A MSI device may have multiple interrupts. That means that the interrupts numbers should be continuos so that pdev->irq refers to the first interrupt, pdev->irq + 1 to the second and so on. This patch adds support for continuous allocation of virqs for a range of hwirqs. The function is based on irq_create_mapping() but due to the number argument there is very little in common now.
Cc: Thomas Gleixner <t...@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bige...@linutronix.de> --- include/linux/irqdomain.h | 2 ++ kernel/irq/irqdomain.c | 61 +++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 63 insertions(+) diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h index c983ed1..21d0635 100644 --- a/include/linux/irqdomain.h +++ b/include/linux/irqdomain.h @@ -175,6 +175,8 @@ extern void irq_domain_associate_many(struct irq_domain *domain, extern unsigned int irq_create_mapping(struct irq_domain *host, irq_hw_number_t hwirq); +extern unsigned int irq_create_mapping_block(struct irq_domain *host, + irq_hw_number_t hwirq, unsigned int num); extern void irq_dispose_mapping(unsigned int virq); /** diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c index cf68bb3..323d417 100644 --- a/kernel/irq/irqdomain.c +++ b/kernel/irq/irqdomain.c @@ -433,6 +433,67 @@ unsigned int irq_create_mapping(struct irq_domain *domain, EXPORT_SYMBOL_GPL(irq_create_mapping); /** + * irq_create_mapping_block() - Map multiple hardware interrupts + * @domain: domain owning this hardware interrupt or NULL for default domain + * @hwirq: hardware irq number in that domain space + * @num: number of interrupts + * + * Maps a hwirq to a newly allocated virq. Num should be greater than 1 so num + * hwirqs (hwirq … hwirq + num - 1) will be mapped which and virq will be + * continuous. Returns the first linux virq number. + * + * If the sense/trigger is to be specified, set_irq_type() should be called + * on the number returned from that call. + */ +unsigned int irq_create_mapping_block(struct irq_domain *domain, + irq_hw_number_t hwirq, unsigned int num) +{ + int virq; + int i; + + pr_debug("%s(0x%p, 0x%lx) %d\n", __func__, domain, hwirq, num); + + if (num < 2) + return 0; + + /* Look for default domain if nececssary */ + if (domain == NULL) { + WARN(1, "%s(, %lx) called with NULL domain\n", __func__, hwirq); + return 0; + } + for (i = 0; i < num; i++) { + /* Check if mapping already exists */ + virq = irq_find_mapping(domain, hwirq); + if (virq != NO_IRQ) { + if (i == 0) { + pr_debug("-> existing mapping on virq %d\n", + virq); + return virq; + } + pr_err("irq: hwirq %ld has no mapping but hwirq %ld " + "maps to virq %d. This can't be a block\n", + hwirq, hwirq + i, virq); + return -EINVAL; + } + } + + /* Allocate a virtual interrupt number */ + virq = irq_alloc_descs_from(1, num, of_node_to_nid(domain->of_node)); + if (virq <= 0) { + pr_debug("-> virq allocation failed\n"); + return 0; + } + + irq_domain_associate_many(domain, virq, hwirq, num); + + pr_debug("irqs %lu…%lu on domain %s mapped to virtual irqs %u…%u\n", + hwirq, hwirq + num - 1, of_node_full_name(domain->of_node), + virq, virq + num - 1); + + return virq; +} + +/** * irq_create_strict_mappings() - Map a range of hw irqs to fixed linux irqs * @domain: domain owning the interrupt range * @irq_base: beginning of linux IRQ range -- 1.9.0.rc3 _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev