target/linux/adm5120-2.6/files/arch/mips/adm5120/irq.c

   1 /*
   2  *      Copyright (C) ADMtek Incorporated.
   3  *              Creator : daniell@admtek.com.tw
   4  *      Carsten Langgaard, carstenl@mips.com
   5  *      Copyright (C) 2000, 2001 MIPS Technologies, Inc.
   6  *      Copyright (C) 2001 Ralf Baechle
   7  *      Copyright (C) 2005 Jeroen Vreeken (pe1rxq@amsat.org)
   8  */
   9
  10 #include <linux/autoconf.h>
  11 #include <linux/init.h>
  12 #include <linux/kernel_stat.h>
  13 #include <linux/signal.h>
  14 #include <linux/sched.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/slab.h>
  17 #include <linux/random.h>
  18 #include <linux/pm.h>
  19
  20 #include <asm/irq.h>
  21 #include <asm/time.h>
  22 #include <asm/mipsregs.h>
  23 #include <asm/gdb-stub.h>
  24 #include <asm/irq_cpu.h>
  25
  26 #define MIPS_CPU_TIMER_IRQ 7
  27
  28 extern int setup_irq(unsigned int irq, struct irqaction *irqaction);
  29 extern irq_desc_t irq_desc[];
  30 extern asmlinkage void mipsIRQ(void);
  31
  32 int mips_int_lock(void);
  33 void mips_int_unlock(int);
  34
  35 unsigned int mips_counter_frequency;
  36
  37 #define ADM5120_INTC_REG(reg)   (*(volatile u32 *)(KSEG1ADDR(0x12200000+(reg))))
  38 #define ADM5120_INTC_STATUS     ADM5120_INTC_REG(0x00)
  39 #define ADM5120_INTC_ENABLE     ADM5120_INTC_REG(0x08)
  40 #define ADM5120_INTC_DISABLE    ADM5120_INTC_REG(0x0c)
  41 #define ADM5120_IRQ_MAX         9
  42 #define ADM5120_IRQ_MASK        0x3ff
  43
  44 void adm5120_hw0_irqdispatch(struct pt_regs *regs)
  45 {
  46         unsigned long intsrc;
  47         int i;
  48
  49         intsrc = ADM5120_INTC_STATUS & ADM5120_IRQ_MASK;
  50
  51         for (i = 0; intsrc; intsrc >>= 1, i++)
  52                 if (intsrc & 0x1)
  53                         do_IRQ(i);
  54                 else
  55                         spurious_interrupt();
  56 }
  57
  58 void mips_timer_interrupt(struct pt_regs *regs)
  59 {
  60         write_c0_compare(read_c0_count()+ mips_counter_frequency/HZ);
  61         ll_timer_interrupt(MIPS_CPU_TIMER_IRQ);
  62 }
  63
  64 /* Main interrupt dispatcher */
  65 asmlinkage void plat_irq_dispatch(struct pt_regs *regs)
  66 {
  67         unsigned int cp0_cause = read_c0_cause() & read_c0_status();
  68
  69         if (cp0_cause & CAUSEF_IP7) {
  70                 mips_timer_interrupt( regs);
  71         } else if (cp0_cause & CAUSEF_IP2) {
  72                 adm5120_hw0_irqdispatch( regs);
  73         }
  74 }
  75
  76 void enable_adm5120_irq(unsigned int irq)
  77 {
  78         int s;
  79
  80         /* Disable all interrupts (FIQ/IRQ) */
  81         s = mips_int_lock();
  82
  83         if ((irq < 0) || (irq > ADM5120_IRQ_MAX))
  84                 goto err_exit;
  85
  86         ADM5120_INTC_ENABLE = (1<<irq);
  87
  88 err_exit:
  89
  90         /* Restore the interrupts states */
  91         mips_int_unlock(s);
  92 }
  93
  94
  95 void disable_adm5120_irq(unsigned int irq)
  96 {
  97         int s;
  98
  99         /* Disable all interrupts (FIQ/IRQ) */
 100         s = mips_int_lock();
 101
 102         if ((irq < 0) || (irq > ADM5120_IRQ_MAX))
 103                 goto err_exit;
 104
 105         ADM5120_INTC_DISABLE = (1<<irq);
 106
 107 err_exit:
 108         /* Restore the interrupts states */
 109         mips_int_unlock(s);
 110 }
 111
 112 unsigned int startup_adm5120_irq(unsigned int irq)
 113 {
 114         enable_adm5120_irq(irq);
 115         return 0;
 116 }
 117
 118 void shutdown_adm5120_irq(unsigned int irq)
 119 {
 120         disable_adm5120_irq(irq);
 121 }
 122
 123 static inline void ack_adm5120_irq(unsigned int irq_nr)
 124 {
 125         ADM5120_INTC_DISABLE = (1 << irq_nr);
 126 }
 127
 128
 129 static void end_adm5120_irq(unsigned int irq_nr)
 130 {
 131         ADM5120_INTC_ENABLE = (1 << irq_nr);
 132 }
 133
 134 static hw_irq_controller adm5120_irq_type = {
 135         .typename       = "MIPS",
 136         .startup        = startup_adm5120_irq,
 137         .shutdown       = shutdown_adm5120_irq,
 138         .enable         = enable_adm5120_irq,
 139         .disable        = disable_adm5120_irq,
 140         .ack            = ack_adm5120_irq,
 141         .end            = end_adm5120_irq,
 142         .set_affinity   = NULL,
 143 };
 144
 145
 146 void __init arch_init_irq(void)
 147 {
 148         int i;
 149
 150         for (i = 0; i <= ADM5120_IRQ_MAX; i++) {
 151                 irq_desc[i].status = IRQ_DISABLED;
 152                 irq_desc[i].action = 0;
 153                 irq_desc[i].depth = 1;
 154                 irq_desc[i].chip = &adm5120_irq_type;
 155         }
 156 }