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#ifndef _ASM_IRQ_H
#define _ASM_IRQ_H
/*
* linux/include/asm/irq.h
*
* (C) 1992, 1993 Linus Torvalds
*/
#include <linux/segment.h>
#include <linux/linkage.h>
extern void disable_irq(unsigned int);
extern void enable_irq(unsigned int);
#define __STR(x) #x
#define STR(x) __STR(x)
#define SAVE_ALL \
"cld\n\t" \
"push %gs\n\t" \
"push %fs\n\t" \
"push %es\n\t" \
"push %ds\n\t" \
"pushl %eax\n\t" \
"pushl %ebp\n\t" \
"pushl %edi\n\t" \
"pushl %esi\n\t" \
"pushl %edx\n\t" \
"pushl %ecx\n\t" \
"pushl %ebx\n\t" \
"movl $" STR(KERNEL_DS) ",%edx\n\t" \
"mov %dx,%ds\n\t" \
"mov %dx,%es\n\t" \
"movl $" STR(USER_DS) ",%edx\n\t" \
"mov %dx,%fs\n\t" \
"movl $0,%edx\n\t" \
"movl %edx,%db7\n\t"
/*
* SAVE_MOST/RESTORE_MOST is used for the faster version of IRQ handlers,
* installed by using the SA_INTERRUPT flag. These kinds of IRQ's don't
* call the routines that do signal handling etc on return, and can have
* more relaxed register-saving etc. They are also atomic, and are thus
* suited for small, fast interrupts like the serial lines or the harddisk
* drivers, which don't actually need signal handling etc.
*
* Also note that we actually save only those registers that are used in
* C subroutines (%eax, %edx and %ecx), so if you do something weird,
* you're on your own. The only segments that are saved (not counting the
* automatic stack and code segment handling) are %ds and %es, and they
* point to kernel space. No messing around with %fs here.
*/
#define SAVE_MOST \
"cld\n\t" \
"push %es\n\t" \
"push %ds\n\t" \
"pushl %eax\n\t" \
"pushl %edx\n\t" \
"pushl %ecx\n\t" \
"movl $" STR(KERNEL_DS) ",%edx\n\t" \
"mov %dx,%ds\n\t" \
"mov %dx,%es\n\t"
#define RESTORE_MOST \
"popl %ecx\n\t" \
"popl %edx\n\t" \
"popl %eax\n\t" \
"pop %ds\n\t" \
"pop %es\n\t" \
"iret"
/*
* The "inb" instructions are not needed, but seem to change the timings
* a bit - without them it seems that the harddisk driver won't work on
* all hardware. Arghh.
*/
#define ACK_FIRST(mask) \
"inb $0x21,%al\n\t" \
"jmp 1f\n" \
"1:\tjmp 1f\n" \
"1:\torb $" #mask ",_cache_21\n\t" \
"movb _cache_21,%al\n\t" \
"outb %al,$0x21\n\t" \
"jmp 1f\n" \
"1:\tjmp 1f\n" \
"1:\tmovb $0x20,%al\n\t" \
"outb %al,$0x20\n\t"
#define ACK_SECOND(mask) \
"inb $0xA1,%al\n\t" \
"jmp 1f\n" \
"1:\tjmp 1f\n" \
"1:\torb $" #mask ",_cache_A1\n\t" \
"movb _cache_A1,%al\n\t" \
"outb %al,$0xA1\n\t" \
"jmp 1f\n" \
"1:\tjmp 1f\n" \
"1:\tmovb $0x20,%al\n\t" \
"outb %al,$0xA0\n\t" \
"jmp 1f\n" \
"1:\tjmp 1f\n" \
"1:\toutb %al,$0x20\n\t"
#define UNBLK_FIRST(mask) \
"inb $0x21,%al\n\t" \
"jmp 1f\n" \
"1:\tjmp 1f\n" \
"1:\tandb $~(" #mask "),_cache_21\n\t" \
"movb _cache_21,%al\n\t" \
"outb %al,$0x21\n\t"
#define UNBLK_SECOND(mask) \
"inb $0xA1,%al\n\t" \
"jmp 1f\n" \
"1:\tjmp 1f\n" \
"1:\tandb $~(" #mask "),_cache_A1\n\t" \
"movb _cache_A1,%al\n\t" \
"outb %al,$0xA1\n\t"
#define IRQ_NAME2(nr) nr##_interrupt(void)
#define IRQ_NAME(nr) IRQ_NAME2(IRQ##nr)
#define FAST_IRQ_NAME(nr) IRQ_NAME2(fast_IRQ##nr)
#define BAD_IRQ_NAME(nr) IRQ_NAME2(bad_IRQ##nr)
#define BUILD_IRQ(chip,nr,mask) \
asmlinkage void IRQ_NAME(nr); \
asmlinkage void FAST_IRQ_NAME(nr); \
asmlinkage void BAD_IRQ_NAME(nr); \
__asm__( \
"\n.align 4\n" \
"_IRQ" #nr "_interrupt:\n\t" \
"pushl $-"#nr"-2\n\t" \
SAVE_ALL \
ACK_##chip(mask) \
"incl _intr_count\n\t"\
"sti\n\t" \
"movl %esp,%ebx\n\t" \
"pushl %ebx\n\t" \
"pushl $" #nr "\n\t" \
"call _do_IRQ\n\t" \
"addl $8,%esp\n\t" \
"cli\n\t" \
UNBLK_##chip(mask) \
"decl _intr_count\n\t" \
"jmp ret_from_sys_call\n" \
"\n.align 4\n" \
"_fast_IRQ" #nr "_interrupt:\n\t" \
SAVE_MOST \
ACK_##chip(mask) \
"incl _intr_count\n\t" \
"pushl $" #nr "\n\t" \
"call _do_fast_IRQ\n\t" \
"addl $4,%esp\n\t" \
"cli\n\t" \
UNBLK_##chip(mask) \
"decl _intr_count\n\t" \
RESTORE_MOST \
"\n\n.align 4\n" \
"_bad_IRQ" #nr "_interrupt:\n\t" \
SAVE_MOST \
ACK_##chip(mask) \
RESTORE_MOST);
#endif