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         u32 nr_intpol_bases;
  28         void __iomem **intpol_bases;
  29         u32 *intpol_words;
  30         u8 *intpol_idx;
  31         u16 *which_word;
  32 };
  33
  34 static int mtk_sysirq_set_type(struct irq_data *data, unsigned int type)
  35 {
  36         irq_hw_number_t hwirq = data->hwirq;
  37         struct mtk_sysirq_chip_data *chip_data = data->chip_data;
  38         u8 intpol_idx = chip_data->intpol_idx[hwirq];
  39         void __iomem *base;
  40         u32 offset, reg_index, value;
  41         unsigned long flags;
  42         int ret;
  43
  44         base = chip_data->intpol_bases[intpol_idx];
  45         reg_index = chip_data->which_word[hwirq];
  46         offset = hwirq & 0x1f;
  47
  48         spin_lock_irqsave(&chip_data->lock, flags);
  49         value = readl_relaxed(base + reg_index * 4);
  50         if (type == IRQ_TYPE_LEVEL_LOW || type == IRQ_TYPE_EDGE_FALLING) {
  51                 if (type == IRQ_TYPE_LEVEL_LOW)
  52                         type = IRQ_TYPE_LEVEL_HIGH;
  53                 else
  54                         type = IRQ_TYPE_EDGE_RISING;
  55                 value |= (1 << offset);
  56         } else {
  57                 value &= ~(1 << offset);
  58         }
  59
  60         writel_relaxed(value, base + reg_index * 4);
  61
  62         data = data->parent_data;
  63         ret = data->chip->irq_set_type(data, type);
  64         spin_unlock_irqrestore(&chip_data->lock, flags);
  65         return ret;
  66 }
  67
  68 static struct irq_chip mtk_sysirq_chip = {
  69         .name                   = "MT_SYSIRQ",
  70         .irq_mask               = irq_chip_mask_parent,
  71         .irq_unmask             = irq_chip_unmask_parent,
  72         .irq_eoi                = irq_chip_eoi_parent,
  73         .irq_set_type           = mtk_sysirq_set_type,
  74         .irq_retrigger          = irq_chip_retrigger_hierarchy,
  75         .irq_set_affinity       = irq_chip_set_affinity_parent,
  76 };
  77
  78 static int mtk_sysirq_domain_translate(struct irq_domain *d,
  79                                        struct irq_fwspec *fwspec,
  80                                        unsigned long *hwirq,
  81                                        unsigned int *type)
  82 {
  83         if (is_of_node(fwspec->fwnode)) {
  84                 if (fwspec->param_count != 3)
  85                         return -EINVAL;
  86
  87                 /* No PPI should point to this domain */
  88                 if (fwspec->param[0] != 0)
  89                         return -EINVAL;
  90
  91                 *hwirq = fwspec->param[1];
  92                 *type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK;
  93                 return 0;
  94         }
  95
  96         return -EINVAL;
  97 }
  98
  99 static int mtk_sysirq_domain_alloc(struct irq_domain *domain, unsigned int virq,
 100                                    unsigned int nr_irqs, void *arg)
 101 {
 102         int i;
 103         irq_hw_number_t hwirq;
 104         struct irq_fwspec *fwspec = arg;
 105         struct irq_fwspec gic_fwspec = *fwspec;
 106
 107         if (fwspec->param_count != 3)
 108                 return -EINVAL;
 109
 110         /* sysirq doesn't support PPI */
 111         if (fwspec->param[0])
 112                 return -EINVAL;
 113
 114         hwirq = fwspec->param[1];
 115         for (i = 0; i < nr_irqs; i++)
 116                 irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
 117                                               &mtk_sysirq_chip,
 118                                               domain->host_data);
 119
 120         gic_fwspec.fwnode = domain->parent->fwnode;
 121         return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &gic_fwspec);
 122 }
 123
 124 static const struct irq_domain_ops sysirq_domain_ops = {
 125         .translate      = mtk_sysirq_domain_translate,
 126         .alloc          = mtk_sysirq_domain_alloc,
 127         .free           = irq_domain_free_irqs_common,
 128 };
 129
 130 static int __init mtk_sysirq_of_init(struct device_node *node,
 131                                      struct device_node *parent)
 132 {
 133         struct irq_domain *domain, *domain_parent;
 134         struct mtk_sysirq_chip_data *chip_data;
