Commit Graph

117 Commits

Author SHA1 Message Date
Rafael J. Wysocki b7fbf4cebd ACPI: glue: Rearrange find_child_checks()
Notice that it is not necessary to evaluate _STA in find_child_checks()
if the device is expected to have children, but there are none, so
move the children check to the front of the function.

Also notice that FIND_CHILD_MIN_SCORE can be returned right away if
_STA is missing, so make the function do so.

Finally, replace the ternary operator in the return statement argument
with an if () and a standalone return which is somewhat easier to
follow.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-05-12 16:52:32 +02:00
Rafael J. Wysocki 3b2b49e6df Revert "ACPI: scan: Release PM resources blocked by unused objects"
Revert commit c10383e8dd ("ACPI: scan: Release PM resources blocked
by unused objects"), because it causes boot issues to appear on some
platforms.

Reported-by: Kyle D. Pelton <kyle.d.pelton@intel.com>
Reported-by: Saranya Gopal <saranya.gopal@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-11-17 17:05:41 +01:00
Rafael J. Wysocki c3fb46600e Merge branches 'acpi-glue', 'acpi-pnp', 'acpi-processor' and 'acpi-soc'
Merge updates of the code associating ACPI device objects with
devices and PNP code, processor driver, and Intel LPSS driver updates
for 5.16-rc1:

 - Make the association of ACPI device objects with PCI devices more
   straightforward and simplify the code doing that for all devices
   in general (Rafael Wysocki).

 - Use acpi_device_adr() in acpi_find_child_device() instead of
   evaluating _ADR (Rafael Wysocki).

 - Drop duplicate device IDs from PNP device IDs list (Krzysztof
   Kozlowski).

 - Allow acpi_idle_play_dead() to use C3 on AMD processors (Richard
   Gong).

 - Use ACPI_COMPANION() to simplify code in the ACPI driver for Intel
   SoCs (Rafael Wysocki).

* acpi-glue:
  ACPI: glue: Use acpi_device_adr() in acpi_find_child_device()
  ACPI: glue: Look for ACPI bus type only if ACPI companion is not known
  ACPI: glue: Drop cleanup callback from struct acpi_bus_type
  PCI: ACPI: Drop acpi_pci_bus

* acpi-pnp:
  ACPI: PNP: remove duplicated BRI0A49 and BDP3336 entries

* acpi-processor:
  ACPI: processor idle: Allow playing dead in C3 state

* acpi-soc:
  ACPI: LPSS: Use ACPI_COMPANION() directly
2021-11-02 18:36:40 +01:00
Rafael J. Wysocki 61a3c78d99 ACPI: glue: Use acpi_device_adr() in acpi_find_child_device()
Instead of evaluating _ADR in acpi_find_child_device(), use the
observation that it has already been evaluated and the value returned
by it has been stored in the pnp.type.bus_address field of the ACPI
device object at hand.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-10-28 16:53:24 +02:00
Rafael J. Wysocki c10383e8dd ACPI: scan: Release PM resources blocked by unused objects
On some systems the ACPI namespace contains device objects that are
not used in certain configurations of the system.  If they start off
in the D0 power state configuration, they will stay in it until the
system reboots, because of the lack of any mechanism possibly causing
their configuration to change.  If that happens, they may prevent
some power resources from being turned off or generally they may
prevent the platform from getting into the deepest low-power states
thus causing some energy to be wasted.

Address this issue by changing the configuration of unused ACPI
device objects to the D3cold power state one after carrying out
the ACPI-based enumeration of devices.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=214091
Link: https://lore.kernel.org/linux-acpi/20211007205126.11769-1-mario.limonciello@amd.com/
Reported-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mario Limonciello <mario.limonciello@amd.com>
2021-10-13 19:57:01 +02:00
Rafael J. Wysocki 2ef5236660 ACPI: glue: Look for ACPI bus type only if ACPI companion is not known
Notice that it is not necessary to look for the "ACPI bus type" of
the device in acpi_device_notify() if the device's ACPI companion
is set upfront, so modify the code to do that lookup only if it is
necessary to find the ACPI companion.

Also notice that if the device's ACPI companion is not set upfront
in acpi_device_notify(), the device cannot be either a PCI one or a
platform one, so check for these bus types only if the device's
ACPI companion is set.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Ferry Toth <fntoth@gmail.com>
2021-09-27 17:01:37 +02:00
Rafael J. Wysocki c4d19838d8 ACPI: glue: Drop cleanup callback from struct acpi_bus_type
Since PCI was the only user of the ->cleanup callback in struct
acpi_bus_type and it is not using struct acpi_bus_type any more,
drop that callback from there and update acpi_device_notify_remove()
accordingly.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Ferry Toth <fntoth@gmail.com>
2021-09-27 17:01:25 +02:00
Rafael J. Wysocki 4795448117 PCI: ACPI: Drop acpi_pci_bus
The acpi_pci_bus structure was used primarily for running
acpi_pci_find_companion() during PCI device objects registration,
but after commit 375553a932 ("PCI: Setup ACPI fwnode early and at
the same time with OF") that function is called by pci_setup_device()
via pci_set_acpi_fwnode(), which happens before calling
pci_device_add() on the new PCI device object, so its ACPI companion
has been set already when acpi_device_notify() runs and it will never
call ->find_companion() from acpi_pci_bus.

