summaryrefslogtreecommitdiff
path: root/kernel/irq/irqdomain.c
AgeCommit message (Collapse)Author
2023-02-13irqdomain: Drop revmap mutexJohan Hovold
The revmap mutex is essentially only used to maintain the integrity of the radix tree during updates (lookups use RCU). As the global irq_domain_mutex is now held in all paths that update the revmap structures there is strictly no longer any need for the dedicated mutex, which can be removed. Drop the revmap mutex and add lockdep assertions to the revmap helpers to make sure that the global lock is always held when updating the revmap. Tested-by: Hsin-Yi Wang <hsinyi@chromium.org> Tested-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com> Signed-off-by: Johan Hovold <johan+linaro@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230213104302.17307-9-johan+linaro@kernel.org
2023-02-13irqdomain: Fix domain registration raceMarc Zyngier
Hierarchical domains created using irq_domain_create_hierarchy() are currently added to the domain list before having been fully initialised. This specifically means that a racing allocation request might fail to allocate irq data for the inner domains of a hierarchy in case the parent domain pointer has not yet been set up. Note that this is not really any issue for irqchip drivers that are registered early (e.g. via IRQCHIP_DECLARE() or IRQCHIP_ACPI_DECLARE()) but could potentially cause trouble with drivers that are registered later (e.g. modular drivers using IRQCHIP_PLATFORM_DRIVER_BEGIN(), gpiochip drivers, etc.). Fixes: afb7da83b9f4 ("irqdomain: Introduce helper function irq_domain_add_hierarchy()") Cc: stable@vger.kernel.org # 3.19 Signed-off-by: Marc Zyngier <maz@kernel.org> [ johan: add commit message ] Signed-off-by: Johan Hovold <johan+linaro@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230213104302.17307-8-johan+linaro@kernel.org
2023-02-13irqdomain: Fix mapping-creation raceJohan Hovold
Parallel probing of devices that share interrupts (e.g. when a driver uses asynchronous probing) can currently result in two mappings for the same hardware interrupt to be created due to missing serialisation. Make sure to hold the irq_domain_mutex when creating mappings so that looking for an existing mapping before creating a new one is done atomically. Fixes: 765230b5f084 ("driver-core: add asynchronous probing support for drivers") Fixes: b62b2cf5759b ("irqdomain: Fix handling of type settings for existing mappings") Link: https://lore.kernel.org/r/YuJXMHoT4ijUxnRb@hovoldconsulting.com Cc: stable@vger.kernel.org # 4.8 Cc: Dmitry Torokhov <dtor@chromium.org> Cc: Jon Hunter <jonathanh@nvidia.com> Tested-by: Hsin-Yi Wang <hsinyi@chromium.org> Tested-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com> Signed-off-by: Johan Hovold <johan+linaro@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230213104302.17307-7-johan+linaro@kernel.org
2023-02-13irqdomain: Refactor __irq_domain_alloc_irqs()Johan Hovold
Refactor __irq_domain_alloc_irqs() so that it can be called internally while holding the irq_domain_mutex. This will be used to fix a shared-interrupt mapping race, hence the Fixes tag. Fixes: b62b2cf5759b ("irqdomain: Fix handling of type settings for existing mappings") Cc: stable@vger.kernel.org # 4.8 Tested-by: Hsin-Yi Wang <hsinyi@chromium.org> Tested-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com> Signed-off-by: Johan Hovold <johan+linaro@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230213104302.17307-6-johan+linaro@kernel.org
2023-02-13irqdomain: Look for existing mapping only onceJohan Hovold
Avoid looking for an existing mapping twice when creating a new mapping using irq_create_fwspec_mapping() by factoring out the actual allocation which is shared with irq_create_mapping_affinity(). The new helper function will also be used to fix a shared-interrupt mapping race, hence the Fixes tag. Fixes: b62b2cf5759b ("irqdomain: Fix handling of type settings for existing mappings") Cc: stable@vger.kernel.org # 4.8 Tested-by: Hsin-Yi Wang <hsinyi@chromium.org> Tested-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com> Signed-off-by: Johan Hovold <johan+linaro@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230213104302.17307-5-johan+linaro@kernel.org
2023-02-13irqdomain: Drop bogus fwspec-mapping error handlingJohan Hovold
In case a newly allocated IRQ ever ends up not having any associated struct irq_data it would not even be possible to dispose the mapping. Replace the bogus disposal with a WARN_ON(). This will also be used to fix a shared-interrupt mapping race, hence the CC-stable tag. Fixes: 1e2a7d78499e ("irqdomain: Don't set type when mapping an IRQ") Cc: stable@vger.kernel.org # 4.8 Tested-by: Hsin-Yi Wang <hsinyi@chromium.org> Tested-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com> Signed-off-by: Johan Hovold <johan+linaro@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230213104302.17307-4-johan+linaro@kernel.org
