Commit Graph

2260 Commits

Author SHA1 Message Date
Shilpasri G Bhat
20b0f757da cpufreq: powernv: Fix hardlockup due to synchronous smp_call in timer interrupt
commit c0f7f5b6c6 upstream.

gpstate_timer_handler() uses synchronous smp_call to set the pstate
on the requested core. This causes the below hard lockup:

  smp_call_function_single+0x110/0x180 (unreliable)
  smp_call_function_any+0x180/0x250
  gpstate_timer_handler+0x1e8/0x580
  call_timer_fn+0x50/0x1c0
  expire_timers+0x138/0x1f0
  run_timer_softirq+0x1e8/0x270
  __do_softirq+0x158/0x3e4
  irq_exit+0xe8/0x120
  timer_interrupt+0x9c/0xe0
  decrementer_common+0x114/0x120
  -- interrupt: 901 at doorbell_global_ipi+0x34/0x50
  LR = arch_send_call_function_ipi_mask+0x120/0x130
  arch_send_call_function_ipi_mask+0x4c/0x130
  smp_call_function_many+0x340/0x450
  pmdp_invalidate+0x98/0xe0
  change_huge_pmd+0xe0/0x270
  change_protection_range+0xb88/0xe40
  mprotect_fixup+0x140/0x340
  SyS_mprotect+0x1b4/0x350
  system_call+0x58/0x6c

One way to avoid this is removing the smp-call. We can ensure that the
timer always runs on one of the policy-cpus. If the timer gets
migrated to a cpu outside the policy then re-queue it back on the
policy->cpus. This way we can get rid of the smp-call which was being
used to set the pstate on the policy->cpus.

Fixes: 7bc54b652f ("timers, cpufreq/powernv: Initialize the gpstate timer as pinned")
Cc: stable@vger.kernel.org # v4.8+
Reported-by: Nicholas Piggin <npiggin@gmail.com>
Reported-by: Pridhiviraj Paidipeddi <ppaidipe@linux.vnet.ibm.com>
Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
Acked-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-01 12:58:24 -07:00
Chen Yu
ae9c78af57 cpufreq: intel_pstate: Enable HWP during system resume on CPU0
[ Upstream commit 70f6bf2a3b ]

When maxcpus=1 is in the kernel command line, the BP is responsible
for re-enabling the HWP - because currently only the APs invoke
intel_pstate_hwp_enable() during their online process - which might
put the system into unstable state after resume.

Fix this by enabling the HWP explicitly on BP during resume.

Reported-by: Doug Smythies <dsmythies@telus.net>
Suggested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Yu Chen <yu.c.chen@intel.com>
[ rjw: Subject/changelog, minor modifications ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-26 11:02:18 +02:00
George Cherian
f1e90bf95e cpufreq: CPPC: Use transition_delay_us depending transition_latency
commit 3d41386d55 upstream.

With commit e948bc8fbe (cpufreq: Cap the default transition delay
value to 10 ms)  the cpufreq was not honouring the delay passed via
ACPI (PCCT). Due to which on ARM based platforms using CPPC the
cpufreq governor tries to change the frequency of CPUs faster than
expected.

This leads to continuous error messages like the following.
" ACPI CPPC: PCC check channel failed. Status=0 "

Earlier (without above commit) the default transition delay was
taken form the value passed from PCCT. Use the same value provided
by PCCT to set the transition_delay_us.

Fixes: e948bc8fbe (cpufreq: Cap the default transition delay value to 10 ms)
Signed-off-by: George Cherian <george.cherian@cavium.com>
Cc: 4.14+ <stable@vger.kernel.org> # 4.14+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-24 09:36:21 +02:00
Gautham R. Shenoy
da5e12ab59 powernv-cpufreq: Add helper to extract pstate from PMSR
[ Upstream commit ee1f4a7daf ]

On POWERNV platform, the fields for pstates in the Power Management
Status Register (PMSR) and the Power Management Control Register
(PMCR) are 8-bits wide. On POWER8 the pstates are negatively numbered
while on POWER9 they are positively numbered.

The device-tree exports pstates as 32-bit entries. The device-tree
implementation sign-extends the 8-bit pstate values to obtain the
corresponding 32-bit entry.

Eg: On POWER8, a pstate value 0x82 [-126] is represented in the
device-tree as 0xfffffff82 while on POWER9, the same value 0x82 [130]
is represented in the device-tree as 0x00000082.

The powernv-cpufreq driver implementation represents pstates using the
integer type. In multiple places in the driver, the code interprets
the pstates extracted from the PMSR as a signed byte and assigns it to
a integer variable to get the sign-extention.

On POWER9 platforms which have greater than 128 pstates, this results
in the driver performing incorrect sign-extention, and thereby
treating a legitimate pstate (say 130) as an invalid pstates (since it
is interpreted as -126).

This patch fixes the issue by implementing a helper function to
extract Pstates from PMSR register, and correctly sign-extend it to be
consistent with the values provided by the device-tree.

Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-12 12:32:15 +02:00
Greg Kroah-Hartman
cfbed9b556 Revert "cpufreq: Fix governor module removal race"
This reverts commit 0049457bfd which was
commit a8b149d32b upstream.