For this reason, modify acpi_device_notify() and
acpi_device_notify_remove() to call pci_acpi_setup() and
pci_acpi_cleanup(), respectively, directly on PCI device objects
and drop acpi_pci_bus altogether.

While at it, notice that pci_acpi_setup() and pci_acpi_cleanup()
can obtain the ACPI companion pointer, which is guaranteed to not
be NULL, from their callers and modify them to work that way so
as to reduce the number of redundant checks somewhat.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Ferry Toth <fntoth@gmail.com>
2021-09-27 17:00:21 +02:00
Rafael J. Wysocki d0b8e39831 ACPI: glue: Eliminate acpi_platform_notify()
Get rid of acpi_platform_notify() which is redundant and
make device_platform_notify() in the driver core call
acpi_device_notify() and acpi_device_notify_remove() directly.

No functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2021-07-16 19:17:04 +02:00
Rafael J. Wysocki 7d625e5b14 ACPI: glue: Change return type of two functions to void
Since the return values of acpi_device_notify() and
acpi_device_notify_remove() are discarded by their only caller,
change their return type to void.

No functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2021-07-16 19:17:04 +02:00
Rafael J. Wysocki 42878a9f0f ACPI: glue: Rearrange acpi_device_notify()
Make the code flow in acpi_device_notify() more straightforward and
make it use dev_dbg() and acpi_handle_debug() for printing debug
messages.

The only expected functional impact of this change is the content of
the debug messages printed by acpi_device_notify().

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2021-07-16 19:17:04 +02:00
Hanjun Guo e2935abb3a ACPI: glue: Clean up the printing messages
Remove the in house ACPI_GLUE_DEBUG and its related debug message
printing, using pr_debug() instead.

While at it, replace printk() with pr_* to simplify the code.

Signed-off-by: Hanjun Guo <guohanjun@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-06-07 15:36:45 +02:00
Andy Shevchenko 4cbaba4e3e ACPI: bus: Introduce acpi_dev_get() and reuse it in ACPI code
Introduce acpi_dev_get() to have a symmetrical API with acpi_dev_put()
and reuse both in ACPI code in drivers/acpi/.

While at it, use acpi_bus_put_acpi_device() in one place instead of
the above.

Signed-off-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-04-13 15:41:11 +02:00
Thomas Gleixner 55716d2643 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428
Based on 1 normalized pattern(s):

  this file is released under the gplv2

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 68 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531190114.292346262@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:37:16 +02:00
Heikki Krogerus 7847a1455f ACPI / glue: Add acpi_platform_notify() function
Instead of relying on the "platform_notify" callback hook,
introducing separate notification function
acpi_platform_notify() and calling that directly from
drivers core when device entries are added and removed.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-11-26 18:19:11 +01:00
Andy Shevchenko 719cf71cad ACPI / glue: Split dev_is_platform() out of module for wide use
There would be useful to have in future the similar API in platform
core, as we have, for example, for PCI subsystem, to check if device
belongs to it.

Thus, split out conditional to a macro dev_is_platform() for wide use.

No functional change intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-09-10 12:48:50 +02:00
Linus Torvalds 28b47809b2 IOMMU Updates for Linux v4.12
This includes:
 
 	* Some code optimizations for the Intel VT-d driver
 
 	* Code to switch off a previously enabled Intel IOMMU
 
 	* Support for 'struct iommu_device' for OMAP, Rockchip and
 	  Mediatek IOMMUs
 
 	* Some header optimizations for IOMMU core code headers and a
 	  few fixes that became necessary in other parts of the kernel
 	  because of that
 
 	* ACPI/IORT updates and fixes
 
 	* Some Exynos IOMMU optimizations
 
 	* Code updates for the IOMMU dma-api code to bring it closer to
 	  use per-cpu iova caches
 
 	* New command-line option to set default domain type allocated
 	  by the iommu core code
 
 	* Another command line option to allow the Intel IOMMU switched
 	  off in a tboot environment
 
 	* ARM/SMMU: TLB sync optimisations for SMMUv2, Support for using
 	  an IDENTITY domain in conjunction with DMA ops, Support for
 	  SMR masking, Support for 16-bit ASIDs (was previously broken)
 
 	* Various other small fixes and improvements
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Merge tag 'iommu-updates-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull IOMMU updates from Joerg Roedel:

