arch/arm/mach-omap2/irq.c

   1 /*
   2  * linux/arch/arm/mach-omap2/irq.c
   3  *
   4  * Interrupt handler for OMAP2 boards.
   5  *
   6  * Copyright (C) 2005 Nokia Corporation
   7  * Author: Paul Mundt <paul.mundt@nokia.com>
   8  *
   9  * This file is subject to the terms and conditions of the GNU General Public
  10  * License. See the file "COPYING" in the main directory of this archive
  11  * for more details.
  12  */
  13 #include <linux/kernel.h>
  14 #include <linux/module.h>
  15 #include <linux/init.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/io.h>
  18
  19 #include <asm/exception.h>
  20 #include <asm/mach/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
  26 #include "soc.h"
  27 #include "iomap.h"
  28 #include "common.h"
  29
  30 /* selected INTC register offsets */
  31
  32 #define INTC_REVISION           0x0000
  33 #define INTC_SYSCONFIG          0x0010
  34 #define INTC_SYSSTATUS          0x0014
  35 #define INTC_SIR                0x0040
  36 #define INTC_CONTROL            0x0048
  37 #define INTC_PROTECTION         0x004C
  38 #define INTC_IDLE               0x0050
  39 #define INTC_THRESHOLD          0x0068
  40 #define INTC_MIR0               0x0084
  41 #define INTC_MIR_CLEAR0         0x0088
  42 #define INTC_MIR_SET0           0x008c
  43 #define INTC_PENDING_IRQ0       0x0098
  44 #define INTC_ILR0               0x0100
  45 /* Number of IRQ state bits in each MIR register */
  46 #define IRQ_BITS_PER_REG        32
  47
  48 #define OMAP2_IRQ_BASE          OMAP2_L4_IO_ADDRESS(OMAP24XX_IC_BASE)
  49 #define OMAP3_IRQ_BASE          OMAP2_L4_IO_ADDRESS(OMAP34XX_IC_BASE)
  50 #define INTCPS_SIR_IRQ_OFFSET   0x0040  /* omap2/3 active interrupt offset */
  51 #define ACTIVEIRQ_MASK          0x7f    /* omap2/3 active interrupt bits */
  52 #define INTCPS_NR_MIR_REGS      3
  53 #define INTCPS_NR_IRQS          96
  54
  55 /*
  56  * OMAP2 has a number of different interrupt controllers, each interrupt
  57  * controller is identified as its own "bank". Register definitions are
  58  * fairly consistent for each bank, but not all registers are implemented
  59  * for each bank.. when in doubt, consult the TRM.
  60  */
  61 static struct omap_irq_bank {
  62         void __iomem *base_reg;
  63         unsigned int nr_irqs;
  64 } __attribute__ ((aligned(4))) irq_banks[] = {
  65         {
  66                 /* MPU INTC */
  67                 .nr_irqs        = 96,
  68         },
  69 };
  70
  71 static struct irq_domain *domain;
  72 static void __iomem *omap_irq_base;
  73
  74 /* Structure to save interrupt controller context */
  75 struct omap3_intc_regs {
  76         u32 sysconfig;
  77         u32 protection;
  78         u32 idle;
  79         u32 threshold;
  80         u32 ilr[INTCPS_NR_IRQS];
  81         u32 mir[INTCPS_NR_MIR_REGS];
  82 };
  83
  84 /* INTC bank register get/set */
  85 static void intc_writel(u32 reg, u32 val)
  86 {
  87         writel_relaxed(val, omap_irq_base + reg);
  88 }
  89
  90 static u32 intc_readl(u32 reg)
  91 {
  92         return readl_relaxed(omap_irq_base + reg);
  93 }
  94
  95 /* XXX: FIQ and additional INTC support (only MPU at the moment) */
  96 static void omap_ack_irq(struct irq_data *d)
  97 {
  98         intc_writel(INTC_CONTROL, 0x1);
  99 }
 100
 101 static void omap_mask_ack_irq(struct irq_data *d)
 102 {
 103         irq_gc_mask_disable_reg(d);
 104         omap_ack_irq(d);
 105 }
 106
 107 static void __init omap_irq_bank_init_one(struct omap_irq_bank *bank)
 108 {
 109         unsigned long tmp;
 110
 111         tmp = intc_readl(INTC_REVISION) & 0xff;
 112         pr_info("IRQ: Found an INTC at 0x%p (revision %ld.%ld) with %d interrupts\n",
 113                 bank->base_reg, tmp >> 4, tmp & 0xf, bank->nr_irqs);
 114
 115         tmp = intc_readl(INTC_SYSCONFIG);
 116         tmp |= 1 << 1;  /* soft reset */
 117         intc_writel(INTC_SYSCONFIG, tmp);
 118
 119         while (!(intc_readl(INTC_SYSSTATUS) & 0x1))
 120                 /* Wait for reset to complete */;
 121
 122         /* Enable autoidle */
 123         intc_writel(INTC_SYSCONFIG, 1 << 0);
 124 }
 125
 126 int omap_irq_pending(void)
 127 {
 128         int i;
 129
 130         for (i = 0; i < ARRAY_SIZE(irq_banks); i++) {
 131                 struct omap_irq_bank *bank = irq_banks + i;
 132                 int irq;
