arch/powerpc/sysdev/mv64x60_pic.c

   1 /*
   2  * Interrupt handling for Marvell mv64360/mv64460 host bridges (Discovery)
   3  *
   4  * Author: Dale Farnsworth <dale@farnsworth.org>
   5  *
   6  * 2007 (c) MontaVista, Software, Inc.  This file is licensed under
   7  * the terms of the GNU General Public License version 2.  This program
   8  * is licensed "as is" without any warranty of any kind, whether express
   9  * or implied.
  10  */
  11
  12 #include <linux/stddef.h>
  13 #include <linux/kernel.h>
  14 #include <linux/init.h>
  15 #include <linux/irq.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/spinlock.h>
  18
  19 #include <asm/byteorder.h>
  20 #include <asm/io.h>
  21 #include <asm/prom.h>
  22 #include <asm/irq.h>
  23
  24 #include "mv64x60.h"
  25
  26 /* Interrupt Controller Interface Registers */
  27 #define MV64X60_IC_MAIN_CAUSE_LO        0x0004
  28 #define MV64X60_IC_MAIN_CAUSE_HI        0x000c
  29 #define MV64X60_IC_CPU0_INTR_MASK_LO    0x0014
  30 #define MV64X60_IC_CPU0_INTR_MASK_HI    0x001c
  31 #define MV64X60_IC_CPU0_SELECT_CAUSE    0x0024
  32
  33 #define MV64X60_HIGH_GPP_GROUPS         0x0f000000
  34 #define MV64X60_SELECT_CAUSE_HIGH       0x40000000
  35
  36 /* General Purpose Pins Controller Interface Registers */
  37 #define MV64x60_GPP_INTR_CAUSE          0x0008
  38 #define MV64x60_GPP_INTR_MASK           0x000c
  39
  40 #define MV64x60_LEVEL1_LOW              0
  41 #define MV64x60_LEVEL1_HIGH             1
  42 #define MV64x60_LEVEL1_GPP              2
  43
  44 #define MV64x60_LEVEL1_MASK             0x00000060
  45 #define MV64x60_LEVEL1_OFFSET           5
  46
  47 #define MV64x60_LEVEL2_MASK             0x0000001f
  48
  49 #define MV64x60_NUM_IRQS                96
  50
  51 static DEFINE_SPINLOCK(mv64x60_lock);
  52
  53 static void __iomem *mv64x60_irq_reg_base;
  54 static void __iomem *mv64x60_gpp_reg_base;
  55
  56 /*
  57  * Interrupt Controller Handling
  58  *
  59  * The interrupt controller handles three groups of interrupts:
  60  *   main low:  IRQ0-IRQ31
  61  *   main high: IRQ32-IRQ63
  62  *   gpp:       IRQ64-IRQ95
  63  *
  64  * This code handles interrupts in two levels.  Level 1 selects the
  65  * interrupt group, and level 2 selects an IRQ within that group.
  66  * Each group has its own irq_chip structure.
  67  */
  68
  69 static u32 mv64x60_cached_low_mask;
  70 static u32 mv64x60_cached_high_mask = MV64X60_HIGH_GPP_GROUPS;
  71 static u32 mv64x60_cached_gpp_mask;
  72
  73 static struct irq_host *mv64x60_irq_host;
  74
  75 /*
  76  * mv64x60_chip_low functions
  77  */
  78
  79 static void mv64x60_mask_low(unsigned int virq)
  80 {
  81         int level2 = irq_map[virq].hwirq & MV64x60_LEVEL2_MASK;
  82         unsigned long flags;
  83
  84         spin_lock_irqsave(&mv64x60_lock, flags);
  85         mv64x60_cached_low_mask &= ~(1 << level2);
  86         out_le32(mv64x60_irq_reg_base + MV64X60_IC_CPU0_INTR_MASK_LO,
  87                  mv64x60_cached_low_mask);
  88         spin_unlock_irqrestore(&mv64x60_lock, flags);
  89         (void)in_le32(mv64x60_irq_reg_base + MV64X60_IC_CPU0_INTR_MASK_LO);
  90 }
  91
  92 static void mv64x60_unmask_low(unsigned int virq)
  93 {
  94         int level2 = irq_map[virq].hwirq & MV64x60_LEVEL2_MASK;
  95         unsigned long flags;
  96
  97         spin_lock_irqsave(&mv64x60_lock, flags);
  98         mv64x60_cached_low_mask |= 1 << level2;
  99         out_le32(mv64x60_irq_reg_base + MV64X60_IC_CPU0_INTR_MASK_LO,
 100                  mv64x60_cached_low_mask);
 101         spin_unlock_irqrestore(&mv64x60_lock, flags);
 102         (void)in_le32(mv64x60_irq_reg_base + MV64X60_IC_CPU0_INTR_MASK_LO);
 103 }
 104