 - code optimizations for the Intel VT-d driver

 - ability to switch off a previously enabled Intel IOMMU

 - support for 'struct iommu_device' for OMAP, Rockchip and Mediatek
   IOMMUs

 - header optimizations for IOMMU core code headers and a few fixes that
   became necessary in other parts of the kernel because of that

 - ACPI/IORT updates and fixes

 - Exynos IOMMU optimizations

 - updates for the IOMMU dma-api code to bring it closer to use per-cpu
   iova caches

 - new command-line option to set default domain type allocated by the
   iommu core code

 - another command line option to allow the Intel IOMMU switched off in
   a tboot environment

 - ARM/SMMU: TLB sync optimisations for SMMUv2, Support for using an
   IDENTITY domain in conjunction with DMA ops, Support for SMR masking,
   Support for 16-bit ASIDs (was previously broken)

 - various other small fixes and improvements

* tag 'iommu-updates-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (63 commits)
  soc/qbman: Move dma-mapping.h include to qman_priv.h
  soc/qbman: Fix implicit header dependency now causing build fails
  iommu: Remove trace-events include from iommu.h
  iommu: Remove pci.h include from trace/events/iommu.h
  arm: dma-mapping: Don't override dma_ops in arch_setup_dma_ops()
  ACPI/IORT: Fix CONFIG_IOMMU_API dependency
  iommu/vt-d: Don't print the failure message when booting non-kdump kernel
  iommu: Move report_iommu_fault() to iommu.c
  iommu: Include device.h in iommu.h
  x86, iommu/vt-d: Add an option to disable Intel IOMMU force on
  iommu/arm-smmu: Return IOVA in iova_to_phys when SMMU is bypassed
  iommu/arm-smmu: Correct sid to mask
  iommu/amd: Fix incorrect error handling in amd_iommu_bind_pasid()
  iommu: Make iommu_bus_notifier return NOTIFY_DONE rather than error code
  omap3isp: Remove iommu_group related code
  iommu/omap: Add iommu-group support
  iommu/omap: Make use of 'struct iommu_device'
  iommu/omap: Store iommu_dev pointer in arch_data
  iommu/omap: Move data structures to omap-iommu.h
  iommu/omap: Drop legacy-style device support
  ...
2017-05-09 15:15:47 -07:00
Linus Torvalds ab182e67ec arm64 updates for 4.12:
- kdump support, including two necessary memblock additions:
   memblock_clear_nomap() and memblock_cap_memory_range()
 
 - ARMv8.3 HWCAP bits for JavaScript conversion instructions, complex
   numbers and weaker release consistency
 
 - arm64 ACPI platform MSI support
 
 - arm perf updates: ACPI PMU support, L3 cache PMU in some Qualcomm
   SoCs, Cortex-A53 L2 cache events and DTLB refills, MAINTAINERS update
   for DT perf bindings
 
 - architected timer errata framework (the arch/arm64 changes only)
 
 - support for DMA_ATTR_FORCE_CONTIGUOUS in the arm64 iommu DMA API
 
 - arm64 KVM refactoring to use common system register definitions
 
 - remove support for ASID-tagged VIVT I-cache (no ARMv8 implementation
   using it and deprecated in the architecture) together with some
   I-cache handling clean-up
 
 - PE/COFF EFI header clean-up/hardening
 
 - define BUG() instruction without CONFIG_BUG
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Catalin Marinas:

 - kdump support, including two necessary memblock additions:
   memblock_clear_nomap() and memblock_cap_memory_range()

 - ARMv8.3 HWCAP bits for JavaScript conversion instructions, complex
   numbers and weaker release consistency

 - arm64 ACPI platform MSI support

 - arm perf updates: ACPI PMU support, L3 cache PMU in some Qualcomm
   SoCs, Cortex-A53 L2 cache events and DTLB refills, MAINTAINERS update
   for DT perf bindings

 - architected timer errata framework (the arch/arm64 changes only)

 - support for DMA_ATTR_FORCE_CONTIGUOUS in the arm64 iommu DMA API

 - arm64 KVM refactoring to use common system register definitions

 - remove support for ASID-tagged VIVT I-cache (no ARMv8 implementation
   using it and deprecated in the architecture) together with some
   I-cache handling clean-up

