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perf trace supports --no-syscalls option but it's not listed in the man
page. (Though, I see an example using --no-syscalls in EXAMPLES
section.)
Committer note:
The --no-syscalls option tells 'perf trace' not to automagically ask for
raw_syscalls:sys_{enter,exit} to then format it in a strace like way.
This become more used as 'perf trace' got support for arbitrary events,
such as tracepoints, so more and more we use:
# perf trace --no-syscalls -e nmi:*
0.000 nmi:nmi_handler:perf_event_nmi_handler() delta_ns: 36649 handled: 1)
0.019 nmi:nmi_handler:nmi_cpu_backtrace_handler() delta_ns: 2907 handled: 0)
0.676 nmi:nmi_handler:perf_event_nmi_handler() delta_ns: 9401 handled: 1)
0.680 nmi:nmi_handler:nmi_cpu_backtrace_handler() delta_ns: 288 handled: 0)
0.701 nmi:nmi_handler:perf_event_nmi_handler() delta_ns: 4977 handled: 1)
0.703 nmi:nmi_handler:nmi_cpu_backtrace_handler() delta_ns: 67 handled: 0)
0.736 nmi:nmi_handler:perf_event_nmi_handler() delta_ns: 8549 handled: 1)
^C#
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexis Berlemont <alexis.berlemont@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1492063332-5745-1-git-send-email-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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(This is a patch has been sitting in the Intel CQM/CMT driver series for
a while, despite not depend on it. Sending it now independently since
the series is being discarded.)
When an event is in error state, read() returns 0 instead of sizeof()
buffer. In certain modes, such as interval printing, ignoring the 0
return value may cause bogus count deltas to be computed and thus
invalid results printed.
This patch fixes this problem by modifying read_counters() to mark the
event as not scaled (scaled = -1) to force the printout routine to show
<NOT COUNTED>.
Signed-off-by: Stephane Eranian <eranian@google.com>
Reviewed-by: David Carrillo-Cisneros <davidcc@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20170412182301.44406-1-davidcc@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The pseries platform supports Power4 and later CPUs, all of which are
multithreaded and/or multicore.
In practice no one ever builds a SMP=n kernel for these machines. So as
we did for powernv, have the pseries platform imply SMP=y.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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The powernv platform supports Power7 and later CPUs, all of which are
multithreaded and multicore.
As such we never build a SMP=n kernel for those machines, other than
possibly for debugging or running in a simulator.
In the debugging case we can get a similar effect by booting with
nr_cpus=1, or there's always the option of building a custom kernel with
SMP hacked out.
For running in simulators the code size reduction from building without
SMP is not particularly important, what matters is the number of
instructions executed. A quick test shows that a SMP=y kernel takes ~6%
more instructions to boot to a shell. Booting with nr_cpus=1 recovers
about half that deficit.
On the flip side, keeping the SMP=n kernel building can be a pain at
times. And although we've mostly kept it building in recent years, no
one is regularly testing that the SMP=n kernel actually boots and works
well on these machines.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Of the 64-bit Book3S platforms, only powermac supports booting on an
actual non-SMP system. The other platforms can be built with SMP
disabled, but it doesn't make a lot of sense given the CPUs they support
are all multicore or multithreaded.
So give platforms the option of forcing SMP=y.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Currently powerpc's asm/io.h includes linux/io.h, and linux/io.h
includes asm/io.h.
This can cause problems because depending on which is included first the
order of definitions between the two files will change.
The include of linux/io.h was added back in 2008 in commit b41e5fffe8b8
("[POWERPC] devres: Add devm_ioremap_prot()"). It's not entirely clear
it was needed then, but devm_ioremap_prot() has since been removed
entirely as unused, in dedd24a12fe6 ("powerpc: Remove unused
devm_ioremap_prot()").
So it seems to be unnecessary and can potentially cause problems, so
remove the include of linux/io.h from asm/io.h
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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POWER9 requires msgsync for receiver-side synchronization, and a DD1
workaround restricts IPIs to core-local.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Drop no longer needed asm feature macro changes]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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IPIs are a pretty hot path and we already have the ability to do asm feature
patching, so use it.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Change log detail]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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POWER9 changes requirements and adds new instructions for
synchronization.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Change the doorbell callers to know about their msgsnd addressing,
rather than have them set a per-cpu target data tag at boot that gets
sent to the cause_ipi functions. The data is only used for doorbell IPI
functions, no other IPI types, so it makes sense to keep that detail
local to doorbell.