2023-02-13irqdomain: Fix disassociation raceJohan Hovold
The global irq_domain_mutex is held when mapping interrupts from non-hierarchical domains but currently not when disposing them. This specifically means that updates of the domain mapcount is racy (currently only used for statistics in debugfs). Make sure to hold the global irq_domain_mutex also when disposing mappings from non-hierarchical domains. Fixes: 9dc6be3d4193 ("genirq/irqdomain: Add map counter") Cc: stable@vger.kernel.org # 4.13 Tested-by: Hsin-Yi Wang <hsinyi@chromium.org> Tested-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com> Signed-off-by: Johan Hovold <johan+linaro@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230213104302.17307-3-johan+linaro@kernel.org
2023-02-13irqdomain: Fix association raceJohan Hovold
The sanity check for an already mapped virq is done outside of the irq_domain_mutex-protected section which means that an (unlikely) racing association may not be detected. Fix this by factoring out the association implementation, which will also be used in a follow-on change to fix a shared-interrupt mapping race. Fixes: ddaf144c61da ("irqdomain: Refactor irq_domain_associate_many()") Cc: stable@vger.kernel.org # 3.11 Tested-by: Hsin-Yi Wang <hsinyi@chromium.org> Tested-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com> Signed-off-by: Johan Hovold <johan+linaro@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230213104302.17307-2-johan+linaro@kernel.org
2023-02-05Merge tag 'char-misc-6.2-rc7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc driver fixes from Greg KH: "Here are a number of small char/misc/whatever driver fixes. They include: - IIO driver fixes for some reported problems - nvmem driver fixes - fpga driver fixes - debugfs memory leak fix in the hv_balloon and irqdomain code (irqdomain change was acked by the maintainer) All have been in linux-next with no reported problems" * tag 'char-misc-6.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (33 commits) kernel/irq/irqdomain.c: fix memory leak with using debugfs_lookup() HV: hv_balloon: fix memory leak with using debugfs_lookup() nvmem: qcom-spmi-sdam: fix module autoloading nvmem: core: fix return value nvmem: core: fix cell removal on error nvmem: core: fix device node refcounting nvmem: core: fix registration vs use race nvmem: core: fix cleanup after dev_set_name() nvmem: core: remove nvmem_config wp_gpio nvmem: core: initialise nvmem->id early nvmem: sunxi_sid: Always use 32-bit MMIO reads nvmem: brcm_nvram: Add check for kzalloc iio: imu: fxos8700: fix MAGN sensor scale and unit iio: imu: fxos8700: remove definition FXOS8700_CTRL_ODR_MIN iio: imu: fxos8700: fix failed initialization ODR mode assignment iio: imu: fxos8700: fix incorrect ODR mode readback iio: light: cm32181: Fix PM support on system with 2 I2C resources iio: hid: fix the retval in gyro_3d_capture_sample iio: hid: fix the retval in accel_3d_capture_sample iio: imu: st_lsm6dsx: fix build when CONFIG_IIO_TRIGGERED_BUFFER=m ...
2023-02-03kernel/irq/irqdomain.c: fix memory leak with using debugfs_lookup()Greg Kroah-Hartman
When calling debugfs_lookup() the result must have dput() called on it, otherwise the memory will leak over time. To make things simpler, just call debugfs_lookup_and_remove() instead which handles all of the logic at once. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable <stable@kernel.org> Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230202151554.2310273-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-17genirq/msi: Free the fwnode created by msi_create_device_irq_domain()Jason Gunthorpe
msi_create_device_irq_domain() creates a firmware node for the new domain, which is never freed. kmemleak reports: unreferenced object 0xffff888120ba9a00 (size 96): comm "systemd-modules", pid 221, jiffies 4294893411 (age 635.732s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 e0 19 8b 83 ff ff ff ff ................ 00 00 00 00 00 00 00 00 18 9a ba 20 81 88 ff ff ........... .... backtrace: [<000000008cdbc98d>] __irq_domain_alloc_fwnode+0x51/0x2b0 [<00000000c57acf9d>] msi_create_device_irq_domain+0x283/0x670 [<000000009b567982>] __pci_enable_msix_range+0x49e/0xdb0 [<0000000077cc1445>] pci_alloc_irq_vectors_affinity+0x11f/0x1c0 [<00000000532e9ef5>] mlx5_irq_table_create+0x24c/0x940 [mlx5_core] [<00000000fabd2b80>] mlx5_load+0x1fa/0x680 [mlx5_core] [<000000006bb22ae4>] mlx5_init_one+0x485/0x670 [mlx5_core] [<00000000eaa5e1ad>] probe_one+0x4c2/0x720 [mlx5_core] [<00000000df8efb43>] local_pci_probe+0xd6/0x170 [<0000000085cb9924>] pci_device_probe+0x231/0x6e0 Use the proper free operation for the firmware wnode so the name is freed during error unwind of msi_create_device_irq_domain() and also free the node in msi_remove_device_irq_domain() if it was automatically allocated. To avoid extra NULL pointer checks make irq_domain_free_fwnode() tolerant of NULL. Fixes: 27a6dea3ebaa ("genirq/msi: Provide msi_create/free_device_irq_domain()") Reported-by: Omri Barazi <obarazi@nvidia.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Kalle Valo <kvalo@kernel.org> Tested-by: Leon Romanovsky <leonro@nvidia.com> Link: https://lore.kernel.org/r/0-v2-24af6665e2da+c9-msi_leak_jgg@nvidia.com
