From 0317e0aba5d41ae5e974026bf96899d9ae4bcbdb Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Sun, 14 Dec 2025 12:23:41 -0800 Subject: genirq/msi: Correct kernel-doc in Eliminate all kernel-doc warnings in : - add "struct" to struct kernel-doc headers - add missing struct member descriptions or correct typos in them Fixes these warnings: Warning: include/linux/msi.h:60 cannot understand function prototype: 'struct msi_msg' Warning: include/linux/msi.h:73 struct member 'arch_addr_lo' not described in 'msi_msg' Warning: include/linux/msi.h:73 struct member 'arch_addr_hi' not described in 'msi_msg' Warning: include/linux/msi.h:106 cannot understand function prototype: 'struct pci_msi_desc' Warning: include/linux/msi.h:124 struct member 'msi_attrib' not described in 'pci_msi_desc' Warning: include/linux/msi.h:204 struct member 'sysfs_attrs' not described in 'msi_desc' Warning: include/linux/msi.h:227 struct member 'domain' not described in 'msi_dev_domain' Signed-off-by: Randy Dunlap Signed-off-by: Thomas Gleixner Link: https://patch.msgid.link/20251214202341.2205675-1-rdunlap@infradead.org --- include/linux/msi.h | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) (limited to 'include') diff --git a/include/linux/msi.h b/include/linux/msi.h index 8003e3218c46..94cfc3719077 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -49,12 +49,12 @@ typedef struct arch_msi_msg_data { #endif /** - * msi_msg - Representation of a MSI message + * struct msi_msg - Representation of a MSI message * @address_lo: Low 32 bits of msi message address - * @arch_addrlo: Architecture specific shadow of @address_lo + * @arch_addr_lo: Architecture specific shadow of @address_lo * @address_hi: High 32 bits of msi message address * (only used when device supports it) - * @arch_addrhi: Architecture specific shadow of @address_hi + * @arch_addr_hi: Architecture specific shadow of @address_hi * @data: MSI message data (usually 16 bits) * @arch_data: Architecture specific shadow of @data */ @@ -91,7 +91,7 @@ typedef void (*irq_write_msi_msg_t)(struct msi_desc *desc, struct msi_msg *msg); /** - * pci_msi_desc - PCI/MSI specific MSI descriptor data + * struct pci_msi_desc - PCI/MSI specific MSI descriptor data * * @msi_mask: [PCI MSI] MSI cached mask bits * @msix_ctrl: [PCI MSI-X] MSI-X cached per vector control bits @@ -101,6 +101,7 @@ typedef void (*irq_write_msi_msg_t)(struct msi_desc *desc, * @can_mask: [PCI MSI/X] Masking supported? * @is_64: [PCI MSI/X] Address size: 0=32bit 1=64bit * @default_irq:[PCI MSI/X] The default pre-assigned non-MSI irq + * @msi_attrib: [PCI MSI/X] Compound struct of MSI/X attributes * @mask_pos: [PCI MSI] Mask register position * @mask_base: [PCI MSI-X] Mask register base address */ @@ -169,7 +170,7 @@ struct msi_desc_data { * Only used if iommu_msi_shift != 0 * @iommu_msi_shift: Indicates how many bits of the original address should be * preserved when using iommu_msi_iova. - * @sysfs_attr: Pointer to sysfs device attribute + * @sysfs_attrs: Pointer to sysfs device attribute * * @write_msi_msg: Callback that may be called when the MSI message * address or data changes @@ -220,7 +221,7 @@ enum msi_desc_filter { /** * struct msi_dev_domain - The internals of MSI domain info per device * @store: Xarray for storing MSI descriptor pointers - * @irqdomain: Pointer to a per device interrupt domain + * @domain: Pointer to a per device interrupt domain */ struct msi_dev_domain { struct xarray store; -- cgit v1.2.3 From fcc1d0dabdb65ca069f77e5b76d3b20277be4a15 Mon Sep 17 00:00:00 2001 From: Radu Rendec Date: Fri, 28 Nov 2025 16:20:53 -0500 Subject: genirq: Add interrupt redirection infrastructure Add infrastructure to redirect interrupt handler execution to a different CPU when the current CPU