Have the platform code understand doorbell IPIs, rather than the
interrupt controller code understand them. Platform code can look at
capabilities it has available and decide which to use.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Add the bit definition and use it in facility_unavailable_exception() so we can
intelligently report the cause if we take a fault for SCV. This doesn't actually
enable SCV.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Drop whitespace changes to the existing entries, flush out change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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We have a #define for it, so use it.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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The new Coherent Accelerator Interface Architecture, level 2, for the
IBM POWER9 brings new content and features:
- POWER9 Service Layer
- Registers
- Radix mode
- Process element entry
- Dedicated-Shared Process Programming Model
- Translation Fault Handling
- CAPP
- Memory Context ID
If a valid mm_struct is found the memory context id is used for each
transaction associated with the process handle. The PSL uses the
context ID to find the corresponding process element.
Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
[mpe: Fixup comment formatting, unsplit long strings]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Point out the specific Coherent Accelerator Interface Architecture,
level 1, registers.
Code and functions specific to PSL8 (CAIA1) must be framed.
Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
[mpe: Don't split long strings, it makes them hard to grep for]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Rename a few functions, changing the '_psl' suffix to '_psl8', to make
clear that the implementation is psl8 specific.
Those functions will have an equivalent implementation for the psl9 in
a later patch.
Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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The service layer API (in cxl.h) lists some low-level functions whose
implementation is different on PSL8, PSL9 and XSL:
- Init implementation for the adapter and the afu.
- Invalidate TLB/SLB.
- Attach process for dedicated/directed models.
- Handle psl interrupts.
- Debug registers for the adapter and the afu.
- Traces.
Each environment implements its own functions, and the common code uses
them through function pointers, defined in cxl_service_layer_ops.
Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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The mm_struct corresponding to the current task is acquired each time
an interrupt is raised. So to simplify the code, we only get the
mm_struct when attaching an AFU context to the process.
The mm_count reference is increased to ensure that the mm_struct can't
be freed. The mm_struct will be released when the context is detached.
A reference on mm_users is not kept to avoid a circular dependency if
the process mmaps its cxl mmio and forget to unmap before exiting.
The field glpid (pid of the group leader associated with the pid), of
the structure cxl_context, is removed because it's no longer useful.
Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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The two previously fields pid and tid, located in the structure
cxl_irq_info, are only used in the guest environment. To avoid confusion,
it's not necessary to fill the fields in the bare-metal environment.
Pid_tid is now renamed to 'reserved' to avoid undefined behavior on
bare-metal. The PSL Process and Thread Identification Register
(CXL_PSL_PID_TID_An) is only used when attaching a dedicated process
for PSL8 only. This register goes away in CAIA2.
Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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This bit is used to cause a flash image load for programmable
CAIA-compliant implementation. If this bit is set to ‘0’, a power
cycle of the adapter is required to load a programmable CAIA-com-
pliant implementation from flash.
This field will be used by the following patches.
Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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The driver doesn't have a struct of_device_id table but supported devices
are registered via Device Trees. This is working on the assumption that a
I2C device registered via OF will always match a legacy I2C device ID and
that the MODALIAS reported will always be of the form i2c:<device>.
But this could change in the future so the correct approach is to have an
OF device ID table if the devices are registered via OF.
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
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The I2C device ID entries set a .driver_data but this data is never
looked up by the driver. So don't set it and also remove the enum.
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
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The switch that conditionally sets CPUPOWER_CAP_HAS_TURBO_RATIO and
CPUPOWER_CAP_IS_SNB flags is missing a break, so all cores get both
flags set and an assumed base clock of 100 MHz for turbo values.
Reported-by: GSR <gsr.bugs@infernal-iceberg.com>
Tested-by: GSR <gsr.bugs@infernal-iceberg.com>
References: https://bugs.debian.org/859978
Fixes: 8fb2e440b223 (cpupower: Show Intel turbo ratio support via ...)
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux
Pull turbostat utility fixes for v4.11 from Len Brown.
* 'turbostat' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
tools/power turbostat: update version number
tools/power turbostat: fix impossibly large CPU%c1 value
tools/power turbostat: turbostat.8 add missing column definitions
tools/power turbostat: update HWP dump to decimal from hex
tools/power turbostat: enable package THERM_INTERRUPT dump
tools/power turbostat: show missing Core and GFX power on SKL and KBL
tools/power turbostat: bugfix: GFXMHz column not changing
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In case wil6210 resume fails, wil6210 suspend function will try
to access the suspended device in the next kernel suspend.
To prevent that, add wil_status_suspended flag to indicate if the
device is already suspended and clear it only if the resume succeeds.
