <salyzyn@android.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-24 16:23:07 +01:00
Will Deacon
1e0c661f05 Merge branch 'for-next/perf' into aarch64/for-next/core
Merge in ARM PMU and perf updates for 4.15:

  - Support for the Statistical Profiling Extension
  - Support for Hisilicon's SoC PMU

Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-24 16:06:56 +01:00
Julien Thierry
611479c79a arm/arm64: pmu: Distinguish percpu irq and percpu_devid irq
arm_pmu interrupts are maked as PERCPU even when these are not local
physical interrupts to a single CPU. When using non-local interrupts,
interrupts marked as PERCPU will not get freed not disabled properly
by the PMU driver.

Check if interrupts are local to a single CPU with PERCPU_DEVID since
this is what the PMU driver really needs to know.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-24 16:04:05 +01:00
Julien Thierry
08395c7f4d irqdesc: Add function to identify percpu_devid irqs
irq_is_percpu indicates whether an irq should only target a single cpu.
PERCPU_DEVID flag indicates that an irq can be configured differently on
each cpu it can target.

Provide a function to check whether an irq is PERCPU_DEVID.

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Julien Thierry <julien.thierry@arm.com>
2017-10-24 16:03:28 +01:00
Suzuki K Poulose
5bdecb7971 arm64: Fix the feature type for ID register fields
Now that the ARM ARM clearly specifies the rules for inferring
the values of the ID register fields, fix the types of the
feature bits we have in the kernel.

As per ARM ARM DDI0487B.b, section D10.1.4 "Principles of the
ID scheme for fields in ID registers" lists the registers to
which the scheme applies along with the exceptions.

This patch changes the relevant feature bits from FTR_EXACT
to FTR_LOWER_SAFE to select the safer value. This will enable
an older kernel running on a new CPU detect the safer option
rather than completely disabling the feature.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Martin <dave.martin@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-19 17:42:08 +01:00
Shaokun Zhang
0714134214 arm64: MAINTAINERS: hisi: Add HiSilicon SoC PMU support
Add support HiSilicon SoC uncore PMU driver.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-19 17:06:35 +01:00
Shaokun Zhang
904dcf03f0 perf: hisi: Add support for HiSilicon SoC DDRC PMU driver
This patch adds support for DDRC PMU driver in HiSilicon SoC chip, Each
DDRC has own control, counter and interrupt registers and is an separate
PMU. For each DDRC PMU, it has 8-fixed-purpose counters which have been
mapped to 8-events by hardware, it assumes that counter index is equal
to event code (0 - 7) in DDRC PMU driver. Interrupt is supported to
handle counter (32-bits) overflow.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Signed-off-by: Anurup M <anurup.m@huawei.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-19 17:06:35 +01:00
Shaokun Zhang
2bab3cf910 perf: hisi: Add support for HiSilicon SoC HHA PMU driver
L3 cache coherence is maintained by Hydra Home Agent (HHA) in HiSilicon
SoC. This patch adds support for HHA PMU driver, Each HHA has own
control, counter and interrupt registers and is an separate PMU. For
each HHA PMU, it has 16-programable counters and each counter is
free-running. Interrupt is supported to handle counter (48-bits)
overflow.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Signed-off-by: Anurup M <anurup.m@huawei.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-19 17:06:35 +01:00
Shaokun Zhang
2940bc4333 perf: hisi: Add support for HiSilicon SoC L3C PMU driver
This patch adds support for L3C PMU driver in HiSilicon SoC chip, Each
L3C has own control, counter and interrupt registers and is an separate
PMU. For each L3C PMU, it has 8-programable counters and each counter
is free-running. Interrupt is supported to handle counter (48-bits)
overflow.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Signed-off-by: Anurup M <anurup.m@huawei.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-19 17:06:34 +01:00
Shaokun Zhang
6ce4ef9419 perf: hisi: Add support for HiSilicon SoC uncore PMU driver
This patch adds support HiSilicon SoC uncore PMU driver framework and
interfaces.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Signed-off-by: Anurup M <anurup.m@huawei.com>
[will: Fix leader accounting in uncore group validation]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-19 17:06:34 +01:00
Shaokun Zhang
3125b5b2a3 Documentation: perf: hisi: Documentation for HiSilicon SoC PMU driver
This patch adds documentation for the uncore PMUs on HiSilicon SoC.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Signed-off-by: Anurup M <anurup.m@huawei.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-19 17:06:34 +01:00
Julien Thierry
3f7c86b238 arm64: Update fault_info table with new exception types
Based on: ARM Architecture Reference Manual, ARMv8 (DDI 0487B.b).

