diff options
Diffstat (limited to 'drivers/irqchip/irq-sni-exiu.c')
| -rw-r--r-- | drivers/irqchip/irq-sni-exiu.c | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-sni-exiu.c b/drivers/irqchip/irq-sni-exiu.c new file mode 100644 index 000000000000..1b6e2f7c59af --- /dev/null +++ b/drivers/irqchip/irq-sni-exiu.c @@ -0,0 +1,227 @@ +/* + * Driver for Socionext External Interrupt Unit (EXIU) + * + * Copyright (c) 2017 Linaro, Ltd. <ard.biesheuvel@linaro.org> + * + * Based on irq-tegra.c: + * Copyright (C) 2011 Google, Inc. + * Copyright (C) 2010,2013, NVIDIA Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/irqchip.h> +#include <linux/irqdomain.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> + +#include <dt-bindings/interrupt-controller/arm-gic.h> + +#define NUM_IRQS 32 + +#define EIMASK 0x00 +#define EISRCSEL 0x04 +#define EIREQSTA 0x08 +#define EIRAWREQSTA 0x0C +#define EIREQCLR 0x10 +#define EILVL 0x14 +#define EIEDG 0x18 +#define EISIR 0x1C + +struct exiu_irq_data { + void __iomem *base; + u32 spi_base; +}; + +static void exiu_irq_eoi(struct irq_data *d) +{ + struct exiu_irq_data *data = irq_data_get_irq_chip_data(d); + + writel(BIT(d->hwirq), data->base + EIREQCLR); + irq_chip_eoi_parent(d); +} + +static void exiu_irq_mask(struct irq_data *d) +{ + struct exiu_irq_data *data = irq_data_get_irq_chip_data(d); + u32 val; + + val = readl_relaxed(data->base + EIMASK) | BIT(d->hwirq); + writel_relaxed(val, data->base + EIMASK); + irq_chip_mask_parent(d); +} + +static void exiu_irq_unmask(struct irq_data *d) +{ + struct exiu_irq_data *data = irq_data_get_irq_chip_data(d); + u32 val; + + val = readl_relaxed(data->base + EIMASK) & ~BIT(d->hwirq); + writel_relaxed(val, data->base + EIMASK); + irq_chip_unmask_parent(d); +} + +static void exiu_irq_enable(struct irq_data *d) +{ + struct exiu_irq_data *data = irq_data_get_irq_chip_data(d); + u32 val; + + /* clear interrupts that were latched while disabled */ + writel_relaxed(BIT(d->hwirq), data->base + EIREQCLR); + + val = readl_relaxed(data->base + EIMASK) & ~BIT(d->hwirq); + writel_relaxed(val, data->base + EIMASK); + irq_chip_enable_parent(d); +} + +static int exiu_irq_set_type(struct irq_data *d, unsigned int type) +{ + struct exiu_irq_data *data = irq_data_get_irq_chip_data(d); + u32 val; + + val = readl_relaxed(data->base + EILVL); + if (type == IRQ_TYPE_EDGE_RISING || type == IRQ_TYPE_LEVEL_HIGH) + val |= BIT(d->hwirq); + else + val &= ~BIT(d->hwirq); + writel_relaxed(val, data->base + EILVL); + + val = readl_relaxed(data->base + EIEDG); + if (type == IRQ_TYPE_LEVEL_LOW || type == IRQ_TYPE_LEVEL_HIGH) + val &= ~BIT(d->hwirq); + else + val |= BIT(d->hwirq); + writel_relaxed(val, data->base + EIEDG); + + writel_relaxed(BIT(d->hwirq), data->base + EIREQCLR); + + return irq_chip_set_type_parent(d, IRQ_TYPE_LEVEL_HIGH); +} + +static struct irq_chip exiu_irq_chip = { + .name = "EXIU", + .irq_eoi = exiu_irq_eoi, + .irq_enable = exiu_irq_enable, + .irq_mask = exiu_irq_mask, + .irq_unmask = exiu_irq_unmask, + .irq_set_type = exiu_irq_set_type, + .irq_set_affinity = irq_chip_set_affinity_parent, + .flags = IRQCHIP_SET_TYPE_MASKED | + IRQCHIP_SKIP_SET_WAKE | + IRQCHIP_EOI_THREADED | + IRQCHIP_MASK_ON_SUSPEND, +}; + +static int exiu_domain_translate(struct irq_domain *domain, + struct irq_fwspec *fwspec, + unsigned long *hwirq, + unsigned int *type) +{ + struct exiu_irq_data *info = domain->host_data; + + if (is_of_node(fwspec->fwnode)) { + if (fwspec->param_count != 3) + return -EINVAL; + + if (fwspec->param[0] != GIC_SPI) + return -EINVAL; /* No PPI should point to this domain */ + + *hwirq = fwspec->param[1] - info->spi_base; + *type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK; + return 0; + } + return -EINVAL; +} + +static int exiu_domain_alloc(struct irq_domain *dom, unsigned int virq, + unsigned int nr_irqs, void *data) +{ + struct irq_fwspec *fwspec = data; + struct irq_fwspec parent_fwspec; + struct exiu_irq_data *info = dom->host_data; + irq_hw_number_t hwirq; + + if (fwspec->param_count != 3) + return -EINVAL; /* Not GIC compliant */ + if (fwspec->param[0] != GIC_SPI) + return -EINVAL; /* No PPI should point to this domain */ + + WARN_ON(nr_irqs != 1); + hwirq = fwspec->param[1] - info->spi_base; + irq_domain_set_hwirq_and_chip(dom, virq, hwirq, &exiu_irq_chip, info); + + parent_fwspec = *fwspec; + parent_fwspec.fwnode = dom->parent->fwnode; + return irq_domain_alloc_irqs_parent(dom, virq, nr_irqs, &parent_fwspec); +} + +static const struct irq_domain_ops exiu_domain_ops = { + .translate = exiu_domain_translate, + .alloc = exiu_domain_alloc, + .free = irq_domain_free_irqs_common, +}; + +static int __init exiu_init(struct device_node *node, + struct device_node *parent) +{ + struct irq_domain *parent_domain, *domain; + struct exiu_irq_data *data; + int err; + + if (!parent) { + pr_err("%pOF: no parent, giving up\n", node); + return -ENODEV; + } + + parent_domain = irq_find_host(parent); + if (!parent_domain) { + pr_err("%pOF: unable to obtain parent domain\n", node); + return -ENXIO; + } + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + if (of_property_read_u32(node, "socionext,spi-base", &data->spi_base)) { + pr_err("%pOF: failed to parse 'spi-base' property\n", node); + err = -ENODEV; + goto out_free; + } + + data->base = of_iomap(node, 0); + if (IS_ERR(data->base)) { + err = PTR_ERR(data->base); + goto out_free; + } + + /* clear and mask all interrupts */ + writel_relaxed(0xFFFFFFFF, data->base + EIREQCLR); + writel_relaxed(0xFFFFFFFF, data->base + EIMASK); + + domain = irq_domain_add_hierarchy(parent_domain, 0, NUM_IRQS, node, + &exiu_domain_ops, data); + if (!domain) { + pr_err("%pOF: failed to allocate domain\n", node); + err = -ENOMEM; + goto out_unmap; + } + + pr_info("%pOF: %d interrupts forwarded to %pOF\n", node, NUM_IRQS, + parent); + + return 0; + +out_unmap: + iounmap(data->base); +out_free: + kfree(data); + return err; +} +IRQCHIP_DECLARE(exiu, "socionext,synquacer-exiu", exiu_init); |