arch/cris/include/arch-v32/arch/irq.h

   1 #ifndef _ASM_ARCH_IRQ_H
   2 #define _ASM_ARCH_IRQ_H
   3
   4 #include <hwregs/intr_vect.h>
   5
   6 /* Number of non-cpu interrupts. */
   7 #define NR_IRQS (NBR_INTR_VECT + 256) /* Exceptions + IRQs */
   8 #define FIRST_IRQ 0x31 /* Exception number for first IRQ */
   9 #define NR_REAL_IRQS (NBR_INTR_VECT - FIRST_IRQ) /* IRQs */
  10 #if NR_REAL_IRQS > 32
  11 #define MACH_IRQS 64
  12 #else
  13 #define MACH_IRQS 32
  14 #endif
  15
  16 #ifndef __ASSEMBLY__
  17 /* Global IRQ vector. */
  18 typedef void (*irqvectptr)(void);
  19
  20 struct etrax_interrupt_vector {
  21         irqvectptr v[256];
  22 };
  23
  24 extern struct etrax_interrupt_vector *etrax_irv;        /* head.S */
  25
  26 void crisv32_mask_irq(int irq);
  27 void crisv32_unmask_irq(int irq);
  28
  29 void set_exception_vector(int n, irqvectptr addr);
  30
  31 /* Save registers so that they match pt_regs. */
  32 #define SAVE_ALL \
  33         "subq 12,$sp\n\t"       \
  34         "move $erp,[$sp]\n\t"   \
  35         "subq 4,$sp\n\t"        \
  36         "move $srp,[$sp]\n\t"   \
  37         "subq 4,$sp\n\t"        \
  38         "move $ccs,[$sp]\n\t"   \
  39         "subq 4,$sp\n\t"        \
  40         "move $spc,[$sp]\n\t"   \
  41         "subq 4,$sp\n\t"        \
  42         "move $mof,[$sp]\n\t"   \
  43         "subq 4,$sp\n\t"        \
  44         "move $srs,[$sp]\n\t"   \
  45         "subq 4,$sp\n\t"        \
  46         "move.d $acr,[$sp]\n\t" \
  47         "subq 14*4,$sp\n\t"     \
  48         "movem $r13,[$sp]\n\t"  \
  49         "subq 4,$sp\n\t"        \
  50         "move.d $r10,[$sp]\n"
  51
  52 #define STR2(x) #x
  53 #define STR(x) STR2(x)
  54
  55 #define IRQ_NAME2(nr) nr##_interrupt(void)
  56 #define IRQ_NAME(nr) IRQ_NAME2(IRQ##nr)
  57
  58 /*
  59  * The reason for setting the S-bit when debugging the kernel is that we want
  60  * hardware breakpoints to remain active while we are in an exception handler.
  61  * Note that we cannot simply copy S1, since we may come here from user-space,
  62  * or any context where the S-bit wasn't set.
  63  */
  64 #ifdef CONFIG_ETRAX_KGDB
  65 #define KGDB_FIXUP \
  66         "move $ccs, $r10\n\t"           \
  67         "or.d (1<<9), $r10\n\t"         \
  68         "move $r10, $ccs\n\t"
  69 #else
  70 #define KGDB_FIXUP ""
  71 #endif
  72
  73 /*
  74  * Make sure the causing IRQ is blocked, then call do_IRQ. After that, unblock
  75  * and jump to ret_from_intr which is found in entry.S.
  76  *
  77  * The reason for blocking the IRQ is to allow an sti() before the handler,
  78  * which will acknowledge the interrupt, is run. The actual blocking is made
  79  * by crisv32_do_IRQ.
  80  */
  81 #define BUILD_IRQ(nr)                   \
  82 void IRQ_NAME(nr);                      \
  83 __asm__ (                               \
  84         ".text\n\t"                     \
  85         "IRQ" #nr "_interrupt:\n\t"     \
  86         SAVE_ALL                        \
  87         KGDB_FIXUP                      \
  88         "move.d "#nr",$r10\n\t"         \
  89         "move.d $sp, $r12\n\t"          \
  90         "jsr crisv32_do_IRQ\n\t"        \
  91         "moveq 1, $r11\n\t"             \
  92         "jump ret_from_intr\n\t"        \
  93         "nop\n\t");
  94 /*
  95  * This is subtle. The timer interrupt is crucial and it should not be disabled
  96  * for too long. However, if it had been a normal interrupt as per BUILD_IRQ, it
  97  * would have been BLOCK'ed, and then softirq's are run before we return here to
  98  * UNBLOCK. If the softirq's take too much time to run, the timer irq won't run
  99  * and the watchdog will kill us.
 100  *
 101  * Furthermore, if a lot of other irq's occur before we return here, the
 102  * multiple_irq handler is run and it prioritizes the timer interrupt. However
 103  * if we had BLOCK'edit here, we would not get the multiple_irq at all.
 104  *
 105  * The non-blocking here is based on the knowledge that the timer interrupt runs
 106  * with interrupts disabled, and therefore there will not be an sti() before the
 107  * timer irq handler is run to acknowledge the interrupt.
 108  */
 109 #define BUILD_TIMER_IRQ(nr, mask)       \
 110 void IRQ_NAME(nr);                      \
 111 __asm__ (                               \
 112         ".text\n\t"                     \
 113         "IRQ" #nr "_interrupt:\n\t"     \
 114         SAVE_ALL                        \
 115         KGDB_FIXUP                      \
 116         "move.d "#nr",$r10\n\t"         \
 117         "move.d $sp,$r12\n\t"           \
 118         "jsr crisv32_do_IRQ\n\t"        \
 119         "moveq 0,$r11\n\t"              \
 120         "jump ret_from_intr\n\t"        \
 121         "nop\n\t");
 122
 123 #endif /* __ASSEMBLY__ */
 124 #endif /* _ASM_ARCH_IRQ_H */