target/linux/aruba-2.6/files/arch/mips/aruba/irq.c

   1 #include <linux/errno.h>
   2 #include <linux/init.h>
   3 #include <linux/kernel_stat.h>
   4 #include <linux/module.h>
   5 #include <linux/signal.h>
   6 #include <linux/sched.h>
   7 #include <linux/types.h>
   8 #include <linux/interrupt.h>
   9 #include <linux/ioport.h>
  10 #include <linux/timex.h>
  11 #include <linux/slab.h>
  12 #include <linux/random.h>
  13 #include <linux/delay.h>
  14
  15 #include <asm/bitops.h>
  16 #include <asm/bootinfo.h>
  17 #include <asm/io.h>
  18 #include <asm/mipsregs.h>
  19 #include <asm/system.h>
  20 #include <asm/idt-boards/rc32434/rc32434.h>
  21 #include <asm/idt-boards/rc32434/rc32434_gpio.h>
  22
  23 #include <asm/irq.h>
  24
  25 extern void aruba_timer_interrupt(struct pt_regs *regs);
  26
  27 typedef struct {
  28         u32 mask;
  29         volatile u32 *base_addr;
  30 } intr_group_t;
  31
  32 static const intr_group_t intr_group_merlot[NUM_INTR_GROUPS] = {
  33         {0x00000000, (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 0)},
  34 };
  35
  36 #define READ_PEND_MERLOT(base) (*((volatile unsigned long *)(0xbc003010)))
  37 #define READ_MASK_MERLOT(base) (*((volatile unsigned long *)(0xbc003014)))
  38 #define WRITE_MASK_MERLOT(base, val) ((*((volatile unsigned long *)(0xbc003014))) = (val), READ_MASK_MERLOT())
  39
  40 static const intr_group_t intr_group_muscat[NUM_INTR_GROUPS] = {
  41         {0x0000efff, (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 0 * IC_GROUP_OFFSET)},
  42         {0x00001fff, (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 1 * IC_GROUP_OFFSET)},
  43         {0x00000007, (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 2 * IC_GROUP_OFFSET)},
  44         {0x0003ffff, (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 3 * IC_GROUP_OFFSET)},
  45         {0xffffffff, (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 4 * IC_GROUP_OFFSET)}
  46 };
  47
  48 #define READ_PEND_MUSCAT(base) (*(base))
  49 #define READ_MASK_MUSCAT(base) (*(base + 2))
  50 #define WRITE_MASK_MUSCAT(base, val) (*(base + 2) = (val))
  51
  52 static inline int group_to_ip(unsigned int group)
  53 {
  54         switch (mips_machtype) {
  55                 case MACH_ARUBA_AP70:
  56                         return group + 2;
  57                 case MACH_ARUBA_AP65:
  58                 case MACH_ARUBA_AP60:
  59                 default:
  60                         return 6;
  61         }
  62 }
  63
  64 static inline void enable_local_irq(unsigned int irq)
  65 {
  66         clear_c0_cause(0x100 << irq);
  67         set_c0_status(0x100 << irq);
  68         irq_enable_hazard();
  69 }
  70
  71 static inline void disable_local_irq(unsigned int irq)
  72 {
  73         clear_c0_status(0x100 << irq);
  74         clear_c0_cause(0x100 << irq);
  75         irq_disable_hazard();
  76 }
  77
  78 static inline void aruba_irq_enable(unsigned int irq)
  79 {
  80         unsigned long flags;
  81         unsigned int  group, intr_bit;
  82         volatile unsigned int  *addr;
  83
  84         local_irq_save(flags);
  85
  86         if (irq < GROUP0_IRQ_BASE) {
  87                 enable_local_irq(irq);
  88         } else {
  89                 int ip = irq - GROUP0_IRQ_BASE;
  90                 switch (mips_machtype) {
  91                         case MACH_ARUBA_AP70:
  92                                 if (irq >= GROUP4_IRQ_BASE)
  93                                         idt_gpio->gpioistat &= ~(1 << (irq - GROUP4_IRQ_BASE));
  94
  95                                 // irqs are in groups of 32
  96                                 // ip is set to the remainder
  97                                 group = ip >> 5;
  98                                 ip &= 0x1f;
  99