The backport was not correct, so just drop it entirely.

Reported-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-08 14:26:34 +02:00
Viresh Kumar
b453f9d8c5 cpufreq: longhaul: Revert transition_delay_us to 200 ms
[ Upstream commit 1d0d064307 ]

The commit e948bc8fbe ("cpufreq: Cap the default transition delay
value to 10 ms") caused a regression on EPIA-M min-ITX computer where
shutdown or reboot hangs occasionally with a print message like:

longhaul: Warning: Timeout while waiting for idle PCI bus
cpufreq: __target_index: Failed to change cpu frequency: -16

This probably happens because the cpufreq governor tries to change the
frequency of the CPU faster than allowed by the hardware.

Before the above commit, the default transition delay was set to 200 ms
for a transition_latency of 200000 ns. Lets revert back to that
transition delay value to fix it. Note that several other transition
delay values were tested like 20 ms and 30 ms and none of them have
resolved system hang issue completely.

Fixes: e948bc8fbe (cpufreq: Cap the default transition delay value to 10 ms)
Reported-by: Meelis Roos <mroos@linux.ee>
Suggested-by: Rafael J. Wysocki <rjw@rjwysocki.net>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-24 11:01:21 +01:00
Rafael J. Wysocki
0049457bfd cpufreq: Fix governor module removal race
[ Upstream commit a8b149d32b ]

It is possible to remove a cpufreq governor module after
cpufreq_parse_governor() has returned success in
store_scaling_governor() and before cpufreq_set_policy()
acquires a reference to it, because the governor list is
not protected during that period and nothing prevents the
governor from being unregistered then.

Prevent that from happening by acquiring an extra reference
to the governor module temporarily in cpufreq_parse_governor(),
under cpufreq_governor_mutex, and dropping it in
store_scaling_governor(), when cpufreq_set_policy() returns.

Note that the second cpufreq_parse_governor() call site is fine,
because it only cares about the policy member of new_policy.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-19 08:42:51 +01:00
Viresh Kumar
3379a37a74 cpufreq: s3c24xx: Fix broken s3c_cpufreq_init()
commit 0373ca7483 upstream.

commit a307a1e6bc "cpufreq: s3c: use cpufreq_generic_init()"
accidentally broke cpufreq on s3c2410 and s3c2412.

These two platforms don't have a CPU frequency table and used to skip
calling cpufreq_table_validate_and_show() for them.  But with the
above commit, we started calling it unconditionally and that will
eventually fail as the frequency table pointer is NULL.

Fix this by calling cpufreq_table_validate_and_show() conditionally
again.

Fixes: a307a1e6bc "cpufreq: s3c: use cpufreq_generic_init()"
Cc: 3.13+ <stable@vger.kernel.org> # v3.13+
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08 22:41:06 -08:00
Jia Zhang
325cbb04dc x86/cpu: Rename cpu_data.x86_mask to cpu_data.x86_stepping
commit b399151cb4 upstream.

x86_mask is a confusing name which is hard to associate with the
processor's stepping.

Additionally, correct an indent issue in lib/cpu.c.

Signed-off-by: Jia Zhang <qianyue.zj@alibaba-inc.com>
[ Updated it to more recent kernels. ]
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bp@alien8.de
Cc: tony.luck@intel.com
Link: http://lkml.kernel.org/r/1514771530-70829-1-git-send-email-qianyue.zj@alibaba-inc.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-22 15:42:24 +01:00
Shilpasri G Bhat
8e56a935a4 cpufreq: powernv: Dont assume distinct pstate values for nominal and pmin
commit 3fa4680b86 upstream.

Some OpenPOWER boxes can have same pstate values for nominal and
pmin pstates. In these boxes the current code will not initialize
'powernv_pstate_info.min' variable and result in erroneous CPU
frequency reporting. This patch fixes this problem.

Fixes: 09ca4c9b59 (cpufreq: powernv: Replacing pstate_id with frequency table index)
Reported-by: Alvin Wang <wangat@tw.ibm.com>
Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 4.8+ <stable@vger.kernel.org> # 4.8+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-22 15:42:15 +01:00
Andrew-sh Cheng
7adf1d63ef cpufreq: mediatek: add mediatek related projects into blacklist
commit 6066998cbd upstream.

mediatek projects will use mediate-cpufreq.c as cpufreq driver,
instead of using cpufreq_dt.c
Add mediatek related projects into cpufreq-dt blacklist

Signed-off-by: Andrew-sh Cheng <andrew-sh.cheng@mediatek.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-16 20:22:43 +01:00
James Hogan
d290178f00 cpufreq: Add Loongson machine dependencies
[ Upstream commit 0d307935fe ]

The MIPS loongson cpufreq drivers don't build unless configured for the
correct machine type, due to dependency on machine specific architecture
headers and symbols in machine specific platform code.

More specifically loongson1-cpufreq.c uses RST_CPU_EN and RST_CPU,
neither of which is defined in asm/mach-loongson32/regs-clk.h unless
CONFIG_LOONGSON1_LS1B=y, and loongson2_cpufreq.c references
loongson2_clockmod_table[], which is only defined in
arch/mips/loongson64/lemote-2f/clock.c, i.e. when
CONFIG_LEMOTE_MACH2F=y.

