drivers/irqchip/spear-shirq.c

   1 /*
   2  * SPEAr platform shared irq layer source file
   3  *
   4  * Copyright (C) 2009-2012 ST Microelectronics
   5  * Viresh Kumar <viresh.linux@gmail.com>
   6  *
   7  * Copyright (C) 2012 ST Microelectronics
   8  * Shiraz Hashim <shiraz.linux.kernel@gmail.com>
   9  *
  10  * This file is licensed under the terms of the GNU General Public
  11  * License version 2. This program is licensed "as is" without any
  12  * warranty of any kind, whether express or implied.
  13  */
  14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  15
  16 #include <linux/err.h>
  17 #include <linux/export.h>
  18 #include <linux/interrupt.h>
  19 #include <linux/io.h>
  20 #include <linux/irq.h>
  21 #include <linux/irqdomain.h>
  22 #include <linux/irqchip/spear-shirq.h>
  23 #include <linux/of.h>
  24 #include <linux/of_address.h>
  25 #include <linux/of_irq.h>
  26 #include <linux/spinlock.h>
  27
  28 #include "irqchip.h"
  29
  30 static DEFINE_SPINLOCK(lock);
  31
  32 /* spear300 shared irq registers offsets and masks */
  33 #define SPEAR300_INT_ENB_MASK_REG       0x54
  34 #define SPEAR300_INT_STS_MASK_REG       0x58
  35
  36 static struct spear_shirq spear300_shirq_ras1 = {
  37         .irq_nr = 9,
  38         .irq_bit_off = 0,
  39         .regs = {
  40                 .enb_reg = SPEAR300_INT_ENB_MASK_REG,
  41                 .status_reg = SPEAR300_INT_STS_MASK_REG,
  42                 .clear_reg = -1,
  43         },
  44 };
  45
  46 static struct spear_shirq *spear300_shirq_blocks[] = {
  47         &spear300_shirq_ras1,
  48 };
  49
  50 /* spear310 shared irq registers offsets and masks */
  51 #define SPEAR310_INT_STS_MASK_REG       0x04
  52
  53 static struct spear_shirq spear310_shirq_ras1 = {
  54         .irq_nr = 8,
  55         .irq_bit_off = 0,
  56         .regs = {
  57                 .enb_reg = -1,
  58                 .status_reg = SPEAR310_INT_STS_MASK_REG,
  59                 .clear_reg = -1,
  60         },
  61 };
  62
  63 static struct spear_shirq spear310_shirq_ras2 = {
  64         .irq_nr = 5,
  65         .irq_bit_off = 8,
  66         .regs = {
  67                 .enb_reg = -1,
  68                 .status_reg = SPEAR310_INT_STS_MASK_REG,
  69                 .clear_reg = -1,
  70         },
  71 };
  72
  73 static struct spear_shirq spear310_shirq_ras3 = {
  74         .irq_nr = 1,
  75         .irq_bit_off = 13,
  76         .regs = {
  77                 .enb_reg = -1,
  78                 .status_reg = SPEAR310_INT_STS_MASK_REG,
  79                 .clear_reg = -1,
  80         },
  81 };
  82
  83 static struct spear_shirq spear310_shirq_intrcomm_ras = {
  84         .irq_nr = 3,
  85         .irq_bit_off = 14,
  86         .regs = {
  87                 .enb_reg = -1,
  88                 .status_reg = SPEAR310_INT_STS_MASK_REG,
  89                 .clear_reg = -1,
  90         },
  91 };
  92
  93 static struct spear_shirq *spear310_shirq_blocks[] = {
  94         &spear310_shirq_ras1,
  95         &spear310_shirq_ras2,
  96         &spear310_shirq_ras3,
  97         &spear310_shirq_intrcomm_ras,
  98 };
  99
 100 /* spear320 shared irq registers offsets and masks */
 101 #define SPEAR320_INT_STS_MASK_REG               0x04
 102 #define SPEAR320_INT_CLR_MASK_REG               0x04
 103 #define SPEAR320_INT_ENB_MASK_REG               0x08
 104
 105 static struct spear_shirq spear320_shirq_ras1 = {
 106         .irq_nr = 3,
 107         .irq_bit_off = 7,
 108         .regs = {
 109                 .enb_reg = -1,
 110                 .status_reg = SPEAR320_INT_STS_MASK_REG,
 111                 .clear_reg = SPEAR320_INT_CLR_MASK_REG,
 112                 .reset_to_clear = 1,
 113         },
 114 };
 115
