arch/h8300/kernel/irq.c

   1 /*
   2  * linux/arch/h8300/kernel/irq.c
   3  *
   4  * Copyright 2007 Yoshinori Sato <ysato@users.sourceforge.jp>
   5  */
   6
   7 #include <linux/module.h>
   8 #include <linux/types.h>
   9 #include <linux/kernel.h>
  10 #include <linux/sched.h>
  11 #include <linux/kernel_stat.h>
  12 #include <linux/seq_file.h>
  13 #include <linux/init.h>
  14 #include <linux/random.h>
  15 #include <linux/bootmem.h>
  16 #include <linux/irq.h>
  17 #include <linux/interrupt.h>
  18
  19 #include <asm/system.h>
  20 #include <asm/traps.h>
  21 #include <asm/io.h>
  22 #include <asm/setup.h>
  23 #include <asm/errno.h>
  24
  25 /*#define DEBUG*/
  26
  27 extern unsigned long *interrupt_redirect_table;
  28 extern const int h8300_saved_vectors[];
  29 extern const h8300_vector h8300_trap_table[];
  30 int h8300_enable_irq_pin(unsigned int irq);
  31 void h8300_disable_irq_pin(unsigned int irq);
  32
  33 #define CPU_VECTOR ((unsigned long *)0x000000)
  34 #define ADDR_MASK (0xffffff)
  35
  36 static inline int is_ext_irq(unsigned int irq)
  37 {
  38         return (irq >= EXT_IRQ0 && irq <= (EXT_IRQ0 + EXT_IRQS));
  39 }
  40
  41 static void h8300_enable_irq(unsigned int irq)
  42 {
  43         if (is_ext_irq(irq))
  44                 IER_REGS |= 1 << (irq - EXT_IRQ0);
  45 }
  46
  47 static void h8300_disable_irq(unsigned int irq)
  48 {
  49         if (is_ext_irq(irq))
  50                 IER_REGS &= ~(1 << (irq - EXT_IRQ0));
  51 }
  52
  53 static void h8300_end_irq(unsigned int irq)
  54 {
  55 }
  56
  57 static unsigned int h8300_startup_irq(unsigned int irq)
  58 {
  59         if (is_ext_irq(irq))
  60                 return h8300_enable_irq_pin(irq);
  61         else
  62                 return 0;
  63 }
  64
  65 static void h8300_shutdown_irq(unsigned int irq)
  66 {
  67         if (is_ext_irq(irq))
  68                 h8300_disable_irq_pin(irq);
  69 }
  70
  71 /*
  72  * h8300 interrupt controller implementation
  73  */
  74 struct irq_chip h8300irq_chip = {
  75         .name           = "H8300-INTC",
  76         .startup        = h8300_startup_irq,
  77         .shutdown       = h8300_shutdown_irq,
  78         .enable         = h8300_enable_irq,
  79         .disable        = h8300_disable_irq,
  80         .ack            = NULL,
  81         .end            = h8300_end_irq,
  82 };
  83
  84 void ack_bad_irq(unsigned int irq)
  85 {
  86         printk("unexpected IRQ trap at vector %02x\n", irq);
  87 }
  88
  89 #if defined(CONFIG_RAMKERNEL)
  90 static unsigned long __init *get_vector_address(void)
  91 {
  92         unsigned long *rom_vector = CPU_VECTOR;
  93         unsigned long base,tmp;
  94         int vec_no;
  95
  96         base = rom_vector[EXT_IRQ0] & ADDR_MASK;
  97
  98         /* check romvector format */
  99         for (vec_no = EXT_IRQ1; vec_no <= EXT_IRQ0+EXT_IRQS; vec_no++) {
 100                 if ((base+(vec_no - EXT_IRQ0)*4) != (rom_vector[vec_no] & ADDR_MASK))
 101                         return NULL;
 102         }
 103
 104         /* ramvector base address */
 105         base -= EXT_IRQ0*4;
 106
 107         /* writerble check */
 108         tmp = ~(*(volatile unsigned long *)base);
 109         (*(volatile unsigned long *)base) = tmp;
 110         if ((*(volatile unsigned long *)base) != tmp)
 111                 return NULL;
 112         return (unsigned long *)base;
 113 }
