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/init.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/io.h>
  17 #include <mach/hardware.h>
  18 #include <asm/mach/irq.h>
  19
  20
  21 /* selected INTC register offsets */
  22
  23 #define INTC_REVISION           0x0000
  24 #define INTC_SYSCONFIG          0x0010
  25 #define INTC_SYSSTATUS          0x0014
  26 #define INTC_SIR                0x0040
  27 #define INTC_CONTROL            0x0048
  28 #define INTC_PROTECTION         0x004C
  29 #define INTC_IDLE               0x0050
  30 #define INTC_THRESHOLD          0x0068
  31 #define INTC_MIR0               0x0084
  32 #define INTC_MIR_CLEAR0         0x0088
  33 #define INTC_MIR_SET0           0x008c
  34 #define INTC_PENDING_IRQ0       0x0098
  35 /* Number of IRQ state bits in each MIR register */
  36 #define IRQ_BITS_PER_REG        32
  37
  38 /*
  39  * OMAP2 has a number of different interrupt controllers, each interrupt
  40  * controller is identified as its own "bank". Register definitions are
  41  * fairly consistent for each bank, but not all registers are implemented
  42  * for each bank.. when in doubt, consult the TRM.
  43  */
  44 static struct omap_irq_bank {
  45         void __iomem *base_reg;
  46         unsigned int nr_irqs;
  47 } __attribute__ ((aligned(4))) irq_banks[] = {
  48         {
  49                 /* MPU INTC */
  50                 .nr_irqs        = 96,
  51         },
  52 };
  53
  54 /* Structure to save interrupt controller context */
  55 struct omap3_intc_regs {
  56         u32 sysconfig;
  57         u32 protection;
  58         u32 idle;
  59         u32 threshold;
  60         u32 ilr[INTCPS_NR_IRQS];
  61         u32 mir[INTCPS_NR_MIR_REGS];
  62 };
  63
  64 /* INTC bank register get/set */
  65
  66 static void intc_bank_write_reg(u32 val, struct omap_irq_bank *bank, u16 reg)
  67 {
  68         __raw_writel(val, bank->base_reg + reg);
  69 }
  70
  71 static u32 intc_bank_read_reg(struct omap_irq_bank *bank, u16 reg)
  72 {
  73         return __raw_readl(bank->base_reg + reg);
  74 }
  75
  76 /* XXX: FIQ and additional INTC support (only MPU at the moment) */
  77 static void omap_ack_irq(struct irq_data *d)
  78 {
  79         intc_bank_write_reg(0x1, &irq_banks[0], INTC_CONTROL);
  80 }
  81
  82 static void omap_mask_ack_irq(struct irq_data *d)
  83 {
  84         irq_gc_mask_disable_reg(d);
  85         omap_ack_irq(d);
  86 }
  87
  88 static void __init omap_irq_bank_init_one(struct omap_irq_bank *bank)
  89 {
  90         unsigned long tmp;
  91
  92         tmp = intc_bank_read_reg(bank, INTC_REVISION) & 0xff;
  93         printk(KERN_INFO "IRQ: Found an INTC at 0x%p "
  94                          "(revision %ld.%ld) with %d interrupts\n",
  95                          bank->base_reg, tmp >> 4, tmp & 0xf, bank->nr_irqs);
  96
  97         tmp = intc_bank_read_reg(bank, INTC_SYSCONFIG);
  98         tmp |= 1 << 1;  /* soft reset */
  99         intc_bank_write_reg(tmp, bank, INTC_SYSCONFIG);
 100
 101         while (!(intc_bank_read_reg(bank, INTC_SYSSTATUS) & 0x1))
 102                 /* Wait for reset to complete */;
 103
 104         /* Enable autoidle */
 105         intc_bank_write_reg(1 << 0, bank, INTC_SYSCONFIG);
 106 }
 107
 108 int omap_irq_pending(void)
 109 {
 110         int i;
 111
 112         for (i = 0; i < ARRAY_SIZE(irq_banks); i++) {
 113                 struct omap_irq_bank *bank = irq_banks + i;
 114                 int irq;
 115
 116                 for (irq = 0; irq < bank->nr_irqs; irq += 32)
 117                         if (intc_bank_read_reg(bank, INTC_PENDING_IRQ0 +
 118                                                ((irq >> 5) << 5)))
 119                                 return 1;
 120         }
 121         return 0;
 122 }
 123
 124 static __init void
 125 omap_alloc_gc(void __iomem *base, unsigned int irq_start, unsigned int num)
 126 {
 127         struct irq_chip_generic *gc;
 128         struct irq_chip_type *ct;
 129
 130         gc = irq_alloc_generic_chip("INTC", 1, irq_start, base,
 131                                         handle_level_irq);
 132         ct = gc->chip_types;
 133         ct->chip.irq_ack = omap_mask_ack_irq;
 134         ct->chip.irq_mask = irq_gc_mask_disable_reg;
 135         ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
 136
 137         ct->regs.ack = INTC_CONTROL;
 138         ct->regs.enable = INTC_MIR_CLEAR0;
 139         ct->regs.disable = INTC_MIR_SET0;
 140         irq_setup_generic_chip(gc, IRQ_MSK(num), IRQ_GC_INIT_MASK_CACHE,
 141                                 IRQ_NOREQUEST | IRQ_NOPROBE, 0);
 142 }
 143
 144 void __init omap_init_irq(void)
 145 {
 146         unsigned long nr_of_irqs = 0;