2023-01-11genirq/irqdomain: Remove unused irq_domain_check_msi_remap() codeJason Gunthorpe
After converting the users of irq_domain_check_msi_remap() it and the helpers are no longer needed. The new version does not require all the #ifdef helpers and inlines because CONFIG_GENERIC_MSI_IRQ always requires CONFIG_IRQ_DOMAIN and IRQ_DOMAIN_HIERARCHY. Link: https://lore.kernel.org/r/5-v3-3313bb5dd3a3+10f11-secure_msi_jgg@nvidia.com Tested-by: Matthew Rosato <mjrosato@linux.ibm.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2022-07-19irqdomain: Use hwirq_max instead of revmap_size for NOMAP domainsXu Qiang
NOMAP irq domains use the revmap_size field to indicate the maximum hwirq number the domain accepts. This is a bit confusing as revmap_size is usually used to indicate the size of the revmap array, which a NOMAP domain doesn't have. Instead, use the hwirq_max field which has the correct semantics, and keep revmap_size to 0 for a NOMAP domain. Signed-off-by: Xu Qiang <xuqiang36@huawei.com> [maz: commit message] Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220719063641.56541-3-xuqiang36@huawei.com
2022-07-19irqdomain: Report irq number for NOMAP domainsXu Qiang
When using a NOMAP domain, __irq_resolve_mapping() doesn't store the Linux IRQ number at the address optionally provided by the caller. While this isn't a huge deal (the returned value is guaranteed to the hwirq that was passed as a parameter), let's honour the letter of the API by writing the expected value. Fixes: d22558dd0a6c (“irqdomain: Introduce irq_resolve_mapping()”) Signed-off-by: Xu Qiang <xuqiang36@huawei.com> [maz: commit message] Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220719063641.56541-2-xuqiang36@huawei.com
2022-02-15irqdomain: Let irq_domain_set_{info,hwirq_and_chip} take a const irq_chipMarc Zyngier
In order to let a const irqchip be fed to the irqchip layer, adjust the various prototypes. An extra cast in irq_domain_set_hwirq_and_chip() is required to avoid a warning. Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20220209162607.1118325-2-maz@kernel.org
2021-11-06Merge tag 'pci-v5.16-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull pci updates from Bjorn Helgaas: "Enumeration: - Conserve IRQs by setting up portdrv IRQs only when there are users (Jan Kiszka) - Rework and simplify _OSC negotiation for control of PCIe features (Joerg Roedel) - Remove struct pci_dev.driver pointer since it's redundant with the struct device.driver pointer (Uwe Kleine-König) Resource management: - Coalesce contiguous host bridge apertures from _CRS to accommodate BARs that cover more than one aperture (Kai-Heng Feng) Sysfs: - Check CAP_SYS_ADMIN before parsing user input (Krzysztof Wilczyński) - Return -EINVAL consistently from "store" functions (Krzysztof Wilczyński) - Use sysfs_emit() in endpoint "show" functions to avoid buffer overruns (Kunihiko Hayashi) PCIe native device hotplug: - Ignore Link Down/Up caused by resets during error recovery so endpoint drivers can remain bound to the device (Lukas Wunner) Virtualization: - Avoid bus resets on Atheros QCA6174, where they hang the device (Ingmar Klein) - Work around Pericom PI7C9X2G switch packet drop erratum by using store and forward mode instead of cut-through (Nathan Rossi) - Avoid trying to enable AtomicOps on VFs; the PF setting applies to all VFs (Selvin Xavier) MSI: - Document that /sys/bus/pci/devices/.../irq contains the legacy INTx interrupt or the IRQ of the first MSI (not MSI-X) vector (Barry Song) VPD: - Add pci_read_vpd_any() and pci_write_vpd_any() to access anywhere in the possible VPD space; use these to simplify the cxgb3 driver (Heiner Kallweit) Peer-to-peer DMA: - Add (not subtract) the bus offset when calculating DMA address (Wang Lu) ASPM: - Re-enable LTR at Downstream Ports so they don't report Unsupported Requests when reset or hot-added devices send LTR messages (Mingchuang Qiao) Apple PCIe controller driver: - Add driver for Apple M1 PCIe controller (Alyssa Rosenzweig, Marc Zyngier) Cadence PCIe controller driver: - Return success when probe succeeds instead of falling into error path (Li Chen) HiSilicon Kirin PCIe controller driver: - Reorganize PHY logic and add support for external PHY drivers (Mauro Carvalho Chehab) - Support PERST# GPIOs for HiKey970 external PEX 8606 bridge (Mauro Carvalho Chehab) - Add Kirin 970 support (Mauro Carvalho Chehab) - Make driver removable (Mauro Carvalho Chehab) Intel VMD host bridge driver: - If IOMMU supports interrupt remapping, leave VMD MSI-X