Add these dependencies to Kconfig to avoid randconfig / allyesconfig
build failures (e.g. when based on BMIPS which also has a cpufreq
driver).

Signed-off-by: James Hogan <jhogan@kernel.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-03 17:39:00 +01:00
Rafael J. Wysocki
c83189edf4 cpufreq: governor: Ensure sufficiently large sampling intervals
commit 56026645e2 upstream.

After commit aa7519af45 (cpufreq: Use transition_delay_us for legacy
governors as well) the sampling_rate field of struct dbs_data may be
less than the tick period which causes dbs_update() to produce
incorrect results, so make the code ensure that the value of that
field will always be sufficiently large.

Fixes: aa7519af45 (cpufreq: Use transition_delay_us for legacy governors as well)
Reported-by: Andy Tang <andy.tang@nxp.com>
Reported-by: Doug Smythies <dsmythies@telus.net>
Tested-by: Andy Tang <andy.tang@nxp.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-31 14:03:50 +01:00
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Suniel Mahesh
d477bf3af1 cpufreq: dt: Fix sysfs duplicate filename creation for platform-device
ti-cpufreq and cpufreq-dt-platdev drivers are registering platform-device
with same name "cpufreq-dt" using platform_device_register_*() routines.
This is leading to build warnings appended below.

Providing hardware information to OPP framework along with the platform-
device creation should be done by ti-cpufreq driver before cpufreq-dt
driver comes into place.

This patch add's TI am33xx, am43 and dra7 platforms (which use opp-v2
property) to the blacklist of devices in cpufreq-dt-platform driver to
avoid creating platform-device twice and remove build warnings.

[    2.370167] ------------[ cut here ]------------
[    2.375087] WARNING: CPU: 0 PID: 1 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x58/0x78
[    2.383112] sysfs: cannot create duplicate filename '/devices/platform/cpufreq-dt'
[    2.391219] Modules linked in:
[    2.394506] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.13.0-next-20170912 #1
[    2.402006] Hardware name: Generic AM33XX (Flattened Device Tree)
[    2.408437] [<c0110a28>] (unwind_backtrace) from [<c010ca84>] (show_stack+0x10/0x14)
[    2.416568] [<c010ca84>] (show_stack) from [<c0827d64>] (dump_stack+0xac/0xe0)
[    2.424165] [<c0827d64>] (dump_stack) from [<c0137470>] (__warn+0xd8/0x104)
[    2.431488] [<c0137470>] (__warn) from [<c01374d0>] (warn_slowpath_fmt+0x34/0x44)
[    2.439351] [<c01374d0>] (warn_slowpath_fmt) from [<c03459d0>] (sysfs_warn_dup+0x58/0x78)
[    2.447938] [<c03459d0>] (sysfs_warn_dup) from [<c0345ab8>] (sysfs_create_dir_ns+0x80/0x98)
[    2.456719] [<c0345ab8>] (sysfs_create_dir_ns) from [<c082c554>] (kobject_add_internal+0x9c/0x2d4)
[    2.466124] [<c082c554>] (kobject_add_internal) from [<c082c7d8>] (kobject_add+0x4c/0x9c)
[    2.474712] [<c082c7d8>] (kobject_add) from [<c05803e4>] (device_add+0xcc/0x57c)
[    2.482489] [<c05803e4>] (device_add) from [<c0584b74>] (platform_device_add+0x100/0x220)
[    2.491085] [<c0584b74>] (platform_device_add) from [<c05855a8>] (platform_device_register_full+0xf4/0x118)
[    2.501305] [<c05855a8>] (platform_device_register_full) from [<c067023c>] (ti_cpufreq_init+0x150/0x22c)
[    2.511253] [<c067023c>] (ti_cpufreq_init) from [<c0101df4>] (do_one_initcall+0x3c/0x170)
[    2.519838] [<c0101df4>] (do_one_initcall) from [<c0c00eb4>] (kernel_init_freeable+0x1fc/0x2c4)
[    2.528974] [<c0c00eb4>] (kernel_init_freeable) from [<c083bcac>] (kernel_init+0x8/0x110)
[    2.537565] [<c083bcac>] (kernel_init) from [<c0107d18>] (ret_from_fork+0x14/0x3c)
[    2.545981] ---[ end trace 2fc00e213c13ab20 ]---
[    2.551051] ------------[ cut here ]------------
[    2.555931] WARNING: CPU: 0 PID: 1 at lib/kobject.c:240 kobject_add_internal+0x254/0x2d4
[    2.564578] kobject_add_internal failed for cpufreq-dt with -EEXIST, don't try to register
things with the same name in the same directory.
[    2.577977] Modules linked in:
[    2.581261] CPU: 0 PID: 1 Comm: swapper/0 Tainted: G        W       4.13.0-next-20170912 #1
[    2.590013] Hardware name: Generic AM33XX (Flattened Device Tree)
[    2.596437] [<c0110a28>] (unwind_backtrace) from [<c010ca84>] (show_stack+0x10/0x14)
[    2.604573] [<c010ca84>] (show_stack) from [<c0827d64>] (dump_stack+0xac/0xe0)
[    2.612172] [<c0827d64>] (dump_stack) from [<c0137470>] (__warn+0xd8/0x104)
[    2.619494] [<c0137470>] (__warn) from [<c01374d0>] (warn_slowpath_fmt+0x34/0x44)
[    2.627362] [<c01374d0>] (warn_slowpath_fmt) from [<c082c70c>] (kobject_add_internal+0x254/0x2d4)
[    2.636666] [<c082c70c>] (kobject_add_internal) from [<c082c7d8>] (kobject_add+0x4c/0x9c)
[    2.645255] [<c082c7d8>] (kobject_add) from [<c05803e4>] (device_add+0xcc/0x57c)
[    2.653027] [<c05803e4>] (device_add) from [<c0584b74>] (platform_device_add+0x100/0x220)
[    2.661615] [<c0584b74>] (platform_device_add) from [<c05855a8>] (platform_device_register_full+0xf4/0x118)
[    2.671833] [<c05855a8>] (platform_device_register_full) from [<c067023c>] (ti_cpufreq_init+0x150/0x22c)
[    2.681779] [<c067023c>] (ti_cpufreq_init) from [<c0101df4>] (do_one_initcall+0x3c/0x170)
[    2.690377] [<c0101df4>] (do_one_initcall) from [<c0c00eb4>] (kernel_init_freeable+0x1fc/0x2c4)
[    2.699510] [<c0c00eb4>] (kernel_init_freeable) from [<c083bcac>] (kernel_init+0x8/0x110)
[    2.708106] [<c083bcac>] (kernel_init) from [<c0107d18>] (ret_from_fork+0x14/0x3c)
[    2.716217] ---[ end trace 2fc00e213c13ab21 ]---