ARMv8.1 introduces the optional feature ARMv8.1-TTHM which can trigger a
new type of memory abort. This exception is triggered when hardware update
of page table flags is not atomic in regards to other memory accesses.
Replace the corresponding unknown entry with a more accurate one.

Cf: Section D10.2.28 ESR_ELx, Exception Syndrome Register (p D10-2381),
section D4.4.11 Restriction on memory types for hardware updates on page
tables (p D4-2116 - D4-2117).

ARMv8.2 does not add new exception types, however it is worth mentioning
that when obligatory feature RAS (optional for ARMv8.{0,1}) is implemented,
exceptions related to "Synchronous parity or ECC error on memory access,
not on translation table walk" become reserved and should not occur.

Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-19 10:57:40 +01:00
Will Deacon
d5d9696b03 drivers/perf: Add support for ARMv8.2 Statistical Profiling Extension
The ARMv8.2 architecture introduces the optional Statistical Profiling
Extension (SPE).

SPE can be used to profile a population of operations in the CPU pipeline
after instruction decode. These are either architected instructions (i.e.
a dynamic instruction trace) or CPU-specific uops and the choice is fixed
statically in the hardware and advertised to userspace via caps/. Sampling
is controlled using a sampling interval, similar to a regular PMU counter,
but also with an optional random perturbation to avoid falling into patterns
where you continuously profile the same instruction in a hot loop.

After each operation is decoded, the interval counter is decremented. When
it hits zero, an operation is chosen for profiling and tracked within the
pipeline until it retires. Along the way, information such as TLB lookups,
cache misses, time spent to issue etc is captured in the form of a sample.
The sample is then filtered according to certain criteria (e.g. load
latency) that can be specified in the event config (described under
format/) and, if the sample satisfies the filter, it is written out to
memory as a record, otherwise it is discarded. Only one operation can
be sampled at a time.

The in-memory buffer is linear and virtually addressed, raising an
interrupt when it fills up. The PMU driver handles these interrupts to
give the appearance of a ring buffer, as expected by the AUX code.

The in-memory trace-like format is self-describing (though not parseable
in reverse) and written as a series of records, with each record
corresponding to a sample and consisting of a sequence of packets. These
packets are defined by the architecture, although some have CPU-specific
fields for recording information specific to the microarchitecture.

As a simple example, a record generated for a branch instruction may
consist of the following packets:

  0 (Address) : Virtual PC of the branch instruction
  1 (Type)    : Conditional direct branch
  2 (Counter) : Number of cycles taken from Dispatch to Issue
  3 (Address) : Virtual branch target + condition flags
  4 (Counter) : Number of cycles taken from Dispatch to Complete
  5 (Events)  : Mispredicted as not-taken
  6 (END)     : End of record

It is also possible to toggle properties such as timestamp packets in
each record.

This patch adds support for SPE in the form of a new perf driver.

Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-18 12:53:34 +01:00
Will Deacon
4b8b77a4ec dt-bindings: Document devicetree binding for ARM SPE
This patch documents the devicetree binding in use for ARM SPE.

