Commit 6b8322576e ("MIPS: Force CPUs to lose FP context during mode
switches") ensures that we react to PR_SET_FP_MODE prctl syscalls
quickly by broadcasting an IPI in order to cause CPUs to lose FPU access
when necessary. Whilst it achieves that, unfortunately it causes all
sorts of strange race conditions because:
1) The IPI may arrive at a point where the FPU is in the process of
being enabled, but that process is not yet complete leading to a
state we aren't prepared to handle. For example:
[ 370.215903] do_cpu invoked from kernel context![#1]:
[ 370.221064] CPU: 0 PID: 963 Comm: fp-prctl Not tainted 4.9.0-rc5-00323-g210db32-dirty #226
[ 370.229420] task: a8000000fd672e00 task.stack: a8000000fd630000
[ 370.235399] $ 0 : 0000000000000000 0000000000000001 0000000000000001 a8000000fd630000
[ 370.243882] $ 4 : a8000000fd672e00 0000000000000000 0000000000000453 0000000000000000
[ 370.252317] $ 8 : 0000000000000000 a8000000fd637c28 1000000000000000 0000000000000010
[ 370.260753] $12 : 00000000140084e0 ffffffff80109c00 0000000000000000 0000000000000002
[ 370.269179] $16 : ffffffff8092f080 a8000000fd672e00 ffffffff80107fe8 a8000000fd485000
[ 370.277612] $20 : ffffffff8084d328 ffffffff80940000 0000000000000009 ffffffff80930000
[ 370.286038] $24 : 0000000000000000 900000001612048c
[ 370.294476] $28 : a8000000fd630000 a8000000fd637ac0 ffffffff80937300 ffffffff8010807c
[ 370.302909] Hi : 0000000000000000
[ 370.306595] Lo : 0000000000000200
[ 370.310376] epc : ffffffff80115d38 _save_fp+0x10/0xa0
[ 370.315784] ra : ffffffff8010807c prepare_for_fp_mode_switch+0x94/0x1b0
[ 370.322707] Status: 140084e2 KX SX UX KERNEL EXL
[ 370.327980] Cause : 1080002c (ExcCode 0b)
[ 370.332091] PrId : 0001a428 (MIPS P6600)
[ 370.336179] Modules linked in:
[ 370.339486] Process fp-prctl (pid: 963, threadinfo=a8000000fd630000, task=a8000000fd672e00, tls=00000000756e67d0)
[ 370.349724] Stack : 0000000000000000 a8000000fd557dc0 0000000000000000 ffffffff801ca8e0
[ 370.358161] 0000000000000000 a8000000fd637b9c 0000000000000009 ffffffff80923780
[ 370.366575] ffffffff80850000 ffffffff8011610c 00000000000000b8 ffffffff801a5084
[ 370.374989] ffffffff8084a370 ffffffff8084a388 ffffffff80923780 ffffffff80923828
[ 370.383395] 0000000000010000 ffffffff809237a8 0000000000020000 ffffffff80a40000
[ 370.391817] 000000000000007c 00000000004a0000 00000000756dedd0 ffffffff801a5188
[ 370.400230] a800000002014900 0000000000000001 ffffffff80923780 0000000080923828
[ 370.408644] ffffffff80923780 ffffffff80923780 ffffffff80923828 ffffffff801a521c
[ 370.417066] ffffffff80923780 ffffffff80923828 0000000000010000 ffffffff801a8f84
[ 370.425472] ffffffff80a40000 a8000000fd637c20 ffffffff80a39240 0000000000000001
[ 370.433885] ...