Fixes: edeec420de (cpufreq: dt-cpufreq: platdev Automatically create device with OPP v2)
Signed-off-by: Suniel Mahesh <sunil.m@techveda.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-09-26 01:10:08 +02:00
Dave Gerlach
039cc1c1eb cpufreq: ti-cpufreq: Support additional am43xx platforms
Rather than letting the ti-cpufreq driver match against 'ti,am4372'
machine compatible during probe let's match against 'ti,am43' so that we
can support both 'ti,am4372' and 'ti,am438x' platforms which both match
to this compatible.

Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-09-20 00:51:01 +02:00
Viresh Kumar
ff76898c0a cpufreq: dt-platdev: Add some missing platforms to the blacklist
Commit edeec420de (cpufreq: dt-platdev: Automatically create cpufreq
device with OPP v2) missed adding few platforms to the blacklist which
create the cpufreq-dt device from their own drivers, after some
dependencies are sorted out.

And for those platforms, both the platform specific driver and the
cpufreq-dt-platdev driver try to create the cpufreq-dt device now.

Fix that by including those platforms in the blacklist. This doesn't include
the TI platforms, for which there is a separate patch.

Fixes: edeec420de (cpufreq: dt-cpufreq: platdev Automatically create device with OPP v2)
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-09-19 23:05:28 +02:00
Christoph Hellwig
6faadbbb7f dmi: Mark all struct dmi_system_id instances const
... and __initconst if applicable.

Based on similar work for an older kernel in the Grsecurity patch.

[JD: fix toshiba-wmi build]
[JD: add htcpen]
[JD: move __initconst where checkscript wants it]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jean Delvare <jdelvare@suse.de>
2017-09-14 11:59:30 +02:00
Linus Torvalds
53ac64aac9 Merge tag 'acpi-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI updates from Rafael Wysocki:
 "These include a usual ACPICA code update (this time to upstream
  revision 20170728), a fix for a boot crash on some systems with
  Thunderbolt devices connected at boot time, a rework of the handling
  of PCI bridges when setting up device wakeup, new support for Apple
  device properties, support for DMA configurations reported via ACPI on
  ARM64, APEI-related updates, ACPI EC driver updates and assorted minor
  modifications in several places.

  Specifics:

   - Update the ACPICA code in the kernel to upstream revision 20170728
     including:
      * Alias operator handling update (Bob Moore).
      * Deferred resolution of reference package elements (Bob Moore).
      * Support for the _DMA method in walk resources (Bob Moore).
      * Tables handling update and support for deferred table
        verification (Lv Zheng).
      * Update of SMMU models for IORT (Robin Murphy).
      * Compiler and disassembler updates (Alex James, Erik Schmauss,
        Ganapatrao Kulkarni, James Morse).
      * Tools updates (Erik Schmauss, Lv Zheng).
      * Assorted minor fixes and cleanups (Bob Moore, Kees Cook, Lv
        Zheng, Shao Ming).

   - Rework the initialization of non-wakeup GPEs with method handlers
     in order to address a boot crash on some systems with Thunderbolt
     devices connected at boot time where we miss an early hotplug event
     due to a delay in GPE enabling (Rafael Wysocki).

   - Rework the handling of PCI bridges when setting up ACPI-based
     device wakeup in order to avoid disabling wakeup for bridges
     prematurely (Rafael Wysocki).