is not part of the interrupt's CPU affinity mask. This is primarily aimed at (de)multiplexed interrupts, where the child interrupt handler runs in the context of the parent interrupt handler, and therefore CPU affinity control for the child interrupt is typically not available. With the new infrastructure, the child interrupt is allowed to freely change its affinity setting, independently of the parent. If the interrupt handler happens to be triggered on an "incompatible" CPU (a CPU that's not part of the child interrupt's affinity mask), the handler is redirected and runs in IRQ work context on a "compatible" CPU. No functional change is being made to any existing irqchip driver, and irqchip drivers must be explicitly modified to use the newly added infrastructure to support interrupt redirection. Originally-by: Thomas Gleixner Signed-off-by: Radu Rendec Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/linux-pci/878qpg4o4t.ffs@tglx/ Link: https://patch.msgid.link/20251128212055.1409093-2-rrendec@redhat.com --- include/linux/irq.h | 10 ++++++++++ include/linux/irqdesc.h | 17 ++++++++++++++++- 2 files changed, 26 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/irq.h b/include/linux/irq.h index 4a9f1d7b08c3..41d5bc53eefc 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -459,6 +459,8 @@ static inline irq_hw_number_t irqd_to_hwirq(struct irq_data *d) * checks against the supplied affinity mask are not * required. This is used for CPU hotplug where the * target CPU is not yet set in the cpu_online_mask. + * @irq_pre_redirect: Optional function to be invoked before redirecting + * an interrupt via irq_work. Called only on CONFIG_SMP. * @irq_retrigger: resend an IRQ to the CPU * @irq_set_type: set the flow type (IRQ_TYPE_LEVEL/etc.) of an IRQ * @irq_set_wake: enable/disable power-management wake-on of an IRQ @@ -503,6 +505,7 @@ struct irq_chip { void (*irq_eoi)(struct irq_data *data); int (*irq_set_affinity)(struct irq_data *data, const struct cpumask *dest, bool force); + void (*irq_pre_redirect)(struct irq_data *data); int (*irq_retrigger)(struct irq_data *data); int (*irq_set_type)(struct irq_data *data, unsigned int flow_type); int (*irq_set_wake)(struct irq_data *data, unsigned int on); @@ -687,6 +690,13 @@ extern int irq_chip_set_vcpu_affinity_parent(struct irq_data *data, extern int irq_chip_set_type_parent(struct irq_data *data, unsigned int type); extern int irq_chip_request_resources_parent(struct irq_data *data); extern void irq_chip_release_resources_parent(struct irq_data *data); +#ifdef CONFIG_SMP +void irq_chip_pre_redirect_parent(struct irq_data *data); +#endif +#endif + +#ifdef CONFIG_SMP +int irq_chip_redirect_set_affinity(struct irq_data *data, const struct cpumask *dest, bool force); #endif /* Disable or mask interrupts during a kernel kexec */ diff --git a/include/linux/irqdesc.h b/include/linux/irqdesc.h index 17902861de76..dae9a9b93665 100644 --- a/include/linux/irqdesc.h +++ b/include/linux/irqdesc.h @@ -2,9 +2,10 @@ #ifndef _LINUX_IRQDESC_H #define _LINUX_IRQDESC_H -#include +#include #include #include +#include /* * Core internal functions to deal with irq descriptors @@ -29,6 +30,17 @@ struct irqstat { #endif }; +/** + * struct irq_redirect - interrupt redirection metadata + * @work: Harg irq_work item for handler execution on a different CPU + * @target_cpu: CPU to run irq handler on in case the current CPU is not part + * of the irq affinity mask + */ +struct irq_redirect { + struct irq_work work; + unsigned int target_cpu; +}; + /** * struct irq_desc - interrupt descriptor * @irq_common_data: per irq and chip data passed down to chip functions @@ -46,6 +58,7 @@ struct irqstat { * @threads_handled: stats field for deferred spurious detection of threaded handlers * @threads_handled_last: comparator field for deferred spurious detection of threaded handlers * @lock: locking for SMP + * @redirect: Facility for redirecting interrupts via irq_work * @affinity_hint: hint to user space for preferred irq affinity * @affinity_notify: context for notification of affinity changes * @pending_mask: pending rebalanced interrupts @@ -83,6 +96,7 @@ struct irq_desc { raw_spinlock_t lock; struct cpumask *percpu_enabled; #ifdef CONFIG_SMP + struct irq_redirect redirect; const struct cpumask *affinity_hint; struct irq_affinity_notify *affinity_notify; #ifdef CONFIG_GENERIC_PENDING_IRQ @@ -185,6 +199,7 @@ int generic_handle_irq_safe(unsigned int irq); int generic_handle_domain_irq(struct irq_domain *domain, irq_hw_number_t hwirq); int generic_handle_domain_irq_safe(struct irq_domain *domain, irq_hw_number_t hwirq); int generic_handle_domain_nmi(struct irq_domain *domain, irq_hw_number_t hwirq); +bool generic_handle_demux_domain_irq(struct irq_domain *domain, irq_hw_number_t hwirq); #endif /* Test to see if a driver has successfully requested an irq */ -- cgit v1.2.3 From 386ced19e9a348e8131d20f009e692fa8fcc4568 Mon Sep 17 00:00:00 2001 From: Vivian Wang Date: Thu, 29 Jan 2026 09:56:06 +0800 Subject: PCI/MSI: Convert the boolean no_64bit_msi flag to a DMA address mask Some PCI devices have PCI_MSI_FLAGS_64BIT in the MSI capability, but implement less than 64 address bits. This breaks on platforms where such a device is assigned an MSI address higher than what's supported. Currently, no_64bit_msi bit is set for these devices, meaning that only 32-bit MSI addresses are allowed for them. However, on some platforms the MSI doorbell address is above the 32-bit limit but within the addressable range of the device. As a first step to enable MSI on those combinations of devices and platforms, convert the boolean no_64bit_msi flag to a DMA mask and fixup the affected usage sites: - no_64bit_msi = 1 -> msi_addr_mask = DMA_BIT_MASK(32) - no_64bit_msi = 0 -> msi_addr_mask = DMA_BIT_MASK(64) - if (no_64bit_msi) -> if (msi_addr_mask < DMA_BIT_MASK(64)) Since no values other than DMA_BIT_MASK(32) and DMA_BIT_MASK(64) are used, this is functionally equivalent. This prepares for changing the binary decision between 32 and 64 bit to a DMA mask based decision which allows to support systems which have a DMA address space less than 64bit but a MSI doorbell address above the 32-bit limit. [ tglx: Massaged changelog ] Signed-off-by: Vivian Wang Signed-off-by: Thomas Gleixner Reviewed-by: Brett Creeley # ionic Reviewed-by: Thomas Gleixner Acked-by: Takashi Iwai # sound Link: https://patch.msgid.link/20260129-pci-msi-addr-mask-v4-1-70da998f2750@iscas.ac.cn --- include/linux/pci.h | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/pci.h b/include/linux/pci.h index 864775651c6f..0fe32fef0331 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -377,6 +377,13 @@ struct pci_dev { 0xffffffff. You only need to change this if your device has broken DMA or supports 64-bit transfers. */ + u64 msi_addr_mask; /* Mask of the bits of bus address for + MSI that this device implements. + Normally set based on device + capabilities. You only need to + change this if your device claims + to support 64-bit MSI but implements + fewer than 64 address bits. */ struct device_dma_parameters dma_parms; @@ -441,7 +448,6 @@ struct pci_dev { unsigned int is_busmaster:1; /* Is busmaster */ unsigned int no_msi:1; /* May not use MSI */ - unsigned int no_64bit_msi:1; /* May only use 32-bit MSIs */ unsigned int block_cfg_access:1; /* Config space access blocked */ unsigned int broken_parity_status:1; /* Generates false positive parity */ unsigned int irq_reroute_variant:2; /* Needs IRQ rerouting variant */ -- cgit v1.2.3