drivers/irqchip/irq-mtk-sysirq.c

   1 /*
   2  * Copyright (c) 2014 MediaTek Inc.
   3  * Author: Joe.C <yingjoe.chen@mediatek.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #include <linux/irq.h>
  16 #include <linux/irqchip.h>
  17 #include <linux/irqdomain.h>
  18 #include <linux/of.h>
  19 #include <linux/of_irq.h>
  20 #include <linux/of_address.h>
  21 #include <linux/io.h>
  22 #include <linux/slab.h>
  23 #include <linux/spinlock.h>
  24
  25 struct mtk_sysirq_chip_data {
  26         spinlock_t lock;
  27         void __iomem *intpol_base;
  28 };
  29
  30 static int mtk_sysirq_set_type(struct irq_data *data, unsigned int type)
  31 {
  32         irq_hw_number_t hwirq = data->hwirq;
  33         struct mtk_sysirq_chip_data *chip_data = data->chip_data;
  34         u32 offset, reg_index, value;
  35         unsigned long flags;
  36         int ret;
  37
  38         offset = hwirq & 0x1f;
  39         reg_index = hwirq >> 5;
  40
  41         spin_lock_irqsave(&chip_data->lock, flags);
  42         value = readl_relaxed(chip_data->intpol_base + reg_index * 4);
  43         if (type == IRQ_TYPE_LEVEL_LOW || type == IRQ_TYPE_EDGE_FALLING) {
  44                 if (type == IRQ_TYPE_LEVEL_LOW)
  45                         type = IRQ_TYPE_LEVEL_HIGH;
  46                 else
  47                         type = IRQ_TYPE_EDGE_RISING;
  48                 value |= (1 << offset);
  49         } else {
  50                 value &= ~(1 << offset);
  51         }
  52         writel(value, chip_data->intpol_base + reg_index * 4);
  53
  54         data = data->parent_data;
  55         ret = data->chip->irq_set_type(data, type);
  56         spin_unlock_irqrestore(&chip_data->lock, flags);
  57         return ret;
  58 }
  59
  60 static struct irq_chip mtk_sysirq_chip = {
  61         .name                   = "MT_SYSIRQ",
  62         .irq_mask               = irq_chip_mask_parent,
  63         .irq_unmask             = irq_chip_unmask_parent,
  64         .irq_eoi                = irq_chip_eoi_parent,
  65         .irq_set_type           = mtk_sysirq_set_type,
  66         .irq_retrigger          = irq_chip_retrigger_hierarchy,
  67         .irq_set_affinity       = irq_chip_set_affinity_parent,
  68 };
  69
  70 static int mtk_sysirq_domain_translate(struct irq_domain *d,
  71                                        struct irq_fwspec *fwspec,
  72                                        unsigned long *hwirq,
  73                                        unsigned int *type)
  74 {
  75         if (is_of_node(fwspec->fwnode)) {
  76                 if (fwspec->param_count != 3)
  77                         return -EINVAL;
  78
  79                 /* No PPI should point to this domain */
  80                 if (fwspec->param[0] != 0)
  81                         return -EINVAL;
  82
  83                 *hwirq = fwspec->param[1];
  84                 *type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK;
  85                 return 0;
  86         }
  87
  88         return -EINVAL;
  89 }
  90
  91 static int mtk_sysirq_domain_alloc(struct irq_domain *domain, unsigned int virq,
  92                                    unsigned int nr_irqs, void *arg)
  93 {
  94         int i;
  95         irq_hw_number_t hwirq;
  96         struct irq_fwspec *fwspec = arg;
  97         struct irq_fwspec gic_fwspec = *fwspec;
  98
  99         if (fwspec->param_count != 3)
 100                 return -EINVAL;
 101
 102         /* sysirq doesn't support PPI */
 103         if (fwspec->param[0])
 104                 return -EINVAL;
 105
 106         hwirq = fwspec->param[1];
 107         for (i = 0; i < nr_irqs; i++)
 108                 irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
 109                                               &mtk_sysirq_chip,
 110                                               domain->host_data);
 111
 112         gic_fwspec.fwnode = domain->parent->fwnode;
 113         return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &gic_fwspec);
 114 }
 115
 116 static const struct irq_domain_ops sysirq_domain_ops = {
 117         .translate      = mtk_sysirq_domain_translate,
 118         .alloc          = mtk_sysirq_domain_alloc,
 119         .free           = irq_domain_free_irqs_common,
 120 };
 121
 122 static int __init mtk_sysirq_of_init(struct device_node *node,
 123                                      struct device_node *parent)
 124 {
 125         struct irq_domain *domain, *domain_parent;
 126         struct mtk_sysirq_chip_data *chip_data;
 127         int ret, size, intpol_num;
 128         struct resource res;
 129
 130         domain_parent = irq_find_host(parent);
 131         if (!domain_parent) {
 132                 pr_err("mtk_sysirq: interrupt-parent not found\n");
 133                 return -EINVAL;
 134         }
 135
 136         ret = of_address_to_resource(node, 0, &res);
 137         if (ret)
 138                 return ret;
 139
 140         chip_data = kzalloc(sizeof(*chip_data), GFP_KERNEL);
 141         if (!chip_data)
 142                 return -ENOMEM;
 143
 144         size = resource_size(&res);
 145         intpol_num = size * 8;
 146         chip_data->intpol_base = ioremap(res.start, size);
 147         if (!chip_data->intpol_base) {
 148                 pr_err("mtk_sysirq: unable to map sysirq register\n");
 149                 ret = -ENXIO;
 150                 goto out_free;
 151         }
 152
 153         domain = irq_domain_add_hierarchy(domain_parent, 0, intpol_num, node,
 154                                           &sysirq_domain_ops, chip_data);
 155         if (!domain) {
 156                 ret = -ENOMEM;
 157                 goto out_unmap;
 158         }
 159         spin_lock_init(&chip_data->lock);
 160
 161         return 0;
 162
 163 out_unmap:
 164         iounmap(chip_data->intpol_base);
 165 out_free:
 166         kfree(chip_data);
 167         return ret;
 168 }
 169 IRQCHIP_DECLARE(mtk_sysirq, "mediatek,mt6577-sysirq", mtk_sysirq_of_init);