Cc: Rob Herring <robh@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-18 12:53:33 +01:00
Will Deacon
b0c57e1071 arm64: head: Init PMSCR_EL2.{PA,PCT} when entered at EL2 without VHE
When booting at EL2, ensure that we permit the EL1 host to sample
physical addresses and physical counter values using SPE.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-18 12:53:32 +01:00
Will Deacon
a173c390d9 arm64: sysreg: Move SPE registers and PSB into common header files
SPE is part of the v8.2 architecture, so move its system register and
field definitions into sysreg.h and the new PSB barrier into barrier.h

Finally, move KVM over to using the generic definitions so that it
doesn't have to open-code its own versions.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-18 12:53:32 +01:00
Will Deacon
085b30625e perf/core: Add PERF_AUX_FLAG_COLLISION to report colliding samples
The ARM SPE architecture permits an implementation to ignore a sample
if the sample is due to be taken whilst another sample is already being
produced. In this case, it is desirable to report the collision to
userspace, as they may want to lower the sample period.

This patch adds a PERF_AUX_FLAG_COLLISION flag, so that such events can
be relayed to userspace.

Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-18 12:53:31 +01:00
Will Deacon
bc1d202023 perf/core: Export AUX buffer helpers to modules
Perf PMU drivers using AUX buffers cannot be built as modules unless
the AUX helpers are exported.

This patch exports perf_aux_output_{begin,end,skip} and perf_get_aux to
modules.

Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-18 12:53:30 +01:00
Will Deacon
5ffeb0501c genirq: export irq_get_percpu_devid_partition to modules
Any modular driver using cluster-affine PPIs needs to be able to call
irq_get_percpu_devid_partition so that it can enable the IRQ on the
correct subset of CPUs.

This patch exports the symbol so that it can be called from within a
module.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-18 12:53:29 +01:00
Will Deacon
0515ce0ff8 ACPI IORT updates for v4.15; patches content is logically split into
the following subseries:
 
 - Code clean-ups (A.Yadav, L.Pieralisi)
 - Platform devices inizialization rework in preparation for IORT PMCG
   handling (L.Pieralisi)
 - Mapping API rework to enable MSIs for IORT components as defined in
   IORT specification issue C (H.Guo, L.Pieralisi)
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Merge tag 'acpi/iort-for-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/lpieralisi/linux into aarch64/for-next/core

Pull arm64 ACPI IORT updates from Lorenzo Pieralisi:

- Code clean-ups (A.Yadav, L.Pieralisi)
- Platform devices inizialization rework in preparation for IORT PMCG
  handling (L.Pieralisi)
- Mapping API rework to enable MSIs for IORT components as defined in
  IORT specification issue C (H.Guo, L.Pieralisi)

Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-17 12:33:13 +01:00
Lorenzo Pieralisi
65637901a3 ACPI/IORT: Enable SMMUv3/PMCG IORT MSI domain set-up
ITS specific mappings for SMMUv3/PMCG components can be retrieved
through special index mapping entries introduced in IORT revision C.

Introduce a new API iort_set_device_domain() to set the MSI domain for
SMMUv3/PMCG nodes (extendable to any future IORT node requiring special
index ITS mapping entries) that represent MSI through special index
mappings in order to enable MSI support for the devices their nodes
represent.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
2017-10-16 14:30:15 +01:00
Hanjun Guo
86456a3f19 ACPI/IORT: Add SMMUv3 specific special index mapping handling
IORT revision C introduced a mapping entry binding to describe ITS
device ID mapping for SMMUv3 MSI interrupts.

Enable the single mapping flag (ie that is used by SMMUv3 component for
its special index mappings) for the SMMUv3 node in the IORT mapping API
and add IORT code to handle special index mapping entry for the SMMUv3
IORT nodes to enable their MSI interrupts. In case the ACPICA for
SMMUv3 device ID mapping is not ready, use the ACPICA version as a guard
for function iort_get_id_mapping_index().

Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
[lorenzo.pieralisi@arm.com: patch split, typos fixing, rewrote the log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
2017-10-16 14:30:05 +01:00
Hanjun Guo
8c8df8dcd6 ACPI/IORT: Enable special index ITS group mappings for IORT nodes
IORT revision C introduced SMMUv3 and PMCG MSI support by adding
specific mapping entries in the SMMUv3/PMCG subtables to retrieve
the device ID and the ITS group it maps to for a given SMMUv3/PMCG
IORT node.

Introduce a mapping function (ie iort_get_id_mapping_index()), that
for a given IORT node looks up if an ITS specific ID mapping entry
exists and if so retrieve the corresponding mapping index in the IORT
node mapping array.

Since an ITS specific index mapping can be present for an IORT
node that is not a leaf node (eg SMMUv3 - to describe its own
ITS device ID) special handling is required for two steps mapping
cases such as PCI/NamedComponent--->SMMUv3--->ITS because the SMMUv3
ITS specific index mapping entry should be skipped to prevent the
IORT API from considering the mapping entry as a regular mapping one.

If we take the following IORT topology example:

|----------------------|
|  Root Complex Node   |
|----------------------|
|    map entry[x]      |
|----------------------|
|       id value       |
| output_reference     |
|---|------------------|
    |
    |   |----------------------|
    |-->|        SMMUv3        |
        |----------------------|
        |     SMMUv3 dev ID    |
        |     mapping index 0  |
        |----------------------|
        |      map entry[0]    |
        |----------------------|
        |       id value       |
        | output_reference-----------> ITS 1 (SMMU MSI domain)
        |----------------------|
        |      map entry[1]    |
        |----------------------|
        |       id value       |
        | output_reference-----------> ITS 2 (PCI MSI domain)
        |----------------------|

where the SMMUv3 ITS specific mapping entry is index 0 and it
represents the SMMUv3 ITS specific index mapping entry (describing its
own ITS device ID), we need to skip that mapping entry while carrying
out the Root Complex Node regular mappings to prevent erroneous
translations.

Reuse the iort_get_id_mapping_index() function to detect the ITS
specific mapping index for a specific IORT node and skip it in the IORT
mapping API (ie iort_node_map_id()) loop to prevent considering it a
normal PCI/Named Component ID mapping entry.

Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
[lorenzo.pieralisi@arm.com: split patch/rewrote commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
2017-10-16 14:29:55 +01:00
Hanjun Guo
0a71d8b95f ACPI/IORT: Look up IORT node through struct fwnode_handle pointer
Current IORT code provides a function (ie iort_get_fwnode())
which looks up a struct fwnode_handle pointer through a
struct acpi_iort_node pointer for SMMU components but it
lacks a function that implements the reverse look-up, namely
struct fwnode_handle* -> struct acpi_iort_node*.

Devices that are not IORT named components cannot be retrieved through
their associated IORT named component scan interface because they just
are not represented in the ACPI namespace; the reverse look-up is
therefore required for all platform devices that represent IORT nodes
(eg SMMUs) so that the struct acpi_iort_node* can be retrieved from the
struct device->fwnode pointer.

Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
[lorenzo.pieralisi@arm.com: re-indented/rewrote the commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
2017-10-16 14:29:45 +01:00
Lorenzo Pieralisi
896dd2c324 ACPI/IORT: Make platform devices initialization code SMMU agnostic
The way current IORT code initializes platform devices for SMMU nodes
is somewhat tied (mostly for naming convention) to the SMMU nodes
themselves but it need not be in that it is completely generic and
can easily be made so by structures renaming and code reshuffling.

Rework IORT platform devices initialization code to make the functions
and data structures SMMU agnostic.

No functional changes intended.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Sudeep Holla <sudeep.holla@arm.com>
2017-10-16 14:29:24 +01:00
Lorenzo Pieralisi
e3d4939267 ACPI/IORT: Improve functions return type/storage class specifier indentation
Some functions definition indentations are using a style that is frowned
upon with return value type/storage class specifier in a separate line.

