;  ____________________________________________________________________
; 
;  Copyright (c) 2002, Andrew N. Sloss, Chris Wright and Dominic Symes
;  All rights reserved.
;  ____________________________________________________________________
; 
;  NON-COMMERCIAL USE License
;  
;  Redistribution and use in source and binary forms, with or without 
;  modification, are permitted provided that the following conditions 
;  are met: 
;  
;  1. For NON-COMMERCIAL USE only.
; 
;  2. Redistributions of source code must retain the above copyright 
;     notice, this list of conditions and the following disclaimer. 
; 
;  3. Redistributions in binary form must reproduce the above 
;     copyright notice, this list of conditions and the following 
;     disclaimer in the documentation and/or other materials provided 
;     with the distribution. 
; 
;  4. All advertising materials mentioning features or use of this 
;     software must display the following acknowledgement:
; 
;     This product includes software developed by Andrew N. Sloss,
;     Chris Wright and Dominic Symes. 
; 
;   THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS ``AS IS'' AND ANY 
;   EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
;   IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 
;   PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE CONTRIBUTORS BE 
;   LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 
;   OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 
;   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, 
;   OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 
;   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR 
;   TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 
;   OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
;   OF SUCH DAMAGE. 
; 
;  If you have questions about this license or would like a different
;  license please email :
; 
; 	andrew@sloss.net
; 
; 
; ****************************************************************************
; * Simple Little Operating System - SLOS
; ****************************************************************************

; ****************************************************************************
; *
; * Module      : handler.s
; * Description : handles the irq events
; * OS          : SLOS
; * Platform    : e7t
; * History     :
; *
; * 21 December 2001 Andrew N. Sloss
; * - started working on the handlers
; *   
; ****************************************************************************

; ****************************************************************************
; * EXPORT
; ****************************************************************************

     EXPORT     eventsIRQHandler

; ****************************************************************************
; * IMPORT
; ****************************************************************************

     IMPORT     eventTickService
     IMPORT     eventButtonService
     IMPORT     kernelScheduler

; ****************************************************************************
; * ROUTINES
; ****************************************************************************

     AREA IRQE7T,CODE,READONLY

; -- address of the IRQ controller for the Samsung KS32C50100. 

INTPND    DCD  0x03ff4004     ; IRQ controller 

; -- events_irq_handler -------------------------------------------------------
;
; Description  : handles the IRQ interrupt and determines the source and then
;                vectors to the correct interrupt rountine.
;

eventsIRQHandler

     SUB     r14, r14, #4
     STMFD   r13!, {r0-r3, r12, r14}    ; save context
	LDR     r0, INTPND	 
	LDR     r0, [r0]                   ; get IRQ source		
     TST     r0, #0x0400
     BNE     eventTickVeneer            ; if timer interrupt
     TST     r0, #0x0001		
     BNE     eventButtonVeneer          ; if button interrupt
     LDMFD   r13!, {r0-r3, r12, pc}^    ; unknown event ignore

eventButtonVeneer

     BL      eventButtonService
     LDMFD   r13!, {r0-r3, r12, pc}^    ; return to task

eventTickVeneer

     BL      eventTickService
     B       kernelScheduler
	END