   - Consolidate Apple DMI checks throughout the tree, add support for
     Apple device properties to the device properties framework and use
     these properties for the handling of I2C and SPI devices on Apple
     systems (Lukas Wunner).

   - Add support for _DMA to the ACPI-based device properties lookup
     code and make it possible to use the information from there to
     configure DMA regions on ARM64 systems (Lorenzo Pieralisi).

   - Fix several issues in the APEI code, add support for exporting the
     BERT error region over sysfs and update APEI MAINTAINERS entry with
     reviewers information (Borislav Petkov, Dongjiu Geng, Loc Ho, Punit
     Agrawal, Tony Luck, Yazen Ghannam).

   - Fix a potential initialization ordering issue in the ACPI EC driver
     and clean it up somewhat (Lv Zheng).

   - Update the ACPI SPCR driver to extend the existing XGENE 8250
     workaround in it to a new platform (m400) and to work around an
     Xgene UART clock issue (Graeme Gregory).

   - Add a new utility function to the ACPI core to support using ACPI
     OEM ID / OEM Table ID / Revision for system identification in
     blacklisting or similar and switch over the existing code already
     using this information to this new interface (Toshi Kani).

   - Fix an xpower PMIC issue related to GPADC reads that always return
     0 without extra pin manipulations (Hans de Goede).

   - Add statements to print debug messages in a couple of places in the
     ACPI core for easier diagnostics (Rafael Wysocki).

   - Clean up the ACPI processor driver slightly (Colin Ian King, Hanjun
     Guo).

   - Clean up the ACPI x86 boot code somewhat (Andy Shevchenko).

   - Add a quirk for Dell OptiPlex 9020M to the ACPI backlight driver
     (Alex Hung).

   - Assorted fixes, cleanups and updates related to ACPI (Amitoj Kaur
     Chawla, Bhumika Goyal, Frank Rowand, Jean Delvare, Punit Agrawal,
     Ronald Tschalär, Sumeet Pawnikar)"

* tag 'acpi-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (75 commits)
  ACPI / APEI: Suppress message if HEST not present
  intel_pstate: convert to use acpi_match_platform_list()
  ACPI / blacklist: add acpi_match_platform_list()
  ACPI, APEI, EINJ: Subtract any matching Register Region from Trigger resources
  ACPI: make device_attribute const
  ACPI / sysfs: Extend ACPI sysfs to provide access to boot error region
  ACPI: APEI: fix the wrong iteration of generic error status block
  ACPI / processor: make function acpi_processor_check_duplicates() static
  ACPI / EC: Clean up EC GPE mask flag
  ACPI: EC: Fix possible issues related to EC initialization order
  ACPI / PM: Add debug statements to acpi_pm_notify_handler()
  ACPI: Add debug statements to acpi_global_event_handler()
  ACPI / scan: Enable GPEs before scanning the namespace
  ACPICA: Make it possible to enable runtime GPEs earlier
  ACPICA: Dispatch active GPEs at init time
  ACPI: SPCR: work around clock issue on xgene UART
  ACPI: SPCR: extend XGENE 8250 workaround to m400
  ACPI / LPSS: Don't abort ACPI scan on missing mem resource
  mailbox: pcc: Drop uninformative output during boot
  ACPI/IORT: Add IORT named component memory address limits
  ...
2017-09-05 12:45:03 -07:00
Rafael J. Wysocki
ab271bc95b Merge branch 'intel_pstate'
* intel_pstate:
  cpufreq: intel_pstate: Shorten a couple of long names
  cpufreq: intel_pstate: Simplify intel_pstate_adjust_pstate()
  cpufreq: intel_pstate: Improve IO performance with per-core P-states
  cpufreq: intel_pstate: Drop INTEL_PSTATE_HWP_SAMPLING_INTERVAL
  cpufreq: intel_pstate: Drop ->update_util from pstate_funcs
  cpufreq: intel_pstate: Do not use PID-based P-state selection
2017-09-04 00:05:42 +02:00
Rafael J. Wysocki
08a10002be Merge branch 'pm-cpufreq-sched'
* pm-cpufreq-sched:
  cpufreq: schedutil: Always process remote callback with slow switching
  cpufreq: schedutil: Don't restrict kthread to related_cpus unnecessarily
  cpufreq: Return 0 from ->fast_switch() on errors
  cpufreq: Simplify cpufreq_can_do_remote_dvfs()
  cpufreq: Process remote callbacks from any CPU if the platform permits
  sched: cpufreq: Allow remote cpufreq callbacks
  cpufreq: schedutil: Use unsigned int for iowait boost
  cpufreq: schedutil: Make iowait boost more energy efficient
2017-09-04 00:05:22 +02:00
Rafael J. Wysocki
bd87c8fb9d Merge branch 'pm-cpufreq'
* pm-cpufreq: (33 commits)
  cpufreq: imx6q: Fix imx6sx low frequency support
  cpufreq: speedstep-lib: make several arrays static, makes code smaller
  cpufreq: ti: Fix 'of_node_put' being called twice in error handling path
  cpufreq: dt-platdev: Drop few entries from whitelist
  cpufreq: dt-platdev: Automatically create cpufreq device with OPP v2
  ARM: ux500: don't select CPUFREQ_DT
  cpufreq: Convert to using %pOF instead of full_name
  cpufreq: Cap the default transition delay value to 10 ms
  cpufreq: dbx500: Delete obsolete driver
  mfd: db8500-prcmu: Get rid of cpufreq dependency
  cpufreq: enable the DT cpufreq driver on the Ux500
  cpufreq: Loongson2: constify platform_device_id
  cpufreq: dt: Add r8a7796 support to to use generic cpufreq driver
  cpufreq: remove setting of policy->cpu in policy->cpus during init
  cpufreq: mediatek: add support of cpufreq to MT7622 SoC
  cpufreq: mediatek: add cleanups with the more generic naming
  cpufreq: rcar: Add support for R8A7795 SoC
  cpufreq: dt: Add rk3328 compatible to use generic cpufreq driver
  cpufreq: s5pv210: add missing of_node_put()
  cpufreq: Allow dynamic switching with CPUFREQ_ETERNAL latency
  ...
2017-09-04 00:05:13 +02:00
Toshi Kani
5e93232194 intel_pstate: convert to use acpi_match_platform_list()
Convert to use acpi_match_platform_list() for the platform check.
There is no change in functionality.

Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-29 01:42:49 +02:00
Leonard Crestez
fded5fc841 cpufreq: imx6q: Fix imx6sx low frequency support
This patch contains the minimal changes required to support imx6sx OPP
of 198 Mhz. Without this patch cpufreq still reports success but the
frequency is not changed, the "arm" clock will still be at 396000000 in
clk_summary.

In order to do this PLL1 needs to be still kept enabled while changing
the ARM clock. This is a hardware requirement: when ARM_PODF is changed
in CCM we need to check the busy bit of CCM_CDHIPR bit 16 arm_podf_busy,
and this bit is sync with PLL1 clock, so if PLL1 NOT enabled, this
bit will never get clear.

Keep pll1_sys explicitly enabled until after the rate is change to deal
with this. Otherwise from the clk framework perspective pll1_sys is
unused and gets turned off.

Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-29 00:22:52 +02:00
Colin Ian King
843791bb6c cpufreq: speedstep-lib: make several arrays static, makes code smaller
Don't populate arrays on the stack, instead make them static.
Makes the object code smaller by over 860 bytes:

Before:
   text	   data	    bss	    dec	    hex	filename
  10716	   5196	      0	  15912	   3e28	drivers/cpufreq/speedstep-lib.o

After:
   text	   data	    bss	    dec	    hex	filename
   9690	   5356	      0	  15046	   3ac6	drivers/cpufreq/speedstep-lib.o

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-29 00:21:41 +02:00
Christophe Jaillet
9a6e91d08e cpufreq: ti: Fix 'of_node_put' being called twice in error handling path
If 'dev_pm_opp_set_supported_hw()' fails, 'opp_data->opp_node' refcount
will be decremented 2 times.
One, just a few lines above, and another one in the error handling path.

Fix it by simply moving the 'of_node_put' call of the normal path.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-25 01:43:07 +02:00
Viresh Kumar
d79d148b64 cpufreq: dt-platdev: Drop few entries from whitelist
Drop few ARM (32 and 64 bit) platforms from the whitelist which always
use "operating-points-v2" property from their DT. They should continue
to work after this patch.

Tested on Hikey platform (only the "hisilicon,hi6220" entry).

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-25 01:41:03 +02:00
Viresh Kumar
edeec420de cpufreq: dt-platdev: Automatically create cpufreq device with OPP v2
The initial idea of creating the cpufreq-dt-platdev.c file was to keep a
list of platforms that use the "operating-points" (V1) bindings and
create cpufreq device for them only, as we weren't sure which platforms
would want the device to get created automatically as some had their own
cpufreq drivers as well, or wanted to initialize cpufreq after doing
some stuff from platform code.

But that wasn't the case with platforms using "operating-points-v2"
property. We wanted the device to get created automatically without the
need of adding them to the whitelist. Though, we will still have some
exceptions where we don't want to create the device automatically.

Rename the earlier platform list as *whitelist* and create a new
*blacklist* as well.

The cpufreq-dt device will get created if:
- The platform is there in the whitelist OR
- The platform has "operating-points-v2" property in CPU0's DT node and
  isn't part of the blacklist .

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-25 01:41:03 +02:00
Rob Herring
cc5a7a7494 cpufreq: Convert to using %pOF instead of full_name
Now that we have a custom printf format specifier, convert users of
full_name to use %pOF instead. This is preparation to remove storing
of the full path string for each node.

Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Patrice Chotard <patrice.chotard@st.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-25 01:20:46 +02:00
Viresh Kumar
e948bc8fbe cpufreq: Cap the default transition delay value to 10 ms
If transition_delay_us isn't defined by the cpufreq driver, the default
value of transition delay (time after which the cpufreq governor will
try updating the frequency again) is currently calculated by multiplying
transition_latency (nsec) with LATENCY_MULTIPLIER (1000) and then
converting this time to usec. That gives the exact same value as
transition_latency, just that the time unit is usec instead of nsec.

