linux/drivers/irqchip/irq-tb10x.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Abilis Systems interrupt controller driver
   4 *
   5 * Copyright (C) Abilis Systems 2012
   6 *
   7 * Author: Christian Ruppert <christian.ruppert@abilis.com>
   8 */
   9
  10#include <linux/interrupt.h>
  11#include <linux/irqdomain.h>
  12#include <linux/irq.h>
  13#include <linux/irqchip.h>
  14#include <linux/of_irq.h>
  15#include <linux/of_address.h>
  16#include <linux/of_platform.h>
  17#include <linux/io.h>
  18#include <linux/slab.h>
  19#include <linux/bitops.h>
  20
  21#define AB_IRQCTL_INT_ENABLE   0x00
  22#define AB_IRQCTL_INT_STATUS   0x04
  23#define AB_IRQCTL_SRC_MODE     0x08
  24#define AB_IRQCTL_SRC_POLARITY 0x0C
  25#define AB_IRQCTL_INT_MODE     0x10
  26#define AB_IRQCTL_INT_POLARITY 0x14
  27#define AB_IRQCTL_INT_FORCE    0x18
  28
  29#define AB_IRQCTL_MAXIRQ       32
  30
  31static inline void ab_irqctl_writereg(struct irq_chip_generic *gc, u32 reg,
  32        u32 val)
  33{
  34        irq_reg_writel(gc, val, reg);
  35}
  36
  37static inline u32 ab_irqctl_readreg(struct irq_chip_generic *gc, u32 reg)
  38{
  39        return irq_reg_readl(gc, reg);
  40}
  41
  42static int tb10x_irq_set_type(struct irq_data *data, unsigned int flow_type)
  43{
  44        struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data);
  45        uint32_t im, mod, pol;
  46
  47        im = data->mask;
  48
  49        irq_gc_lock(gc);
  50
  51        mod = ab_irqctl_readreg(gc, AB_IRQCTL_SRC_MODE) | im;
  52        pol = ab_irqctl_readreg(gc, AB_IRQCTL_SRC_POLARITY) | im;
  53
  54        switch (flow_type & IRQF_TRIGGER_MASK) {
  55        case IRQ_TYPE_EDGE_FALLING:
  56                pol ^= im;
  57                break;
  58        case IRQ_TYPE_LEVEL_HIGH:
  59                mod ^= im;
  60                break;
  61        case IRQ_TYPE_NONE:
  62                flow_type = IRQ_TYPE_LEVEL_LOW;
  63        case IRQ_TYPE_LEVEL_LOW:
  64                mod ^= im;
  65                pol ^= im;
  66                break;
  67        case IRQ_TYPE_EDGE_RISING:
  68                break;
  69        default:
  70                irq_gc_unlock(gc);
  71                pr_err("%s: Cannot assign multiple trigger modes to IRQ %d.\n",
  72                        __func__, data->irq);
  73                return -EBADR;
  74        }
  75
  76        irqd_set_trigger_type(data, flow_type);
  77        irq_setup_alt_chip(data, flow_type);
  78
  79        ab_irqctl_writereg(gc, AB_IRQCTL_SRC_MODE, mod);
  80        ab_irqctl_writereg(gc, AB_IRQCTL_SRC_POLARITY, pol);
  81        ab_irqctl_writereg(gc, AB_IRQCTL_INT_STATUS, im);
  82
  83        irq_gc_unlock(gc);
  84
  85        return IRQ_SET_MASK_OK;
  86}
  87
  88static void tb10x_irq_cascade(struct irq_desc *desc)
  89{
  90        struct irq_domain *domain = irq_desc_get_handler_data(desc);
  91        unsigned int irq = irq_desc_get_irq(desc);
  92
  93        generic_handle_irq(irq_find_mapping(domain, irq));
  94}
  95
  96static int __init of_tb10x_init_irq(struct device_node *ictl,
  97                                        struct device_node *parent)
  98{
  99        int i, ret, nrirqs = of_irq_count(ictl);
 100        struct resource mem;
 101        struct irq_chip_generic *gc;
 102        struct irq_domain *domain;
 103        void __iomem *reg_base;
 104
 105        if (of_address_to_resource(ictl, 0, &mem)) {
