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#ifndef _ASM_ARCH_IRQ_H
#define _ASM_ARCH_IRQ_H
#include <linux/config.h>
#include "hwregs/intr_vect.h"
/* Number of non-cpu interrupts. */
#define NR_IRQS 0x50 /* Exceptions + IRQs */
#define NR_REAL_IRQS 0x20 /* IRQs */
#define FIRST_IRQ 0x31 /* Exception number for first IRQ */
#ifndef __ASSEMBLY__
/* Global IRQ vector. */
typedef void (*irqvectptr)(void);
struct etrax_interrupt_vector {
irqvectptr v[256];
};
extern struct etrax_interrupt_vector *etrax_irv; /* head.S */
void mask_irq(int irq);
void unmask_irq(int irq);
void set_exception_vector(int n, irqvectptr addr);
/* Save registers so that they match pt_regs. */
#define SAVE_ALL \
"subq 12,$sp\n\t" \
"move $erp,[$sp]\n\t" \
"subq 4,$sp\n\t" \
"move $srp,[$sp]\n\t" \
"subq 4,$sp\n\t" \
"move $ccs,[$sp]\n\t" \
"subq 4,$sp\n\t" \
"move $spc,[$sp]\n\t" \
"subq 4,$sp\n\t" \
"move $mof,[$sp]\n\t" \
"subq 4,$sp\n\t" \
"move $srs,[$sp]\n\t" \
"subq 4,$sp\n\t" \
"move.d $acr,[$sp]\n\t" \
"subq 14*4,$sp\n\t" \
"movem $r13,[$sp]\n\t" \
"subq 4,$sp\n\t" \
"move.d $r10,[$sp]\n"
#define STR2(x) #x
#define STR(x) STR2(x)
#define IRQ_NAME2(nr) nr##_interrupt(void)
#define IRQ_NAME(nr) IRQ_NAME2(IRQ##nr)
/*
* The reason for setting the S-bit when debugging the kernel is that we want
* hardware breakpoints to remain active while we are in an exception handler.
* Note that we cannot simply copy S1, since we may come here from user-space,
* or any context where the S-bit wasn't set.
*/
#ifdef CONFIG_ETRAX_KGDB
#define KGDB_FIXUP \
"move $ccs, $r10\n\t" \
"or.d (1<<9), $r10\n\t" \
"move $r10, $ccs\n\t"
#else
#define KGDB_FIXUP ""
#endif
/*
* Make sure the causing IRQ is blocked, then call do_IRQ. After that, unblock
* and jump to ret_from_intr which is found in entry.S.
*
* The reason for blocking the IRQ is to allow an sti() before the handler,
* which will acknowledge the interrupt, is run. The actual blocking is made
* by crisv32_do_IRQ.
*/
#define BUILD_IRQ(nr, mask) \
void IRQ_NAME(nr); \
__asm__ ( \
".text\n\t" \
"IRQ" #nr "_interrupt:\n\t" \
SAVE_ALL \
KGDB_FIXUP \
"move.d "#nr",$r10\n\t" \
"move.d $sp,$r12\n\t" \
"jsr crisv32_do_IRQ\n\t" \
"moveq 1, $r11\n\t" \
"jump ret_from_intr\n\t" \
"nop\n\t");
/*
* This is subtle. The timer interrupt is crucial and it should not be disabled
* for too long. However, if it had been a normal interrupt as per BUILD_IRQ, it
* would have been BLOCK'ed, and then softirq's are run before we return here to
* UNBLOCK. If the softirq's take too much time to run, the timer irq won't run
* and the watchdog will kill us.
*
* Furthermore, if a lot of other irq's occur before we return here, the
* multiple_irq handler is run and it prioritizes the timer interrupt. However
* if we had BLOCK'edit here, we would not get the multiple_irq at all.
*
* The non-blocking here is based on the knowledge that the timer interrupt is
* registred as a fast interrupt (SA_INTERRUPT) so that we _know_ there will not
* be an sti() before the timer irq handler is run to acknowledge the interrupt.
*/
#define BUILD_TIMER_IRQ(nr, mask) \
void IRQ_NAME(nr); \
__asm__ ( \
".text\n\t" \
"IRQ" #nr "_interrupt:\n\t" \
SAVE_ALL \
KGDB_FIXUP \
"move.d "#nr",$r10\n\t" \
"move.d $sp,$r12\n\t" \
"jsr crisv32_do_IRQ\n\t" \
"moveq 0,$r11\n\t" \
"jump ret_from_intr\n\t" \
"nop\n\t");
#endif /* __ASSEMBLY__ */
#endif /* _ASM_ARCH_IRQ_H */
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