From c48ed51c0d101ec4351530bdd6e1a01808f0a441 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Mon, 24 Nov 2014 14:35:12 +0000 Subject: [PATCH] irqchip: GICv3: ITS: irqchip implementation The usual methods that are used to present an irqchip to the rest of the kernel Signed-off-by: Marc Zyngier Link: https://lkml.kernel.org/r/1416839720-18400-6-git-send-email-marc.zyngier@arm.com Signed-off-by: Jason Cooper --- drivers/irqchip/irq-gic-v3-its.c | 77 ++++++++++++++++++++++++++++++++ 1 file changed, 77 insertions(+) diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c index a5ab12c7d7fc..d24bebdfb064 100644 --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -40,6 +40,8 @@ #define ITS_FLAGS_CMDQ_NEEDS_FLUSHING (1 << 0) +#define RDIST_FLAGS_PROPBASE_NEEDS_FLUSHING (1 << 0) + /* * Collection structure - just an ID, and a redistributor address to * ping. We use one per CPU as a bag of interrupts assigned to this @@ -509,3 +511,78 @@ static void its_send_invall(struct its_node *its, struct its_collection *col) its_send_single_command(its, its_build_invall_cmd, &desc); } + +/* + * irqchip functions - assumes MSI, mostly. + */ + +static inline u32 its_get_event_id(struct irq_data *d) +{ + struct its_device *its_dev = irq_data_get_irq_chip_data(d); + return d->hwirq - its_dev->lpi_base; +} + +static void lpi_set_config(struct irq_data *d, bool enable) +{ + struct its_device *its_dev = irq_data_get_irq_chip_data(d); + irq_hw_number_t hwirq = d->hwirq; + u32 id = its_get_event_id(d); + u8 *cfg = page_address(gic_rdists->prop_page) + hwirq - 8192; + + if (enable) + *cfg |= LPI_PROP_ENABLED; + else + *cfg &= ~LPI_PROP_ENABLED; + + /* + * Make the above write visible to the redistributors. + * And yes, we're flushing exactly: One. Single. Byte. + * Humpf... + */ + if (gic_rdists->flags & RDIST_FLAGS_PROPBASE_NEEDS_FLUSHING) + __flush_dcache_area(cfg, sizeof(*cfg)); + else + dsb(ishst); + its_send_inv(its_dev, id); +} + +static void its_mask_irq(struct irq_data *d) +{ + lpi_set_config(d, false); +} + +static void its_unmask_irq(struct irq_data *d) +{ + lpi_set_config(d, true); +} + +static void its_eoi_irq(struct irq_data *d) +{ + gic_write_eoir(d->hwirq); +} + +static int its_set_affinity(struct irq_data *d, const struct cpumask *mask_val, + bool force) +{ + unsigned int cpu = cpumask_any_and(mask_val, cpu_online_mask); + struct its_device *its_dev = irq_data_get_irq_chip_data(d); + struct its_collection *target_col; + u32 id = its_get_event_id(d); + + if (cpu >= nr_cpu_ids) + return -EINVAL; + + target_col = &its_dev->its->collections[cpu]; + its_send_movi(its_dev, target_col, id); + its_dev->collection = target_col; + + return IRQ_SET_MASK_OK_DONE; +} + +static struct irq_chip its_irq_chip = { + .name = "ITS", + .irq_mask = its_mask_irq, + .irq_unmask = its_unmask_irq, + .irq_eoi = its_eoi_irq, + .irq_set_affinity = its_set_affinity, +};