 135         int ret, size, intpol_num = 0, nr_intpol_bases = 0, i = 0;
 136
 137         domain_parent = irq_find_host(parent);
 138         if (!domain_parent) {
 139                 pr_err("mtk_sysirq: interrupt-parent not found\n");
 140                 return -EINVAL;
 141         }
 142
 143         chip_data = kzalloc(sizeof(*chip_data), GFP_KERNEL);
 144         if (!chip_data)
 145                 return -ENOMEM;
 146
 147         while (of_get_address(node, i++, NULL, NULL))
 148                 nr_intpol_bases++;
 149
 150         if (nr_intpol_bases == 0) {
 151                 pr_err("mtk_sysirq: base address not specified\n");
 152                 ret = -EINVAL;
 153                 goto out_free_chip;
 154         }
 155
 156         chip_data->intpol_words = kcalloc(nr_intpol_bases,
 157                                           sizeof(*chip_data->intpol_words),
 158                                           GFP_KERNEL);
 159         if (!chip_data->intpol_words) {
 160                 ret = -ENOMEM;
 161                 goto out_free_chip;
 162         }
 163
 164         chip_data->intpol_bases = kcalloc(nr_intpol_bases,
 165                                           sizeof(*chip_data->intpol_bases),
 166                                           GFP_KERNEL);
 167         if (!chip_data->intpol_bases) {
 168                 ret = -ENOMEM;
 169                 goto out_free_intpol_words;
 170         }
 171
 172         for (i = 0; i < nr_intpol_bases; i++) {
 173                 struct resource res;
 174
 175                 ret = of_address_to_resource(node, i, &res);
 176                 size = resource_size(&res);
 177                 intpol_num += size * 8;
 178                 chip_data->intpol_words[i] = size / 4;
 179                 chip_data->intpol_bases[i] = of_iomap(node, i);
 180                 if (ret || !chip_data->intpol_bases[i]) {
 181                         pr_err("%s: couldn't map region %d\n",
 182                                node->full_name, i);
 183                         ret = -ENODEV;
 184                         goto out_free_intpol;
 185                 }
 186         }
 187
 188         chip_data->intpol_idx = kcalloc(intpol_num,
 189                                         sizeof(*chip_data->intpol_idx),
 190                                         GFP_KERNEL);
 191         if (!chip_data->intpol_idx) {
 192                 ret = -ENOMEM;
 193                 goto out_free_intpol;
 194         }
 195
 196         chip_data->which_word = kcalloc(intpol_num,
 197                                         sizeof(*chip_data->which_word),
 198                                         GFP_KERNEL);
 199         if (!chip_data->which_word) {
 200                 ret = -ENOMEM;
 201                 goto out_free_intpol_idx;
 202         }
 203
 204         /*
 205          * assign an index of the intpol_bases for each irq
 206          * to set it fast later
 207          */
 208         for (i = 0; i < intpol_num ; i++) {
 209                 u32 word = i / 32, j;
 210
 211                 for (j = 0; word >= chip_data->intpol_words[j] ; j++)
 212                         word -= chip_data->intpol_words[j];
 213
 214                 chip_data->intpol_idx[i] = j;
 215                 chip_data->which_word[i] = word;
 216         }
 217
 218         domain = irq_domain_add_hierarchy(domain_parent, 0, intpol_num, node,
 219                                           &sysirq_domain_ops, chip_data);
 220         if (!domain) {
 221                 ret = -ENOMEM;
 222                 goto out_free_which_word;
 223         }
 224         spin_lock_init(&chip_data->lock);
 225
 226         return 0;
 227
 228 out_free_which_word:
 229         kfree(chip_data->which_word);
 230 out_free_intpol_idx:
 231         kfree(chip_data->intpol_idx);
 232 out_free_intpol:
 233         for (i = 0; i < nr_intpol_bases; i++)
 234                 if (chip_data->intpol_bases[i])
 235                         iounmap(chip_data->intpol_bases[i]);
 236         kfree(chip_data->intpol_bases);
 237 out_free_intpol_words:
 238         kfree(chip_data->intpol_words);
 239 out_free_chip:
 240         kfree(chip_data);
 241         return ret;
 242 }
 243 IRQCHIP_DECLARE(mtk_sysirq, "mediatek,mt6577-sysirq", mtk_sysirq_of_init);