With acpi-cpufreq for example, transition_latency is set to around 10
usec and we get transition delay as 10 ms. Which seems to be a
reasonable amount of time to reevaluate the frequency again.

But for platforms where frequency switching isn't that fast (like ARM),
the transition_latency varies from 500 usec to 3 ms, and the transition
delay becomes 500 ms to 3 seconds. Of course, that is a pretty bad
default value to start with.

We can try to come across a better formula (instead of multiplying with
LATENCY_MULTIPLIER) to solve this problem, but will that be worth it ?

This patch tries a simple approach and caps the maximum value of default
transition delay to 10 ms. Of course, userspace can still come in and
change this value anytime or individual drivers can rather provide
transition_delay_us instead.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-22 15:50:03 +02:00
Linus Walleij
919096f7f3 cpufreq: dbx500: Delete obsolete driver
We have moved the Ux500 over to use the generic DT based
cpufreq driver, so delete the old custom driver.

At the same time select CPUFREQ_DT from the machine's
Kconfig in order to satisfy the "default ARCH_U8500"
selection on the old driver.

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-22 15:50:02 +02:00
Rafael J. Wysocki
57ccaf3384 Merge back intel_pstate material for v4.14. 2017-08-21 01:50:20 +02:00
Linus Walleij
ff6c349f74 cpufreq: enable the DT cpufreq driver on the Ux500
This enables the generic DT and OPP-based cpufreq driver on the
ST-Ericsson Ux500 series.

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-18 01:46:40 +02:00
Arvind Yadav
a804d51004 cpufreq: Loongson2: constify platform_device_id
platform_device_id are not supposed to change at runtime. All functions
working with platform_device_id provided by <linux/platform_device.h>
work with const platform_device_id. So mark the non-const structs as
const.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-18 01:44:21 +02:00
Khiem Nguyen
bea2ebca6b cpufreq: dt: Add r8a7796 support to to use generic cpufreq driver
This patch adds the r8a7796 support the generic cpufreq driver
by adding an appropriate compat string. This is in keeping
with support for other Renesas ARM and arm64 based SoCs.

Signed-off-by: Khiem Nguyen <khiem.nguyen.xt@rvc.renesas.com>
[simon: new changelog]
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-18 01:42:46 +02:00
Sudeep Holla
b20a3f3d8a cpufreq: remove setting of policy->cpu in policy->cpus during init
policy->cpu is copied into policy->cpus in cpufreq_online() before
calling into cpufreq_driver->init(). So there's no need to set the
same in the individual driver init() functions again.

This patch removes the redundant setting of policy->cpu in policy->cpus
in intel_pstate and cppc drivers.

Reported-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-18 01:41:37 +02:00
Doug Smythies
c587c79f90 cpufreq: intel_pstate: report correct CPU frequencies during trace
The intel_pstate CPU frequency scaling driver has always
calculated CPU frequency incorrectly.  Recent changes have
eliminted most of the issues, however the frequency reported
in the trace buffer, if used, is incorrect.

It remains desireable that cpu->pstate.scaling still be a nice
round number for things such as when setting max and min frequencies.
So the proposal is to just fix the reported frequency in the trace data.

Fixes what remains of [1].

Link: https://bugzilla.kernel.org/show_bug.cgi?id=96521 # [1]
Signed-off-by: Doug Smythies <dsmythies@telus.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-11 01:25:53 +02:00
Sean Wang
ccc03d86e2 cpufreq: mediatek: add support of cpufreq to MT7622 SoC
MT7622 is a 64-bit ARMv8 based dual-core SoC (2 * Cortex-A53) with a
single cluster. The hardware is also compatible with the current driver,
so add MT7622 as one of the compatible string list.

Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-10 01:29:53 +02:00
Sean Wang
862e0104f4 cpufreq: mediatek: add cleanups with the more generic naming
Since more MediaTek SoCs can be supported with the cpufreq driver and not
limited to MT8173, a couple of cleanups are done here with renaming those
functions and related structures with "mtk" instead of "mt8173".

Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-10 01:29:53 +02:00
Viresh Kumar
209887e6b9 cpufreq: Return 0 from ->fast_switch() on errors
CPUFREQ_ENTRY_INVALID is a special symbol which is used to specify that
an entry in the cpufreq table is invalid. But using it outside of the
scope of the cpufreq table looks a bit incorrect.

We can represent an invalid frequency by writing it as 0 instead if we
need. Note that it is already done that way for the return value of the
->get() callback.

Lets do the same for ->fast_switch() and not use CPUFREQ_ENTRY_INVALID
outside of the scope of cpufreq table.

Also update the comment over cpufreq_driver_fast_switch() to clearly
mention what this returns.