 105 static struct irq_chip mv64x60_chip_low = {
 106         .name           = "mv64x60_low",
 107         .mask           = mv64x60_mask_low,
 108         .mask_ack       = mv64x60_mask_low,
 109         .unmask         = mv64x60_unmask_low,
 110 };
 111
 112 /*
 113  * mv64x60_chip_high functions
 114  */
 115
 116 static void mv64x60_mask_high(unsigned int virq)
 117 {
 118         int level2 = irq_map[virq].hwirq & MV64x60_LEVEL2_MASK;
 119         unsigned long flags;
 120
 121         spin_lock_irqsave(&mv64x60_lock, flags);
 122         mv64x60_cached_high_mask &= ~(1 << level2);
 123         out_le32(mv64x60_irq_reg_base + MV64X60_IC_CPU0_INTR_MASK_HI,
 124                  mv64x60_cached_high_mask);
 125         spin_unlock_irqrestore(&mv64x60_lock, flags);
 126         (void)in_le32(mv64x60_irq_reg_base + MV64X60_IC_CPU0_INTR_MASK_HI);
 127 }
 128
 129 static void mv64x60_unmask_high(unsigned int virq)
 130 {
 131         int level2 = irq_map[virq].hwirq & MV64x60_LEVEL2_MASK;
 132         unsigned long flags;
 133
 134         spin_lock_irqsave(&mv64x60_lock, flags);
 135         mv64x60_cached_high_mask |= 1 << level2;
 136         out_le32(mv64x60_irq_reg_base + MV64X60_IC_CPU0_INTR_MASK_HI,
 137                  mv64x60_cached_high_mask);
 138         spin_unlock_irqrestore(&mv64x60_lock, flags);
 139         (void)in_le32(mv64x60_irq_reg_base + MV64X60_IC_CPU0_INTR_MASK_HI);
 140 }
 141
 142 static struct irq_chip mv64x60_chip_high = {
 143         .name           = "mv64x60_high",
 144         .mask           = mv64x60_mask_high,
 145         .mask_ack       = mv64x60_mask_high,
 146         .unmask         = mv64x60_unmask_high,
 147 };
 148
 149 /*
 150  * mv64x60_chip_gpp functions
 151  */
 152
 153 static void mv64x60_mask_gpp(unsigned int virq)
 154 {
 155         int level2 = irq_map[virq].hwirq & MV64x60_LEVEL2_MASK;
 156         unsigned long flags;
 157
 158         spin_lock_irqsave(&mv64x60_lock, flags);
 159         mv64x60_cached_gpp_mask &= ~(1 << level2);
 160         out_le32(mv64x60_gpp_reg_base + MV64x60_GPP_INTR_MASK,
 161                  mv64x60_cached_gpp_mask);
 162         spin_unlock_irqrestore(&mv64x60_lock, flags);
 163         (void)in_le32(mv64x60_gpp_reg_base + MV64x60_GPP_INTR_MASK);
 164 }
 165
 166 static void mv64x60_mask_ack_gpp(unsigned int virq)
 167 {
 168         int level2 = irq_map[virq].hwirq & MV64x60_LEVEL2_MASK;
 169         unsigned long flags;
 170
 171         spin_lock_irqsave(&mv64x60_lock, flags);
 172         mv64x60_cached_gpp_mask &= ~(1 << level2);
 173         out_le32(mv64x60_gpp_reg_base + MV64x60_GPP_INTR_MASK,
 174                  mv64x60_cached_gpp_mask);
 175         out_le32(mv64x60_gpp_reg_base + MV64x60_GPP_INTR_CAUSE,
 176                  ~(1 << level2));
 177         spin_unlock_irqrestore(&mv64x60_lock, flags);
 178         (void)in_le32(mv64x60_gpp_reg_base + MV64x60_GPP_INTR_CAUSE);
 179 }
 180
 181 static void mv64x60_unmask_gpp(unsigned int virq)
 182 {
 183         int level2 = irq_map[virq].hwirq & MV64x60_LEVEL2_MASK;
 184         unsigned long flags;
 185
 186         spin_lock_irqsave(&mv64x60_lock, flags);
 187         mv64x60_cached_gpp_mask |= 1 << level2;
 188         out_le32(mv64x60_gpp_reg_base + MV64x60_GPP_INTR_MASK,
 189                  mv64x60_cached_gpp_mask);
 190         spin_unlock_irqrestore(&mv64x60_lock, flags);
 191         (void)in_le32(mv64x60_gpp_reg_base + MV64x60_GPP_INTR_MASK);
 192 }
 193
 194 static struct irq_chip mv64x60_chip_gpp = {
 195         .name           = "mv64x60_gpp",
 196         .mask           = mv64x60_mask_gpp,
 197         .mask_ack       = mv64x60_mask_ack_gpp,
 198         .unmask         = mv64x60_unmask_gpp,
 199 };
 200
 201 /*
