/* Copyright (C) 2004  David Decotigny
 
    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License
    as published by the Free Software Foundation; either version 2
    of the License, or (at your option) any later version.
    
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.
    
    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
    USA. 
 */
 #ifndef _SOS_HWINTR_H_
 #define _SOS_HWINTR_H_
 
 
 /**
  * @file irq.c
  *
  * Hardware interrupts routines management.
  */
 
 
 #include <sos/errno.h>
 #include "cpu_context.h"
 
 
 #define sos_save_flags(flags) \
   asm volatile("pushfl ; popl %0":"=g"(flags)::"memory")
 #define sos_restore_flags(flags) \
   asm volatile("push %0; popfl"::"g"(flags):"memory")
 
 
 #define sos_disable_IRQs(flags)    \
   ({ sos_save_flags(flags); asm("cli\n"); })
 #define sos_restore_IRQs(flags)    \
   sos_restore_flags(flags)
 
 
 /* Usual IRQ levels */
 #define SOS_IRQ_TIMER         0
 #define SOS_IRQ_KEYBOARD      1
 #define SOS_IRQ_SLAVE_PIC     2
 #define SOS_IRQ_COM2          3
 #define SOS_IRQ_COM1          4
 #define SOS_IRQ_LPT2          5
 #define SOS_IRQ_FLOPPY        6
 #define SOS_IRQ_LPT1          7
 #define SOS_IRQ_8_NOT_DEFINED 8
 #define SOS_IRQ_RESERVED_1    9
 #define SOS_IRQ_RESERVED_2    10
 #define SOS_IRQ_RESERVED_3    11
 #define SOS_IRQ_RESERVED_4    12
 #define SOS_IRQ_COPROCESSOR   13
 #define SOS_IRQ_HARDDISK      14
 #define SOS_IRQ_RESERVED_5    15
 
 
 /** Definition of an hardware IRQ handler */
 typedef void (*sos_irq_handler_t)(int irq_level);
 
 
 /** Setup the PIC */
 sos_ret_t sos_irq_subsystem_setup(void);
 
 
 /**
  * If the routine is not NULL, the IDT is setup to call an IRQ
  * wrapper upon interrupt, which in turn will call the routine, and
  * the PIC is programmed to raise an irq.\ If the routine is
  * NULL, we disable the irq line.
  */
 sos_ret_t sos_irq_set_routine(int irq_level,
                               sos_irq_handler_t routine);
 
 sos_irq_handler_t sos_irq_get_routine(int irq_level);
 
 
 /**
  * Tell how many nested IRQ handler have been fired
  */
 sos_ui32_t sos_irq_get_nested_level(void);
 
 
 /**
  * Return TRUE when we are currently executing in interrupt context
  */
 #define sos_servicing_irq() \
   (sos_irq_get_nested_level() > 0)
 
 
 #endif /* _SOS_HWINTR_H_ */