user/sven/linux.git/include/linux/msi.h, branch v5.4.146

PCI/MSI: Protect msi_desc::masked for multi-MSI

2021-08-18T06:57:03Z

commit 77e89afc25f30abd56e76a809ee2884d7c1b63ce upstream. Multi-MSI uses a single MSI descriptor and there is a single mask register when the device supports per vector masking. To avoid reading back the mask register the value is cached in the MSI descriptor and updates are done by clearing and setting bits in the cache and writing it to the device. But nothing protects msi_desc::masked and the mask register from being modified concurrently on two different CPUs for two different Linux interrupts which belong to the same multi-MSI descriptor. Add a lock to struct device and protect any operation on the mask and the mask register with it. This makes the update of msi_desc::masked unconditional, but there is no place which requires a modification of the hardware register without updating the masked cache. msi_mask_irq() is now an empty wrapper which will be cleaned up in follow up changes. The problem goes way back to the initial support of multi-MSI, but picking the commit which introduced the mask cache is a valid cut off point (2.6.30). Fixes: f2440d9acbe8 ("PCI MSI: Refactor interrupt masking code") Signed-off-by: Thomas Gleixner Tested-by: Marc Zyngier Reviewed-by: Marc Zyngier Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210729222542.726833414@linutronix.de Signed-off-by: Greg Kroah-Hartman

genirq/msi: Activate Multi-MSI early when MSI_FLAG_ACTIVATE_EARLY is set

2021-02-10T08:25:30Z

commit 4c457e8cb75eda91906a4f89fc39bde3f9a43922 upstream. When MSI_FLAG_ACTIVATE_EARLY is set (which is the case for PCI), __msi_domain_alloc_irqs() performs the activation of the interrupt (which in the case of PCI results in the endpoint being programmed) as soon as the interrupt is allocated. But it appears that this is only done for the first vector, introducing an inconsistent behaviour for PCI Multi-MSI. Fix it by iterating over the number of vectors allocated to each MSI descriptor. This is easily achieved by introducing a new "for_each_msi_vector" iterator, together with a tiny bit of refactoring. Fixes: f3b0946d629c ("genirq/msi: Make sure PCI MSIs are activated early") Reported-by: Shameer Kolothum Signed-off-by: Marc Zyngier Signed-off-by: Thomas Gleixner Tested-by: Shameer Kolothum Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210123122759.1781359-1-maz@kernel.org Signed-off-by: Greg Kroah-Hartman

PCI/MSI: Support allocating virtual MSI interrupts

2019-06-13T12:59:34Z

For NTB devices, we want to be able to trigger MSI interrupts through a memory window. In these cases we may want to use more interrupts than the NTB PCI device has available in its MSI-X table. We allow for this by creating a new 'virtual' interrupt. These interrupts are allocated as usual but are not programmed into the MSI-X table (as there may not be space for them). The MSI address and data will then handled through an NTB MSI library introduced later in this series. Signed-off-by: Logan Gunthorpe Acked-by: Bjorn Helgaas Signed-off-by: Jon Mason

Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2019-05-19T17:58:45Z

Pull IRQ chip updates from Ingo Molnar: "A late irqchips update: - New TI INTR/INTA set of drivers - Rewrite of the stm32mp1-exti driver as a platform driver - Update the IOMMU MSI mapping API to be RT friendly - A number of cleanups and other low impact fixes" * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits) iommu/dma-iommu: Remove iommu_dma_map_msi_msg() irqchip/gic-v3-mbi: Don't map the MSI page in mbi_compose_m{b, s}i_msg() irqchip/ls-scfg-msi: Don't map the MSI page in ls_scfg_msi_compose_msg() irqchip/gic-v3-its: Don't map the MSI page in its_irq_compose_msi_msg() irqchip/gicv2m: Don't map the MSI page in gicv2m_compose_msi_msg() iommu/dma-iommu: Split iommu_dma_map_msi_msg() in two parts genirq/msi: Add a new field in msi_desc to store an IOMMU cookie arm64: arch_k3: Enable interrupt controller drivers irqchip/ti-sci-inta: Add msi domain support soc: ti: Add MSI domain bus support for Interrupt Aggregator irqchip/ti-sci-inta: Add support for Interrupt Aggregator driver dt-bindings: irqchip: Introduce TISCI Interrupt Aggregator bindings irqchip/ti-sci-intr: Add support for Interrupt Router driver dt-bindings: irqchip: Introduce TISCI Interrupt router bindings gpio: thunderx: Use the default parent apis for {request,release}_resources genirq: Introduce irq_chip_{request,release}_resource_parent() apis firmware: ti_sci: Add helper apis to manage resources firmware: ti_sci: Add RM mapping table for am654 firmware: ti_sci: Add support for IRQ management firmware: ti_sci: Add support for RM core ops ...