 202  * mv64x60_host_ops functions
 203  */
 204
 205 static struct irq_chip *mv64x60_chips[] = {
 206         [MV64x60_LEVEL1_LOW]  = &mv64x60_chip_low,
 207         [MV64x60_LEVEL1_HIGH] = &mv64x60_chip_high,
 208         [MV64x60_LEVEL1_GPP]  = &mv64x60_chip_gpp,
 209 };
 210
 211 static int mv64x60_host_map(struct irq_host *h, unsigned int virq,
 212                           irq_hw_number_t hwirq)
 213 {
 214         int level1;
 215
 216         get_irq_desc(virq)->status |= IRQ_LEVEL;
 217
 218         level1 = (hwirq & MV64x60_LEVEL1_MASK) >> MV64x60_LEVEL1_OFFSET;
 219         BUG_ON(level1 > MV64x60_LEVEL1_GPP);
 220         set_irq_chip_and_handler(virq, mv64x60_chips[level1], handle_level_irq);
 221
 222         return 0;
 223 }
 224
 225 static struct irq_host_ops mv64x60_host_ops = {
 226         .map   = mv64x60_host_map,
 227 };
 228
 229 /*
 230  * Global functions
 231  */
 232
 233 void __init mv64x60_init_irq(void)
 234 {
 235         struct device_node *np;
 236         phys_addr_t paddr;
 237         unsigned int size;
 238         const unsigned int *reg;
 239         unsigned long flags;
 240
 241         np = of_find_compatible_node(NULL, NULL, "marvell,mv64x60-gpp");
 242         reg = of_get_property(np, "reg", &size);
 243         paddr = of_translate_address(np, reg);
 244         mv64x60_gpp_reg_base = ioremap(paddr, reg[1]);
 245         of_node_put(np);
 246
 247         np = of_find_compatible_node(NULL, NULL, "marvell,mv64x60-pic");
 248         reg = of_get_property(np, "reg", &size);
 249         paddr = of_translate_address(np, reg);
 250         mv64x60_irq_reg_base = ioremap(paddr, reg[1]);
 251
 252         mv64x60_irq_host = irq_alloc_host(np, IRQ_HOST_MAP_LINEAR,
 253                                           MV64x60_NUM_IRQS,
 254                                           &mv64x60_host_ops, MV64x60_NUM_IRQS);
 255
 256         spin_lock_irqsave(&mv64x60_lock, flags);
 257         out_le32(mv64x60_gpp_reg_base + MV64x60_GPP_INTR_MASK,
 258                  mv64x60_cached_gpp_mask);
 259         out_le32(mv64x60_irq_reg_base + MV64X60_IC_CPU0_INTR_MASK_LO,
 260                  mv64x60_cached_low_mask);
 261         out_le32(mv64x60_irq_reg_base + MV64X60_IC_CPU0_INTR_MASK_HI,
 262                  mv64x60_cached_high_mask);
 263
 264         out_le32(mv64x60_gpp_reg_base + MV64x60_GPP_INTR_CAUSE, 0);
 265         out_le32(mv64x60_irq_reg_base + MV64X60_IC_MAIN_CAUSE_LO, 0);
 266         out_le32(mv64x60_irq_reg_base + MV64X60_IC_MAIN_CAUSE_HI, 0);
 267         spin_unlock_irqrestore(&mv64x60_lock, flags);
 268 }
 269
 270 unsigned int mv64x60_get_irq(void)
 271 {
 272         u32 cause;
 273         int level1;
 274         irq_hw_number_t hwirq;
 275         int virq = NO_IRQ;
 276
 277         cause = in_le32(mv64x60_irq_reg_base + MV64X60_IC_CPU0_SELECT_CAUSE);
 278         if (cause & MV64X60_SELECT_CAUSE_HIGH) {
 279                 cause &= mv64x60_cached_high_mask;
 280                 level1 = MV64x60_LEVEL1_HIGH;
 281                 if (cause & MV64X60_HIGH_GPP_GROUPS) {
 282                         cause = in_le32(mv64x60_gpp_reg_base +
 283                                         MV64x60_GPP_INTR_CAUSE);
 284                         cause &= mv64x60_cached_gpp_mask;
 285                         level1 = MV64x60_LEVEL1_GPP;
 286                 }
 287         } else {
 288                 cause &= mv64x60_cached_low_mask;
 289                 level1 = MV64x60_LEVEL1_LOW;
 290         }
 291         if (cause) {
 292                 hwirq = (level1 << MV64x60_LEVEL1_OFFSET) | __ilog2(cause);
 293                 virq = irq_linear_revmap(mv64x60_irq_host, hwirq);
 294         }
 295
 296         return virq;
 297 }