 147         unsigned int nr_banks = 0;
 148         int i, j;
 149
 150         for (i = 0; i < ARRAY_SIZE(irq_banks); i++) {
 151                 unsigned long base = 0;
 152                 struct omap_irq_bank *bank = irq_banks + i;
 153
 154                 if (cpu_is_omap24xx())
 155                         base = OMAP24XX_IC_BASE;
 156                 else if (cpu_is_omap34xx())
 157                         base = OMAP34XX_IC_BASE;
 158
 159                 BUG_ON(!base);
 160
 161                 if (cpu_is_ti816x())
 162                         bank->nr_irqs = 128;
 163
 164                 /* Static mapping, never released */
 165                 bank->base_reg = ioremap(base, SZ_4K);
 166                 if (!bank->base_reg) {
 167                         printk(KERN_ERR "Could not ioremap irq bank%i\n", i);
 168                         continue;
 169                 }
 170
 171                 omap_irq_bank_init_one(bank);
 172
 173                 for (i = 0, j = 0; i < bank->nr_irqs; i += 32, j += 0x20)
 174                         omap_alloc_gc(bank->base_reg + j, i, 32);
 175
 176                 nr_of_irqs += bank->nr_irqs;
 177                 nr_banks++;
 178         }
 179
 180         printk(KERN_INFO "Total of %ld interrupts on %d active controller%s\n",
 181                nr_of_irqs, nr_banks, nr_banks > 1 ? "s" : "");
 182 }
 183
 184 #ifdef CONFIG_ARCH_OMAP3
 185 static struct omap3_intc_regs intc_context[ARRAY_SIZE(irq_banks)];
 186
 187 void omap_intc_save_context(void)
 188 {
 189         int ind = 0, i = 0;
 190         for (ind = 0; ind < ARRAY_SIZE(irq_banks); ind++) {
 191                 struct omap_irq_bank *bank = irq_banks + ind;
 192                 intc_context[ind].sysconfig =
 193                         intc_bank_read_reg(bank, INTC_SYSCONFIG);
 194                 intc_context[ind].protection =
 195                         intc_bank_read_reg(bank, INTC_PROTECTION);
 196                 intc_context[ind].idle =
 197                         intc_bank_read_reg(bank, INTC_IDLE);
 198                 intc_context[ind].threshold =
 199                         intc_bank_read_reg(bank, INTC_THRESHOLD);
 200                 for (i = 0; i < INTCPS_NR_IRQS; i++)
 201                         intc_context[ind].ilr[i] =
 202                                 intc_bank_read_reg(bank, (0x100 + 0x4*i));
 203                 for (i = 0; i < INTCPS_NR_MIR_REGS; i++)
 204                         intc_context[ind].mir[i] =
 205                                 intc_bank_read_reg(&irq_banks[0], INTC_MIR0 +
 206                                 (0x20 * i));
 207         }
 208 }
 209
 210 void omap_intc_restore_context(void)
 211 {
 212         int ind = 0, i = 0;
 213
 214         for (ind = 0; ind < ARRAY_SIZE(irq_banks); ind++) {
 215                 struct omap_irq_bank *bank = irq_banks + ind;
 216                 intc_bank_write_reg(intc_context[ind].sysconfig,
 217                                         bank, INTC_SYSCONFIG);
 218                 intc_bank_write_reg(intc_context[ind].sysconfig,
 219                                         bank, INTC_SYSCONFIG);
 220                 intc_bank_write_reg(intc_context[ind].protection,
 221                                         bank, INTC_PROTECTION);
 222                 intc_bank_write_reg(intc_context[ind].idle,
 223                                         bank, INTC_IDLE);
 224                 intc_bank_write_reg(intc_context[ind].threshold,
 225                                         bank, INTC_THRESHOLD);
 226                 for (i = 0; i < INTCPS_NR_IRQS; i++)
 227                         intc_bank_write_reg(intc_context[ind].ilr[i],
 228                                 bank, (0x100 + 0x4*i));
 229                 for (i = 0; i < INTCPS_NR_MIR_REGS; i++)
 230                         intc_bank_write_reg(intc_context[ind].mir[i],
 231                                  &irq_banks[0], INTC_MIR0 + (0x20 * i));
 232         }
 233         /* MIRs are saved and restore with other PRCM registers */
 234 }
 235
 236 void omap3_intc_suspend(void)
 237 {
 238         /* A pending interrupt would prevent OMAP from entering suspend */
 239         omap_ack_irq(0);
 240 }
 241
 242 void omap3_intc_prepare_idle(void)
 243 {
 244         /*
 245          * Disable autoidle as it can stall interrupt controller,
 246          * cf. errata ID i540 for 3430 (all revisions up to 3.1.x)
 247          */
 248         intc_bank_write_reg(0, &irq_banks[0], INTC_SYSCONFIG);
 249 }
 250
 251 void omap3_intc_resume_idle(void)
 252 {
 253         /* Re-enable autoidle */
 254         intc_bank_write_reg(1, &irq_banks[0], INTC_SYSCONFIG);
 255 }
 256 #endif /* CONFIG_ARCH_OMAP3 */