From b48ac83d6bbc20a973c3e8133fd1ebda873d026a Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Mon, 24 Nov 2014 14:35:16 +0000 Subject: [PATCH] irqchip: GICv3: ITS: MSI support Now, the bit of code that allow us to use the ITS as a MSI controller. Both MSI and MSI-X are supported. Signed-off-by: Marc Zyngier Link: https://lkml.kernel.org/r/1416839720-18400-10-git-send-email-marc.zyngier@arm.com Signed-off-by: Jason Cooper --- drivers/irqchip/irq-gic-v3-its.c | 176 +++++++++++++++++++++++++++++ include/linux/irqchip/arm-gic-v3.h | 6 + 2 files changed, 182 insertions(+) diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c index d687fd43fbbb..532c6df89992 100644 --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -587,12 +587,47 @@ static int its_set_affinity(struct irq_data *d, const struct cpumask *mask_val, return IRQ_SET_MASK_OK_DONE; } +static void its_irq_compose_msi_msg(struct irq_data *d, struct msi_msg *msg) +{ + struct its_device *its_dev = irq_data_get_irq_chip_data(d); + struct its_node *its; + u64 addr; + + its = its_dev->its; + addr = its->phys_base + GITS_TRANSLATER; + + msg->address_lo = addr & ((1UL << 32) - 1); + msg->address_hi = addr >> 32; + msg->data = its_get_event_id(d); +} + 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, + .irq_compose_msi_msg = its_irq_compose_msi_msg, +}; + +static void its_mask_msi_irq(struct irq_data *d) +{ + pci_msi_mask_irq(d); + irq_chip_mask_parent(d); +} + +static void its_unmask_msi_irq(struct irq_data *d) +{ + pci_msi_unmask_irq(d); + irq_chip_unmask_parent(d); +} + +static struct irq_chip its_msi_irq_chip = { + .name = "ITS-MSI", + .irq_unmask = its_unmask_msi_irq, + .irq_mask = its_mask_msi_irq, + .irq_eoi = irq_chip_eoi_parent, + .irq_write_msi_msg = pci_msi_domain_write_msg, }; /* @@ -1055,3 +1090,144 @@ static void its_free_device(struct its_device *its_dev) kfree(its_dev->itt); kfree(its_dev); } + +static int its_alloc_device_irq(struct its_device *dev, irq_hw_number_t *hwirq) +{ + int idx; + + idx = find_first_zero_bit(dev->lpi_map, dev->nr_lpis); + if (idx == dev->nr_lpis) + return -ENOSPC; + + *hwirq = dev->lpi_base + idx; + set_bit(idx, dev->lpi_map); + + /* Map the GIC irq ID to the device */ + its_send_mapvi(dev, *hwirq, idx); + + return 0; +} + +static int its_msi_prepare(struct irq_domain *domain, struct device *dev, + int nvec, msi_alloc_info_t *info) +{ + struct pci_dev *pdev; + struct its_node *its; + u32 dev_id; + struct its_device *its_dev; + + if (!dev_is_pci(dev)) + return -EINVAL; + + pdev = to_pci_dev(dev); + dev_id = PCI_DEVID(pdev->bus->number, pdev->devfn); + its = domain->parent->host_data; + + its_dev = its_find_device(its, dev_id); + if (WARN_ON(its_dev)) + return -EINVAL; + + its_dev = its_create_device(its, dev_id, nvec); + if (!its_dev) + return -ENOMEM; + + dev_dbg(&pdev->dev, "ITT %d entries, %d bits\n", nvec, ilog2(nvec)); + + info->scratchpad[0].ptr = its_dev; + info->scratchpad[1].ptr = dev; + return 0; +} + +static struct msi_domain_ops its_pci_msi_ops = { + .msi_prepare = its_msi_prepare, +}; + +static struct msi_domain_info its_pci_msi_domain_info = { + .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS | + MSI_FLAG_MULTI_PCI_MSI | MSI_FLAG_PCI_MSIX), + .ops = &its_pci_msi_ops, + .chip = &its_msi_irq_chip, +}; + +static int its_irq_gic_domain_alloc(struct irq_domain *domain, + unsigned int virq, + irq_hw_number_t hwirq) +{ + struct of_phandle_args args; + + args.np = domain->parent->of_node; + args.args_count = 3; + args.args[0] = GIC_IRQ_TYPE_LPI; + args.args[1] = hwirq; + args.args[2] = IRQ_TYPE_EDGE_RISING; + + return irq_domain_alloc_irqs_parent(domain, virq, 1, &args); +} + +static int its_irq_domain_alloc(struct irq_domain *domain, unsigned int virq, + unsigned int nr_irqs, void *args) +{ + msi_alloc_info_t *info = args; + struct its_device *its_dev = info->scratchpad[0].ptr; + irq_hw_number_t hwirq; + int err; + int i; + + for (i = 0; i < nr_irqs; i++) { + err = its_alloc_device_irq(its_dev, &hwirq); + if (err) + return err; + + err = its_irq_gic_domain_alloc(domain, virq + i, hwirq); + if (err) + return err; + + irq_domain_set_hwirq_and_chip(domain, virq + i, + hwirq, &its_irq_chip, its_dev); + dev_dbg(info->scratchpad[1].ptr, "ID:%d pID:%d vID:%d\n", + (int)(hwirq - its_dev->lpi_base), (int)hwirq, virq + i); + } + + return 0; +} + +static void its_irq_domain_free(struct irq_domain *domain, unsigned int virq, + unsigned int nr_irqs) +{ + struct irq_data *d = irq_domain_get_irq_data(domain, virq); + struct its_device *its_dev = irq_data_get_irq_chip_data(d); + int i; + + for (i = 0; i < nr_irqs; i++) { + struct irq_data *data = irq_domain_get_irq_data(domain, + virq + i); + int event = its_get_event_id(data); + + /* Stop the delivery of interrupts */ + its_send_discard(its_dev, event); + + /* Mark interrupt index as unused */ + clear_bit(event, its_dev->lpi_map); + + /* Nuke the entry in the domain */ + irq_domain_reset_irq_data(d); + } + + /* If all interrupts have been freed, start mopping the floor */ + if (bitmap_empty(its_dev->lpi_map, its_dev->nr_lpis)) { + its_lpi_free(its_dev->lpi_map, + its_dev->lpi_base, + its_dev->nr_lpis); + + /* Unmap device/itt */ + its_send_mapd(its_dev, 0); + its_free_device(its_dev); + } + + irq_domain_free_irqs_parent(domain, virq, nr_irqs); +} + +static const struct irq_domain_ops its_domain_ops = { + .alloc = its_irq_domain_alloc, + .free = its_irq_domain_free, +}; diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h index 21c9d70426d1..0ed30d7d9338 100644 --- a/include/linux/irqchip/arm-gic-v3.h +++ b/include/linux/irqchip/arm-gic-v3.h @@ -295,6 +295,12 @@ #include +/* + * We need a value to serve as a irq-type for LPIs. Choose one that will + * hopefully pique the interest of the reviewer. + */ +#define GIC_IRQ_TYPE_LPI 0xa110c8ed + struct rdists { struct { void __iomem *rd_base;