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