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 <vireshk@kernel.org>
   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/of.h>
  23 #include <linux/of_address.h>
  24 #include <linux/of_irq.h>
  25 #include <linux/spinlock.h>
  26
  27 #include "irqchip.h"
  28
  29 /*
  30  * struct spear_shirq: shared irq structure
  31  *
  32  * base:        Base register address
  33  * status_reg:  Status register offset for chained interrupt handler
  34  * mask_reg:    Mask register offset for irq chip
  35  * mask:        Mask to apply to the status register
  36  * virq_base:   Base virtual interrupt number
  37  * nr_irqs:     Number of interrupts handled by this block
  38  * offset:      Bit offset of the first interrupt
  39  * irq_chip:    Interrupt controller chip used for this instance,
  40  *              if NULL group is disabled, but accounted
  41  */
  42 struct spear_shirq {
  43         void __iomem            *base;
  44         u32                     status_reg;
  45         u32                     mask_reg;
  46         u32                     mask;
  47         u32                     virq_base;
  48         u32                     nr_irqs;
  49         u32                     offset;
  50         struct irq_chip         *irq_chip;
  51 };
  52
  53 /* spear300 shared irq registers offsets and masks */
  54 #define SPEAR300_INT_ENB_MASK_REG       0x54
  55 #define SPEAR300_INT_STS_MASK_REG       0x58
  56
  57 static DEFINE_RAW_SPINLOCK(shirq_lock);
  58
  59 static void shirq_irq_mask(struct irq_data *d)
  60 {
  61         struct spear_shirq *shirq = irq_data_get_irq_chip_data(d);
  62         u32 val, shift = d->irq - shirq->virq_base + shirq->offset;
  63         u32 __iomem *reg = shirq->base + shirq->mask_reg;
  64
  65         raw_spin_lock(&shirq_lock);
  66         val = readl(reg) & ~(0x1 << shift);
  67         writel(val, reg);
  68         raw_spin_unlock(&shirq_lock);
  69 }
  70
  71 static void shirq_irq_unmask(struct irq_data *d)
  72 {
  73         struct spear_shirq *shirq = irq_data_get_irq_chip_data(d);
  74         u32 val, shift = d->irq - shirq->virq_base + shirq->offset;
  75         u32 __iomem *reg = shirq->base + shirq->mask_reg;
  76
  77         raw_spin_lock(&shirq_lock);
  78         val = readl(reg) | (0x1 << shift);
  79         writel(val, reg);
  80         raw_spin_unlock(&shirq_lock);
  81 }
  82
  83 static struct irq_chip shirq_chip = {
  84         .name           = "spear-shirq",
  85         .irq_mask       = shirq_irq_mask,
  86         .irq_unmask     = shirq_irq_unmask,
  87 };
  88
  89 static struct spear_shirq spear300_shirq_ras1 = {
  90         .offset         = 0,
  91         .nr_irqs        = 9,
  92         .mask           = ((0x1 << 9) - 1) << 0,
  93         .irq_chip       = &shirq_chip,
  94         .status_reg     = SPEAR300_INT_STS_MASK_REG,
  95         .mask_reg       = SPEAR300_INT_ENB_MASK_REG,
  96 };
  97
  98 static struct spear_shirq *spear300_shirq_blocks[] = {
  99         &spear300_shirq_ras1,
 100 };
 101
 102 /* spear310 shared irq registers offsets and masks */
 103 #define SPEAR310_INT_STS_MASK_REG       0x04
 104
 105 static struct spear_shirq spear310_shirq_ras1 = {
 106         .offset         = 0,
 107         .nr_irqs        = 8,
 108         .mask           = ((0x1 << 8) - 1) << 0,
 109         .irq_chip       = &dummy_irq_chip,
 110         .status_reg     = SPEAR310_INT_STS_MASK_REG,
 111 };
 112
 113 static struct spear_shirq spear310_shirq_ras2 = {
 114         .offset         = 8,
 115         .nr_irqs        = 5,
 116         .mask           = ((0x1 << 5) - 1) << 8,
 117         .irq_chip       = &dummy_irq_chip,
 118         .status_reg     = SPEAR310_INT_STS_MASK_REG,
 119 };
 120
 121 static struct spear_shirq spear310_shirq_ras3 = {
 122         .offset         = 13,
 123         .nr_irqs        = 1,
 124         .mask           = ((0x1 << 1) - 1) << 13,
 125         .irq_chip       = &dummy_irq_chip,
 126         .status_reg     = SPEAR310_INT_STS_MASK_REG,
 127 };
 128
 129 static struct spear_shirq spear310_shirq_intrcomm_ras = {
 130         .offset         = 14,
 131         .nr_irqs        = 3,
 132         .mask           = ((0x1 << 3) - 1) << 14,
 133         .irq_chip       = &dummy_irq_chip,
 134         .status_reg     = SPEAR310_INT_STS_MASK_REG,
 135 };
 136
 137 static struct spear_shirq *spear310_shirq_blocks[] = {
 138         &spear310_shirq_ras1,
 139         &spear310_shirq_ras2,
 140         &spear310_shirq_ras3,
 141         &spear310_shirq_intrcomm_ras,
 142 };
 143
 144 /* spear320 shared irq registers offsets and masks */
 145 #define SPEAR320_INT_STS_MASK_REG               0x04
 146 #define SPEAR320_INT_CLR_MASK_REG               0x04
 147 #define SPEAR320_INT_ENB_MASK_REG               0x08
 148
 149 static struct spear_shirq spear320_shirq_ras3 = {
 150         .offset         = 0,
 151         .nr_irqs        = 7,
 152         .mask           = ((0x1 << 7) - 1) << 0,
 153 };
 154
 155 static struct spear_shirq spear320_shirq_ras1 = {
 156         .offset         = 7,