Signed-off-by: Maya Erez <qca_merez@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
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Array index 'i' is used before limits check.
Fix this by doing limits check first.
Signed-off-by: Dedy Lansky <qca_dlansky@qca.qualcomm.com>
Signed-off-by: Maya Erez <qca_merez@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
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debugfs ioblob function is called by the FW logs scripts
to copy the FW logs via PCIe.
As the FW logs collection is done in parallel to the operational
11AD actions, the HALP voting can take place during 11AD reset flow
and other sensitive scenarios.
To prevent that, remove HALP voting from the ioblob function.
Signed-off-by: Maya Erez <qca_merez@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
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In case count is not multiple of 4, there is a read access in
wil_memcpy_toio_32() from outside src buffer boundary.
In wil_memcpy_fromio_32(), in case count is not multiple of 4, there is
a write access to outside dst io memory boundary.
Fix these issues with proper handling of the last 1 to 4 copied bytes.
Signed-off-by: Dedy Lansky <qca_dlansky@qca.qualcomm.com>
Signed-off-by: Maya Erez <qca_merez@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
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Driver fails to load FW for sparrow D0 devices in some cases.
Fix this by returning correct value from wil_fw_verify_file_exists
when D0 FW file is not detected for any reason.
Signed-off-by: Hamad Kadmany <qca_hkadmany@qca.qualcomm.com>
Signed-off-by: Maya Erez <qca_merez@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
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During the suspend flow, wil6210 HW can send sporadic interrupts,
while PCIe bus is not operational.
To prevent that, keep the interrupts disabled during the suspend
flow and re-enable them only after PCIe enablement in resume.
Signed-off-by: Maya Erez <qca_merez@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
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Existing code that ignores connection events during
reset flow will never take effect since it locks the
same mutex taken by the reset flow.
In addition, in case of unsolicited disconnect events ignore
those as well since device is about to get reset.
Signed-off-by: Hamad Kadmany <qca_hkadmany@qca.qualcomm.com>
Signed-off-by: Maya Erez <qca_merez@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
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Align to latest version of the auto generated wmi file
describing the interface with FW
Signed-off-by: Dedy Lansky <qca_dlansky@qca.qualcomm.com>
Signed-off-by: Maya Erez <qca_merez@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
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The 11ad spec requires 11ad devices to be able to receive 8KB
packets over the air. Currently this is only possible by
loading the driver with mtu_max=7912 but this also forces
a smaller block ACK window size which reduces performance
for stations which transmit normal sized packets (<2KB).
Fix this problem as follows:
1. Add a module parameter rx_large_buf that when set,
will allocate 8KB RX buffers regardless of mtu_max
setting.
2. When receiving block ACK request agree to any window
size not above our maximum, regardless of the mtu_max setting.
This means if the other side transmits small packets (2KB)
it can still set up block ACK with a large window size,
and get better performance.
Signed-off-by: Lior David <qca_liord@qca.qualcomm.com>
Signed-off-by: Maya Erez <qca_merez@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
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The power save profile is set to default state in case of FW reset,
regardless of the state before the reset took place.
Fix this by saving the current power save profile and restore it
in case of FW reset.
Signed-off-by: Lazar Alexei <qca_ailizaro@qca.qualcomm.com>
Signed-off-by: Maya Erez <qca_merez@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
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Communication with FW must be done before wil->status
is initialized in order to properly handle cases where
communication with FW halts during reset sequence.
Signed-off-by: Hamad Kadmany <qca_hkadmany@qca.qualcomm.com>
Signed-off-by: Maya Erez <qca_merez@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
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In 'ath10k_ce_alloc_pipe' the compile time sanity check to
ensure that there is sufficient buffers in CE4 for HTT Tx
MSDU descriptors, but this did not take into account of the
case with 'peer flow control' enabled, fix this.
Cc: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qti.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
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Fix fallout too.
Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Steve deRosier <derosier@gmail.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
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There are two bugs in the follow-MAC code:
* it treats the radiotap header as the 802.11 header
(therefore it can't possibly work)
* it doesn't verify that the skb data it accesses is actually
present in the header, which is mitigated by the first point
Fix this by moving all of this out into a separate function.
This function copies the data it needs using skb_copy_bits()
to make sure it can be accessed if it's paged, and offsets
that by the possibly present vendor radiotap header.
This also makes all those conditions more readable.
Cc: stable@vger.kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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Interrupt numbers are never negative, zero serves as the special invalid
value.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
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The snd_use_lock_sync() (thus its implementation
snd_use_lock_sync_helper()) has the 5 seconds timeout to break out of
the sync loop. It was introduced from the beginning, just to be
"safer", in terms of avoiding the stupid bugs.
