int-handler.s

一个2.4.21版本的嵌入式linux内核

/*
 * FILE NAME
 *	arch/mips/vr41xx/common/int-handler.S
 *
 * BRIEF MODULE DESCRIPTION
 *	Interrupt dispatcher for the NEC VR4100 series.
 *
 * Author: Yoichi Yuasa
 *         [e-mail] or [e-mail]
 *
 * Copyright 2001 MontaVista Software Inc.
 *
 *  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 SOFTWARE IS PROVIDED ``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 AUTHOR 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.
 *
 *  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.,
 *  675 Mass Ave, Cambridge, MA 02139, USA.
 */
/*
 * Changes:
 *  MontaVista Software Inc. <[e-mail]> or <[e-mail]>
 *  - New creation, NEC VR4100 series are supported.
 */
#include <asm/asm.h>
#include <asm/regdef.h>
#include <asm/mipsregs.h>
#include <asm/stackframe.h>

		.text
		.set	noreorder

		.align	5
		NESTED(vr41xx_handle_interrupt, PT_SIZE, ra)
		.set	noat
		SAVE_ALL
		CLI
		.set	at
		.set	noreorder

		/*
		 * Get the pending interrupts
		 */
		mfc0	t0, CP0_CAUSE
		mfc0	t1, CP0_STATUS
		andi	t0, 0xff00
		and	t0, t0, t1

		andi	t1, t0, CAUSEF_IP7	# timer interrupt
		beqz	t1, 1f
		li	a0, 7
		jal	ll_timer_interrupt
		move	a1, sp
		j	ret_from_irq

1:
		andi	t1, t0, 0x7800		# check for IP3-6
		beqz	t1, 2f

		andi	t1, t0, CAUSEF_IP3	# check for IP3
		bnez	t1, handle_it
		li	a0, 3

		andi	t1, t0, CAUSEF_IP4	# check for IP4
		bnez	t1, handle_it
		li	a0, 4

		andi	t1, t0, CAUSEF_IP5	# check for IP5
		bnez	t1, handle_it
		li	a0, 5

		andi	t1, t0, CAUSEF_IP6	# check for IP6
		bnez	t1, handle_it
		li	a0, 6

2:
		andi	t1, t0, CAUSEF_IP2	# check for IP2
		beqz	t1, 3f
		move	a0, sp
		jal	icu_irqdispatch
		nop
		j	ret_from_irq
		nop

3:
		andi	t1, t0, CAUSEF_IP0	# check for IP0
		bnez	t1, handle_it
		li	a0, 0

		andi	t1, t0, CAUSEF_IP1	# check for IP1
		bnez	t1, handle_it
		li	a0, 1

		j	spurious_interrupt
		nop

handle_it:
		jal	do_IRQ
		move	a1, sp
		j	ret_from_irq
		END(vr41xx_handle_interrupt)