From d4d7b4ad2f05c03fb25252aea66f9f3cd7cfbe06 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Thu, 26 Oct 2017 10:44:07 +0100 Subject: [PATCH] irqchip/gic-v3-its: Setup VLPI properties at map time So far, we require the hypervisor to update the VLPI properties once the the VLPI mapping has been established. While this makes it easy for the ITS driver, it creates a window where an incoming interrupt can be delivered with an unknown set of properties. Not very nice. Instead, let's add a "properties" field to the mapping structure, and use that to configure the VLPI before it actually gets mapped. Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier --- drivers/irqchip/irq-gic-v3-its.c | 18 ++++++++++++++++-- include/linux/irqchip/arm-gic-v4.h | 2 ++ 2 files changed, 18 insertions(+), 2 deletions(-) diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c index 6a74f04..29b2ff5 100644 --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -1008,9 +1008,15 @@ static void lpi_write_config(struct irq_data *d, u8 clr, u8 set) 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); + struct its_vlpi_map *map; prop_page = its_dev->event_map.vm->vprop_page; - hwirq = its_dev->event_map.vlpi_maps[event].vintid; + map = &its_dev->event_map.vlpi_maps[event]; + hwirq = map->vintid; + + /* Remember the updated property */ + map->properties &= ~clr; + map->properties |= set | LPI_PROP_GROUP1; } else { prop_page = gic_rdists->prop_page; hwirq = d->hwirq; @@ -1249,12 +1255,20 @@ static int its_vlpi_map(struct irq_data *d, struct its_cmd_info *info) /* Ensure all the VPEs are mapped on this ITS */ its_map_vm(its_dev->its, info->map->vm); + /* + * Flag the interrupt as forwarded so that we can + * start poking the virtual property table. + */ + irqd_set_forwarded_to_vcpu(d); + + /* Write out the property to the prop table */ + lpi_write_config(d, 0xff, info->map->properties); + /* Drop the physical mapping */ its_send_discard(its_dev, event); /* and install the virtual one */ its_send_vmapti(its_dev, event); - irqd_set_forwarded_to_vcpu(d); /* Increment the number of VLPIs */ its_dev->event_map.nr_vlpis++; diff --git a/include/linux/irqchip/arm-gic-v4.h b/include/linux/irqchip/arm-gic-v4.h index 43cde15..447da8c 100644 --- a/include/linux/irqchip/arm-gic-v4.h +++ b/include/linux/irqchip/arm-gic-v4.h @@ -71,12 +71,14 @@ struct its_vpe { * @vm: Pointer to the GICv4 notion of a VM * @vpe: Pointer to the GICv4 notion of a virtual CPU (VPE) * @vintid: Virtual LPI number + * @properties: Priority and enable bits (as written in the prop table) * @db_enabled: Is the VPE doorbell to be generated? */ struct its_vlpi_map { struct its_vm *vm; struct its_vpe *vpe; u32 vintid; + u8 properties; bool db_enabled; }; -- 2.7.4