Messages in this thread | | | From | Grant Likely <> | Subject | Re: [PATCH 6/8] irqdomain: Support identity mapped VIRQ allocation. | Date | Sat, 19 May 2012 14:21:40 -0600 |
| |
On Sat, 19 May 2012 15:11:46 +0900, Paul Mundt <lethal@linux-sh.org> wrote: > This adds a new irq_create_identity_mapping() routine to permit platforms > to utilize 1:1 identity mapping between hardware and linux IRQs for > domain population. The same semantics as irq_create_mapping() apply, > though in this case we only support irqdesc allocation at a static > location, rather than falling back on dynamic lookup. > > Signed-off-by: Paul Mundt <lethal@linux-sh.org> > --- > include/linux/irqdomain.h | 2 ++ > kernel/irq/irqdomain.c | 41 +++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 43 insertions(+), 0 deletions(-) > > diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h > index 5abb533..e32d2e7 100644 > --- a/include/linux/irqdomain.h > +++ b/include/linux/irqdomain.h > @@ -149,6 +149,8 @@ extern unsigned int irq_create_mapping(struct irq_domain *host, > extern void irq_dispose_mapping(unsigned int virq); > extern unsigned int irq_find_mapping(struct irq_domain *host, > irq_hw_number_t hwirq); > +extern unsigned int irq_create_identity_mapping(struct irq_domain *host, > + irq_hw_number_t hwirq); > extern unsigned int irq_create_direct_mapping(struct irq_domain *host); > extern void irq_radix_revmap_insert(struct irq_domain *host, unsigned int virq, > irq_hw_number_t hwirq); > diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c > index 5f0ca52..ac44781 100644 > --- a/kernel/irq/irqdomain.c > +++ b/kernel/irq/irqdomain.c > @@ -459,6 +459,47 @@ unsigned int irq_create_mapping(struct irq_domain *domain, > } > EXPORT_SYMBOL_GPL(irq_create_mapping); > > +/** > + * irq_create_identity_mapping() - Allocate an identity mapped irq > + * @domain: domain owning this hardware interrupt or NULL for default domain > + * @hwirq: hardware irq number in that domain space > + * > + * This routine is used to allocate IRQs with a 1:1 identity mapping > + * between the hardware and linux irq. > + */ > +unsigned int irq_create_identity_mapping(struct irq_domain *domain, > + irq_hw_number_t hwirq)
How about the following for an API (omitting error checking, and the actual names are up for debate):
int irq_domain_associate_many(struct irq_domain *domain, unsigned int irq_base, irq_hw_number_t hwirq_base, int count) { int i; for (i = 0; i < count; i++) irq_setup_virq(domain, irq_base + i, hwirq_base + i); } int irq_create_strict_mappings(struct irq_domain *domain, unsigned int irq_base, irq_hw_number_t hwirq_base, int count) { /* Allows for non-identity, but still static mappings of a * range of irq numbers */ irq_alloc_descs(irq_base, irq_base, irq_domain_nid(domain->of_node)); irq_domain_associate_many(domain, irq_base, hwirq, count); ... }
/* in header */ static int irq_create_identity_mapping(struct irq_domain *domain, irq_hw_number_t hwirq_base) { irq_create_strict_mappings(domain, hwirq_base, hwirq_base, 1); }
That would give the ability to either associated for pre-allocated irq_descs, or strict map for allocating a specific range of irqs.
> +{ > + int virq; > + > + pr_debug("irq: irq_create_identity_mapping(0x%p, 0x%lx)\n", > + domain, hwirq); > + > + if (domain == NULL) > + domain = irq_default_domain;
This is a new API, and I'm not a fan of the irq_default_domain usage so I'd like just drop the above too lines. My opinion is that if your calling into get a mapping, then the code really should know what domain it is requesting from. If a default domain really is needed, then there it should be explicit for the caller to find the default domain and then pass that in to this function.
> + if (domain == NULL) { > + WARN_ON(1); > + return 0; > + } > + > + virq = irq_alloc_desc_at(hwirq, irq_domain_nid(domain->of_node)); > + if (virq < 0) { > + pr_debug("irq: -> virq allocation failed\n"); > + return 0; > + } > + > + if (irq_setup_virq(domain, virq, hwirq)) { > + if (domain->revmap_type != IRQ_DOMAIN_MAP_LEGACY) > + irq_free_desc(virq); > + return 0; > + } > + > + pr_debug("irq: irq %lu identity mapped\n", hwirq); > + > + return virq; > +} > +EXPORT_SYMBOL_GPL(irq_create_identity_mapping); > + > unsigned int irq_create_of_mapping(struct device_node *controller, > const u32 *intspec, unsigned int intsize) > { > -- > 1.7.9.rc0.28.g0e1cf > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/
-- Grant Likely, B.Sc, P.Eng. Secret Lab Technologies, Ltd.
| |