remapping enabled (Adrian Huang) - Number each controller so we can tell them apart in /proc/interrupts (Chunguang Xu) - Avoid building on UML because VMD depends on x86 bare metal APIs (Johannes Berg) Marvell Aardvark PCIe controller driver: - Define macros for PCI_EXP_DEVCTL_PAYLOAD_* (Pali Rohár) - Set Max Payload Size to 512 bytes per Marvell spec (Pali Rohár) - Downgrade PIO Response Status messages to debug level (Marek Behún) - Preserve CRS SV (Config Request Retry Software Visibility) bit in emulated Root Control register (Pali Rohár) - Fix issue in configuring reference clock (Pali Rohár) - Don't clear status bits for masked interrupts (Pali Rohár) - Don't mask unused interrupts (Pali Rohár) - Avoid code repetition in advk_pcie_rd_conf() (Marek Behún) - Retry config accesses on CRS response (Pali Rohár) - Simplify emulated Root Capabilities initialization (Pali Rohár) - Fix several link training issues (Pali Rohár) - Fix link-up checking via LTSSM (Pali Rohár) - Fix reporting of Data Link Layer Link Active (Pali Rohár) - Fix emulation of W1C bits (Marek Behún) - Fix MSI domain .alloc() method to return zero on success (Marek Behún) - Read entire 16-bit MSI vector in MSI handler, not just low 8 bits (Marek Behún) - Clear Root Port I/O Space, Memory Space, and Bus Master Enable bits at startup; PCI core will set those as necessary (Pali Rohár) - When operating as a Root Port, set class code to "PCI Bridge" instead of the default "Mass Storage Controller" (Pali Rohár) - Add emulation for PCI_BRIDGE_CTL_BUS_RESET since aardvark doesn't implement this per spec (Pali Rohár) - Add emulation of option ROM BAR since aardvark doesn't implement this per spec (Pali Rohár) MediaTek MT7621 PCIe controller driver: - Add MediaTek MT7621 PCIe host controller driver and DT binding (Sergio Paracuellos) Qualcomm PCIe controller driver: - Add SC8180x compatible string (Bjorn Andersson) - Add endpoint controller driver and DT binding (Manivannan Sadhasivam) - Restructure to use of_device_get_match_data() (Prasad Malisetty) - Add SC7280-specific pcie_1_pipe_clk_src handling (Prasad Malisetty) Renesas R-Car PCIe controller driver: - Remove unnecessary includes (Geert Uytterhoeven) Rockchip DesignWare PCIe controller driver: - Add DT binding (Simon Xue) Socionext UniPhier Pro5 controller driver: - Serialize INTx masking/unmasking (Kunihiko Hayashi) Synopsys DesignWare PCIe controller driver: - Run dwc .host_init() method before registering MSI interrupt handler so we can deal with pending interrupts left by bootloader (Bjorn Andersson) - Clean up Kconfig dependencies (Andy Shevchenko) - Export symbols to allow more modular drivers (Luca Ceresoli) TI DRA7xx PCIe controller driver: - Allow host and endpoint drivers to be modules (Luca Ceresoli) - Enable external clock if present (Luca Ceresoli) TI J721E PCIe driver: - Disable PHY when probe fails after initializing it (Christophe JAILLET) MicroSemi Switchtec management driver: - Return error to application when command execution fails because an out-of-band reset has cleared the device BARs, Memory Space Enable, etc (Kelvin Cao) - Fix MRPC error status handling issue (Kelvin Cao) - Mask out other bits when reading of management VEP instance ID (Kelvin Cao) - Return EOPNOTSUPP instead of ENOTSUPP from sysfs show functions (Kelvin Cao) - Add check of event support (Logan Gunthorpe) Miscellaneous: - Remove unused pci_pool wrappers, which have been replaced by dma_pool (Cai Huoqing) - Use 'unsigned int' instead of bare 'unsigned' (Krzysztof Wilczyński) - Use kstrtobool() directly, sans strtobool() wrapper (Krzysztof Wilczyński) - Fix some sscanf(), sprintf() format mismatches (Krzysztof Wilczyński) - Update PCI subsystem information in MAINTAINERS (Krzysztof Wilczyński) - Correct some misspellings (Krzysztof Wilczyński)" * tag 'pci-v5.16-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (137 commits) PCI: Add ACS quirk for Pericom PI7C9X2G switches PCI: apple: Configure RID to SID mapper on device addition iommu/dart: Exclude MSI doorbell from PCIe device IOVA range PCI: apple: Implement MSI support PCI: apple: Add INTx and per-port interrupt support PCI: kirin: Allow removing the driver PCI: kirin: De-init the dwc driver PCI: kirin: Disable clkreq during poweroff sequence PCI: kirin: Move the power-off code to a common routine PCI: kirin: Add power_off support for Kirin 960 PHY PCI: kirin: Allow building it as a module PCI: kirin: Add MODULE_* macros PCI: kirin: Add Kirin 970 compatible PCI: kirin: Support PERST# GPIOs for HiKey970 external PEX 8606 bridge PCI: apple: Set up reference clocks when probing PCI: apple: Add initial hardware bring-up PCI: of: Allow matching of an interrupt-map local to a PCI device of/irq: Allow matching of an interrupt-map local to an interrupt controller irqdomain: Make of_phandle_args_to_fwspec() generally available PCI: Do not enable AtomicOps on VFs ...