 - PE/COFF EFI header clean-up/hardening

 - define BUG() instruction without CONFIG_BUG

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (92 commits)
  arm64: Fix the DMA mmap and get_sgtable API with DMA_ATTR_FORCE_CONTIGUOUS
  arm64: Print DT machine model in setup_machine_fdt()
  arm64: pmu: Wire-up Cortex A53 L2 cache events and DTLB refills
  arm64: module: split core and init PLT sections
  arm64: pmuv3: handle pmuv3+
  arm64: Add CNTFRQ_EL0 trap handler
  arm64: Silence spurious kbuild warning on menuconfig
  arm64: pmuv3: use arm_pmu ACPI framework
  arm64: pmuv3: handle !PMUv3 when probing
  drivers/perf: arm_pmu: add ACPI framework
  arm64: add function to get a cpu's MADT GICC table
  drivers/perf: arm_pmu: split out platform device probe logic
  drivers/perf: arm_pmu: move irq request/free into probe
  drivers/perf: arm_pmu: split cpu-local irq request/free
  drivers/perf: arm_pmu: rename irq request/free functions
  drivers/perf: arm_pmu: handle no platform_device
  drivers/perf: arm_pmu: simplify cpu_pmu_request_irqs()
  drivers/perf: arm_pmu: factor out pmu registration
  drivers/perf: arm_pmu: fold init into alloc
  drivers/perf: arm_pmu: define armpmu_init_fn
  ...
2017-05-05 12:11:37 -07:00
Joerg Roedel 2c0248d688 Merge branches 'arm/exynos', 'arm/omap', 'arm/rockchip', 'arm/mediatek', 'arm/smmu', 'arm/core', 'x86/vt-d', 'x86/amd' and 'core' into next 2017-05-04 18:06:17 +02:00
Sricharan R 09515ef5dd of/acpi: Configure dma operations at probe time for platform/amba/pci bus devices
Configuring DMA ops at probe time will allow deferring device probe when
the IOMMU isn't available yet. The dma_configure for the device is
now called from the generic device_attach callback just before the
bus/driver probe is called. This way, configuring the DMA ops for the
device would be called at the same place for all bus_types, hence the
deferred probing mechanism should work for all buses as well.

pci_bus_add_devices    (platform/amba)(_device_create/driver_register)
       |                         |
pci_bus_add_device     (device_add/driver_register)
       |                         |
device_attach           device_initial_probe
       |                         |
__device_attach_driver    __device_attach_driver
       |
driver_probe_device
       |
really_probe
       |
dma_configure

Similarly on the device/driver_unregister path __device_release_driver is
called which inturn calls dma_deconfigure.

This patch changes the dma ops configuration to probe time for
both OF and ACPI based platform/amba/pci bus devices.

Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> (drivers/pci part)
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sricharan R <sricharan@codeaurora.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2017-04-20 16:31:06 +02:00
Rafael J. Wysocki fdad4e7a87 ACPI / scan: Prefer devices without _HID for _ADR matching
Commit c2a6bbaf0c (ACPI / scan: Prefer devices without _HID/_CID
for _ADR matching) added a list_empty(&adev->pnp.ids) check to
find_child_checks() so as to catch situations in which the ACPI
core attempts to decode _ADR for a device having a _HID too which
is strictly against the spec.  However, it overlooked the fact that
the adev->pnp.ids list for the devices taken into account by
find_child_checks() may contain device IDs set internally by the
kernel, like "LNXVIDEO" (thanks to Zhang Rui for that realization),
and it broke the enumeration of those devices as a result.

To unbreak it, replace the overly coarse grained list_empty()
check with a much more precise check against the pnp.type.platform_id
flag which is only set for devices having a _HID (that's how it
should be done from the start, as having both _ADR and _CID is
actually permitted).

Fixes: c2a6bbaf0c (ACPI / scan: Prefer devices without _HID/_CID for _ADR matching)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=194889
Reported-and-tested-by: Mike <mike@mikewilson.me.uk>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Cc: 4.10+ <stable@vger.kernel.org> # 4.10+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-04-01 00:55:22 +02:00
Hanjun Guo d4f54a1866 ACPI: platform: setup MSI domain for ACPI based platform device
By allowing platform MSI domain to be created on ACPI platforms,
a platform device MSI domain can be set-up when it is probed.

In order to do that, the MSI domain the platform device connects
to should be retrieved, so the iort_get_platform_device_domain() is
introduced to retrieve the domain from the IORT kernel layer.

With the domain retrieved, we need a proper way to set the
domain to platform device.

Given that some platform devices (irqchips) require the MSI irqdomain
to be their interrupt parent domain, the MSI irqdomain should be
determined before platform device is probed but after the platform
device is allocated which means that the code setting up the MSI
irqdomain, ie acpi_configure_pmsi_domain() should be called in
acpi_platform_notify() (that is triggered after adding a device but
before the respective driver is probed) for the platform MSI domain
code set-up path to work properly.

Acked-by: Rafael J. Wysocki <rafael@kernel.org> [for glue.c]
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
[lorenzo.pieralisi@arm.com: rewrote commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Ming Lei <ming.lei@canonical.com>
Tested-by: Wei Xu <xuwei5@hisilicon.com>
Tested-by: Sinan Kaya <okaya@codeaurora.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Tomasz Nowicki <tn@semihalf.com>
2017-03-30 10:20:01 +01:00
Rafael J. Wysocki c2a6bbaf0c ACPI / scan: Prefer devices without _HID/_CID for _ADR matching
The way acpi_find_child_device() works currently is that, if there
are two (or more) devices with the same _ADR value in the same
namespace scope (which is not specifically allowed by the spec and
the OS behavior in that case is not defined), the first one of them
found to be present (with the help of _STA) will be returned.

