Thomas Bogendoerfer | 529ea36 | 2021-04-22 16:53:28 +0200 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | /* |
| 3 | * Driver for IDT/Renesas 79RC3243x Interrupt Controller. |
| 4 | */ |
| 5 | |
| 6 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| 7 | |
| 8 | #include <linux/interrupt.h> |
| 9 | #include <linux/irq.h> |
| 10 | #include <linux/irqchip.h> |
| 11 | #include <linux/irqchip/chained_irq.h> |
| 12 | #include <linux/irqdomain.h> |
| 13 | #include <linux/of_address.h> |
| 14 | #include <linux/of_irq.h> |
| 15 | |
| 16 | #define IDT_PIC_NR_IRQS 32 |
| 17 | |
| 18 | #define IDT_PIC_IRQ_PEND 0x00 |
| 19 | #define IDT_PIC_IRQ_MASK 0x08 |
| 20 | |
| 21 | struct idt_pic_data { |
| 22 | void __iomem *base; |
| 23 | struct irq_domain *irq_domain; |
| 24 | struct irq_chip_generic *gc; |
| 25 | }; |
| 26 | |
| 27 | static void idt_irq_dispatch(struct irq_desc *desc) |
| 28 | { |
| 29 | struct idt_pic_data *idtpic = irq_desc_get_handler_data(desc); |
| 30 | struct irq_chip *host_chip = irq_desc_get_chip(desc); |
Marc Zyngier | 046a6ee | 2021-05-04 17:42:18 +0100 | [diff] [blame] | 31 | u32 pending, hwirq; |
Thomas Bogendoerfer | 529ea36 | 2021-04-22 16:53:28 +0200 | [diff] [blame] | 32 | |
| 33 | chained_irq_enter(host_chip, desc); |
| 34 | |
| 35 | pending = irq_reg_readl(idtpic->gc, IDT_PIC_IRQ_PEND); |
| 36 | pending &= ~idtpic->gc->mask_cache; |
| 37 | while (pending) { |
| 38 | hwirq = __fls(pending); |
Marc Zyngier | 046a6ee | 2021-05-04 17:42:18 +0100 | [diff] [blame] | 39 | generic_handle_domain_irq(idtpic->irq_domain, hwirq); |
Thomas Bogendoerfer | 529ea36 | 2021-04-22 16:53:28 +0200 | [diff] [blame] | 40 | pending &= ~(1 << hwirq); |
| 41 | } |
| 42 | |
| 43 | chained_irq_exit(host_chip, desc); |
| 44 | } |
| 45 | |
| 46 | static int idt_pic_init(struct device_node *of_node, struct device_node *parent) |
| 47 | { |
| 48 | struct irq_domain *domain; |
| 49 | struct idt_pic_data *idtpic; |
| 50 | struct irq_chip_generic *gc; |
| 51 | struct irq_chip_type *ct; |
| 52 | unsigned int parent_irq; |
| 53 | int ret = 0; |
| 54 | |
| 55 | idtpic = kzalloc(sizeof(*idtpic), GFP_KERNEL); |
| 56 | if (!idtpic) { |
| 57 | ret = -ENOMEM; |
| 58 | goto out_err; |
| 59 | } |
| 60 | |
| 61 | parent_irq = irq_of_parse_and_map(of_node, 0); |
| 62 | if (!parent_irq) { |
| 63 | pr_err("Failed to map parent IRQ!\n"); |
| 64 | ret = -EINVAL; |
| 65 | goto out_free; |
| 66 | } |
| 67 | |
| 68 | idtpic->base = of_iomap(of_node, 0); |
| 69 | if (!idtpic->base) { |
| 70 | pr_err("Failed to map base address!\n"); |
| 71 | ret = -ENOMEM; |
| 72 | goto out_unmap_irq; |
| 73 | } |
| 74 | |
| 75 | domain = irq_domain_add_linear(of_node, IDT_PIC_NR_IRQS, |
| 76 | &irq_generic_chip_ops, NULL); |
| 77 | if (!domain) { |
| 78 | pr_err("Failed to add irqdomain!\n"); |
| 79 | ret = -ENOMEM; |
| 80 | goto out_iounmap; |
| 81 | } |
| 82 | idtpic->irq_domain = domain; |
| 83 | |
| 84 | ret = irq_alloc_domain_generic_chips(domain, 32, 1, "IDTPIC", |
| 85 | handle_level_irq, 0, |
| 86 | IRQ_NOPROBE | IRQ_LEVEL, 0); |
| 87 | if (ret) |
| 88 | goto out_domain_remove; |
| 89 | |
| 90 | gc = irq_get_domain_generic_chip(domain, 0); |
| 91 | gc->reg_base = idtpic->base; |
| 92 | gc->private = idtpic; |
| 93 | |
| 94 | ct = gc->chip_types; |
| 95 | ct->regs.mask = IDT_PIC_IRQ_MASK; |
| 96 | ct->chip.irq_mask = irq_gc_mask_set_bit; |
| 97 | ct->chip.irq_unmask = irq_gc_mask_clr_bit; |
| 98 | idtpic->gc = gc; |
| 99 | |
| 100 | /* Mask interrupts. */ |
| 101 | writel(0xffffffff, idtpic->base + IDT_PIC_IRQ_MASK); |
| 102 | gc->mask_cache = 0xffffffff; |
| 103 | |
| 104 | irq_set_chained_handler_and_data(parent_irq, |
| 105 | idt_irq_dispatch, idtpic); |
| 106 | |
| 107 | return 0; |
| 108 | |
| 109 | out_domain_remove: |
| 110 | irq_domain_remove(domain); |
| 111 | out_iounmap: |
| 112 | iounmap(idtpic->base); |
| 113 | out_unmap_irq: |
| 114 | irq_dispose_mapping(parent_irq); |
| 115 | out_free: |
| 116 | kfree(idtpic); |
| 117 | out_err: |
| 118 | pr_err("Failed to initialize! (errno = %d)\n", ret); |
| 119 | return ret; |
| 120 | } |
| 121 | |
| 122 | IRQCHIP_DECLARE(idt_pic, "idt,32434-pic", idt_pic_init); |