2021-11-04PCI: apple: Add INTx and per-port interrupt supportMarc Zyngier
Add support for the per-port interrupt controller that deals with both INTx signalling and management interrupts. This allows the Link-up/Link-down interrupts to be wired, allowing the bring-up to be synchronised (and provide debug information). The framework can further be used to handle the rest of the per port events if and when necessary. Likewise, INTx signalling is implemented so that end-points can actually be used. Link: https://lore.kernel.org/r/20210929163847.2807812-7-maz@kernel.org Link: https://lore.kernel.org/r/20211004150552.3844830-1-maz@kernel.org Tested-by: Alyssa Rosenzweig <alyssa@rosenzweig.io> Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2021-11-04irqdomain: Make of_phandle_args_to_fwspec() generally availableMarc Zyngier
of_phandle_args_to_fwspec() can be generally useful to code extracting a DT of_phandle and using an irq_fwspec to use the hierarchical irqdomain API. Make it visible to the rest of the kernel, including modules. Link: https://lore.kernel.org/r/20210929163847.2807812-2-maz@kernel.org Tested-by: Alyssa Rosenzweig <alyssa@rosenzweig.io> Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2021-09-24Merge tag 'irqchip-fixes-5.15-1' of ↵Thomas Gleixner
git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/urgent Pull irqchip fixes from Marc Zyngier: - Work around a bad GIC integration on a Renesas platform, where the interconnect cannot deal with byte-sized MMIO accesses - Cleanup another Renesas driver abusing the comma operator - Fix a potential GICv4 memory leak on an error path - Make the type of 'size' consistent with the rest of the code in __irq_domain_add() - Fix a regression in the Armada 370-XP IPI path - Fix the build for the obviously unloved goldfish-pic - Some documentation fixes Link: https://lore.kernel.org/r/20210924090933.2766857-1-maz@kernel.org
2021-09-22irqdomain: Change the type of 'size' in __irq_domain_add() to be consistentBixuan Cui
The 'size' is used in struct_size(domain, revmap, size) and its input parameter type is 'size_t'(unsigned int). Changing the size to 'unsigned int' to make the type consistent. Signed-off-by: Bixuan Cui <cuibixuan@huawei.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20210916025203.44841-1-cuibixuan@huawei.com
2021-09-03Merge tag 'powerpc-5.15-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Convert pseries & powernv to use MSI IRQ domains. - Rework the pseries CPU numbering so that CPUs that are removed, and later re-added, are given a CPU number on the same node as previously, when possible. - Add support for a new more flexible device-tree format for specifying NUMA distances. - Convert powerpc to GENERIC_PTDUMP. - Retire sbc8548 and sbc8641d board support. - Various other small features and fixes. Thanks to Alexey Kardashevskiy, Aneesh Kumar K.V, Anton Blanchard, Cédric Le Goater, Christophe Leroy, Emmanuel Gil Peyrot, Fabiano Rosas, Fangrui Song, Finn Thain, Gautham R. Shenoy, Hari Bathini, Joel Stanley, Jordan Niethe, Kajol Jain, Laurent Dufour, Leonardo Bras, Lukas Bulwahn, Marc Zyngier, Masahiro Yamada, Michal Suchanek, Nathan Chancellor, Nicholas Piggin, Parth Shah, Paul Gortmaker, Pratik R. Sampat, Randy Dunlap, Sebastian Andrzej Siewior, Srikar Dronamraju, Wan Jiabing, Xiongwei Song, and Zheng Yongjun. * tag 'powerpc-5.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (154 commits) powerpc/bug: Cast to unsigned long before passing to inline asm powerpc/ptdump: Fix generic ptdump for 64-bit KVM: PPC: Fix clearing never mapped TCEs in realmode powerpc/pseries/iommu: Rename "direct window" to "dma window" powerpc/pseries/iommu: Make use of DDW for indirect mapping powerpc/pseries/iommu: Find existing DDW with given property name powerpc/pseries/iommu: Update remove_dma_window() to accept property name powerpc/pseries/iommu: Reorganize iommu_table_setparms*() with new helper powerpc/pseries/iommu: Add ddw_property_create() and refactor enable_ddw() powerpc/pseries/iommu: Allow DDW windows starting at 0x00 powerpc/pseries/iommu: Add ddw_list_new_entry() helper powerpc/pseries/iommu: Add iommu_pseries_alloc_table() helper powerpc/kernel/iommu: Add new iommu_table_in_use() helper powerpc/pseries/iommu: Replace hard-coded page shift powerpc/numa: Update cpu_cpu_map on CPU online/offline powerpc/numa: Print debug statements only when required powerpc/numa: convert printk to pr_xxx powerpc/numa: Drop dbg in favour of pr_debug powerpc/smp: Enable CACHE domain for shared processor powerpc/smp: Update cpu_core_map on all PowerPc systems ...