This covers the majority of cases, but is not sufficient if some of
the devices in question have a _HID (or _CID) returning some valid
ACPI/PNP device IDs (which is disallowed by the spec) and the
ASL writers' expectation appears to be that the OS will match
devices without a valid ACPI/PNP device ID against a given bus
address first.

To cover this special case as well, modify find_child_checks()
to prefer devices without ACPI/PNP device IDs over devices that
have them.

Suggested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
2017-01-02 22:21:59 +01:00
Lorenzo Pieralisi 709f94ff01 ACPI: Drop misplaced acpi_dma_deconfigure() call from acpi_bind_one()
The acpi_bind_one() error return path can be hit either on physical node
allocation failure or if the device being configured is already
associated with an ACPI node and its ACPI companion does not match the
one acpi_bind_one() is setting it up with. In both cases the error
return path is executed before DMA is configured for a device therefore
there is no need to call acpi_dma_deconfigure() on the function error
return path.

Furthermore, if acpi_bind_one() does configure DMA for a device (ie it
successfully executes acpi_dma_configure()) acpi_bind_one() always
completes execution successfully hence there is no need to add an exit
path to deconfigure the DMA set-up (ie by calling acpi_dma_deconfigure()).

Remove the misplaced acpi_dma_deconfigure() in acpi_bind_one() to
reinstate its correct error return path behaviour.

Fixes: d760a1baf2 (ACPI: Implement acpi_dma_configure)
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-12-26 23:15:36 +01:00
Lorenzo Pieralisi d760a1baf2 ACPI: Implement acpi_dma_configure
On DT based systems, the of_dma_configure() API implements DMA
configuration for a given device. On ACPI systems an API equivalent to
of_dma_configure() is missing which implies that it is currently not
possible to set-up DMA operations for devices through the ACPI generic
kernel layer.

This patch fills the gap by introducing acpi_dma_configure/deconfigure()
calls that for now are just wrappers around arch_setup_dma_ops() and
arch_teardown_dma_ops() and also updates ACPI and PCI core code to use
the newly introduced acpi_dma_configure/acpi_dma_deconfigure functions.

Since acpi_dma_configure() is used to configure DMA operations, the
function initializes the dma/coherent_dma masks to sane default values
if the current masks are uninitialized (also to keep the default values
consistent with DT systems) to make sure the device has a complete
default DMA set-up.

The DMA range size passed to arch_setup_dma_ops() is sized according
to the device coherent_dma_mask (starting at address 0x0), mirroring the
DT probing path behaviour when a dma-ranges property is not provided
for the device being probed; this changes the current arch_setup_dma_ops()
call parameters in the ACPI probing case, but since arch_setup_dma_ops()
is a NOP on all architectures but ARM/ARM64 this patch does not change
the current kernel behaviour on them.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> [pci]
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Tomasz Nowicki <tn@semihalf.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: Tomasz Nowicki <tn@semihalf.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Tomasz Nowicki <tn@semihalf.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-11-29 15:57:44 +00:00
Rafael J. Wysocki f2115faaf0 Merge branch 'acpi-pci'
* acpi-pci:
  PCI: ACPI: Add support for PCI device DMA coherency
  PCI: OF: Move of_pci_dma_configure() to pci_dma_configure()
  of/pci: Fix pci_get_host_bridge_device leak
  device property: ACPI: Remove unused DMA APIs
  device property: ACPI: Make use of the new DMA Attribute APIs
  device property: Adding DMA Attribute APIs for Generic Devices
  ACPI: Adding DMA Attribute APIs for ACPI Device
  device property: Introducing enum dev_dma_attr
  ACPI: Honor ACPI _CCA attribute setting

Conflicts:
	drivers/crypto/ccp/ccp-platform.c
2015-11-07 01:30:10 +01:00
Suthikulpanit, Suravee 1831eff876 device property: ACPI: Make use of the new DMA Attribute APIs
Now that we have the new DMA attribute APIs, we can replace the older
acpi_check_dma() and device_dma_is_coherent().

Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-11-07 01:29:22 +01:00
Rami Rosen c33cab60bc ACPI: change init_acpi_device_notify() to return void
This patch changes the type of the return value of the init_acpi_device_notify()
method to be void, as this method never fails and its return value is never
used.

Signed-off-by: Rami Rosen <ramirose@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-09-15 03:01:01 +02:00
Suthikulpanit, Suravee d056267483 ACPI / scan: Parse _CCA and setup device coherency
This patch implements support for ACPI _CCA object, which is introduced in
ACPIv5.1, can be used for specifying device DMA coherency attribute.

The parsing logic traverses device namespace to parse coherency
information, and stores it in acpi_device_flags. Then uses it to call
arch_setup_dma_ops() when creating each device enumerated in DSDT
during ACPI scan.