 133
 134                 for (irq = 0; irq < bank->nr_irqs; irq += 32)
 135                         if (intc_readl(INTC_PENDING_IRQ0 +
 136                                                ((irq >> 5) << 5)))
 137                                 return 1;
 138         }
 139         return 0;
 140 }
 141
 142 static __init void
 143 omap_alloc_gc(void __iomem *base, unsigned int irq_start, unsigned int num)
 144 {
 145         struct irq_chip_generic *gc;
 146         struct irq_chip_type *ct;
 147
 148         gc = irq_alloc_generic_chip("INTC", 1, irq_start, base,
 149                                         handle_level_irq);
 150         ct = gc->chip_types;
 151         ct->chip.irq_ack = omap_mask_ack_irq;
 152         ct->chip.irq_mask = irq_gc_mask_disable_reg;
 153         ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
 154         ct->chip.flags |= IRQCHIP_SKIP_SET_WAKE;
 155
 156         ct->regs.enable = INTC_MIR_CLEAR0;
 157         ct->regs.disable = INTC_MIR_SET0;
 158         irq_setup_generic_chip(gc, IRQ_MSK(num), IRQ_GC_INIT_MASK_CACHE,
 159                                 IRQ_NOREQUEST | IRQ_NOPROBE, 0);
 160 }
 161
 162 static void __init omap_init_irq(u32 base, int nr_irqs,
 163                                  struct device_node *node)
 164 {
 165         unsigned long nr_of_irqs = 0;
 166         unsigned int nr_banks = 0;
 167         int i, j, irq_base;
 168
 169         omap_irq_base = ioremap(base, SZ_4K);
 170         if (WARN_ON(!omap_irq_base))
 171                 return;
 172
 173         irq_base = irq_alloc_descs(-1, 0, nr_irqs, 0);
 174         if (irq_base < 0) {
 175                 pr_warn("Couldn't allocate IRQ numbers\n");
 176                 irq_base = 0;
 177         }
 178
 179         domain = irq_domain_add_legacy(node, nr_irqs, irq_base, 0,
 180                                        &irq_domain_simple_ops, NULL);
 181
 182         for (i = 0; i < ARRAY_SIZE(irq_banks); i++) {
 183                 struct omap_irq_bank *bank = irq_banks + i;
 184
 185                 bank->nr_irqs = nr_irqs;
 186
 187                 /* Static mapping, never released */
 188                 bank->base_reg = ioremap(base, SZ_4K);
 189                 if (!bank->base_reg) {
 190                         pr_err("Could not ioremap irq bank%i\n", i);
 191                         continue;
 192                 }
 193
 194                 omap_irq_bank_init_one(bank);
 195
 196                 for (j = 0; j < bank->nr_irqs; j += 32)
 197                         omap_alloc_gc(bank->base_reg + j, j + irq_base, 32);
 198
 199                 nr_of_irqs += bank->nr_irqs;
 200                 nr_banks++;
 201         }
 202
 203         pr_info("Total of %ld interrupts on %d active controller%s\n",
 204                 nr_of_irqs, nr_banks, nr_banks > 1 ? "s" : "");
 205 }
 206
 207 void __init omap2_init_irq(void)
 208 {
 209         omap_init_irq(OMAP24XX_IC_BASE, 96, NULL);
 210 }
 211
 212 void __init omap3_init_irq(void)
 213 {
 214         omap_init_irq(OMAP34XX_IC_BASE, 96, NULL);
 215 }
 216
 217 void __init ti81xx_init_irq(void)
 218 {
 219         omap_init_irq(OMAP34XX_IC_BASE, 128, NULL);
 220 }
 221
 222 static inline void omap_intc_handle_irq(void __iomem *base_addr, struct pt_regs *regs)
 223 {
 224         u32 irqnr;
 225         int handled_irq = 0;
 226
 227         do {
 228                 irqnr = readl_relaxed(base_addr + 0x98);
 229                 if (irqnr)
 230                         goto out;
 231
 232                 irqnr = readl_relaxed(base_addr + 0xb8);
 233                 if (irqnr)
 234                         goto out;
 235
 236                 irqnr = readl_relaxed(base_addr + 0xd8);
 237 #if IS_ENABLED(CONFIG_SOC_TI81XX) || IS_ENABLED(CONFIG_SOC_AM33XX)
 238                 if (irqnr)
 239                         goto out;
 240                 irqnr = readl_relaxed(base_addr + 0xf8);
 241 #endif
 242
 243 out:
 244                 if (!irqnr)
 245                         break;
 246
 247                 irqnr = readl_relaxed(base_addr + INTCPS_SIR_IRQ_OFFSET);
 248                 irqnr &= ACTIVEIRQ_MASK;
 249
 250                 if (irqnr) {
 251                         irqnr = irq_find_mapping(domain, irqnr);
 252                         handle_IRQ(irqnr, regs);
 253                         handled_irq = 1;
 254                 }