2021-08-23irqdomain: Export irq_domain_disconnect_hierarchy()Maulik Shah
Export irq_domain_disconnect_hierarchy() so irqchip module drivers can use it. Signed-off-by: Maulik Shah <mkshah@codeaurora.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/1629705880-27877-2-git-send-email-mkshah@codeaurora.org
2021-08-10KVM: PPC: Book3S HV: XIVE: Fix mapping of passthrough interruptsCédric Le Goater
PCI MSI interrupt numbers are now mapped in a PCI-MSI domain but the underlying calls handling the passthrough of the interrupt in the guest need a number in the XIVE IRQ domain. Use the IRQ data mapped in the XIVE IRQ domain and not the one in the PCI-MSI domain. Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210701132750.1475580-16-clg@kaod.org
2021-06-10irqdomain: Introduce irq_resolve_mapping()Marc Zyngier
Rework irq_find_mapping() to return an both an irq_desc pointer, optionally the virtual irq number, and rename the result to __irq_resolve_mapping(). a new helper called irq_resolve_mapping() is provided for code that doesn't need the virtual irq number. irq_find_mapping() is also rewritten in terms of __irq_resolve_mapping(). Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-06-10irqdomain: Protect the linear revmap with RCUMarc Zyngier
It is pretty odd that the radix tree uses RCU while the linear portion doesn't, leading to potential surprises for the users, depending on how the irqdomain has been created. Fix this by moving the update of the linear revmap under the mutex, and the lookup under the RCU read-side lock. The mutex name is updated to reflect that it doesn't only cover the radix-tree anymore. Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-06-10irqdomain: Cache irq_data instead of a virq number in the revmapMarc Zyngier
Caching a virq number in the revmap is pretty inefficient, as it means we will need to convert it back to either an irq_data or irq_desc to do anything with it. It is also a bit odd, as the radix tree does cache irq_data pointers. Change the revmap type to be an irq_data pointer instead of an unsigned int, and preserve the current API for now. Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-06-10irqdomain: Use struct_size() helper when allocating irqdomainMarc Zyngier
Instead of open-coding the size computation of struct irqdomain, use the struct_size() helper instead. This is going to be handy as we change the type of the revmap array. Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-06-10irqdomain: Make normal and nomap irqdomains exclusiveMarc Zyngier
Direct mappings are completely exclusive of normal mappings, meaning that we can refactor the code slightly so that we can get rid of the revmap_direct_max_irq field and use the revmap_size field instead, reducing the size of the irqdomain structure. Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-06-10powerpc: Move the use of irq_domain_add_nomap() behind a config optionMarc Zyngier
Only a handful of old PPC systems are still using the old 'nomap' variant of the irqdomain library. Move the associated definitions behind a configuration option, which will allow us to make some more radical changes. Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-06-10irqdomain: Reimplement irq_linear_revmap() with irq_find_mapping()Marc Zyngier
irq_linear_revmap() is supposed to be a fast path for domain lookups, but it only exposes low-level details of the irqdomain implementation, details which are better kept private. The *overhead* between the two is only a function call and a couple of tests, so it is likely that noone can show any meaningful difference compared to the cost of taking an interrupt. Reimplement irq_linear_revmap() with irq_find_mapping() in order to preserve source code compatibility, and rename the internal field for a measure. Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-05-05Merge tag 'gpio-updates-for-v5.13-v2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux Pull gpio updates from Bartosz Golaszewski: - new driver for the Realtek Otto GPIO controller - ACPI support for gpio-mpc8xxx - edge event support for gpio-sch (+ Kconfig fixes) - Kconfig improvements in gpio-ich - fixes to older issues in gpio-mockup - ACPI quirk for ignoring EC wakeups on Dell Venue 10 Pro 5055 - improve the GPIO aggregator code by using more generic interfaces instead of reimplementing them in the driver - convert the DT bindings for gpio-74x164 to yaml - documentation improvements - a slew of other minor fixes and improvements to GPIO drivers * tag 'gpio-updates-for-v5.13-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux: (34 commits) dt-bindings: gpio: add YAML description for rockchip,gpio-bank gpio: mxs: remove useless function dt-bindings: gpio: fairchild,74hc595: Convert to json-schema gpio: it87: remove unused code gpio: 104-dio-48e: Fix coding style issues gpio: mpc8xxx: Add ACPI support gpio: ich: Switch to be dependent on LPC_ICH gpio: sch: Drop MFD_CORE selection gpio: sch: depends on LPC_SCH gpiolib: acpi: Add quirk to ignore EC wakeups on Dell Venue 10 Pro 5055 gpio: sch: Hook into ACPI GPE handler to catch GPIO edge events gpio: sch: Add edge event support gpio: aggregator: Replace custom get_arg() with a generic next_arg() lib/cmdline: Export next_arg() for being used in modules gpio: omap: Use device_get_match_data() helper gpio: Add Realtek Otto GPIO support dt-bindings: gpio: Binding for Realtek Otto GPIO docs: kernel-parameters: Add gpio_mockup_named_lines docs: kernel-parameters: Move gpio-mockup for alphabetic order lib: bitmap: provide devm_bitmap_alloc() and devm_bitmap_zalloc() ...
2021-04-24Merge tag 'irqchip-5.13' of ↵Thomas Gleixner
git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core Pull irqchip and irqdomain updates from Marc Zyngier: New HW support: - New driver for the Nuvoton WPCM450 interrupt controller - New driver for the IDT 79rc3243x interrupt controller - Add support for interrupt trigger configuration to the MStar irqchip - Add more external interrupt support to the STM32 irqchip - Add new compatible strings for QCOM SC7280 to the qcom-pdc binding Fixes and cleanups: - Drop irq_create_strict_mappings() and irq_create_identity_mapping() from the irqdomain API, with cleanups in a couple of drivers - Fix nested NMI issue with spurious interrupts on GICv3 - Don't allow GICv4.1 vSGIs when the CPU doesn't support them - Various cleanups and minor fixes Link: https://lore.kernel.org/r/20210424094640.1731920-1-maz@kernel.org