This patch also introduces acpi_dma_is_coherent(), which provides
an interface for device drivers to check the coherency information
similarly to the of_dma_is_coherent().

Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-06-15 14:40:48 +02:00
Rafael J. Wysocki ca5b74d267 ACPI: Introduce has_acpi_companion()
Now that the ACPI companions of devices are represented by pointers
to struct fwnode_handle, it is not quite efficient to check whether
or not an ACPI companion of a device is present by evaluating the
ACPI_COMPANION() macro.

For this reason, introduce a special static inline routine for that,
has_acpi_companion(), and update the code to use it where applicable.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-03-16 23:49:08 +01:00
Rafael J. Wysocki 9cb32acf09 ACPI / scan: Add bind/unbind callbacks to struct acpi_scan_handler
In some cases it may be necessary to perform certain setup/cleanup
operations on a device object representing a physical device after
it has been associated with an ACPI companion by acpi_bind_one() or
before disassociating it from that companion by acpi_unbind_one(),
respectively.  If there is a struct acpi_bus_type object for the
given device's bus type, the .setup()/.cleanup() callbacks from there
are executed for these purposes.  However, an analogous mechanism will
be necessary for devices whose bus types don't have corresponding
struct acpi_bus_type objects and that have specific ACPI scan handlers.

For those devices, add new .bind() and .unbind() callbacks to struct
acpi_scan_handler that will be executed by acpi_platform_notify()
right after the given device has been associated with an ACPI
comapnion and by acpi_platform_notify_remove() right before calling
acpi_unbind_one() for that device, respectively.

To make that work for scan handlers registering new devices in their
.attach() callbacks, modify acpi_scan_attach_handler() to set the
ACPI device object's handler field before calling .attach() from the
scan handler at hand.

This changeset includes a fix from Mika Westerberg.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-11 00:35:46 +01:00
Rafael J. Wysocki bfecc2b3e3 ACPI / bind: Move acpi_get_child() to drivers/ide/ide-acpi.c
Since drivers/ide/ide-acpi.c is the only remaining user of
acpi_get_child(), move that function into that file as a static
routine.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-12-07 01:05:50 +01:00
Rafael J. Wysocki 24dee1fc99 ACPI / bind: Pass struct acpi_device pointer to acpi_bind_one()
There is no reason to pass an ACPI handle to acpi_bind_one() instead
of a struct acpi_device pointer to the target device object, so
modify that function to take a struct acpi_device pointer as its
second argument and update all code depending on it accordingly.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Lan Tianyu <tianyu.lan@intel.com> # for USB/ACPI
2013-12-07 01:05:50 +01:00
Rafael J. Wysocki e3f02c5228 ACPI / bind: Rework struct acpi_bus_type
Replace the .find_device function pointer in struct acpi_bus_type
with a new one, .find_companion, that is supposed to point to a
function returning struct acpi_device pointer (instead of an int)
and takes one argument (instead of two).  This way the role of
this callback is more clear and the implementation of it can
be more straightforward.

Update all of the users of struct acpi_bus_type (PCI, PNP/ACPI and
USB) to reflect the structure change.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Lan Tianyu <tianyu.lan@intel.com> # for USB/ACPI
2013-12-07 01:05:50 +01:00
Rafael J. Wysocki 9c5ad36d98 ACPI / bind: Redefine acpi_preset_companion()
Modify acpi_preset_companion() to take a struct acpi_device pointer
instead of an ACPI handle as its second argument and redefine it as
a static inline wrapper around ACPI_COMPANION_SET() passing the
return value of acpi_find_child_device() directly as the second
argument to it.  Update its users to pass struct acpi_device
pointers instead of ACPI handles to it.

This allows some unnecessary acpi_bus_get_device() calls to be
avoided.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
Tested-by: Aaron Lu <aaron.lu@intel.com> # for ATA binding
2013-12-07 01:05:49 +01:00
Rafael J. Wysocki 11dcc75dba ACPI / bind: Redefine acpi_get_child()
Since acpi_get_child() is the only user of acpi_find_child() now,
drop the static inline definition of the former and redefine the
latter as new acpi_get_child().

