We do not have a strict read/write order requirement while accessing
PCC subspace. The only requirement is all access should be committed
before triggering the PCC doorbell to transfer the ownership of PCC
to the platform and this requirement is enforced by the PCC driver.
Profiling on a many core system shows improvement of about 1.8us on
average per freq change request(about 10% improvement on average).
Since these operations are executed while holding the pcc_lock,
reducing this time helps the CPPC implementation to scale much
better as the number of cores increases.
Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org>
Acked-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpc_read and cpc_write are used while holding the pcc_lock spin_lock,
so they need to be as fast as possible. acpi_os_read/write_memory
APIs linearly search through a list for cached mapping which is
quite expensive. Since the PCC subspace is already mapped into
virtual address space during initialization, we can just add the
offset and access the necessary CPPC registers.
This patch + similar changes to PCC driver reduce the time per freq.
transition from around 200us to about 20us for the CPPC cpufreq
driver.
Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org>
Acked-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Previously the send_pcc_cmd() code checked if the
PCC operation had completed before returning from
the function. This check was performed regardless
of the PCC op type (i.e. Read/Write). Knowing
the type of cmd can be used to optimize the check
and avoid needless waiting. e.g. with Write ops,
the actual Writing is done before calling send_pcc_cmd().
And the subsequent Writes will check if the channel is
free at the entry of send_pcc_cmd() anyway.
However, for Read cmds, we need to wait for the cmd
completion bit to be flipped, since the actual Read
ops follow after returning from the send_pcc_cmd(). So,
only do the looping check at the end for Read ops.
Also, instead of using udelay() calls, use ktime as a
means to check for deadlines. The current deadline
in which the Remote should flip the cmd completion bit
is defined as N * Nominal latency. Where N is arbitrary
and large enough to work on slow emulators and Nominal
latency comes from the ACPI table (PCCT). This helps
in working around the CONFIG_HZ effects on udelay()
and also avoids needing different ACPI tables for Silicon
and Emulation platforms.
Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The quirk to get "acpi_backlight=vendor" behavior by default on the
Dell Inspiron 5737 was added before we started doing
"acpi_backlight=native" by default on Win8 ready machines.
Since we now avoid using acpi-video as backlight driver on these machines
by default (using the native driver instead) we no longer need this quirk.
Moreover the vendor driver does not work after a suspend/resume where
as the native driver does.
This reverts commit 08a56226d8 (ACPI / video: Add Dell Inspiron 5737
to the blacklist).
Link: https://bugzilla.kernel.org/show_bug.cgi?id=111061
Cc: 3.19+ <stable@vger.kernel.org> # 3.19+
Reported-and-tested-by: erusan@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pull more power management and ACPI updates from Rafael Wysocki:
"This includes fixes on top of the previous batch of PM+ACPI updates
and some new material as well.
From the new material perspective the most significant are the driver
core changes that should allow USB devices to stay suspended over
system suspend/resume cycles if they have been runtime-suspended
already beforehand. Apart from that, ACPICA is updated to upstream
revision 20160108 (cosmetic mostly, but including one fixup on top of
the previous ACPICA update) and there are some devfreq updates the
didn't make it before (due to timing).
A few recent regressions are fixed, most importantly in the cpuidle
menu governor and in the ACPI backlight driver and some x86 platform
drivers depending on it.
Some more bugs are fixed and cleanups are made on top of that.
Specifics:
- Modify the driver core and the USB subsystem to allow USB devices
to stay suspended over system suspend/resume cycles if they have
been runtime-suspended already beforehand and fix some bugs on top
of these changes (Tomeu Vizoso, Rafael Wysocki).
- Update ACPICA to upstream revision 20160108, including updates of
the ACPICA's copyright notices, a code fixup resulting from a
regression fix that was necessary in the upstream code only (the
regression fixed by it has never been present in Linux) and a
compiler warning fix (Bob Moore, Lv Zheng).
- Fix a recent regression in the cpuidle menu governor that broke it
on practically all architectures other than x86 and make a couple
of optimizations on top of that fix (Rafael Wysocki).
- Clean up the selection of cpuidle governors depending on whether or
not the kernel is configured for tickless systems (Jean Delvare).
- Revert a recent commit that introduced a regression in the ACPI
backlight driver, address the problem it attempted to fix in a
different way and revert one more cosmetic change depending on the
problematic commit (Hans de Goede).
- Add two more ACPI backlight quirks (Hans de Goede).
- Fix a few minor problems in the core devfreq code, clean it up a
bit and update the MAINTAINERS information related to it (Chanwoo
Choi, MyungJoo Ham).
- Improve an error message in the ACPI fan driver (Andy Lutomirski).