2021-04-22irqdomain: Drop references to recusive irqdomain setupMarc Zyngier
It was never completely implemented, and was removed a long time ago. Adjust the documentation to reflect this. Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20210406093557.1073423-8-maz@kernel.org
2021-04-22irqdomain: Get rid of irq_create_strict_mappings()Marc Zyngier
No user of this helper is left, remove it. Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-04-07irqdomain: Get rid of irq_create_identity_mapping()Marc Zyngier
The sole user of irq_create_identity_mapping() having been converted, get rid of the unused helper. Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-03-26irqdomain: Introduce irq_domain_create_simple() APIAndy Shevchenko
Linus Walleij pointed out that ird_domain_add_simple() gained additional functionality and can't be anymore replaced with a simple conditional. In preparation to upgrade GPIO library to use fwnode, introduce irq_domain_create_simple() API which is functional equivalent to the existing irq_domain_add_simple(), but takes a pointer to the struct fwnode_handle as a parameter. While at it, amend documentation to mention irq_domain_create_*() functions where it makes sense. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2021-03-22irq: Fix typos in commentsIngo Molnar
Fix ~36 single-word typos in the IRQ, irqchip and irqdomain code comments. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Marc Zyngier <maz@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2021-03-08irqdomain: Remove debugfs_file from struct irq_domainGreg Kroah-Hartman
There's no need to keep around a dentry pointer to a simple file that debugfs itself can look up when we need to remove it from the system. So simplify the code by deleting the variable and cleaning up the logic around the debugfs file. Cc: Marc Zyngier <maz@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/YCvYV53ZdzQSWY6w@kroah.com
2021-02-09irqdomain: Mark fwnodes when their irqdomain is added/removedSaravana Kannan
This allows fw_devlink to recognize irqdomain drivers that don't use the device-driver model to initialize the device. fw_devlink will use this information to make sure consumers of such irqdomain aren't indefinitely blocked from probing, waiting for the irqdomain device to appear and bind to a driver. Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20210205222644.2357303-7-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-15Merge tag 'irq-core-2020-12-15' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq updates from Thomas Gleixner: "Generic interrupt and irqchips subsystem updates. Unusually, there is not a single completely new irq chip driver, just new DT bindings and extensions of existing drivers to accomodate new variants! Core: - Consolidation and robustness changes for irq time accounting - Cleanup and consolidation of irq stats - Remove the fasteoi IPI flow which has been proved useless - Provide an interface for converting legacy interrupt mechanism into irqdomains Drivers: - Preliminary support for managed interrupts on platform devices - Correctly identify allocation of MSIs proxyied by another device - Generalise the Ocelot support to new SoCs - Improve GICv4.1 vcpu entry, matching the corresponding KVM optimisation - Work around spurious interrupts on Qualcomm PDC - Random fixes and cleanups" * tag 'irq-core-2020-12-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits) irqchip/qcom-pdc: Fix phantom irq when changing between rising/falling driver core: platform: Add devm_platform_get_irqs_affinity() ACPI: Drop acpi_dev_irqresource_disabled() resource: Add irqresource_disabled() genirq/affinity: Add irq_update_affinity_desc() irqchip/gic-v3-its: Flag device allocation as proxied if behind a PCI bridge irqchip/gic-v3-its: Tag ITS device as shared if allocating for a proxy device platform-msi: Track shared domain allocation irqchip/ti-sci-intr: Fix freeing of irqs irqchip/ti-sci-inta: Fix printing of inta id on probe success drivers/irqchip: Remove EZChip NPS interrupt controller Revert "genirq: Add fasteoi IPI flow" irqchip/hip04: Make IPIs use handle_percpu_devid_irq() irqchip/bcm2836: Make IPIs use handle_percpu_devid_irq() irqchip/armada-370-xp: Make IPIs use handle_percpu_devid_irq() irqchip/gic, gic-v3: Make SGIs use handle_percpu_devid_irq() irqchip/ocelot: Add support for Jaguar2 platforms irqchip/ocelot: Add support for Serval platforms irqchip/ocelot: Add support for Luton platforms irqchip/ocelot: prepare to support more SoC ...
2020-12-15Merge tag 'driver-core-5.11-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the big driver core updates for 5.11-rc1 This time there was a lot of different work happening here for some reason: - redo of the fwnode link logic, speeding it up greatly - auxiliary bus added (this was a tag that will be pulled in from other trees/maintainers this merge window as well, as driver subsystems started to rely on it) - platform driver core cleanups on the way to fixing some long-time api updates in future releases - minor fixes and tweaks. All have been in linux-next with no (finally) reported issues. Testing there did helped in shaking issues out a lot :)" * tag 'driver-core-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (39 commits) driver core: platform: don't oops in platform_shutdown() on unbound devices ACPI: Use fwnode_init() to set up fwnode misc: pvpanic: Replace OF headers by mod_devicetable.h misc: pvpanic: Combine ACPI and platform drivers usb: host: sl811: Switch to use platform_get_mem_or_io() vfio: platform: Switch to use platform_get_mem_or_io() driver core: platform: Introduce platform_get_mem_or_io() dyndbg: fix use before null check soc: fix comment for freeing soc_dev_attr driver core: platform: use bus_type functions driver core: platform: change logic implementing platform_driver_probe driver core: platform: reorder functions driver core: make driver_probe_device() static driver core: Fix a couple of typos driver core: Reorder devices on successful probe driver core: Delete pointless parameter in fwnode_operations.add_links driver core: Refactor fw_devlink feature efi: Update implementation of add_links() to create fwnode links of: property: Update implementation of add_links() to create fwnode links driver core: Use device's fwnode to check if it is waiting for suppliers ...