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
Tested-by: Aaron Lu <aaron.lu@intel.com> # for ATA binding
2013-12-07 01:05:49 +01:00
Rafael J. Wysocki 5ce79d2013 PCI / ACPI: Use acpi_find_child_device() for child devices lookup
It is much more efficient to use acpi_find_child_device()
for child devices lookup in acpi_pci_find_device() and pass
ACPI_COMPANION(dev->parent) to it directly instead of obtaining
ACPI_HANDLE() of ACPI_COMPANION(dev->parent) and passing it to
acpi_find_child() which has to run acpi_bus_get_device() to
obtain ACPI_COMPANION(dev->parent) from that again.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
2013-12-07 01:05:48 +01:00
Rafael J. Wysocki d9fef0c4d2 ACPI / bind: Simplify child device lookups
Now that we create a struct acpi_device object for every ACPI
namespace node representing a device, it is not necessary to
use acpi_walk_namespace() for child device lookup in
acpi_find_child() any more.  Instead, we can simply walk the
list of children of the given struct acpi_device object and
return the matching one (or the one which is the best match if
there are more of them).  The checks done during the matching
loop can be simplified too so that the secondary namespace walks
in find_child_checks() are not necessary any more.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
2013-12-07 01:05:48 +01:00
Rafael J. Wysocki a104b4d467 ACPI / bind: Use (put|get)_device() on ACPI device objects too
When associating a "physical" device with an ACPI device object
acpi_bind_one() only uses get_device() to increment the reference
counter of the former, but there is no reason not to do that with
the latter too.  Among other things, that may help to avoid
use-after-free when an ACPI device object is freed without calling
acpi_unbind_one() for all "physical" devices associated with it
(that only can happen in buggy code, but then it's better if the
kernel doesn't crash as a result of a bug).

For this reason, modify acpi_bind_one() to apply get_device() to
the ACPI device object too and update acpi_unbind_one() to drop
that reference using put_device() as appropriate.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Lan Tianyu <tianyu.lan@intel.com>
2013-11-14 23:18:32 +01:00
Rafael J. Wysocki 7b1998116b ACPI / driver core: Store an ACPI device pointer in struct acpi_dev_node
Modify struct acpi_dev_node to contain a pointer to struct acpi_device
associated with the given device object (that is, its ACPI companion
device) instead of an ACPI handle corresponding to it.  Introduce two
new macros for manipulating that pointer in a CONFIG_ACPI-safe way,
ACPI_COMPANION() and ACPI_COMPANION_SET(), and rework the
ACPI_HANDLE() macro to take the above changes into account.
Drop the ACPI_HANDLE_SET() macro entirely and rework its users to
use ACPI_COMPANION_SET() instead.  For some of them who used to
pass the result of acpi_get_child() directly to ACPI_HANDLE_SET()
introduce a helper routine acpi_preset_companion() doing an
equivalent thing.

The main motivation for doing this is that there are things
represented by struct acpi_device objects that don't have valid
ACPI handles (so called fixed ACPI hardware features, such as
power and sleep buttons) and we would like to create platform
device objects for them and "glue" them to their ACPI companions
in the usual way (which currently is impossible due to the
lack of valid ACPI handles).  However, there are more reasons
why it may be useful.

First, struct acpi_device pointers allow of much better type checking
than void pointers which are ACPI handles, so it should be more
difficult to write buggy code using modified struct acpi_dev_node
and the new macros.  Second, the change should help to reduce (over
time) the number of places in which the result of ACPI_HANDLE() is
passed to acpi_bus_get_device() in order to obtain a pointer to the
struct acpi_device associated with the given "physical" device,
because now that pointer is returned by ACPI_COMPANION() directly.
Finally, the change should make it easier to write generic code that
will build both for CONFIG_ACPI set and unset without adding explicit
compiler directives to it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com> # on Haswell
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com> # for ATA and SDIO part
2013-11-14 23:14:43 +01:00
Rafael J. Wysocki 11b88ee275 ACPI / bind: Prefer device objects with _STA to those without it
As reported at https://bugzilla.kernel.org/show_bug.cgi?id=60829,
there still are cases in which do_find_child() doesn't choose the
ACPI device object it is "expected" to choose if there are more such
objects matching one PCI device present.  This particular problem may
be worked around by making do_find_child() return device obejcts witn
_STA whose result indicates that the device is enabled before device
objects without _STA if there's more than one device object to choose
from.

This change doesn't affect the case in which there's only one
matching ACPI device object per PCI device.

References: https://bugzilla.kernel.org/show_bug.cgi?id=60829
Reported-by: Peter Wu <lekensteyn@gmail.com>
Tested-by: Felix Lisczyk <felix.lisczyk@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-09 23:07:47 +02:00
Rafael J. Wysocki 464c114717 ACPI: Print diagnostic messages if device links cannot be created
Although the device links created by acpi_bind_one() are not
essential from the kernel functionality point of view, user space
may be confused when they are missing, so print diagnostic messages
to the kernel log if they can't be created.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
2013-08-09 00:54:52 +02:00
Rafael J. Wysocki 3342c753bd ACPI: Drop unnecessary label from acpi_bind_one()
The out_free label in acpi_bind_one() is only jumped to from one
place, so in fact it is not necessary, because the code below it
can be moved to that place directly.  Move that code and drop the
label.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
2013-08-09 00:52:21 +02:00
Rafael J. Wysocki 38e88839ef ACPI: Clean up error code path in acpi_unbind_one()
The error code path in acpi_unbind_one() is unnecessarily complicated
(in particular, the err label is not really necessary) and the error
message printed by it is inaccurate (there's nothing called
'acpi_handle' in that function), so clean up those things.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
2013-08-07 23:41:48 +02:00
Rafael J. Wysocki 3e3327837c ACPI: Use list_for_each_entry() in acpi_unbind_one()
Since acpi_unbind_one() walks physical_node_list under the ACPI
device object's physical_node_lock mutex and the walk may be
terminated as soon as the matching entry has been found, it is
not necessary to use list_for_each_safe() for that walk, so use
list_for_each_entry() instead and make the code slightly more
straightforward.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
2013-08-07 23:41:47 +02:00
Rafael J. Wysocki f501b6ec29 ACPI: acpi_bind_one()/acpi_unbind_one() whitespace cleanups
Clean up some inconsistent use of whitespace in acpi_bind_one() and
acpi_unbind_one().