 114
 115 static void __init setup_vector(void)
 116 {
 117         int i;
 118         unsigned long *ramvec,*ramvec_p;
 119         const h8300_vector *trap_entry;
 120         const int *saved_vector;
 121
 122         ramvec = get_vector_address();
 123         if (ramvec == NULL)
 124                 panic("interrupt vector serup failed.");
 125         else
 126                 printk(KERN_INFO "virtual vector at 0x%08lx\n",(unsigned long)ramvec);
 127
 128         /* create redirect table */
 129         ramvec_p = ramvec;
 130         trap_entry = h8300_trap_table;
 131         saved_vector = h8300_saved_vectors;
 132         for ( i = 0; i < NR_IRQS; i++) {
 133                 if (i == *saved_vector) {
 134                         ramvec_p++;
 135                         saved_vector++;
 136                 } else {
 137                         if ( i < NR_TRAPS ) {
 138                                 if (*trap_entry)
 139                                         *ramvec_p = VECTOR(*trap_entry);
 140                                 ramvec_p++;
 141                                 trap_entry++;
 142                         } else
 143                                 *ramvec_p++ = REDIRECT(interrupt_entry);
 144                 }
 145         }
 146         interrupt_redirect_table = ramvec;
 147 #ifdef DEBUG
 148         ramvec_p = ramvec;
 149         for (i = 0; i < NR_IRQS; i++) {
 150                 if ((i % 8) == 0)
 151                         printk(KERN_DEBUG "\n%p: ",ramvec_p);
 152                 printk(KERN_DEBUG "%p ",*ramvec_p);
 153                 ramvec_p++;
 154         }
 155         printk(KERN_DEBUG "\n");
 156 #endif
 157 }
 158 #else
 159 #define setup_vector() do { } while(0)
 160 #endif
 161
 162 void __init init_IRQ(void)
 163 {
 164         int c;
 165
 166         setup_vector();
 167
 168         for (c = 0; c < NR_IRQS; c++) {
 169                 irq_desc[c].status = IRQ_DISABLED;
 170                 irq_desc[c].action = NULL;
 171                 irq_desc[c].depth = 1;
 172                 irq_desc[c].chip = &h8300irq_chip;
 173         }
 174 }
 175
 176 asmlinkage void do_IRQ(int irq)
 177 {
 178         irq_enter();
 179         __do_IRQ(irq);
 180         irq_exit();
 181 }
 182
 183 #if defined(CONFIG_PROC_FS)
 184 int show_interrupts(struct seq_file *p, void *v)
 185 {
 186         int i = *(loff_t *) v, j;
 187         struct irqaction * action;
 188         unsigned long flags;
 189
 190         if (i == 0)
 191                 seq_puts(p, "           CPU0");
 192
 193         if (i < NR_IRQS) {
 194                 spin_lock_irqsave(&irq_desc[i].lock, flags);
 195                 action = irq_desc[i].action;
 196                 if (!action)
 197                         goto unlock;
 198                 seq_printf(p, "%3d: ",i);
 199                 seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
 200                 seq_printf(p, " %14s", irq_desc[i].chip->name);
 201                 seq_printf(p, "-%-8s", irq_desc[i].name);
 202                 seq_printf(p, "  %s", action->name);
 203
 204                 for (action=action->next; action; action = action->next)
 205                         seq_printf(p, ", %s", action->name);
 206                 seq_putc(p, '\n');
 207 unlock:
 208                 spin_unlock_irqrestore(&irq_desc[i].lock, flags);
 209         }
 210         return 0;
 211 }
 212 #endif