genirq/msi: Add a new field in msi_desc to store an IOMMU cookie

2019-05-03T14:19:20Z

When an MSI doorbell is located downstream of an IOMMU, it is required to swizzle the physical address with an appropriately-mapped IOVA for any device attached to one of our DMA ops domain. At the moment, the allocation of the mapping may be done when composing the message. However, the composing may be done in non-preemtible context while the allocation requires to be called from preemptible context. A follow-up change will split the current logic in two functions requiring to keep an IOMMU cookie per MSI. A new field is introduced in msi_desc to store an IOMMU cookie. As the cookie may not be required in some configuration, the field is protected under a new config CONFIG_IRQ_MSI_IOMMU. A pair of helpers has also been introduced to access the field. Signed-off-by: Julien Grall Reviewed-by: Robin Murphy Reviewed-by: Eric Auger Signed-off-by: Marc Zyngier

soc: ti: Add MSI domain bus support for Interrupt Aggregator

2019-05-01T09:49:17Z

With the system coprocessor managing the range allocation of the inputs to Interrupt Aggregator, it is difficult to represent the device IRQs from DT. The suggestion is to use MSI in such cases where devices wants to allocate and group interrupts dynamically. Create a MSI domain bus layer that allocates and frees MSIs for a device. APIs that are implemented: - ti_sci_inta_msi_create_irq_domain() that creates a MSI domain - ti_sci_inta_msi_domain_alloc_irqs() that creates MSIs for the specified device and resource. - ti_sci_inta_msi_domain_free_irqs() frees the irqs attached to the device. - ti_sci_inta_msi_get_virq() for getting the virq attached to a specific event. Signed-off-by: Lokesh Vutla Signed-off-by: Marc Zyngier

PCI/MSI: Remove unused mask_msi_irq() and unmask_msi_irq()

2019-03-21T19:39:33Z

Change pcie-xilinx-nwl.c to use pci_msi_mask_irq() and pci_msi_unmask_irq() like all other PCI host controller drivers. Remove the now-unused mask_msi_irq() and unmask_msi_irq(). Signed-off-by: Bjorn Helgaas CC: Michal Simek CC: linux-arm-kernel@lists.infradead.org

PCI/MSI: Remove unused __write_msi_msg() and write_msi_msg()

2019-03-21T19:39:00Z

Remove unused __write_msi_msg() and write_msi_msg(). These were added by 83a18912b0e8 ("PCI/MSI: Rename write_msi_msg() to pci_write_msi_msg()"), they served their purpose, and they're no longer needed. Signed-off-by: Bjorn Helgaas CC: Jiang Liu # 83a18912b0e8 author

genirq/msi: Clean up usage of u8/u16 types

2019-02-08T19:30:10Z

The double underscore types are meant for compatibility in userspace headers which does not apply here. Therefore, change to use the standard no-underscore types. The origin of the double underscore types dates back to before the git era so I was not able to find a commit to see the original justification. Signed-off-by: Logan Gunthorpe Signed-off-by: Bjorn Helgaas

genirq/core: Introduce struct irq_affinity_desc

2018-12-19T10:32:08Z

The interrupt affinity management uses straight cpumask pointers to convey the automatically assigned affinity masks for managed interrupts. The core interrupt descriptor allocation also decides based on the pointer being non NULL whether an interrupt is managed or not. Devices which use managed interrupts usually have two classes of interrupts: - Interrupts for multiple device queues - Interrupts for general device management Currently both classes are treated the same way, i.e. as managed interrupts. The general interrupts get the default affinity mask assigned while the device queue interrupts are spread out over the possible CPUs. Treating the general interrupts as managed is both a limitation and under certain circumstances a bug. Assume the following situation: default_irq_affinity = 4..7 So if CPUs 4-7 are offlined, then the core code will shut down the device management interrupts because the last CPU in their affinity mask went offline. It's also a limitation because it's desired to allow manual placement of the general device interrupts for various reasons. If they are marked managed then the interrupt affinity setting from both user and kernel space is disabled. To remedy that situation it's required to convey more information than the cpumasks through various interfaces related to interrupt descriptor allocation. Instead of adding yet another argument, create a new data structure 'irq_affinity_desc' which for now just contains the cpumask. This struct can be expanded to convey auxilliary information in the next step. No functional change, just preparatory work. [ tglx: Simplified logic and clarified changelog ] Suggested-by: Thomas Gleixner Suggested-by: Bjorn Helgaas Signed-off-by: Dou Liyang Signed-off-by: Thomas Gleixner Cc: linux-pci@vger.kernel.org Cc: kashyap.desai@broadcom.com Cc: shivasharan.srikanteshwara@broadcom.com Cc: sumit.saxena@broadcom.com Cc: ming.lei@redhat.com Cc: hch@lst.de Cc: douliyang1@huawei.com Link: https://lkml.kernel.org/r/20181204155122.6327-2-douliyangs@gmail.com