 100                                 // bit -> 0 = unmask
 101                                 intr_bit = 1 << ip;
 102                                 addr = intr_group_muscat[group].base_addr;
 103                                 WRITE_MASK_MUSCAT(addr, READ_MASK_MUSCAT(addr) & ~intr_bit);
 104                                 break;
 105
 106                         case MACH_ARUBA_AP65:
 107                         case MACH_ARUBA_AP60:
 108                                 group = 0;
 109
 110                                 // bit -> 1 = unmasked
 111                                 intr_bit = 1 << ip;
 112                                 addr = intr_group_merlot[group].base_addr;
 113                                 WRITE_MASK_MERLOT(addr, READ_MASK_MERLOT(addr) | intr_bit);
 114                                 break;
 115                 }
 116                 enable_local_irq(group_to_ip(group));
 117         }
 118
 119         back_to_back_c0_hazard();
 120         local_irq_restore(flags);
 121 }
 122
 123 static void aruba_irq_disable(unsigned int irq)
 124 {
 125         unsigned long flags;
 126         unsigned int  group, intr_bit, mask;
 127         volatile unsigned int  *addr;
 128
 129         local_irq_save(flags);
 130
 131         if (irq < GROUP0_IRQ_BASE) {
 132                 disable_local_irq(irq);
 133         } else {
 134                 int ip = irq - GROUP0_IRQ_BASE;
 135                 switch (mips_machtype) {
 136                         case MACH_ARUBA_AP70:
 137                                 idt_gpio->gpioistat &= ~(1 << ip);
 138
 139                                 // irqs are in groups of 32
 140                                 // ip is set to the remainder
 141                                 group = ip >> 5;
 142                                 ip &= 0x1f;
 143
 144                                 // bit -> 1 = mask
 145                                 intr_bit = 1 << ip;
 146                                 addr = intr_group_muscat[group].base_addr;
 147
 148                                 mask = READ_MASK_MUSCAT(addr);
 149                                 mask |= intr_bit;
 150                                 WRITE_MASK_MUSCAT(addr, mask);
 151
 152                                 if (mask == intr_group_muscat[group].mask) {
 153                                         disable_local_irq(group_to_ip(group));
 154                                 }
 155                                 break;
 156
 157                         case MACH_ARUBA_AP65:
 158                         case MACH_ARUBA_AP60:
 159                                 group = 0;
 160
 161                                 // bit -> 0 = masked
 162                                 intr_bit = 1 << ip;
 163                                 addr = intr_group_merlot[group].base_addr;
 164
 165                                 mask = READ_MASK_MERLOT(addr);
 166                                 mask &= ~intr_bit;
 167                                 WRITE_MASK_MERLOT(addr, mask);
 168
 169                                 if (mask == intr_group_merlot[group].mask) {
 170                                         disable_local_irq(group_to_ip(group));
 171                                 }
 172                                 break;
 173                 }
 174         }
 175
 176         back_to_back_c0_hazard();
 177         local_irq_restore(flags);
 178 }
 179
 180 static unsigned int aruba_irq_startup(unsigned int irq)
 181 {
 182         aruba_irq_enable(irq);
 183         return 0;
 184 }
 185
 186 #define aruba_irq_shutdown aruba_irq_disable
 187
 188 static void aruba_irq_ack(unsigned int irq)
 189 {
 190         aruba_irq_disable(irq);
 191 }
 192
 193 static void aruba_irq_end(unsigned int irq)
 194 {
 195         if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS)))