[ 370.436562] Call Trace:
[ 370.439222] [<ffffffff80115d38>] _save_fp+0x10/0xa0
[ 370.444305] [<ffffffff8010807c>] prepare_for_fp_mode_switch+0x94/0x1b0
[ 370.451035] [<ffffffff801ca8e0>] flush_smp_call_function_queue+0xf8/0x230
[ 370.457991] [<ffffffff8011610c>] ipi_call_interrupt+0xc/0x20
[ 370.463814] [<ffffffff801a5084>] __handle_irq_event_percpu+0xc4/0x1a8
[ 370.470404] [<ffffffff801a5188>] handle_irq_event_percpu+0x20/0x68
[ 370.476734] [<ffffffff801a521c>] handle_irq_event+0x4c/0x88
[ 370.482486] [<ffffffff801a8f84>] handle_edge_irq+0x12c/0x210
[ 370.488316] [<ffffffff801a47a0>] generic_handle_irq+0x38/0x48
[ 370.494280] [<ffffffff804a2dbc>] gic_handle_shared_int+0x194/0x268
[ 370.500616] [<ffffffff801a47a0>] generic_handle_irq+0x38/0x48
[ 370.506529] [<ffffffff80107e60>] do_IRQ+0x18/0x28
[ 370.511445] [<ffffffff804a1524>] plat_irq_dispatch+0xc4/0x140
[ 370.517339] [<ffffffff80106230>] ret_from_irq+0x0/0x4
[ 370.522583] [<ffffffff8010fad4>] do_ri+0x4fc/0x7e8
[ 370.527546] [<ffffffff80106220>] ret_from_exception+0x0/0x10
2) The IPI may arrive during kernel use of the FPU, since we generally
only disable preemption around use of the FPU & leave interrupts
enabled. This can lead to us unexpectedly losing access to the FPU
in places where it previously had not been possible. For example:
do_cpu invoked from kernel context![#2]:
CPU: 2 PID: 7338 Comm: fp-prctl Tainted: G D 4.7.0-00424-g49b0c82
#2
task: 838e4000 ti: 88d38000 task.ti: 88d38000
$ 0 : 00000000 00000001 ffffffff 88d3fef8
$ 4 : 838e4000 88d38004 00000000 00000001
$ 8 : 3400fc01 801f8020 808e9100 24000000
$12 : dbffffff 807b69d8 807b0000 00000000
$16 : 00000000 80786150 00400fc4 809c0398
$20 : 809c0338 0040273c 88d3ff28 808e9d30
$24 : 808e9d30 00400fb4
$28 : 88d38000 88d3fe88 00000000 8011a2ac
Hi : 0040273c
Lo : 88d3ff28
epc : 80114178 _restore_fp+0x10/0xa0
ra : 8011a2ac mipsr2_decoder+0xd5c/0x1660
Status: 1400fc03 KERNEL EXL IE
Cause : 1080002c (ExcCode 0b)
PrId : 0001a920 (MIPS I6400)
Modules linked in:
Process fp-prctl (pid: 7338, threadinfo=88d38000, task=838e4000, tls=766527d0)
Stack : 00000000 00000000 00000000 88d3fe98 00000000 00000000 809c0398 809c0338
808e9100 00000000 88d3ff28 00400fc4 00400fc4 0040273c 7fb69e18 004a0000
004a0000 004a0000 7664add0 8010de18 00000000 00000000 88d3fef8 88d3ff28
808e9100 00000000 766527d0 8010e534 000c0000 85755000 8181d580 00000000
00000000 00000000 004a0000 00000000 766527d0 7fb69e18 004a0000 80105c20
...
Call Trace:
[<80114178>] _restore_fp+0x10/0xa0
[<8011a2ac>] mipsr2_decoder+0xd5c/0x1660
[<8010de18>] do_ri+0x90/0x6b8
[<80105c20>] ret_from_exception+0x0/0x10
At first glance a simple fix may seem to be to disable interrupts around
kernel use of the FPU rather than merely preemption, however this would
introduce further overhead outside of the mode switch path & doesn't
solve the third problem:
3) The IPI may arrive whilst the kernel is running code that will lead
to a preempt_disable() call & FPU usage soon. If this happens then
the IPI will be serviced & we'll proceed to enable an FPU whilst the
mode switch is in progress, leading to strange & inconsistent
behaviour.
