From 1bc04f2cf8c2a1feadbd994f50c40bb145bf2989 Mon Sep 17 00:00:00 2001 From: Grant Likely Date: Tue, 14 Feb 2012 14:06:55 -0700 Subject: irq_domain: Add support for base irq and hwirq in legacy mappings Add support for a legacy mapping where irq = (hwirq - first_hwirq + first_irq) so that a controller driver can allocate a fixed range of irq_descs and use a simple calculation to translate back and forth between linux and hw irq numbers. This is needed to use an irq_domain with many of the ARM interrupt controller drivers that manage their own irq_desc allocations. Ultimately the goal is to migrate those drivers to use the linear revmap, but doing it this way allows each driver to be converted separately which makes the migration path easier. This patch generalizes the IRQ_DOMAIN_MAP_LEGACY method to use (first_irq-first_hwirq) as the offset between hwirq and linux irq number, and adds checks to make sure that the hwirq number does not exceed range assigned to the controller. Signed-off-by: Grant Likely Cc: Rob Herring Cc: Benjamin Herrenschmidt Cc: Thomas Gleixner Cc: Milton Miller Tested-by: Olof Johansson --- include/linux/irqdomain.h | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) (limited to 'include/linux/irqdomain.h') diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h index f95553fa6872..7fef39ed5523 100644 --- a/include/linux/irqdomain.h +++ b/include/linux/irqdomain.h @@ -39,6 +39,9 @@ struct device_node; struct irq_domain; struct of_device_id; +/* Number of irqs reserved for a legacy isa controller */ +#define NUM_ISA_INTERRUPTS 16 + /* This type is the placeholder for a hardware interrupt number. It has to * be big enough to enclose whatever representation is used by a given * platform. @@ -96,6 +99,11 @@ struct irq_domain { /* type of reverse mapping_technique */ unsigned int revmap_type; union { + struct { + unsigned int size; + unsigned int first_irq; + irq_hw_number_t first_hwirq; + } legacy; struct { unsigned int size; unsigned int *revmap; @@ -117,6 +125,9 @@ struct irq_domain { #ifdef CONFIG_IRQ_DOMAIN #ifdef CONFIG_PPC struct irq_domain *irq_domain_add_legacy(struct device_node *of_node, + unsigned int size, + unsigned int first_irq, + irq_hw_number_t first_hwirq, struct irq_domain_ops *ops, void *host_data); struct irq_domain *irq_domain_add_linear(struct device_node *of_node, @@ -130,11 +141,18 @@ struct irq_domain *irq_domain_add_tree(struct device_node *of_node, struct irq_domain_ops *ops, void *host_data); - extern struct irq_domain *irq_find_host(struct device_node *node); extern void irq_set_default_host(struct irq_domain *host); extern void irq_set_virq_count(unsigned int count); +static inline struct irq_domain *irq_domain_add_legacy_isa( + struct device_node *of_node, + struct irq_domain_ops *ops, + void *host_data) +{ + return irq_domain_add_legacy(of_node, NUM_ISA_INTERRUPTS, 0, 0, ops, + host_data); +} extern unsigned int irq_create_mapping(struct irq_domain *host, irq_hw_number_t hwirq); -- cgit v1.2.3