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path: root/drivers/irqchip/irq-idt3243x.c
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Diffstat (limited to 'drivers/irqchip/irq-idt3243x.c')
-rw-r--r--drivers/irqchip/irq-idt3243x.c122
1 files changed, 122 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-idt3243x.c b/drivers/irqchip/irq-idt3243x.c
new file mode 100644
index 000000000..0732a0e9a
--- /dev/null
+++ b/drivers/irqchip/irq-idt3243x.c
@@ -0,0 +1,122 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for IDT/Renesas 79RC3243x Interrupt Controller.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqchip.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/irqdomain.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#define IDT_PIC_NR_IRQS 32
+
+#define IDT_PIC_IRQ_PEND 0x00
+#define IDT_PIC_IRQ_MASK 0x08
+
+struct idt_pic_data {
+ void __iomem *base;
+ struct irq_domain *irq_domain;
+ struct irq_chip_generic *gc;
+};
+
+static void idt_irq_dispatch(struct irq_desc *desc)
+{
+ struct idt_pic_data *idtpic = irq_desc_get_handler_data(desc);
+ struct irq_chip *host_chip = irq_desc_get_chip(desc);
+ u32 pending, hwirq;
+
+ chained_irq_enter(host_chip, desc);
+
+ pending = irq_reg_readl(idtpic->gc, IDT_PIC_IRQ_PEND);
+ pending &= ~idtpic->gc->mask_cache;
+ while (pending) {
+ hwirq = __fls(pending);
+ generic_handle_domain_irq(idtpic->irq_domain, hwirq);
+ pending &= ~(1 << hwirq);
+ }
+
+ chained_irq_exit(host_chip, desc);
+}
+
+static int idt_pic_init(struct device_node *of_node, struct device_node *parent)
+{
+ struct irq_domain *domain;
+ struct idt_pic_data *idtpic;
+ struct irq_chip_generic *gc;
+ struct irq_chip_type *ct;
+ unsigned int parent_irq;
+ int ret = 0;
+
+ idtpic = kzalloc(sizeof(*idtpic), GFP_KERNEL);
+ if (!idtpic) {
+ ret = -ENOMEM;
+ goto out_err;
+ }
+
+ parent_irq = irq_of_parse_and_map(of_node, 0);
+ if (!parent_irq) {
+ pr_err("Failed to map parent IRQ!\n");
+ ret = -EINVAL;
+ goto out_free;
+ }
+
+ idtpic->base = of_iomap(of_node, 0);
+ if (!idtpic->base) {
+ pr_err("Failed to map base address!\n");
+ ret = -ENOMEM;
+ goto out_unmap_irq;
+ }
+
+ domain = irq_domain_add_linear(of_node, IDT_PIC_NR_IRQS,
+ &irq_generic_chip_ops, NULL);
+ if (!domain) {
+ pr_err("Failed to add irqdomain!\n");
+ ret = -ENOMEM;
+ goto out_iounmap;
+ }
+ idtpic->irq_domain = domain;
+
+ ret = irq_alloc_domain_generic_chips(domain, 32, 1, "IDTPIC",
+ handle_level_irq, 0,
+ IRQ_NOPROBE | IRQ_LEVEL, 0);
+ if (ret)
+ goto out_domain_remove;
+
+ gc = irq_get_domain_generic_chip(domain, 0);
+ gc->reg_base = idtpic->base;
+ gc->private = idtpic;
+
+ ct = gc->chip_types;
+ ct->regs.mask = IDT_PIC_IRQ_MASK;
+ ct->chip.irq_mask = irq_gc_mask_set_bit;
+ ct->chip.irq_unmask = irq_gc_mask_clr_bit;
+ idtpic->gc = gc;
+
+ /* Mask interrupts. */
+ writel(0xffffffff, idtpic->base + IDT_PIC_IRQ_MASK);
+ gc->mask_cache = 0xffffffff;
+
+ irq_set_chained_handler_and_data(parent_irq,
+ idt_irq_dispatch, idtpic);
+
+ return 0;
+
+out_domain_remove:
+ irq_domain_remove(domain);
+out_iounmap:
+ iounmap(idtpic->base);
+out_unmap_irq:
+ irq_dispose_mapping(parent_irq);
+out_free:
+ kfree(idtpic);
+out_err:
+ pr_err("Failed to initialize! (errno = %d)\n", ret);
+ return ret;
+}
+
+IRQCHIP_DECLARE(idt_pic, "idt,32434-pic", idt_pic_init);