Further to all of this is a separate but related problem:
4) There are various paths through which we may enable the FPU without
the user having triggered a coprocessor 1 disabled exception. These
paths are those in which we emulate instructions & then enable the
FPU with the expectation that the user might execute an FP
instruction shortly afterwards. However these paths have not
previously checked whether an FP mode switch is underway for the
task, and therefore could enable the FPU whilst such a mode switch
is in progress leading to strange & inconsistent behaviour for user
code.
This patch fixes all of the above by taking a step back & re-examining
our approach to FP mode switches. Up until now we have taken these basic
steps:
a) Prevent any threads that are part of the affected process from being
able to obtain ownership of the FPU.
b) Cause any threads that are part of the affected process and already
have ownership of an FPU to lose it.
c) Set the thread flags for each thread that is part of the affected
process to reflect the new FP mode.
d) Allow threads to obtain ownership of the FPU again.
This approach is however more complex than necessary. All that we really
require is that the mode switch has occurred for all threads that are
part of the affected process before mips_set_process_fp_mode(), and thus
the PR_SET_FP_MODE prctl() syscall, returns. This doesn't require that
we stop threads from owning or using an FPU whilst a mode switch occurs,
only that we force them to relinquish it after the mode switch has
occurred such that they next own an FPU with the correct mode
configured. Our basic steps therefore simplify to:
A) Set the thread flags for each thread that is part of the affected
process to reflect the new FP mode.
B) Cause any threads that are part of the affected process and already
have ownership of an FPU to lose it.
We implement B) by forcing each CPU which might be running a thread
which is part of the affected process to schedule a no-op function,
which causes the affected thread to lose its FPU ownership when it is
descheduled.
The end result is simpler FP mode switching with less overhead in the
FPU enable path (ie. enable_restore_fp_context()) and fewer moving
parts.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: 9791554b45 ("MIPS,prctl: add PR_[GS]ET_FP_MODE prctl options for MIPS")
Fixes: 6b8322576e ("MIPS: Force CPUs to lose FP context during mode switches")
Cc: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: stable <stable@vger.kernel.org> # v4.0+
Some of the atomics return the result of a test applied after the atomic
operation, and almost all architectures implement these as trivial
wrappers around the underlying atomic. Specifically:
* <atomic>_inc_and_test(v) is (<atomic>_inc_return(v) == 0)
* <atomic>_dec_and_test(v) is (<atomic>_dec_return(v) == 0)
* <atomic>_sub_and_test(i, v) is (<atomic>_sub_return(i, v) == 0)
* <atomic>_add_negative(i, v) is (<atomic>_add_return(i, v) < 0)
Rather than have these definitions duplicated in all architectures, with
minor inconsistencies in formatting and documentation, let's make these
operations optional, with default fallbacks as above. Implementations
must now provide a preprocessor symbol.
The instrumented atomics are updated accordingly.
Both x86 and m68k have custom implementations, which are left as-is,
given preprocessor symbols to avoid being overridden.
There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Palmer Dabbelt <palmer@sifive.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/lkml/20180621121321.4761-16-mark.rutland@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Architectures with atomic64_fetch_add_unless() provide a preprocessor
symbol if they do so, and all other architectures have trivial C
implementations of atomic64_add_unless() which are near-identical.
Let's unify the trivial definitions of atomic64_fetch_add_unless() in
<linux/atomic.h>, so that we always have both
atomic64_fetch_add_unless() and atomic64_add_unless() with less
boilerplate code.
This means that atomic64_add_unless() is always implemented in core
code, and the instrumented atomics are updated accordingly.
There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/lkml/20180621121321.4761-15-mark.rutland@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Several architectures these have a near-identical implementation based
on atomic_read() and atomic_cmpxchg() which we can instead define in
<linux/atomic.h>, so let's do so, using something close to the existing
x86 implementation with try_cmpxchg().
Where an architecture provides its own atomic_fetch_add_unless(), it
must define a preprocessor symbol for it. The instrumented atomics are
updated accordingly.
Note that arch/arc's existing atomic_fetch_add_unless() had redundant
barriers, as these are already present in its atomic_cmpxchg()
implementation.