 255         } while (irqnr);
 256
 257         /* If an irq is masked or deasserted while active, we will
 258          * keep ending up here with no irq handled. So remove it from
 259          * the INTC with an ack.*/
 260         if (!handled_irq)
 261                 omap_ack_irq(NULL);
 262 }
 263
 264 asmlinkage void __exception_irq_entry omap2_intc_handle_irq(struct pt_regs *regs)
 265 {
 266         void __iomem *base_addr = OMAP2_IRQ_BASE;
 267         omap_intc_handle_irq(base_addr, regs);
 268 }
 269
 270 int __init intc_of_init(struct device_node *node,
 271                              struct device_node *parent)
 272 {
 273         struct resource res;
 274         u32 nr_irq = 96;
 275
 276         if (WARN_ON(!node))
 277                 return -ENODEV;
 278
 279         if (of_address_to_resource(node, 0, &res)) {
 280                 WARN(1, "unable to get intc registers\n");
 281                 return -EINVAL;
 282         }
 283
 284         if (of_property_read_u32(node, "ti,intc-size", &nr_irq))
 285                 pr_warn("unable to get intc-size, default to %d\n", nr_irq);
 286
 287         omap_init_irq(res.start, nr_irq, of_node_get(node));
 288
 289         return 0;
 290 }
 291
 292 static const struct of_device_id irq_match[] __initconst = {
 293         { .compatible = "ti,omap2-intc", .data = intc_of_init, },
 294         { }
 295 };
 296
 297 void __init omap_intc_of_init(void)
 298 {
 299         of_irq_init(irq_match);
 300 }
 301
 302 #if defined(CONFIG_ARCH_OMAP3) || defined(CONFIG_SOC_AM33XX)
 303 static struct omap3_intc_regs intc_context[ARRAY_SIZE(irq_banks)];
 304
 305 void omap_intc_save_context(void)
 306 {
 307         int ind = 0, i = 0;
 308         for (ind = 0; ind < ARRAY_SIZE(irq_banks); ind++) {
 309                 intc_context[ind].sysconfig =
 310                         intc_readl(INTC_SYSCONFIG);
 311                 intc_context[ind].protection =
 312                         intc_readl(INTC_PROTECTION);
 313                 intc_context[ind].idle =
 314                         intc_readl(INTC_IDLE);
 315                 intc_context[ind].threshold =
 316                         intc_readl(INTC_THRESHOLD);
 317                 for (i = 0; i < INTCPS_NR_IRQS; i++)
 318                         intc_context[ind].ilr[i] =
 319                                 intc_readl((INTC_ILR0 + 0x4 * i));
 320                 for (i = 0; i < INTCPS_NR_MIR_REGS; i++)
 321                         intc_context[ind].mir[i] =
 322                                 intc_readl(INTC_MIR0 + (0x20 * i));
 323         }
 324 }
 325
 326 void omap_intc_restore_context(void)
 327 {
 328         int ind = 0, i = 0;
 329
 330         for (ind = 0; ind < ARRAY_SIZE(irq_banks); ind++) {
 331                 intc_writel(INTC_SYSCONFIG, intc_context[ind].sysconfig);
 332                 intc_writel(INTC_PROTECTION, intc_context[ind].protection);
 333                 intc_writel(INTC_IDLE, intc_context[ind].idle);
 334                 intc_writel(INTC_THRESHOLD, intc_context[ind].threshold);
 335                 for (i = 0; i < INTCPS_NR_IRQS; i++)
 336                         intc_writel(INTC_ILR0 + 0x4 * i,
 337                                         intc_context[ind].ilr[i]);
 338                 for (i = 0; i < INTCPS_NR_MIR_REGS; i++)
 339                         intc_writel(INTC_MIR0 + 0x20 * i,
 340                                 intc_context[ind].mir[i]);
 341         }
 342         /* MIRs are saved and restore with other PRCM registers */
 343 }
 344
 345 void omap3_intc_suspend(void)
 346 {
 347         /* A pending interrupt would prevent OMAP from entering suspend */
 348         omap_ack_irq(NULL);
 349 }
 350
 351 void omap3_intc_prepare_idle(void)
 352 {
 353         /*
 354          * Disable autoidle as it can stall interrupt controller,
 355          * cf. errata ID i540 for 3430 (all revisions up to 3.1.x)
 356          */
 357         intc_writel(INTC_SYSCONFIG, 0);
 358 }
 359
 360 void omap3_intc_resume_idle(void)
 361 {
 362         /* Re-enable autoidle */
 363         intc_writel(INTC_SYSCONFIG, 1);
 364 }
 365
 366 asmlinkage void __exception_irq_entry omap3_intc_handle_irq(struct pt_regs *regs)
 367 {
 368         void __iomem *base_addr = OMAP3_IRQ_BASE;
 369         omap_intc_handle_irq(base_addr, regs);
 370 }
 371 #endif /* CONFIG_ARCH_OMAP3 */