patch-2.1.35 linux/arch/i386/kernel/irq.h

• Lines: 270
• Date: Tue Apr 15 11:50:30 1997
• Orig file: v2.1.34/linux/arch/i386/kernel/irq.h
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.1.34/linux/arch/i386/kernel/irq.h linux/arch/i386/kernel/irq.h
@@ -0,0 +1,269 @@
+#ifndef __irq_h
+#define __irq_h
+
+/*
+ * Various low-level irq details needed by irq.c and smp.c
+ *
+ * Interrupt entry/exit code at both C and assembly level
+ */
+
+#ifdef __SMP__
+
+#undef INIT_STUCK
+#define INIT_STUCK 200000000
+
+#undef STUCK
+#define STUCK \
+if (!--stuck) {printk("irq_enter stuck (irq=%d, cpu=%d, global=%d)\n",irq,cpu,global_irq_holder); stuck = INIT_STUCK;}
+
+static inline void irq_enter(int cpu, int irq)
+{
+	int stuck = INIT_STUCK;
+
+	hardirq_enter(cpu);
+	while (test_bit(0,&global_irq_lock)) {
+		if ((unsigned char) cpu == global_irq_holder) {
+			printk("BAD! Local interrupts enabled, global disabled\n");
+			break;
+		}
+		STUCK;
+		/* nothing */;
+	}
+}
+
+static inline void irq_exit(int cpu, int irq)
+{
+	__cli();
+	hardirq_exit(cpu);
+	release_irqlock(cpu);
+}
+
+#else
+
+#define irq_enter(cpu, irq)	(++local_irq_count[cpu])
+#define irq_exit(cpu, irq)	(--local_irq_count[cpu])
+
+#endif
+
+#define __STR(x) #x
+#define STR(x) __STR(x)
+
+#define SAVE_ALL \
+	"cld\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"
+
+/*
+ * 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"
+
+/*
+ * Some fast irq handlers might want to access saved registers (mostly
+ * cs or flags)
+ */
+
+struct fast_irq_regs {
+	long ecx;
+	long edx;
+	long eax;
+	int  xds;
+	int  xes;
+	long eip;
+	int  xcs;
+	long eflags;
+	long esp;
+	int  xss;
+};
+
+/*
+ * 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,nr) \
+	"inb $0x21,%al\n\t" \
+	"jmp 1f\n" \
+	"1:\tjmp 1f\n" \
+	"1:\torb $" #mask ","SYMBOL_NAME_STR(cache_21)"\n\t" \
+	"movb "SYMBOL_NAME_STR(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,nr) \
+	"inb $0xA1,%al\n\t" \
+	"jmp 1f\n" \
+	"1:\tjmp 1f\n" \
+	"1:\torb $" #mask ","SYMBOL_NAME_STR(cache_A1)"\n\t" \
+	"movb "SYMBOL_NAME_STR(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 "),"SYMBOL_NAME_STR(cache_21)"\n\t" \
+	"movb "SYMBOL_NAME_STR(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 "),"SYMBOL_NAME_STR(cache_A1)"\n\t" \
+	"movb "SYMBOL_NAME_STR(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)
+
+#ifdef	__SMP__
+
+#define GET_CURRENT \
+	"movl "SYMBOL_NAME_STR(apic_reg)", %ebx\n\t" \
+	"movl 32(%ebx), %ebx\n\t" \
+	"shrl $22,%ebx\n\t" \
+	"andl $0x3C,%ebx\n\t" \
+	"movl " SYMBOL_NAME_STR(current_set) "(,%ebx),%ebx\n\t"
+	
+#else
+
+#define GET_CURRENT \
+	"movl " SYMBOL_NAME_STR(current_set) ",%ebx\n\t"
+	
+#endif
+
+#ifdef __SMP__
+
+/*
+ *	SMP has a few special interrupts for IPI messages
+ */
+
+#define BUILD_SMP_INTERRUPT(x) \
+asmlinkage void x(void); \
+__asm__( \
+"\n"__ALIGN_STR"\n" \
+SYMBOL_NAME_STR(x) ":\n\t" \
+	"pushl $-1\n\t" \
+	SAVE_ALL \
+	"call "SYMBOL_NAME_STR(smp_##x)"\n\t" \
+	"jmp ret_from_intr\n");
+
+#define BUILD_SMP_TIMER_INTERRUPT(x) \
+asmlinkage void x(struct pt_regs * regs); \
+__asm__( \
+"\n"__ALIGN_STR"\n" \
+SYMBOL_NAME_STR(x) ":\n\t" \
+	"pushl $-1\n\t" \
+        SAVE_ALL \
+        "movl %esp,%eax\n\t" \
+        "pushl %eax\n\t" \
+	"call "SYMBOL_NAME_STR(smp_##x)"\n\t" \
+        "addl $4,%esp\n\t" \
+	"jmp ret_from_intr\n");
+
+#endif /* __SMP__ */
+
+#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_STR"\n" \
+SYMBOL_NAME_STR(IRQ) #nr "_interrupt:\n\t" \
+	"pushl $-"#nr"-2\n\t" \
+	SAVE_ALL \
+	ACK_##chip(mask,(nr&7)) \
+	"movl %esp,%eax\n\t" \
+	"pushl %eax\n\t" \
+	"pushl $" #nr "\n\t" \
+	"call "SYMBOL_NAME_STR(do_IRQ)"\n\t" \
+	"addl $8,%esp\n\t" \
+	UNBLK_##chip(mask) \
+	"jmp ret_from_intr\n" \
+"\n"__ALIGN_STR"\n" \
+SYMBOL_NAME_STR(fast_IRQ) #nr "_interrupt:\n\t" \
+	SAVE_MOST \
+	ACK_##chip(mask,(nr&7)) \
+	"pushl $" #nr "\n\t" \
+	"call "SYMBOL_NAME_STR(do_fast_IRQ)"\n\t" \
+	"addl $4,%esp\n\t" \
+	UNBLK_##chip(mask) \
+	RESTORE_MOST \
+"\n"__ALIGN_STR"\n" \
+SYMBOL_NAME_STR(bad_IRQ) #nr "_interrupt:\n\t" \
+	SAVE_MOST \
+	ACK_##chip(mask,(nr&7)) \
+	RESTORE_MOST);
+	
+#define BUILD_TIMER_IRQ(chip,nr,mask) \
+asmlinkage void IRQ_NAME(nr); \
+asmlinkage void FAST_IRQ_NAME(nr); \
+asmlinkage void BAD_IRQ_NAME(nr); \
+__asm__( \
+"\n"__ALIGN_STR"\n" \
+SYMBOL_NAME_STR(fast_IRQ) #nr "_interrupt:\n\t" \
+SYMBOL_NAME_STR(bad_IRQ) #nr "_interrupt:\n\t" \
+SYMBOL_NAME_STR(IRQ) #nr "_interrupt:\n\t" \
+	"pushl $-"#nr"-2\n\t" \
+	SAVE_ALL \
+	ACK_##chip(mask,(nr&7)) \
+	"movl %esp,%eax\n\t" \
+	"pushl %eax\n\t" \
+	"pushl $" #nr "\n\t" \
+	"call "SYMBOL_NAME_STR(do_IRQ)"\n\t" \
+	"addl $8,%esp\n\t" \
+	UNBLK_##chip(mask) \
+	"jmp ret_from_intr\n");
+
+#endif