However, as Ben Hutchings suggested, this timeout rather introduces a
potential leak or use-after-free that was apparently fixed by the
commit 2d7d54002e39 ("ALSA: seq: Fix race during FIFO resize"):
for example, snd_seq_fifo_event_in() -> snd_seq_event_dup() ->
copy_from_user() could block for a long time, and snd_use_lock_sync()
goes timeout and still leaves the cell at releasing the pool.
For fixing such a problem, we remove the break by the timeout while
still keeping the warning.
Suggested-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
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When channel contexts are used, there's no global power level
(the power_level is always 0). Use the per-interface TX power
in mac80211_hwsim to have a proper setting for both cases.
This fixes the bgscan_simple and bgscan_learn test cases when
the number of channels advertised by hwsim is >1 by default.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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Refactor the code to have common code for changing monitor
options when adding and changing virtual interfaces. This
will make it easier to add BPF filters to both paths. Note
that this code carefully checks the error conditions first
and only then applies the changes, to guarantee atomicity.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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Refactor the parsing of monitor flags and the MU-MIMO options.
This will allow adding more things cleanly in the future and
also allows setting the latter already when creating a monitor
interface.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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Instead passing both flags, which can be NULL, and vif_params,
which are never NULL, move the flags into the vif_params and
use BIT(0), which is invalid from userspace, to indicate that
the flags were changed.
While updating all drivers, fix a small bug in wil6210 where
it was setting the flags to 0 instead of leaving them unchanged.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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The MU-MIMO monitor follow functionality is broken because it
doesn't clear the MU-MIMO owner even if both follow features
are disabled. Fix that, and while at it move the code into a
new helper function. Call this also when creating a new monitor
interface to prepare for an upcoming cfg80211 change allowing
that.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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When changing monitor parameters, not setting the MU-MIMO attributes
should mean that they're not changed - it's documented that to turn
the feature off it's necessary to set all-zero group membership and
an invalid follow-address. This isn't implemented.
Fix this by making the parameters pointers, stop reusing the macaddr
struct member, and documenting that NULL pointers mean unchanged.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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Instead of dropping such frames only when removing the
monitor info, drop them earlier (keeping the warning)
and simplify removing monitor info. While at it, make
that function return void.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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On stih407-410 chip family the GDP layers are able to support up to UHD
resolution (3840 x 2160).
Signed-off-by: Vincent Abriou <vincent.abriou@st.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Tested-by: Lee Jones <lee.jones@linaro.org>
Link: http://patchwork.freedesktop.org/patch/msgid/1490280292-30466-1-git-send-email-vincent.abriou@st.com
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This patch utilizes the new PLL clk notifier to gate then ungate the
PLL CPU clock after rate changes. This should mitigate the system
hangs observed after the introduction of cpufreq for the A33.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Tested-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
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In common PLL designs, changes to the dividers take effect almost
immediately, while changes to the multipliers (implemented as
dividers in the feedback loop) take a few cycles to work into
the feedback loop for the PLL to stablize.
Sometimes when the PLL clock rate is changed, the decrease in the
divider is too much for the decrease in the multiplier to catch up.
The PLL clock rate will spike, and in some cases, might lock up
completely. This is especially the case if the divider changed is
the pre-divider, which affects the reference frequency.
This patch introduces a clk notifier callback that will gate and
then ungate a clk after a rate change, effectively resetting it,
so it continues to work, despite any possible lockups. Care must
be taken to reparent any consumers to other temporary clocks during
the rate change, and that this notifier callback must be the first
to be registered.
This is intended to fix occasional lockups with cpufreq on newer
Allwinner SoCs, such as the A33 and the H3. Previously it was
thought that reparenting the cpu clock away from the PLL while
it stabilized was enough, as this worked quite well on the A31.
On the A33, hangs have been observed after cpufreq was recently
introduced. With the H3, a more thorough test [1] showed that
reparenting alone isn't enough. The system still locks up unless
the dividers are limited to 1.
A hunch was if the PLL was stuck in some unknown state, perhaps
gating then ungating it would bring it back to normal. Tests
done by Icenowy Zheng using Ondrej's test firmware shows this
to be a valid solution.
[1] http://www.spinics.net/lists/arm-kernel/msg552501.html
Reported-by: Ondrej Jirman <megous@megous.com>
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Tested-by: Icenowy Zheng <icenowy@aosc.io>
Tested-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
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