On platforms where the Low Power S0 Idle _DSM interface is used,
on wakeup from suspend-to-idle, when it is known that the ACPI SCI
has triggered while suspended, dispatch the EC GPE in order to catch
all EC events that may have triggered the wakeup before carrying out
the noirq phase of device resume.

That is needed to handle power button wakeup on some platforms where
the EC goes into a low-power mode during suspend-to-idle and while in
that mode it will discard events after a timeout.  If that timeout is
shorter than the time it takes to complete the noirq resume of
devices, looking for EC events after the latter is too late.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reported-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wendy Wang <wendy.wang@intel.com>

acpi_ec.gpe is "unsigned long", hence treating it as "u32" would expose
the wrong half on big-endian 64-bit systems.  Fix this by changing its
type to "u32" and removing the cast, as all other code already uses u32
or sometimes even only u8.

Fixes: 1195a098168fcacf (ACPI: Provide /sys/kernel/debug/ec/...)
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

* acpi-ec:
  ACPI / EC: Fix regression related to PM ops support in ECDT device

On platforms (ASUS X550ZE and possibly all ASUS X series) with valid ECDT
EC but invalid DSDT EC, EC PM ops won't be invoked as ECDT EC is not an
ACPI device. Thus the following commit actually removed post-resume
acpi_ec_enable_event() invocation for such platforms, and triggered a
regression on them that after being resumed, EC (actually should be ECDT)
driver stops handling EC events:

 Commit: c2b46d679b30c5c0d7eb47a21085943242bdd8dc
 Subject: ACPI / EC: Add PM operations to improve event handling for resume process

Notice that the root cause actually is "ECDT is not an ACPI device" rather
than "the timing of acpi_ec_enable_event() invocation", this patch fixes
this issue by enumerating ECDT EC as an ACPI device. Due to the existence
of the noirq stage, the ability of tuning the timing of
acpi_ec_enable_event() invocation is still meaningful.

This patch is a little bit different from the posted fix by moving
acpi_config_boot_ec() from acpi_ec_ecdt_start() to acpi_ec_add() to make
sure that EC event handling won't be stopped as long as the ACPI EC driver
is bound. Thus the following sequence shouldn't disable EC event handling:
unbind,suspend,resume,bind.

Fixes: c2b46d679b30 (ACPI / EC: Add PM operations to improve event handling for resume process)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=196847
Reported-by: Luya Tshimbalanga <luya@fedoraproject.org>
Tested-by: Luya Tshimbalanga <luya@fedoraproject.org>
Cc: 4.9+ <stable@vger.kernel.org> # 4.9+
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Add functionality to read LPIT table, which provides:

 - Sysfs interface to read residency counters via
   /sys/devices/system/cpu/cpuidle/low_power_idle_cpu_residency_us
   /sys/devices/system/cpu/cpuidle/low_power_idle_system_residency_us

Here the count "low_power_idle_cpu_residency_us" shows the time spent
by CPU package in low power state.  This is read via MSR interface,
which points to MSR for PKG C10.

Here the count "low_power_idle_system_residency_us" show the count the
system was in low power state. This is read via MMIO interface. This
is mapped to SLP_S0 residency on modern Intel systems. This residency
is achieved only when CPU is in PKG C10 and all functional blocks are
in low power state.

It is possible that none of the above counters present or anyone of the
counter present or all counters present.

For example: On my Kabylake system both of the above counters present.
After suspend to idle these counts updated and prints:

 6916179
 6998564

This counter can be read by tools like turbostat to display. Or it can
be used to debug, if modern systems are reaching desired low power state.

 - Provides an interface to read residency counter memory address

   This address can be used to get the base address of PMC memory
   mapped IO.  This is utilized by intel_pmc_core driver to print
   more debug information.

In addition, to avoid code duplication to read iomem, removed the read of
iomem from acpi_os_read_memory() in osl.c and made a common function
acpi_os_read_iomem(). This new function is used for reading iomem in
in both osl.c and acpi_lpit.c.

Link: http://www.uefi.org/sites/default/files/resources/Intel_ACPI_Low_Power_S0_Idle.pdf
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

* acpi-x86:
  ACPI / boot: Add number of legacy IRQs to debug output
  ACPI / boot: Correct address space of __acpi_map_table()
  ACPI / boot: Don't define unused variables

* acpi-soc:
  ACPI / LPSS: Don't abort ACPI scan on missing mem resource

* acpi-pmic:
  ACPI / PMIC: xpower: Do pinswitch magic when reading GPADC

* acpi-apple:
  spi: Use Apple device properties in absence of ACPI resources
  ACPI / scan: Recognize Apple SPI and I2C slaves
  ACPI / property: Support Apple _DSM properties
  ACPI / property: Don't evaluate objects for devices w/o handle
  treewide: Consolidate Apple DMI checks

Commit 2a5708409e4e (ACPI / EC: Fix a gap that ECDT EC cannot handle
EC events) introduced acpi_ec_ecdt_start(), but that function is
invoked before acpi_ec_query_init(), which is too early.  This causes
the kernel to crash if an EC event occurs after boot, when ec_query_wq
is not valid:

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000102
 ...
 Workqueue: events acpi_ec_event_handler
 task: ffff9f539790dac0 task.stack: ffffb437c0e10000
 RIP: 0010:__queue_work+0x32/0x430

Normally, the DSDT EC should always be valid, so acpi_ec_ecdt_start()
is actually a no-op in the majority of cases.  However, commit
c712bb58d827 (ACPI / EC: Add support to skip boot stage DSDT probe)
caused the probing of the DSDT EC as the "boot EC" to be skipped when
the ECDT EC is valid and uncovered the bug.