- Fix a recent build regression in the cpupower tool (Shreyas
Prabhu)"
* tag 'pm+acpi-4.5-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (32 commits)
cpuidle: menu: Avoid pointless checks in menu_select()
sched / idle: Drop default_idle_call() fallback from call_cpuidle()
cpupower: Fix build error in cpufreq-info
cpuidle: Don't enable all governors by default
cpuidle: Default to ladder governor on ticking systems
time: nohz: Expose tick_nohz_enabled
ACPICA: Update version to 20160108
ACPICA: Silence a -Wbad-function-cast warning when acpi_uintptr_t is 'uintptr_t'
ACPICA: Additional 2016 copyright changes
ACPICA: Reduce regression fix divergence from upstream ACPICA
ACPI / video: Add disable_backlight_sysfs_if quirk for the Toshiba Satellite R830
ACPI / video: Revert "thinkpad_acpi: Use acpi_video_handles_brightness_key_presses()"
ACPI / video: Document acpi_video_handles_brightness_key_presses() a bit
ACPI / video: Fix using an uninitialized mutex / list_head in acpi_video_handles_brightness_key_presses()
ACPI / video: Revert "ACPI / video: driver must be registered before checking for keypresses"
ACPI / fan: Improve acpi_device_update_power error message
ACPI / video: Add disable_backlight_sysfs_if quirk for the Toshiba Portege R700
cpuidle: menu: Fix menu_select() for CPUIDLE_DRIVER_STATE_START == 0
MAINTAINERS: Add devfreq-event entry
MAINTAINERS: Add missing git repository and directory for devfreq
...
* pm-core:
driver core: Avoid NULL pointer dereferences in device_is_bound()
platform: Do not detach from PM domains on shutdown
USB / PM: Allow USB devices to remain runtime-suspended when sleeping
PM / sleep: Go direct_complete if driver has no callbacks
PM / Domains: add setter for dev.pm_domain
device core: add device_is_bound()
Do not pass the return value of strtoul() to the ACPI_TO_POINTER()
macro to avoid a -Wbad-function-cast warning.
Signed-off-by: Sascha Wildner <saw@online.de>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Linux has been fixed during 20151218 release cycle by reverting wrong code
in the following commit:
ACPICA commit: 071eff738c59eda1792ac24b3b688b61691d7e7c
Subject: Add per-table execution of module-level code, early region
handlers
While upstream ACPICA fixes later in the following commit:
ACPICA commit: bf6cfddb4784c349f781758981b207253b5a1252
Subject: Fix for module-level-code regression introduced in 20151218
This results in the divergences and this patch is meant to reduce such
divergences. Lv Zheng.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
If acpi_video_handles_brightness_key_presses() was called before
acpi_video_register(), it would use the video_list mutex / list_head
uninitialized.
This patch fixes this by using DEFINE_MUTEX / LIST_HEAD when declaring
these, instead of initializing them runtime from acpi_video_register().
Fixes: 90b066b15e "ACPI / video: Add a acpi_video_handles_brightness_key_presses() helper"
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
On systems with an intel video opcode region, the completion used in the
patch this commit reverts will only complete if the i915 driver loads.
If for some reason the i915 driver never loads calls to
acpi_video_handles_brightness_key_presses() may be delayed indefinitely.
This reverts commit aecbd9b1bf ("ACPI / video: driver must be registered
before checking for keypresses") fixing this.
This reintroduces a potential NULL pointer deref due to using an
uninitalized mutex, this is fixed differently in a follow-up patch.
Fixes: aecbd9b1bf (ACPI / video: driver must be registered before checking for keypresses)
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
On my laptop, I see "Setting initial power state" on boot. It's a
firmware bug on my laptop, but the message made me think that the
initial power state was bogus and the driver fixed it. The error
actually means that the driver failed to set the initial power
state. Fix the message.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pull libnvdimm updates from Dan Williams:
"The bulk of this has appeared in -next and independently received a
build success notification from the kbuild robot. The 'for-4.5/block-
dax' topic branch was rebased over the weekend to drop the "block
device end-of-life" rework that Al would like to see re-implemented
with a notifier, and to address bug reports against the badblocks
integration.
There is pending feedback against "libnvdimm: Add a poison list and
export badblocks" received last week. Linda identified some localized
fixups that we will handle incrementally.
Summary:
- Media error handling: The 'badblocks' implementation that
originated in md-raid is up-levelled to a generic capability of a
block device. This initial implementation is limited to being
consulted in the pmem block-i/o path. Later, 'badblocks' will be
consulted when creating dax mappings.
- Raw block device dax: For virtualization and other cases that want
large contiguous mappings of persistent memory, add the capability
to dax-mmap a block device directly.
- Increased /dev/mem restrictions: Add an option to treat all
io-memory as IORESOURCE_EXCLUSIVE, i.e. disable /dev/mem access
while a driver is actively using an address range. This behavior
is controlled via the new CONFIG_IO_STRICT_DEVMEM option and can be
overridden by the existing "iomem=relaxed" kernel command line
option.