 106                pr_err("%pOFn: No registers declared in DeviceTree.\n",
 107                        ictl);
 108                return -EINVAL;
 109        }
 110
 111        if (!request_mem_region(mem.start, resource_size(&mem),
 112                ictl->full_name)) {
 113                pr_err("%pOFn: Request mem region failed.\n", ictl);
 114                return -EBUSY;
 115        }
 116
 117        reg_base = ioremap(mem.start, resource_size(&mem));
 118        if (!reg_base) {
 119                ret = -EBUSY;
 120                pr_err("%pOFn: ioremap failed.\n", ictl);
 121                goto ioremap_fail;
 122        }
 123
 124        domain = irq_domain_add_linear(ictl, AB_IRQCTL_MAXIRQ,
 125                                        &irq_generic_chip_ops, NULL);
 126        if (!domain) {
 127                ret = -ENOMEM;
 128                pr_err("%pOFn: Could not register interrupt domain.\n",
 129                        ictl);
 130                goto irq_domain_add_fail;
 131        }
 132
 133        ret = irq_alloc_domain_generic_chips(domain, AB_IRQCTL_MAXIRQ,
 134                                2, ictl->name, handle_level_irq,
 135                                IRQ_NOREQUEST, IRQ_NOPROBE,
 136                                IRQ_GC_INIT_MASK_CACHE);
 137        if (ret) {
 138                pr_err("%pOFn: Could not allocate generic interrupt chip.\n",
 139                        ictl);
 140                goto gc_alloc_fail;
 141        }
 142
 143        gc = domain->gc->gc[0];
 144        gc->reg_base                         = reg_base;
 145
 146        gc->chip_types[0].type               = IRQ_TYPE_LEVEL_MASK;
 147        gc->chip_types[0].chip.irq_mask      = irq_gc_mask_clr_bit;
 148        gc->chip_types[0].chip.irq_unmask    = irq_gc_mask_set_bit;
 149        gc->chip_types[0].chip.irq_set_type  = tb10x_irq_set_type;
 150        gc->chip_types[0].regs.mask          = AB_IRQCTL_INT_ENABLE;
 151
 152        gc->chip_types[1].type               = IRQ_TYPE_EDGE_BOTH;
 153        gc->chip_types[1].chip.name          = gc->chip_types[0].chip.name;
 154        gc->chip_types[1].chip.irq_ack       = irq_gc_ack_set_bit;
 155        gc->chip_types[1].chip.irq_mask      = irq_gc_mask_clr_bit;
 156        gc->chip_types[1].chip.irq_unmask    = irq_gc_mask_set_bit;
 157        gc->chip_types[1].chip.irq_set_type  = tb10x_irq_set_type;
 158        gc->chip_types[1].regs.ack           = AB_IRQCTL_INT_STATUS;
 159        gc->chip_types[1].regs.mask          = AB_IRQCTL_INT_ENABLE;
 160        gc->chip_types[1].handler            = handle_edge_irq;
 161
 162        for (i = 0; i < nrirqs; i++) {
 163                unsigned int irq = irq_of_parse_and_map(ictl, i);
 164
 165                irq_set_chained_handler_and_data(irq, tb10x_irq_cascade,
 166                                                 domain);
 167        }
 168
 169        ab_irqctl_writereg(gc, AB_IRQCTL_INT_ENABLE, 0);
 170        ab_irqctl_writereg(gc, AB_IRQCTL_INT_MODE, 0);
 171        ab_irqctl_writereg(gc, AB_IRQCTL_INT_POLARITY, 0);
 172        ab_irqctl_writereg(gc, AB_IRQCTL_INT_STATUS, ~0UL);
 173
 174        return 0;
 175
 176gc_alloc_fail:
 177        irq_domain_remove(domain);
 178irq_domain_add_fail:
 179        iounmap(reg_base);
 180ioremap_fail:
 181        release_mem_region(mem.start, resource_size(&mem));
 182        return ret;
 183}
 184IRQCHIP_DECLARE(tb10x_intc, "abilis,tb10x-ictl", of_tb10x_init_irq);
 185