 157         .nr_irqs        = 3,
 158         .mask           = ((0x1 << 3) - 1) << 7,
 159         .irq_chip       = &dummy_irq_chip,
 160         .status_reg     = SPEAR320_INT_STS_MASK_REG,
 161 };
 162
 163 static struct spear_shirq spear320_shirq_ras2 = {
 164         .offset         = 10,
 165         .nr_irqs        = 1,
 166         .mask           = ((0x1 << 1) - 1) << 10,
 167         .irq_chip       = &dummy_irq_chip,
 168         .status_reg     = SPEAR320_INT_STS_MASK_REG,
 169 };
 170
 171 static struct spear_shirq spear320_shirq_intrcomm_ras = {
 172         .offset         = 11,
 173         .nr_irqs        = 11,
 174         .mask           = ((0x1 << 11) - 1) << 11,
 175         .irq_chip       = &dummy_irq_chip,
 176         .status_reg     = SPEAR320_INT_STS_MASK_REG,
 177 };
 178
 179 static struct spear_shirq *spear320_shirq_blocks[] = {
 180         &spear320_shirq_ras3,
 181         &spear320_shirq_ras1,
 182         &spear320_shirq_ras2,
 183         &spear320_shirq_intrcomm_ras,
 184 };
 185
 186 static void shirq_handler(unsigned irq, struct irq_desc *desc)
 187 {
 188         struct spear_shirq *shirq = irq_get_handler_data(irq);
 189         u32 pend;
 190
 191         pend = readl(shirq->base + shirq->status_reg) & shirq->mask;
 192         pend >>= shirq->offset;
 193
 194         while (pend) {
 195                 int irq = __ffs(pend);
 196
 197                 pend &= ~(0x1 << irq);
 198                 generic_handle_irq(shirq->virq_base + irq);
 199         }
 200 }
 201
 202 static void __init spear_shirq_register(struct spear_shirq *shirq,
 203                                         int parent_irq)
 204 {
 205         int i;
 206
 207         if (!shirq->irq_chip)
 208                 return;
 209
 210         irq_set_chained_handler_and_data(parent_irq, shirq_handler, shirq);
 211
 212         for (i = 0; i < shirq->nr_irqs; i++) {
 213                 irq_set_chip_and_handler(shirq->virq_base + i,
 214                                          shirq->irq_chip, handle_simple_irq);
 215                 set_irq_flags(shirq->virq_base + i, IRQF_VALID);
 216                 irq_set_chip_data(shirq->virq_base + i, shirq);
 217         }
 218 }
 219
 220 static int __init shirq_init(struct spear_shirq **shirq_blocks, int block_nr,
 221                 struct device_node *np)
 222 {
 223         int i, parent_irq, virq_base, hwirq = 0, nr_irqs = 0;
 224         struct irq_domain *shirq_domain;
 225         void __iomem *base;
 226
 227         base = of_iomap(np, 0);
 228         if (!base) {
 229                 pr_err("%s: failed to map shirq registers\n", __func__);
 230                 return -ENXIO;
 231         }
 232
 233         for (i = 0; i < block_nr; i++)
 234                 nr_irqs += shirq_blocks[i]->nr_irqs;
 235
 236         virq_base = irq_alloc_descs(-1, 0, nr_irqs, 0);
 237         if (IS_ERR_VALUE(virq_base)) {
 238                 pr_err("%s: irq desc alloc failed\n", __func__);
 239                 goto err_unmap;
 240         }
 241
 242         shirq_domain = irq_domain_add_legacy(np, nr_irqs, virq_base, 0,
 243                         &irq_domain_simple_ops, NULL);
 244         if (WARN_ON(!shirq_domain)) {
 245                 pr_warn("%s: irq domain init failed\n", __func__);
 246                 goto err_free_desc;
 247         }
 248
 249         for (i = 0; i < block_nr; i++) {
 250                 shirq_blocks[i]->base = base;
 251                 shirq_blocks[i]->virq_base = irq_find_mapping(shirq_domain,
 252                                 hwirq);
 253
 254                 parent_irq = irq_of_parse_and_map(np, i);
 255                 spear_shirq_register(shirq_blocks[i], parent_irq);
 256                 hwirq += shirq_blocks[i]->nr_irqs;
 257         }
 258
 259         return 0;
 260
 261 err_free_desc:
 262         irq_free_descs(virq_base, nr_irqs);
 263 err_unmap:
 264         iounmap(base);
 265         return -ENXIO;
 266 }
 267
 268 static int __init spear300_shirq_of_init(struct device_node *np,
 269                                          struct device_node *parent)
 270 {
 271         return shirq_init(spear300_shirq_blocks,
 272                         ARRAY_SIZE(spear300_shirq_blocks), np);
 273 }
 274 IRQCHIP_DECLARE(spear300_shirq, "st,spear300-shirq", spear300_shirq_of_init);
 275
 276 static int __init spear310_shirq_of_init(struct device_node *np,
 277                                          struct device_node *parent)
 278 {
 279         return shirq_init(spear310_shirq_blocks,
 280                         ARRAY_SIZE(spear310_shirq_blocks), np);
 281 }
 282 IRQCHIP_DECLARE(spear310_shirq, "st,spear310-shirq", spear310_shirq_of_init);
 283
 284 static int __init spear320_shirq_of_init(struct device_node *np,
 285                                          struct device_node *parent)
 286 {
 287         return shirq_init(spear320_shirq_blocks,
 288                         ARRAY_SIZE(spear320_shirq_blocks), np);
 289 }
 290 IRQCHIP_DECLARE(spear320_shirq, "st,spear320-shirq", spear320_shirq_of_init);