There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Palmer Dabbelt <palmer@sifive.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vineet Gupta <vgupta@synopsys.com>
Link: https://lore.kernel.org/lkml/20180621121321.4761-7-mark.rutland@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We define a trivial fallback for atomic_inc_not_zero(), but don't do
the same for atomic64_inc_not_zero(), leading most architectures to
define the same boilerplate.
Let's add a fallback in <linux/atomic.h>, and remove the redundant
implementations. Note that atomic64_add_unless() is always defined in
<linux/atomic.h>, and promotes its arguments to the requisite types, so
we need not do this explicitly.
There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Palmer Dabbelt <palmer@sifive.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/lkml/20180621121321.4761-6-mark.rutland@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
While __atomic_add_unless() was originally intended as a building-block
for atomic_add_unless(), it's now used in a number of places around the
kernel. It's the only common atomic operation named __atomic*(), rather
than atomic_*(), and for consistency it would be better named
atomic_fetch_add_unless().
This lack of consistency is slightly confusing, and gets in the way of
scripting atomics. Given that, let's clean things up and promote it to
an official part of the atomics API, in the form of
atomic_fetch_add_unless().
This patch converts definitions and invocations over to the new name,
including the instrumented version, using the following script:
----
git grep -w __atomic_add_unless | while read line; do
sed -i '{s/\<__atomic_add_unless\>/atomic_fetch_add_unless/}' "${line%%:*}";
done
git grep -w __arch_atomic_add_unless | while read line; do
sed -i '{s/\<__arch_atomic_add_unless\>/arch_atomic_fetch_add_unless/}' "${line%%:*}";
done
----
Note that we do not have atomic{64,_long}_fetch_add_unless(), which will
be introduced by later patches.
There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Palmer Dabbelt <palmer@sifive.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/lkml/20180621121321.4761-2-mark.rutland@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The erratum and workaround are described by BCM5300X-ES300-RDS.pdf as
below.
R10: PCIe Transactions Periodically Fail
Description: The BCM5300X PCIe does not maintain transaction ordering.
This may cause PCIe transaction failure.
Fix Comment: Add a dummy PCIe configuration read after a PCIe
configuration write to ensure PCIe configuration access
ordering. Set ES bit of CP0 configu7 register to enable
sync function so that the sync instruction is functional.
Resolution: hndpci.c: extpci_write_config()
hndmips.c: si_mips_init()
mipsinc.h CONF7_ES
This is fixed by the CFE MIPS bcmsi chipset driver also for BCM47XX.
Also the dummy PCIe configuration read is already implemented in the
Linux BCMA driver.
Enable ExternalSync in Config7 when CONFIG_BCMA_DRIVER_PCI_HOSTMODE=y
too so that the sync instruction is externalised.
Signed-off-by: Tokunori Ikegami <ikegami@allied-telesis.co.jp>
Reviewed-by: Paul Burton <paul.burton@mips.com>
Acked-by: Hauke Mehrtens <hauke@hauke-m.de>
Cc: Chris Packham <chris.packham@alliedtelesis.co.nz>
Cc: Rafał Miłecki <zajec5@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/19461/
Signed-off-by: James Hogan <jhogan@kernel.org>
Pull MIPS updates from James Hogan:
"These are the main MIPS changes for 4.18.
Rough overview:
- MAINTAINERS: Add Paul Burton as MIPS co-maintainer
- Misc: Generic compiler intrinsics, Y2038 improvements, Perf+MT fixes
- Platform support: Netgear WNR1000 V3, Microsemi Ocelot integrated
switch, Ingenic watchdog cleanups
More detailed summary:
Maintainers:
- Add Paul Burton as MIPS co-maintainer, as I soon won't have access
to much MIPS hardware, nor enough time to properly maintain MIPS on
my own.
