irq_asm.h

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/* irq_asm.h
 *
 *  This include file has defines to represent some contant used
 *  to program and manage the  Intel 8259 interrupt controller
 *
 *
 *  COPYRIGHT (c) 1998 valette@crf.canon.fr
 *
 *  Copyright (c) 2016 Chris Johns <chrisj@rtems.org>
 *
 *  The license and distribution terms for this file may be
 *  found in the file LICENSE in this distribution or at
 *  http://www.rtems.org/license/LICENSE.
 */
#ifndef __I8259S_H__
#define __I8259S_H__

#define BSP_ASM_IRQ_VECTOR_BASE 0x20

#define PIC_MASTER_COMMAND_IO_PORT      0x20    
#define PIC_SLAVE_COMMAND_IO_PORT       0xa0    
#define PIC_MASTER_IMR_IO_PORT          0x21    
#define PIC_SLAVE_IMR_IO_PORT           0xa1    


#define PIC_EOSI    0x60    
#define PIC_EOI     0x20    

/* Operation control word type 3.  Bit 3 (0x08) must be set. Even address. */
#define PIC_OCW3_RIS        0x01            /* 1 = read IS, 0 = read IR */
#define PIC_OCW3_RR         0x02            /* register read */
#define PIC_OCW3_P          0x04            /* poll mode command */
/* 0x08 must be 1 to select OCW3 vs OCW2 */
#define PIC_OCW3_SEL        0x08            /* must be 1 */
/* 0x10 must be 0 to select OCW3 vs ICW1 */
#define PIC_OCW3_SMM        0x20            /* special mode mask */
#define PIC_OCW3_ESMM       0x40            /* enable SMM */

#endif