None of the drivers return CPUFREQ_ENTRY_INVALID as of now from
->fast_switch() callback and so we don't need to update any of those.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-10 01:26:35 +02:00
Rafael J. Wysocki
d77d4888cb cpufreq: intel_pstate: Shorten a couple of long names
The names of the INTEL_PSTATE_DEFAULT_SAMPLING_INTERVAL symbol and
the get_target_pstate_use_cpu_load() function don't need to be so
long any more, so make them shorter.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-10 01:09:16 +02:00
Rafael J. Wysocki
a891283e56 cpufreq: intel_pstate: Simplify intel_pstate_adjust_pstate()
Since there is only one P-state selection routine in intel_pstate
now, make intel_pstate_adjust_pstate() call it directly and drop
the target_pstate argument from that function.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-10 01:08:56 +02:00
Khiem Nguyen
034def597b cpufreq: rcar: Add support for R8A7795 SoC
After the commit "a399dc9fc50 cpufreq: shmobile: Use generic platdev
driver", will use cpufreq-dt-platdev driver to enable cpufreq-dt support.
Hence, follow the implementation to support new R8A7795 SoC.

Signed-off-by: Khiem Nguyen <khiem.nguyen.xt@rvc.renesas.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-08 17:09:54 +02:00
Rafael J. Wysocki
3714c281c6 Merge v4.13 intel_pstate fixes. 2017-08-04 14:28:58 +02:00
Finley Xiao
319af40a00 cpufreq: dt: Add rk3328 compatible to use generic cpufreq driver
This patch adds the rk3328 compatible string for supporting
the generic cpufreq driver on RK3328.

Signed-off-by: Finley Xiao <finley.xiao@rock-chips.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-04 14:22:43 +02:00
Srinivas Pandruvada
7bde2d5001 cpufreq: intel_pstate: Improve IO performance with per-core P-states
In the current implementation, the response latency between seeing
SCHED_CPUFREQ_IOWAIT set and the actual P-state adjustment can be up
to 10ms.  It can be reduced by bumping up the P-state to the max at
the time SCHED_CPUFREQ_IOWAIT is passed to intel_pstate_update_util().
With this change, the IO performance improves significantly.

For a simple "grep -r . linux" (Here linux is the kernel source
folder) with caches dropped every time on a Broadwell Xeon workstation
with per-core P-states, the user and system time is shorter by as much
as 30% - 40%.

The same performance difference was not observed on clients that don't
support per-core P-state.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-04 13:58:57 +02:00
Rafael J. Wysocki
8a05c3115d Merge branches 'pm-cpufreq-x86', 'pm-cpufreq-docs' and 'intel_pstate'
* pm-cpufreq-x86:
  cpufreq: x86: Make scaling_cur_freq behave more as expected

* pm-cpufreq-docs:
  cpufreq: docs: Add missing cpuinfo_cur_freq description

* intel_pstate:
  cpufreq: intel_pstate: Drop ->get from intel_pstate structure
2017-08-03 20:29:24 +02:00
Viresh Kumar
99d14d0e16 cpufreq: Process remote callbacks from any CPU if the platform permits
On many platforms, CPUs can do DVFS across cpufreq policies. i.e CPU
from policy-A can change frequency of CPUs belonging to policy-B.

This is quite common in case of ARM platforms where we don't
configure any per-cpu register.

Add a flag to identify such platforms and update
cpufreq_can_do_remote_dvfs() to allow remote callbacks if this flag is
set.

Also enable the flag for cpufreq-dt driver which is used only on ARM
platforms currently.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Saravana Kannan <skannan@codeaurora.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-01 14:24:54 +02:00
Viresh Kumar
674e75411f sched: cpufreq: Allow remote cpufreq callbacks
With Android UI and benchmarks the latency of cpufreq response to
certain scheduling events can become very critical. Currently, callbacks
into cpufreq governors are only made from the scheduler if the target
CPU of the event is the same as the current CPU. This means there are
certain situations where a target CPU may not run the cpufreq governor
for some time.

One testcase to show this behavior is where a task starts running on
CPU0, then a new task is also spawned on CPU0 by a task on CPU1. If the
system is configured such that the new tasks should receive maximum
demand initially, this should result in CPU0 increasing frequency
immediately. But because of the above mentioned limitation though, this
does not occur.

This patch updates the scheduler core to call the cpufreq callbacks for
remote CPUs as well.

The schedutil, ondemand and conservative governors are updated to
process cpufreq utilization update hooks called for remote CPUs where
the remote CPU is managed by the cpufreq policy of the local CPU.

The intel_pstate driver is updated to always reject remote callbacks.

This is tested with couple of usecases (Android: hackbench, recentfling,
galleryfling, vellamo, Ubuntu: hackbench) on ARM hikey board (64 bit
octa-core, single policy). Only galleryfling showed minor improvements,
while others didn't had much deviation.

The reason being that this patch only targets a corner case, where
following are required to be true to improve performance and that
doesn't happen too often with these tests:

- Task is migrated to another CPU.
- The task has high demand, and should take the target CPU to higher
  OPPs.
- And the target CPU doesn't call into the cpufreq governor until the
  next tick.

Based on initial work from Steve Muckle.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Saravana Kannan <skannan@codeaurora.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-01 14:24:53 +02:00
Rafael J. Wysocki
f5c13f44c7 cpufreq: intel_pstate: Drop INTEL_PSTATE_HWP_SAMPLING_INTERVAL
After commit 62611cb912 (intel_pstate: delete scheduler hook in HWP
mode) the INTEL_PSTATE_HWP_SAMPLING_INTERVAL is not used anywhere in
the code, so drop it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-01 14:14:03 +02:00