- Miscellaneous fixes include a 'pfn'-device huge page alignment fix,
block device shutdown crash fix, and other small libnvdimm fixes"
* tag 'libnvdimm-for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (32 commits)
block: kill disk_{check|set|clear|alloc}_badblocks
libnvdimm, pmem: nvdimm_read_bytes() badblocks support
pmem, dax: disable dax in the presence of bad blocks
pmem: fail io-requests to known bad blocks
libnvdimm: convert to statically allocated badblocks
libnvdimm: don't fail init for full badblocks list
block, badblocks: introduce devm_init_badblocks
block: clarify badblocks lifetime
badblocks: rename badblocks_free to badblocks_exit
libnvdimm, pmem: move definition of nvdimm_namespace_add_poison to nd.h
libnvdimm: Add a poison list and export badblocks
nfit_test: Enable DSMs for all test NFITs
md: convert to use the generic badblocks code
block: Add badblock management for gendisks
badblocks: Add core badblock management code
block: fix del_gendisk() vs blkdev_ioctl crash
block: enable dax for raw block devices
block: introduce bdev_file_inode()
restrict /dev/mem to idle io memory ranges
arch: consolidate CONFIG_STRICT_DEVM in lib/Kconfig.debug
...
* acpi-scan:
ACPI: Fix white space in a structure definition
ACPI / utils: Add acpi_dev_present()
ACPI / scan: Fix acpi_bus_id_list bookkeeping
ACPI / scan: set status to 0 if _STA failed
* acpi-bus:
ACPI / bus: Show _OSC UUID when _OSC fails
ACPI / bus: Tidy up _OSC error spacing
* acpi-osl:
ACPI / OSL: Add kerneldoc comments to memory mapping functions
* acpi-pm:
ACPI / PM: Support D3 COLD device in old BIOS for ZPODD
* acpi-video:
ACPI / video: driver must be registered before checking for keypresses
ACPI / video: Add a quirk to force acpi-video backlight on SAMSUNG 530U4E/540U4E
ACPI / video: Add quirks for the Dell Vostro V131
ACPI / video: Add a module option to disable the reporting of keypresses
thinkpad_acpi: Use acpi_video_handles_brightness_key_presses()
dell-wmi: Use acpi_video_handles_brightness_key_presses()
ACPI / video: Add a acpi_video_handles_brightness_key_presses() helper
* acpica: (43 commits)
ACPICA: Drop Linux-specific waking vector functions
ACPICA: Update version to 20151218
ACPICA: Add per-table execution of module-level code
ACPICA: Add "root node" case to the ACPI name repair code
ACPICA: Events: Introduce ACPI_REG_DISCONNECT invocation to acpi_ev_execute_reg_methods()
ACPICA: Events: Enhance acpi_ev_execute_reg_method() to ensure no _REG evaluations can happen during OS early boot stages
ACPICA: Events: Split acpi_ev_associate_reg_method() from region initialization code
ACPICA: Events: Fix an issue that region object is re-attached to another scope when it is already attached
ACPICA: Utilities: Reorder initialization code
ACPICA: Events: Uses common_notify for address space handlers
ACPICA: Events: Deploys acpi_ev_find_region_handler()
ACPICA: Cleanup code related to the per-table module level improvement
ACPICA: Update for CondRefOf and RefOf operators
ACPICA: Update internal #defines for ObjectType operator. No functional change
ACPICA: Update parameter type for ObjectType operator
ACPICA: Parser: Fix for SuperName method invocation
ACPICA: Parser: Add constants for internal namepath function
ACPICA: iasl/Disassembler: Support ASL ElseIf operator
ACPICA: Add new exception code, AE_IO_ERROR
ACPICA: Tools: Add spacing and missing options in acpibin tool
...
* acpi-debug:
ACPI / debugger: Fix a redundant mutex unlock issue in acpi_aml_open()
ACPI / debugger: copy_to_user doesn't return errors
ACPI / debugger: remove some unneeded conditions
ACPI / debugger: Fix an issue a flag is modified without locking
ACPI / debugger: Add module support for ACPI debugger
tools/power/acpi: Add userspace AML interface support
ACPI / debugger: Add IO interface to access debugger functionalities
ACPICA: Debugger: Fix runtime stub issues of ACPI_DEBUGGER_EXEC using different stub mechanism
ACPICA: Debugger: Convert some mechanisms to OSPM specific
ACPICA: Debugger: Remove unnecessary status check
* acpi-soc:
PM / clk: don't leave clocks enabled when driver not bound
i2c: dw: Add APM X-Gene ACPI I2C device support
ACPI / APD: Add APM X-Gene ACPI I2C device support
ACPI / LPSS: change 'does not have' to 'has' in comment
Revert "dmaengine: dw: platform: provide platform data for Intel"
dmaengine: dw: return immediately from IRQ when DMA isn't in use
dmaengine: dw: platform: power on device on shutdown
ACPI / LPSS: override power state for LPSS DMA device
ACPI / LPSS: power on when probe() and otherwise when remove()
ACPI / LPSS: do delay for all LPSS devices when D3->D0
ACPI / LPSS: allow to use specific PM domain during ->probe()
Revert "ACPI / LPSS: allow to use specific PM domain during ->probe()"
device core: add BUS_NOTIFY_DRIVER_NOT_BOUND notification
x86/platform/iosf_mbi: Remove duplicate definitions
Conflicts:
drivers/i2c/busses/i2c-designware-platdrv.c
Prakash, Prashanth
Ashwin Chaugule
Rafael J. Wysocki
Hans de Goede
Tetsuo Handa
Linus Torvalds
Lv Zheng
Bob Moore
Andy Lutomirski