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Diffstat (limited to 'arch/x86/include/asm/i8259.h')
-rw-r--r--arch/x86/include/asm/i8259.h63
1 files changed, 63 insertions, 0 deletions
diff --git a/arch/x86/include/asm/i8259.h b/arch/x86/include/asm/i8259.h
new file mode 100644
index 00000000000..58d7091eeb1
--- /dev/null
+++ b/arch/x86/include/asm/i8259.h
@@ -0,0 +1,63 @@
+#ifndef _ASM_X86_I8259_H
+#define _ASM_X86_I8259_H
+
+#include <linux/delay.h>
+
+extern unsigned int cached_irq_mask;
+
+#define __byte(x, y) (((unsigned char *)&(y))[x])
+#define cached_master_mask (__byte(0, cached_irq_mask))
+#define cached_slave_mask (__byte(1, cached_irq_mask))
+
+/* i8259A PIC registers */
+#define PIC_MASTER_CMD 0x20
+#define PIC_MASTER_IMR 0x21
+#define PIC_MASTER_ISR PIC_MASTER_CMD
+#define PIC_MASTER_POLL PIC_MASTER_ISR
+#define PIC_MASTER_OCW3 PIC_MASTER_ISR
+#define PIC_SLAVE_CMD 0xa0
+#define PIC_SLAVE_IMR 0xa1
+
+/* i8259A PIC related value */
+#define PIC_CASCADE_IR 2
+#define MASTER_ICW4_DEFAULT 0x01
+#define SLAVE_ICW4_DEFAULT 0x01
+#define PIC_ICW4_AEOI 2
+
+extern spinlock_t i8259A_lock;
+
+extern void init_8259A(int auto_eoi);
+extern void enable_8259A_irq(unsigned int irq);
+extern void disable_8259A_irq(unsigned int irq);
+extern unsigned int startup_8259A_irq(unsigned int irq);
+
+/* the PIC may need a careful delay on some platforms, hence specific calls */
+static inline unsigned char inb_pic(unsigned int port)
+{
+ unsigned char value = inb(port);
+
+ /*
+ * delay for some accesses to PIC on motherboard or in chipset
+ * must be at least one microsecond, so be safe here:
+ */
+ udelay(2);
+
+ return value;
+}
+
+static inline void outb_pic(unsigned char value, unsigned int port)
+{
+ outb(value, port);
+ /*
+ * delay for some accesses to PIC on motherboard or in chipset
+ * must be at least one microsecond, so be safe here:
+ */
+ udelay(2);
+}
+
+extern struct irq_chip i8259A_chip;
+
+extern void mask_8259A(void);
+extern void unmask_8259A(void);
+
+#endif /* _ASM_X86_I8259_H */