--- /dev/null
+/*
+ * 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);
projects / platform / kernel / linux-rpi.git / commitdiff