Miscellaneous:
- Use generic GCC library routines from lib/
- Add notrace to generic ucmpdi2 implementation
- Rename compiler intrinsic selects to GENERIC_LIB_*
- vmlinuz: Use generic ashldi3
- y2038: Convert update/read_persistent_clock() to *_clock64()
- sni: Remove read_persistent_clock()
- perf: Fix perf with MT counting other threads
- Probe for per-TC perf counters in cpu-probe.c
- Use correct VPE ID for VPE tracing
Minor cleanups:
- Avoid unneeded built-in.a in DTS dirs
- sc-debugfs: Re-use kstrtobool_from_user
- memset.S: Reinstate delay slot indentation
- VPE: Fix spelling "uneeded" -> "Unneeded"
Platform support:
BCM47xx:
- Add support for Netgear WNR1000 V3
- firmware: Support small NVRAM partitions
- Use __initdata for LEDs platform data
Ingenic:
- Watchdog driver & platform code improvements:
- Disable clock after stopping counter
- Use devm_* functions
- Drop module remove function
- Move platform reset code to restart handler in driver
- JZ4740: Convert watchdog instantiation to DT
- JZ4780: Fix watchdog DT node
- qi_lb60_defconfig: Enable watchdog driver
Microsemi:
- Ocelot: Add support for integrated switch
- pcb123: Connect phys to ports"
* tag 'mips_4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (30 commits)
MAINTAINERS: Add Paul Burton as MIPS co-maintainer
MIPS: ptrace: Make FPU context layout comments match reality
MIPS: memset.S: Reinstate delay slot indentation
MIPS: perf: Fix perf with MT counting other threads
MIPS: perf: Use correct VPE ID when setting up VPE tracing
MIPS: perf: More robustly probe for the presence of per-tc counters
MIPS: Probe for MIPS MT perf counters per TC
MIPS: mscc: Connect phys to ports on ocelot_pcb123
MIPS: mscc: Add switch to ocelot
MIPS: JZ4740: Drop old platform reset code
MIPS: qi_lb60: Enable the jz4740-wdt driver
MIPS: JZ4780: dts: Fix watchdog node
MIPS: JZ4740: dts: Add bindings for the jz4740-wdt driver
watchdog: JZ4740: Drop module remove function
watchdog: JZ4740: Register a restart handler
watchdog: JZ4740: Use devm_* functions
watchdog: JZ4740: Disable clock after stopping counter
MIPS: VPE: Fix spelling mistake: "uneeded" -> "unneeded"
MIPS: Re-use kstrtobool_from_user()
MIPS: Convert update_persistent_clock() to update_persistent_clock64()
...
Pull timers and timekeeping updates from Thomas Gleixner:
- Core infrastucture work for Y2038 to address the COMPAT interfaces:
+ Add a new Y2038 safe __kernel_timespec and use it in the core
code
+ Introduce config switches which allow to control the various
compat mechanisms
+ Use the new config switch in the posix timer code to control the
32bit compat syscall implementation.
- Prevent bogus selection of CPU local clocksources which causes an
endless reselection loop
- Remove the extra kthread in the clocksource code which has no value
and just adds another level of indirection
- The usual bunch of trivial updates, cleanups and fixlets all over the
place
- More SPDX conversions
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
clocksource/drivers/mxs_timer: Switch to SPDX identifier
clocksource/drivers/timer-imx-tpm: Switch to SPDX identifier
clocksource/drivers/timer-imx-gpt: Switch to SPDX identifier
clocksource/drivers/timer-imx-gpt: Remove outdated file path
clocksource/drivers/arc_timer: Add comments about locking while read GFRC
clocksource/drivers/mips-gic-timer: Add pr_fmt and reword pr_* messages
clocksource/drivers/sprd: Fix Kconfig dependency
clocksource: Move inline keyword to the beginning of function declarations
timer_list: Remove unused function pointer typedef
timers: Adjust a kernel-doc comment
tick: Prefer a lower rating device only if it's CPU local device
clocksource: Remove kthread
time: Change nanosleep to safe __kernel_* types
time: Change types to new y2038 safe __kernel_* types
time: Fix get_timespec64() for y2038 safe compat interfaces
time: Add new y2038 safe __kernel_timespec
posix-timers: Make compat syscalls depend on CONFIG_COMPAT_32BIT_TIME
time: Introduce CONFIG_COMPAT_32BIT_TIME
time: Introduce CONFIG_64BIT_TIME in architectures
compat: Enable compat_get/put_timespec64 always
...
