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/*
* linux/arch/mips/philips/nino/int-handler.S
*
* Copyright (C) 1999 Harald Koerfgen
* Copyright (C) 2000 Jim Pick (jim@jimpick.com)
* Copyright (C) 2001 Steven J. Hill (sjhill@realitydiluted.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Interrupt handler for Philips Nino.
*/
#include <asm/asm.h>
#include <asm/regdef.h>
#include <asm/mipsregs.h>
#include <asm/stackframe.h>
#include <asm/tx3912.h>
.data
.globl HighPriVect
HighPriVect: .word spurious # Reserved
.word io_posnegint0 # IOPOSINT(0) or IONEGINT(0)
.word spurious # CHIDMACNTINT
.word spurious # TELDMACNTINT
.word spurious # SNDDMACNTINT
.word spurious # Reserved
.word io_negint56 # IONEGINT(6) or IONEGINT(5)
.word spurious # Reserved
.word io_posint56 # IOPOSINT(6) or IOPOSINT(5)
.word spurious # Reserved
.word spurious # UARTBRXINT
.word uarta_rx # UARTARXINT
.word spurious # Reserved
.word periodic_timer # PERINT
.word spurious # ALARMINT
.word spurious # POSPWROKINT or NEGPWROKINT
/*
* Here is the entry point to handle all interrupts.
*/
.text
.set noreorder
.align 5
NESTED(nino_handle_int, PT_SIZE, ra)
.set noat
SAVE_ALL
CLI
.set at
/*
* Get pending Interrupts
*/
mfc0 t0, CP0_CAUSE # Get pending interrupts
andi t2, t0, IE_IRQ4 # IRQ4 (high priority)
bne t2, IE_IRQ4, low_priority
nop
/*
* Ok, we've got a high priority interrupt (a.k.a. an external interrupt).
* Read Interrupt Status Register 6 to get vector.
*/
high_priority:
lui t0, %hi(IntStatus6)
lw t1, %lo(IntStatus6)(t0)
andi t1, INT6_INTVECT
la t2, HighPriVect
addu t1, t1, t2
lw t2, 0(t1)
jr t2
nop
/*
* Ok, we've got one of over a hundred other interupts.
*/
low_priority:
lui t0, %hi(IntStatus1)
lw t1, %lo(IntStatus1)(t0)
j handle_it
li a0, 20
/*
* We don't currently handle spurious interrupts.
*/
spurious:
j spurious_interrupt
nop
/*
* We have the IRQ number, dispatch to the real handler.
*/
handle_it: jal do_IRQ
move a1,sp
j ret_from_irq
nop
/************************************
* High priority interrupt mappings *
************************************/
/*
* Periodic timer - IRQ 0
*/
periodic_timer:
j handle_it
li a0, 0
/*
* UARTA RX - IRQ 3
*/
uarta_rx:
j handle_it
li a0, 3
/*
* GPIO Pin 0 transition - IRQ 10
*/
io_posnegint0:
j handle_it
li a0, 10
/*
* GPIO Pin 5 or 6 transition (0-to-1) - IRQ 11
*/
io_posint56:
j handle_it
li a0, 11
/*
* GPIO Pin 5 or 6 transition (1-to-0) - IRQ 12
*/
io_negint56:
j handle_it
li a0, 12
END(nino_handle_int)
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