From 015ec0386ab69a5b6b21f6c1559b242f4540de9f Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 20 Dec 2016 09:54:57 +0000 Subject: [PATCH] irqchip/gic-v3-its: Add VLPI configuration handling When a VLPI is reconfigured (enabled, disabled, change in priority), the full configuration byte must be written, and the caches invalidated. Also, when using the irq_mask/irq_unmask methods, it is necessary to disable the doorbell for that particular interrupt (by mapping it to 1023) on top of clearing the Enable bit. Reviewed-by: Thomas Gleixner Reviewed-by: Eric Auger Signed-off-by: Marc Zyngier --- drivers/irqchip/irq-gic-v3-its.c | 75 +++++++++++++++++++++++++++++--- 1 file changed, 70 insertions(+), 5 deletions(-) diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c index 5187c4b116d4..0aa4d609a8e9 100644 --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -812,18 +812,26 @@ static inline u32 its_get_event_id(struct irq_data *d) return d->hwirq - its_dev->event_map.lpi_base; } -static void lpi_update_config(struct irq_data *d, u8 clr, u8 set) +static void lpi_write_config(struct irq_data *d, u8 clr, u8 set) { - struct its_device *its_dev = irq_data_get_irq_chip_data(d); - irq_hw_number_t hwirq = d->hwirq; + irq_hw_number_t hwirq; struct page *prop_page; u8 *cfg; - prop_page = gic_rdists->prop_page; + if (irqd_is_forwarded_to_vcpu(d)) { + struct its_device *its_dev = irq_data_get_irq_chip_data(d); + u32 event = its_get_event_id(d); + + prop_page = its_dev->event_map.vm->vprop_page; + hwirq = its_dev->event_map.vlpi_maps[event].vintid; + } else { + prop_page = gic_rdists->prop_page; + hwirq = d->hwirq; + } cfg = page_address(prop_page) + hwirq - 8192; *cfg &= ~clr; - *cfg |= set; + *cfg |= set | LPI_PROP_GROUP1; /* * Make the above write visible to the redistributors. @@ -834,16 +842,52 @@ static void lpi_update_config(struct irq_data *d, u8 clr, u8 set) gic_flush_dcache_to_poc(cfg, sizeof(*cfg)); else dsb(ishst); +} + +static void lpi_update_config(struct irq_data *d, u8 clr, u8 set) +{ + struct its_device *its_dev = irq_data_get_irq_chip_data(d); + + lpi_write_config(d, clr, set); its_send_inv(its_dev, its_get_event_id(d)); } +static void its_vlpi_set_doorbell(struct irq_data *d, bool enable) +{ + struct its_device *its_dev = irq_data_get_irq_chip_data(d); + u32 event = its_get_event_id(d); + + if (its_dev->event_map.vlpi_maps[event].db_enabled == enable) + return; + + its_dev->event_map.vlpi_maps[event].db_enabled = enable; + + /* + * More fun with the architecture: + * + * Ideally, we'd issue a VMAPTI to set the doorbell to its LPI + * value or to 1023, depending on the enable bit. But that + * would be issueing a mapping for an /existing/ DevID+EventID + * pair, which is UNPREDICTABLE. Instead, let's issue a VMOVI + * to the /same/ vPE, using this opportunity to adjust the + * doorbell. Mouahahahaha. We loves it, Precious. + */ + its_send_vmovi(its_dev, event); +} + static void its_mask_irq(struct irq_data *d) { + if (irqd_is_forwarded_to_vcpu(d)) + its_vlpi_set_doorbell(d, false); + lpi_update_config(d, LPI_PROP_ENABLED, 0); } static void its_unmask_irq(struct irq_data *d) { + if (irqd_is_forwarded_to_vcpu(d)) + its_vlpi_set_doorbell(d, true); + lpi_update_config(d, 0, LPI_PROP_ENABLED); } @@ -856,6 +900,10 @@ static int its_set_affinity(struct irq_data *d, const struct cpumask *mask_val, struct its_collection *target_col; u32 id = its_get_event_id(d); + /* A forwarded interrupt should use irq_set_vcpu_affinity */ + if (irqd_is_forwarded_to_vcpu(d)) + return -EINVAL; + /* lpi cannot be routed to a redistributor that is on a foreign node */ if (its_dev->its->flags & ITS_FLAGS_WORKAROUND_CAVIUM_23144) { if (its_dev->its->numa_node >= 0) { @@ -1024,6 +1072,22 @@ out: return ret; } +static int its_vlpi_prop_update(struct irq_data *d, struct its_cmd_info *info) +{ + struct its_device *its_dev = irq_data_get_irq_chip_data(d); + + if (!its_dev->event_map.vm || !irqd_is_forwarded_to_vcpu(d)) + return -EINVAL; + + if (info->cmd_type == PROP_UPDATE_AND_INV_VLPI) + lpi_update_config(d, 0xff, info->config); + else + lpi_write_config(d, 0xff, info->config); + its_vlpi_set_doorbell(d, !!(info->config & LPI_PROP_ENABLED)); + + return 0; +} + static int its_irq_set_vcpu_affinity(struct irq_data *d, void *vcpu_info) { struct its_device *its_dev = irq_data_get_irq_chip_data(d); @@ -1046,6 +1110,7 @@ static int its_irq_set_vcpu_affinity(struct irq_data *d, void *vcpu_info) case PROP_UPDATE_VLPI: case PROP_UPDATE_AND_INV_VLPI: + return its_vlpi_prop_update(d, info); default: return -EINVAL; -- 2.20.1