Processors implementing the MIPS MT ASE may have performance counters
implemented per core or per TC. Processors implemented by MIPS
Technologies signify presence per TC through a bit in the implementation
specific Config7 register. Currently the code which probes for their
presence blindly reads a magic number corresponding to this bit, despite
it potentially having a different meaning in the CPU implementation.
Since CPU features are generally detected by cpu-probe.c, perform the
detection here instead. Introduce cpu_set_mt_per_tc_perf which checks
the bit in config7 and call it from MIPS CPUs known to implement this
bit and the MT ASE, specifically, the 34K, 1004K and interAptiv.
Once the presence of the per-tc counter is indicated in cpu_data, tests
for it can be updated to use this flag.
Suggested-by: James Hogan <jhogan@kernel.org>
Signed-off-by: Matt Redfearn <matt.redfearn@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Matt Redfearn <matt.redfearn@mips.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Maciej W. Rozycki <macro@mips.com>
Cc: linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/19136/
Signed-off-by: James Hogan <jhogan@kernel.org>
Since struct timespec is not y2038 safe on 32bit machines, this patch
converts update_persistent_clock() to update_persistent_clock64() using
struct timespec64.
The rtc_mips_set_time() and rtc_mips_set_mmss() interfaces were using
'unsigned long' type that is not y2038 safe on 32bit machines, moreover
there is only one platform implementing rtc_mips_set_time() and two
platforms implementing rtc_mips_set_mmss(), so we can just make them each
implement update_persistent_clock64() directly, to get that helper out
of the common mips code by removing rtc_mips_set_time() and
rtc_mips_set_mmss() interfaces.
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@linux-mips.org
Signed-off-by: James Hogan <jhogan@kernel.org>
This was used by the ide, scsi and networking code in the past to
determine if they should bounce payloads. Now that the dma mapping
always have to support dma to all physical memory (thanks to swiotlb
for non-iommu systems) there is no need to this crude hack any more.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Palmer Dabbelt <palmer@sifive.com> (for riscv)
Reviewed-by: Jens Axboe <axboe@kernel.dk>
This adds support for detecting this model board and registers some LEDs
and buttons.
There are two uncommon things regarding this device:
1) It can use two different "board_id" ID values.
Unit I have uses "U12H139T00_NETGEAR" value. This magic is also used
in firmware file header. There are two reports (one from an OpenWrt
user) of a different "U12H139T50_NETGEAR" magic though.
2) Power LEDs share GPIOs with buttons.
Amber one seems to share GPIO 2 with WPS button and green one seems
to share GPIO 3 with reset button. It remains unknown how to support
them and handle buttons at the same time. For that reason they aren't
added to the list of supported LEDs.
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/19004/
Signed-off-by: James Hogan <jhogan@kernel.org>
Pull MIPS fixes from James Hogan:
- io: Add barriers to read*() & write*()
- dts: Fix boston PCI bus DTC warnings (4.17)
- memset: Several corner case fixes (one 3.10, others longer)
* tag 'mips_fixes_4.17_1' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/mips:
MIPS: uaccess: Add micromips clobbers to bzero invocation
MIPS: memset.S: Fix clobber of v1 in last_fixup
MIPS: memset.S: Fix return of __clear_user from Lpartial_fixup
MIPS: memset.S: EVA & fault support for small_memset
MIPS: dts: Boston: Fix PCI bus dtc warnings:
MIPS: io: Add barrier after register read in readX()
MIPS: io: Prevent compiler reordering writeX()
MIPS is the weirdest case for sysvipc, because each of the
three data structures is done differently:
* msqid64_ds has padding in the right place so we could in theory
extend this one to just have 64-bit values instead of time_t.
As this does not work for most of the other combinations,
we just handle it in the common manner though.
* semid64_ds has no padding for 64-bit time_t, but has two reserved
'long' fields, which are sufficient to extend the sem_otime
and sem_ctime fields to 64 bit. In order to do this, the libc
implementation will have to copy the data into another structure
that has the fields in a different order. MIPS is the only
architecture with this problem, so this is best done in MIPS
specific libc code.