 116 static struct spear_shirq spear320_shirq_ras2 = {
 117         .irq_nr = 1,
 118         .irq_bit_off = 10,
 119         .regs = {
 120                 .enb_reg = -1,
 121                 .status_reg = SPEAR320_INT_STS_MASK_REG,
 122                 .clear_reg = SPEAR320_INT_CLR_MASK_REG,
 123                 .reset_to_clear = 1,
 124         },
 125 };
 126
 127 static struct spear_shirq spear320_shirq_ras3 = {
 128         .irq_nr = 7,
 129         .irq_bit_off = 0,
 130         .invalid_irq = 1,
 131         .regs = {
 132                 .enb_reg = SPEAR320_INT_ENB_MASK_REG,
 133                 .reset_to_enb = 1,
 134                 .status_reg = SPEAR320_INT_STS_MASK_REG,
 135                 .clear_reg = SPEAR320_INT_CLR_MASK_REG,
 136                 .reset_to_clear = 1,
 137         },
 138 };
 139
 140 static struct spear_shirq spear320_shirq_intrcomm_ras = {
 141         .irq_nr = 11,
 142         .irq_bit_off = 11,
 143         .regs = {
 144                 .enb_reg = -1,
 145                 .status_reg = SPEAR320_INT_STS_MASK_REG,
 146                 .clear_reg = SPEAR320_INT_CLR_MASK_REG,
 147                 .reset_to_clear = 1,
 148         },
 149 };
 150
 151 static struct spear_shirq *spear320_shirq_blocks[] = {
 152         &spear320_shirq_ras3,
 153         &spear320_shirq_ras1,
 154         &spear320_shirq_ras2,
 155         &spear320_shirq_intrcomm_ras,
 156 };
 157
 158 static void shirq_irq_mask_unmask(struct irq_data *d, bool mask)
 159 {
 160         struct spear_shirq *shirq = irq_data_get_irq_chip_data(d);
 161         u32 val, offset = d->irq - shirq->irq_base;
 162         unsigned long flags;
 163
 164         if (shirq->regs.enb_reg == -1)
 165                 return;
 166
 167         spin_lock_irqsave(&lock, flags);
 168         val = readl(shirq->base + shirq->regs.enb_reg);
 169
 170         if (mask ^ shirq->regs.reset_to_enb)
 171                 val &= ~(0x1 << shirq->irq_bit_off << offset);
 172         else
 173                 val |= 0x1 << shirq->irq_bit_off << offset;
 174
 175         writel(val, shirq->base + shirq->regs.enb_reg);
 176         spin_unlock_irqrestore(&lock, flags);
 177
 178 }
 179
 180 static void shirq_irq_mask(struct irq_data *d)
 181 {
 182         shirq_irq_mask_unmask(d, 1);
 183 }
 184
 185 static void shirq_irq_unmask(struct irq_data *d)
 186 {
 187         shirq_irq_mask_unmask(d, 0);
 188 }
 189
 190 static struct irq_chip shirq_chip = {
 191         .name           = "spear-shirq",
 192         .irq_ack        = shirq_irq_mask,
 193         .irq_mask       = shirq_irq_mask,
 194         .irq_unmask     = shirq_irq_unmask,
 195 };
 196
 197 static void shirq_handler(unsigned irq, struct irq_desc *desc)
 198 {
 199         u32 i, j, val, mask, tmp;
 200         struct irq_chip *chip;
 201         struct spear_shirq *shirq = irq_get_handler_data(irq);
 202
 203         chip = irq_get_chip(irq);
 204         chip->irq_ack(&desc->irq_data);
 205
 206         mask = ((0x1 << shirq->irq_nr) - 1) << shirq->irq_bit_off;
 207         while ((val = readl(shirq->base + shirq->regs.status_reg) &
 208                                 mask)) {
 209
 210                 val >>= shirq->irq_bit_off;
 211                 for (i = 0, j = 1; i < shirq->irq_nr; i++, j <<= 1) {
 212
 213                         if (!(j & val))
 214                                 continue;
 215
 216                         generic_handle_irq(shirq->irq_base + i);
 217
 218                         /* clear interrupt */
 219                         if (shirq->regs.clear_reg == -1)
 220                                 continue;
 221
 222                         tmp = readl(shirq->base + shirq->regs.clear_reg);
 223                         if (shirq->regs.reset_to_clear)