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
2013-08-07 23:41:47 +02:00
Rafael J. Wysocki 4005520648 ACPI: Create symlinks in acpi_bind_one() under physical_node_lock
Put the creation of symlinks in acpi_bind_one() under the
physical_node_lock mutex of the given ACPI device object, because
that is part of the binding operation logically (those links are
already removed under that mutex too).

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
2013-08-07 23:41:47 +02:00
Rafael J. Wysocki bdbdbf9108 ACPI: Reduce acpi_bind_one()/acpi_unbind_one() code duplication
Move some duplicated code from acpi_bind_one() and acpi_unbind_one()
into a separate function and make that function use snprintf()
instead of sprintf() for extra safety.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
2013-08-07 23:41:46 +02:00
Rafael J. Wysocki 3fe444ad7e ACPI: Do not fail acpi_bind_one() if device is already bound correctly
Modify acpi_bind_one() so that it doesn't fail if the device
represented by its first argument has already been bound to the
given ACPI handle (second argument), because that is not a good
enough reason for returning an error code.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lan Tianyu <tianyu.lan@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
2013-08-07 23:41:46 +02:00
Rafael J. Wysocki 60f75b8e97 ACPI: Try harder to resolve _ADR collisions for bridges
In theory, under a given ACPI namespace node there should be only
one child device object with _ADR whose value matches a given bus
address exactly.  In practice, however, there are systems in which
multiple child device objects under a given parent have _ADR matching
exactly the same address.  In those cases we use _STA to determine
which of the multiple matching devices is enabled, since some systems
are known to indicate which ACPI device object to associate with the
given physical (usually PCI) device this way.

Unfortunately, as it turns out, there are systems in which many
device objects under the same parent have _ADR matching exactly the
same bus address and none of them has _STA, in which case they all
should be regarded as enabled according to the spec.  Still, if
those device objects are supposed to represent bridges (e.g. this
is the case for device objects corresponding to PCIe ports), we can
try harder and skip the ones that have no child device objects in the
ACPI namespace.  With luck, we can avoid using device objects that we
are not expected to use this way.

Although this only works for bridges whose children also have ACPI
namespace representation, it is sufficient to address graphics
adapter detection issues on some systems, so rework the code finding
a matching device ACPI handle for a given bus address to implement
this idea.

Introduce a new function, acpi_find_child(), taking three arguments:
the ACPI handle of the device's parent, a bus address suitable for
the device's bus type and a bool indicating if the device is a
bridge and make it work as outlined above.  Reimplement the function
currently used for this purpose, acpi_get_child(), as a call to
acpi_find_child() with the last argument set to 'false' and make
the PCI subsystem use acpi_find_child() with the bridge information
passed as the last argument to it.  [Lan Tianyu notices that it is
not sufficient to use pci_is_bridge() for that, because the device's
subordinate pointer hasn't been set yet at this point, so use
hdr_type instead.]

This change fixes a regression introduced inadvertently by commit
33f767d (ACPI: Rework acpi_get_child() to be more efficient) which
overlooked the fact that for acpi_walk_namespace() "post-order" means
"after all children have been visited" rather than "on the way back",
so for device objects without children and for namespace walks of
depth 1, as in the acpi_get_child() case, the "post-order" callbacks
ordering is actually the same as the ordering of "pre-order" ones.
Since that commit changed the namespace walk in acpi_get_child() to
terminate after finding the first matching object instead of going
through all of them and returning the last one, it effectively
changed the result returned by that function in some rare cases and
that led to problems (the switch from a "pre-order" to a "post-order"
callback was supposed to prevent that from happening, but it was
ineffective).

As it turns out, the systems where the change made by commit
33f767d actually matters are those where there are multiple ACPI
device objects representing the same PCIe port (which effectively
is a bridge).  Moreover, only one of them, and the one we are
expected to use, has child device objects in the ACPI namespace,
so the regression can be addressed as described above.

References: https://bugzilla.kernel.org/show_bug.cgi?id=60561
Reported-by: Peter Wu <lekensteyn@gmail.com>
Tested-by: Vladimir Lalov <mail@vlalov.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: 3.9+ <stable@vger.kernel.org> # 3.9+
2013-08-07 22:55:00 +02:00