* shmid64_ds is slightly worse than that, because it has three
time_t fields but only two unused 32-bit words. As a workaround,
we extend each field only by 16 bits, ending up with 48-bit
timestamps that user space again has to work around by itself.
The compat versions of the data structures are changed in the
same way.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
While a barrier is present in the writeX() functions before the register
write, a similar barrier is missing in the readX() functions after the
register read. This could allow memory accesses following readX() to
observe stale data.
Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/19069/
[jhogan@kernel.org: Tidy commit message]
Signed-off-by: James Hogan <jhogan@kernel.org>
Pull MIPS updates from James Hogan:
"These are the main MIPS changes for 4.17. Rough overview:
(1) generic platform: Add support for Microsemi Ocelot SoCs
(2) crypto: Add CRC32 and CRC32C HW acceleration module
(3) Various cleanups and misc improvements
More detailed summary:
Miscellaneous:
- hang more efficiently on halt/powerdown/restart
- pm-cps: Block system suspend when a JTAG probe is present
- expand make help text for generic defconfigs
- refactor handling of legacy defconfigs
- determine the entry point from the ELF file header to fix microMIPS
for certain toolchains
- introduce isa-rev.h for MIPS_ISA_REV and use to simplify other code
Minor cleanups:
- DTS: boston/ci20: Unit name cleanups and correction
- kdump: Make the default for PHYSICAL_START always 64-bit
- constify gpio_led in Alchemy, AR7, and TXX9
- silence a couple of W=1 warnings
- remove duplicate includes
Platform support:
Generic platform:
- add support for Microsemi Ocelot
- dt-bindings: Add vendor prefix for Microsemi Corporation
- dt-bindings: Add bindings for Microsemi SoCs
- add ocelot SoC & PCB123 board DTS files
- MAINTAINERS: Add entry for Microsemi MIPS SoCs
- enable crc32-mips on r6 configs
ath79:
- fix AR724X_PLL_REG_PCIE_CONFIG offset
BCM47xx:
- firmware: Use mac_pton() for MAC address parsing
- add Luxul XAP1500/XWR1750 WiFi LEDs
- use standard reset button for Luxul XWR-1750
BMIPS:
- enable CONFIG_BRCMSTB_PM in bmips_stb_defconfig for build coverage
- add STB PM, wake-up timer, watchdog DT nodes
Octeon:
- drop '.' after newlines in printk calls
ralink:
- pci-mt7621: Enable PCIe on MT7688"
* tag 'mips_4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/mips: (37 commits)
MIPS: BCM47XX: Use standard reset button for Luxul XWR-1750
MIPS: BCM47XX: Add Luxul XAP1500/XWR1750 WiFi LEDs
MIPS: Make the default for PHYSICAL_START always 64-bit
MIPS: Use the entry point from the ELF file header
MAINTAINERS: Add entry for Microsemi MIPS SoCs
MIPS: generic: Add support for Microsemi Ocelot
MIPS: mscc: Add ocelot PCB123 device tree
MIPS: mscc: Add ocelot dtsi
dt-bindings: mips: Add bindings for Microsemi SoCs
dt-bindings: Add vendor prefix for Microsemi Corporation
MIPS: ath79: Fix AR724X_PLL_REG_PCIE_CONFIG offset
MIPS: pci-mt7620: Enable PCIe on MT7688
MIPS: pm-cps: Block system suspend when a JTAG probe is present
MIPS: VDSO: Replace __mips_isa_rev with MIPS_ISA_REV
MIPS: BPF: Replace __mips_isa_rev with MIPS_ISA_REV
MIPS: cpu-features.h: Replace __mips_isa_rev with MIPS_ISA_REV
MIPS: Introduce isa-rev.h to define MIPS_ISA_REV
MIPS: Hang more efficiently on halt/powerdown/restart
FIRMWARE: bcm47xx_nvram: Replace mac address parsing
MIPS: BMIPS: Add Broadcom STB watchdog nodes
...