 224                                 tmp &= ~(j << shirq->irq_bit_off);
 225                         else
 226                                 tmp |= (j << shirq->irq_bit_off);
 227                         writel(tmp, shirq->base + shirq->regs.clear_reg);
 228                 }
 229         }
 230         chip->irq_unmask(&desc->irq_data);
 231 }
 232
 233 static void __init spear_shirq_register(struct spear_shirq *shirq)
 234 {
 235         int i;
 236
 237         if (shirq->invalid_irq)
 238                 return;
 239
 240         irq_set_chained_handler(shirq->irq, shirq_handler);
 241         for (i = 0; i < shirq->irq_nr; i++) {
 242                 irq_set_chip_and_handler(shirq->irq_base + i,
 243                                          &shirq_chip, handle_simple_irq);
 244                 set_irq_flags(shirq->irq_base + i, IRQF_VALID);
 245                 irq_set_chip_data(shirq->irq_base + i, shirq);
 246         }
 247
 248         irq_set_handler_data(shirq->irq, shirq);
 249 }
 250
 251 static int __init shirq_init(struct spear_shirq **shirq_blocks, int block_nr,
 252                 struct device_node *np)
 253 {
 254         int i, irq_base, hwirq = 0, irq_nr = 0;
 255         static struct irq_domain *shirq_domain;
 256         void __iomem *base;
 257
 258         base = of_iomap(np, 0);
 259         if (!base) {
 260                 pr_err("%s: failed to map shirq registers\n", __func__);
 261                 return -ENXIO;
 262         }
 263
 264         for (i = 0; i < block_nr; i++)
 265                 irq_nr += shirq_blocks[i]->irq_nr;
 266
 267         irq_base = irq_alloc_descs(-1, 0, irq_nr, 0);
 268         if (IS_ERR_VALUE(irq_base)) {
 269                 pr_err("%s: irq desc alloc failed\n", __func__);
 270                 goto err_unmap;
 271         }
 272
 273         shirq_domain = irq_domain_add_legacy(np, irq_nr, irq_base, 0,
 274                         &irq_domain_simple_ops, NULL);
 275         if (WARN_ON(!shirq_domain)) {
 276                 pr_warn("%s: irq domain init failed\n", __func__);
 277                 goto err_free_desc;
 278         }
 279
 280         for (i = 0; i < block_nr; i++) {
 281                 shirq_blocks[i]->base = base;
 282                 shirq_blocks[i]->irq_base = irq_find_mapping(shirq_domain,
 283                                 hwirq);
 284                 shirq_blocks[i]->irq = irq_of_parse_and_map(np, i);
 285
 286                 spear_shirq_register(shirq_blocks[i]);
 287                 hwirq += shirq_blocks[i]->irq_nr;
 288         }
 289
 290         return 0;
 291
 292 err_free_desc:
 293         irq_free_descs(irq_base, irq_nr);
 294 err_unmap:
 295         iounmap(base);
 296         return -ENXIO;
 297 }
 298
 299 int __init spear300_shirq_of_init(struct device_node *np,
 300                 struct device_node *parent)
 301 {
 302         return shirq_init(spear300_shirq_blocks,
 303                         ARRAY_SIZE(spear300_shirq_blocks), np);
 304 }
 305 IRQCHIP_DECLARE(spear300_shirq, "st,spear300-shirq", spear300_shirq_of_init);
 306
 307 int __init spear310_shirq_of_init(struct device_node *np,
 308                 struct device_node *parent)
 309 {
 310         return shirq_init(spear310_shirq_blocks,
 311                         ARRAY_SIZE(spear310_shirq_blocks), np);
 312 }
 313 IRQCHIP_DECLARE(spear310_shirq, "st,spear310-shirq", spear310_shirq_of_init);
 314
 315 int __init spear320_shirq_of_init(struct device_node *np,
 316                 struct device_node *parent)
 317 {
 318         return shirq_init(spear320_shirq_blocks,
 319                         ARRAY_SIZE(spear320_shirq_blocks), np);
 320 }
 321 IRQCHIP_DECLARE(spear320_shirq, "st,spear320-shirq", spear320_shirq_of_init);