Fix this issue by invoking acpi_ec_ecdt_start() after acpi_ec_query_init()
in acpi_ec_init().

Link: https://jira01.devtools.intel.com/browse/LCK-4348
Fixes: 2a5708409e4e (ACPI / EC: Fix a gap that ECDT EC cannot handle EC events)
Fixes: c712bb58d827 (ACPI / EC: Add support to skip boot stage DSDT probe)
Reported-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: Feng Chenzhou <chenzhoux.feng@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

While the rest of the world has standardized on _DSD as the way to store
device properties in AML (introduced with ACPI 5.1 in 2014), Apple has
been using a custom _DSM to achieve the same for much longer (ever since
they switched from DeviceTree-based PowerPC to Intel in 2005, verified
with MacOS X 10.4.11).

The theory of operation on macOS is as follows:  AppleACPIPlatform.kext
invokes mergeEFIproperties() and mergeDSMproperties() for each device to
merge properties conveyed by EFI drivers as well as properties stored in
AML into the I/O Kit registry from which they can be retrieved by
drivers.  We've been supporting EFI properties since commit 58c5475aba67
("x86/efi: Retrieve and assign Apple device properties").  The present
commit adds support for _DSM properties, thereby completing our support
for Apple device properties.  The _DSM properties are made available
under the primary fwnode, the EFI properties under the secondary fwnode.
So for devices which possess both property types, they can all be
elegantly accessed with the uniform API in <linux/property.h>.

Until recently we had no need to support _DSM properties, they contained
only uninteresting garbage.  The situation has changed with MacBooks and
MacBook Pros introduced since 2015:  Their keyboard is attached with SPI
instead of USB and the _CRS data which is necessary to initialize the
spi driver only contains valid information if OSPM responds "false" to
_OSI("Darwin").  If OSPM responds "true", _CRS is empty and the spi
driver fails to initialize.  The rationale is very simple, Apple only
cares about macOS and Windows:  On Windows, _CRS contains valid data,
whereas on macOS it is empty.  Instead, macOS gleans the necessary data
from the _DSM properties.

Since Linux deliberately defaults to responding "true" to _OSI("Darwin"),
we need to emulate macOS' behaviour by initializing the spi driver with
data returned by the _DSM.

An out-of-tree driver for the SPI keyboard exists which currently binds
to the ACPI device, invokes the _DSM, parses the returned package and
instantiates an SPI device with the data gleaned from the _DSM:
https://github.com/cb22/macbook12-spi-driver/commit/9a416d699ef4
https://github.com/cb22/macbook12-spi-driver/commit/0c34936ed9a1

By adding support for Apple's _DSM properties in generic ACPI code, the
out-of-tree driver will be able to register as a regular SPI driver,
significantly reducing its amount of code and improving its chances to
be mainlined.

The SPI keyboard will not be the only user of this commit:  E.g. on the
MacBook8,1, the UART-attached Bluetooth device likewise returns empty
_CRS data if OSPM returns "true" to _OSI("Darwin").

The _DSM returns a Package whose format unfortunately deviates slightly
from the _DSD spec:  The properties are marshalled up in a single Package
as alternating key/value elements, unlike _DSD which stores them as a
Package of 2-element Packages.  The present commit therefore converts
the Package to _DSD format and the ACPI core can then treat the data as
if Apple would follow the standard.

Well, except for one small annoyance:  The properties returned by the
_DSM only ever have one of two types, Integer or Buffer.  The former is
retrievable as usual with device_property_read_u64(), but the latter is
not part of the _DSD spec and it is not possible to retrieve Buffer
properties with the device_property_read_*() functions due to the type
checking performed in drivers/acpi/property.c.  It is however possible
to retrieve them with acpi_dev_get_property().  Apple is using the
Buffer type somewhat sloppily to store null-terminated strings but also
integers.  The real data type is not distinguishable by the ACPI core
and the onus is on the caller to use the contents of the Buffer in an
appropriate way.

In case Apple moves to _DSD in the future, this commit first checks for
_DSD and falls back to _DSM only if _DSD is not found.

Tested-by: Ronald Tschalär <ronald@innovation.ch>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Commit eed4d47efe95 (ACPI / sleep: Ignore spurious SCI wakeups from
suspend-to-idle) introduced acpi_freeze_sync() whose purpose is to
flush all of the processing of possible wakeup events signaled via
the ACPI SCI.  However, it doesn't flush the query workqueue used
by the EC driver, so the events generated by the EC may not be
processed timely which leads to issues (increased overhead at least,
lost events possibly).

To fix that introduce acpi_ec_flush_work() that will flush all of
the outstanding EC work and call it from acpi_freeze_sync().

Fixes: eed4d47efe95 (ACPI / sleep: Ignore spurious SCI wakeups from suspend-to-idle)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Pull device properties framework updates from Rafael Wysocki:
 "These mostly rearrange the device properties core code and add a few
  helper functions to it as a foundation for future work.

  Specifics:

   - Rearrange the core device properties code by moving the code
     specific to each supported platform configuration framework (ACPI,
     DT and build-in) into a separate file (Sakari Ailus).

   - Add helper functions for accessing device properties in a
     firmware-agnostic way (Sakari Ailus, Kieran Bingham)"

* tag 'devprop-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  device property: Add fwnode_graph_get_port_parent
  device property: Add FW type agnostic fwnode_graph_get_remote_node
  device property: Introduce fwnode_device_is_available()
  device property: Move fwnode graph ops to firmware specific locations
  device property: Move FW type specific functionality to FW specific files
  ACPI: Constify argument to acpi_device_is_present()