2020-12-14Merge tag 'x86-apic-2020-12-14' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 apic updates from Thomas Gleixner: "Yet another large set of x86 interrupt management updates: - Simplification and distangling of the MSI related functionality - Let IO/APIC construct the RTE entries from an MSI message instead of having IO/APIC specific code in the interrupt remapping drivers - Make the retrieval of the parent interrupt domain (vector or remap unit) less hardcoded and use the relevant irqdomain callbacks for selection. - Allow the handling of more than 255 CPUs without a virtualized IOMMU when the hypervisor supports it. This has made been possible by the above modifications and also simplifies the existing workaround in the HyperV specific virtual IOMMU. - Cleanup of the historical timer_works() irq flags related inconsistencies" * tag 'x86-apic-2020-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (42 commits) x86/ioapic: Cleanup the timer_works() irqflags mess iommu/hyper-v: Remove I/O-APIC ID check from hyperv_irq_remapping_select() iommu/amd: Fix IOMMU interrupt generation in X2APIC mode iommu/amd: Don't register interrupt remapping irqdomain when IR is disabled iommu/amd: Fix union of bitfields in intcapxt support x86/ioapic: Correct the PCI/ISA trigger type selection x86/ioapic: Use I/O-APIC ID for finding irqdomain, not index x86/hyperv: Enable 15-bit APIC ID if the hypervisor supports it x86/kvm: Enable 15-bit extension when KVM_FEATURE_MSI_EXT_DEST_ID detected iommu/hyper-v: Disable IRQ pseudo-remapping if 15 bit APIC IDs are available x86/apic: Support 15 bits of APIC ID in MSI where available x86/ioapic: Handle Extended Destination ID field in RTE iommu/vt-d: Simplify intel_irq_remapping_select() x86: Kill all traces of irq_remapping_get_irq_domain() x86/ioapic: Use irq_find_matching_fwspec() to find remapping irqdomain x86/hpet: Use irq_find_matching_fwspec() to find remapping irqdomain iommu/hyper-v: Implement select() method on remapping irqdomain iommu/vt-d: Implement select() method on remapping irqdomain iommu/amd: Implement select() method on remapping irqdomain x86/apic: Add select() method on vector irqdomain ...
2020-12-09driver core: Add fwnode_init()Saravana Kannan
There are multiple locations in the kernel where a struct fwnode_handle is initialized. Add fwnode_init() so that we have one way of initializing a fwnode_handle. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20201121020232.908850-8-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-30genirq/irqdomain: Don't try to free an interrupt that has no mappingMarc Zyngier
When an interrupt allocation fails for N interrupts, it is pretty common for the error handling code to free the same number of interrupts, no matter how many interrupts have actually been allocated. This may result in the domain freeing code to be unexpectedly called for interrupts that have no mapping in that domain. Things end pretty badly. Instead, add some checks to irq_domain_free_irqs_hierarchy() to make sure that thiss does not follow the hierarchy if no mapping exists for a given interrupt. Fixes: 6a6544e520abe ("genirq/irqdomain: Remove auto-recursive hierarchy support") Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201129135551.396777-1-maz@kernel.org
2020-11-30genirq/irqdomain: Add an irq_create_mapping_affinity() functionLaurent Vivier
There is currently no way to convey the affinity of an interrupt via irq_create_mapping(), which creates issues for devices that expect that affinity to be managed by the kernel. In order to sort this out, rename irq_create_mapping() to irq_create_mapping_affinity() with an additional affinity parameter that can be passed down to irq_domain_alloc_descs(). irq_create_mapping() is re-implemented as a wrapper around irq_create_mapping_affinity(). No functional change. Fixes: e75eafb9b039 ("genirq/msi: Switch to new irq spreading infrastructure") Signed-off-by: Laurent Vivier <lvivier@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Greg Kurz <groug@kaod.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20201126082852.1178497-2-lvivier@redhat.com
2020-11-15genirq/irqdomain: Make irq_domain_disassociate() staticThomas Gleixner
No users outside of the core code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/87a6vja7mb.fsf@nanos.tec.linutronix.de
2020-11-07irqdomain: Introduce irq_domain_create_legacy() APIAndy Shevchenko
Introduce irq_domain_create_legacy() API which is functional equivalent to the existing irq_domain_add_legacy(), but takes a pointer to the struct fwnode_handle as a parameter. This is useful for non OF systems. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: https://lore.kernel.org/r/20201030165919.86234-5-andriy.shevchenko@linux.intel.com
2020-11-07irqdomain: Replace open coded of_node_to_fwnode()Andy Shevchenko
of_node_to_fwnode() should be used for conversion. Replace the open coded variant of it in of_phandle_args_to_fwspec(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: https://lore.kernel.org/r/20201030165919.86234-4-andriy.shevchenko@linux.intel.com
2020-10-28genirq/irqdomain: Implement get_name() method on irqchip fwnodesDavid Woodhouse
Prerequisite to make x86 more irqdomain compliant. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20201024213535.443185-23-dwmw2@infradead.org
2020-10-10genirq/irqdomain: Allow partial trimming of irq_data hierarchyMarc Zyngier
It appears that some HW is ugly enough that not all the interrupts connected to a particular interrupt controller end up with the same hierarchy depth (some of them are terminated early). This leaves the irqchip hacker with only two choices, both equally bad: - create discrete domain chains, one for each "hierarchy depth", which is very hard to maintain - create fake hierarchy levels for the shallow paths, leading to all kind of problems (what are the safe hwirq values for these fake levels?) Implement the ability to cut short a single interrupt hierarchy from a level marked as being disconnected by using the new irq_domain_disconnect_hierarchy() helper. The irqdomain allocation code will then perform the trimming Signed-off-by: Marc Zyngier <maz@kernel.org>