 196                 aruba_irq_enable(irq);
 197 }
 198
 199 static struct hw_interrupt_type aruba_irq_type = {
 200         .typename       = "ARUBA",
 201         .startup        = aruba_irq_startup,
 202         .shutdown       = aruba_irq_shutdown,
 203         .enable         = aruba_irq_enable,
 204         .disable        = aruba_irq_disable,
 205         .ack            = aruba_irq_ack,
 206         .end            = aruba_irq_end,
 207 };
 208
 209 void __init arch_init_irq(void)
 210 {
 211         int i;
 212         printk("Initializing IRQ's: %d out of %d\n", RC32434_NR_IRQS, NR_IRQS);
 213         memset(irq_desc, 0, sizeof(irq_desc));
 214
 215         for (i = 0; i < RC32434_NR_IRQS; i++) {
 216                 irq_desc[i].status = IRQ_DISABLED;
 217                 irq_desc[i].action = NULL;
 218                 irq_desc[i].depth = 1;
 219                 irq_desc[i].chip = &aruba_irq_type;
 220                 spin_lock_init(&irq_desc[i].lock);
 221         }
 222 }
 223
 224 /* Main Interrupt dispatcher */
 225
 226 void plat_irq_dispatch(struct pt_regs *regs)
 227 {
 228         unsigned int pend, group, ip;
 229         volatile unsigned int *addr;
 230         unsigned long cp0_cause = read_c0_cause() & read_c0_status() & CAUSEF_IP;
 231
 232         if (cp0_cause & CAUSEF_IP7)
 233                 return aruba_timer_interrupt(regs);
 234
 235         if(cp0_cause == 0) {
 236                 printk("INTERRUPT(S) FIRED WHILE MASKED\n");
 237 #ifdef ARUBA_DEBUG
 238                 // debuging use -- figure out which interrupt(s) fired
 239                 cp0_cause = read_c0_cause() & CAUSEF_IP;
 240                 while (cp0_cause) {
 241                         unsigned long intr_bit;
 242                         unsigned int irq_nr;
 243                         intr_bit = (31 - rc32434_clz(cp0_cause));
 244                         irq_nr = intr_bit - GROUP0_IRQ_BASE;
 245                         printk(" ---> MASKED IRQ %d\n",irq_nr);
 246                         cp0_cause &= ~(1 << intr_bit);
 247                 }
 248 #endif
 249                 return;
 250         }
 251
 252         switch (mips_machtype) {
 253                 case MACH_ARUBA_AP70:
 254                         if ((ip = (cp0_cause & 0x7c00))) {
 255                                 group = 21 - rc32434_clz(ip);
 256
 257                                 addr = intr_group_muscat[group].base_addr;
 258
 259                                 pend = READ_PEND_MUSCAT(addr);
 260                                 pend &= ~READ_MASK_MUSCAT(addr); // only unmasked interrupts
 261                                 pend = 39 - rc32434_clz(pend);
 262                                 do_IRQ(pend + (group << 5));
 263                         }
 264                         break;
 265                 case MACH_ARUBA_AP65:
 266                 case MACH_ARUBA_AP60:
 267                 default:
 268                         if (cp0_cause & 0x4000) { // 1 << (8 +6) == irq 6
 269                                 // Misc Interrupt
 270                                 group = 0;
 271
 272                                 addr = intr_group_merlot[group].base_addr;
 273
 274                                 pend = READ_PEND_MERLOT(addr);
 275                                 pend &= READ_MASK_MERLOT(addr); // only unmasked interrupts
 276                                 pend = 31 - rc32434_clz(pend);
 277                                 do_IRQ(pend + GROUP0_IRQ_BASE);
 278                         }
 279                         if ((ip = (cp0_cause & 0x3c00))) { // irq 2-5
 280                                 pend = 31 - rc32434_clz(ip);
 281                                 do_IRQ(pend - GROUP0_IRQ_BASE);
 282                         }
 283                         break;
 284         }
 285 }