Reindent the function definitions to fix them.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Sudeep Holla <sudeep.holla@arm.com>
2017-10-16 14:26:03 +01:00
Lorenzo Pieralisi
758081312e ACPI/IORT: Remove leftover ACPI_IORT_SMMU_V3_PXM_VALID guard
The conditional ACPI_IORT_SMMU_V3_PXM_VALID guard around
arm_smmu_v3_set_proximity() was added to manage a cross tree
ACPICA merge dependency; with ACPICA changes merged in:

commit c944230064 ("ACPICA: iasl: Update to IORT SMMUv3
disassembling")

the guard has become useless. Remove it.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com>
2017-10-16 14:25:52 +01:00
Arvind Yadav
ee10b9c927 acpi/arm64: pr_err() strings should end with newlines
pr_err() messages should terminated with a new-line to avoid
other messages being concatenated onto the end.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Hanjun Guo <hanjun.guo@linaro.org>
2017-10-16 14:25:43 +01:00
Julien Thierry
7b77452ec5 arm64: use WFE for long delays
The current delay implementation uses the yield instruction, which is a
hint that it is beneficial to schedule another thread. As this is a hint,
it may be implemented as a NOP, causing all delays to be busy loops. This
is the case for many existing CPUs.

Taking advantage of the generic timer sending periodic events to all
cores, we can use WFE during delays to reduce power consumption. This is
beneficial only for delays longer than the period of the timer event
stream.

If timer event stream is not enabled, delays will behave as yield/busy
loops.

Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-13 18:56:15 +01:00
Julien Thierry
ec5c8e429d arm_arch_timer: Expose event stream status
The arch timer configuration for a CPU might get reset after suspending
said CPU.

In order to reliably use the event stream in the kernel (e.g. for delays),
we keep track of the state where we can safely consider the event stream as
properly configured. After writing to cntkctl, we issue an ISB to ensure
that subsequent delay loops can rely on the event stream being enabled.

Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-13 18:55:05 +01:00
Mark Rutland
611a7bc74e arm64: docs: describe ELF hwcaps
We don't document our ELF hwcaps, leaving developers to interpret them
according to hearsay, guesswork, or (in exceptional cases) inspection of
the current kernel code.

This is less than optimal, and it would be far better if we had some
definitive description of each of the ELF hwcaps that developers could
refer to.

This patch adds a document describing the (native) arm64 ELF hwcaps.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Martin <Dave.Martin@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
[ Updated new hwcap entries in the document ]
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-11 15:28:40 +01:00
Suzuki K Poulose
f5e035f869 arm64: Expose support for optional ARMv8-A features
ARMv8-A adds a few optional features for ARMv8.2 and ARMv8.3.
Expose them to the userspace via HWCAPs and mrs emulation.

SHA2-512  - Instruction support for SHA512 Hash algorithm (e.g SHA512H,
	    SHA512H2, SHA512U0, SHA512SU1)
SHA3 	  - SHA3 crypto instructions (EOR3, RAX1, XAR, BCAX).
SM3	  - Instruction support for Chinese cryptography algorithm SM3
SM4 	  - Instruction support for Chinese cryptography algorithm SM4
DP	  - Dot Product instructions (UDOT, SDOT).

Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Dave Martin <dave.martin@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-11 15:28:40 +01:00
Ben Hutchings
0c3039ffc0 arm64: elf.h: Correct comment about READ_IMPLIES_EXEC propagation
Process personality always propagates across a fork(), but can change
at an execve().

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-09 10:00:23 +01:00
Matthieu CASTET
359be67862 dma mapping : export caller to vmallocinfo
For example on arm64 board, this add info to "user" entries in vmallocinfo

Before :
[...]
0xffffff8008997000 0xffffff80089d8000 266240 user
[...]

Afer :
[...]
0xffffff8008997000 0xffffff80089d8000 266240 atomic_pool_init+0x0/0x1d8 user
[...]

This help to debug mapping issues, and is consistent with others entries
(ioremap, vmalloc, ...) that already provide caller.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Matthieu CASTET <matthieu.castet@parrot.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-04 13:43:00 +01:00