NetBSD/sys/arch/atari/dev/hdfd_intr.s

150 lines
4.7 KiB
ArmAsm

/* $NetBSD: hdfd_intr.s,v 1.4 1997/01/01 21:12:57 leo Exp $
/*
* Copyright (c) 1996 Leo Weppelman.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Leo Weppelman.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND 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 REGENTS OR 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.
*
*/
#include "assym.h"
#define ASSEMBLER /* XXX */
#include <atari/dev/hdfdreg.h>
.text
.globl _fddmaaddr
.globl _fdio_addr,_fddmalen
.globl _mfp_hdfd_nf, _mfp_hdfd_fifo
/*
* Entry point when there is no fifo. Handles the read/write
* interrupts a bit faster because it *knows* that there is only
* one character waiting.
*/
_mfp_hdfd_nf:
addql #1,nintr | add another interrupt
moveml d0-d1/a0-a1,sp@- | Save scratch registers
movl _fdio_addr,a0 | Get base of fdc registers
movb a0@(fdsts),d0 | Get fdsts
btst #5,d0 | Dma active?
jeq hdfdc_norm | No, normal interrupt
tstl _fddmalen | Bytecount zero?
jeq hdfdc_norm | Yes -> normal interrupt
movl _fddmaaddr, a1 | a1 = dmabuffer
btst #6,d0 | Read?
jeq hdfd_wrt_nf | No, write
hdfd_rd_nf:
movb a0@(fddata),a1@+ | Get a byte
1:
subql #1, _fddmalen | decrement bytecount
movl a1,_fddmaaddr | update dma pointer
| addql #1,_cnt+V_INTR | chalk up another interrupt
moveml sp@+,d0-d1/a0-a1
rte
hdfd_wrt_nf:
movb a1@+,a0@(fddata) | Push a byte
jra 1b | And get out...
/*
* Systems *with* fifo's enter here.
*/
_mfp_hdfd_fifo:
addql #1,_intrcnt_user+88 | add another interrupt
moveml d0-d1/a0-a1,sp@- | Save scratch registers
movl _fdio_addr,a0 | Get base of fdc registers
movb a0@(fdsts),d0 | Get fdsts
btst #5,d0 | Dma active?
jeq hdfdc_norm | No, normal interrupt
movl _fddmaaddr, a1 | a1 = dmabuffer
btst #6,d0 | Read?
jeq hdfd_wrt | No, write
hdfd_rd:
tstl _fddmalen | Bytecount zero?
jeq hdfdc1 | Yes -> done
movb a0@(fddata),a1@+ | Get a byte
subql #1, _fddmalen | decrement bytecount
movb a0@(fdsts),d0 | Get fdsts
andb #0xa0,d0 | both NE7_NDM and NE7_RQM active?
cmpb #0xa0,d0
jne hdfdc1 | No, end of this batch
jra hdfd_rd
hdfd_wrt:
tstl _fddmalen | Bytecount zero?
jeq hdfdc1 | Yes -> done
movb a1@+,a0@(fddata) | Push a byte
subql #1, _fddmalen | decrement bytecount
jra hdfdc1
movb a0@(fdsts),d0 | Get fdsts
andb #0xa0,d0 | both NE7_NDM and NE7_RQM active?
cmpb #0xa0,d0
jne hdfdc1 | No, end of this batch
jra hdfd_wrt
hdfdc1:
movl a1,_fddmaaddr | update buffer pointer
btst #5,d0 | Dma still active?
jeq hdfdc_norm | No -> take normal interrupt
/*
* Exit for read/write interrupts. Calling 'rei' this often
* seems wrong....
*/
hdfdc_xit:
addql #1,_cnt+V_INTR | chalk up another interrupt
moveml sp@+,d0-d1/a0-a1
rte
/*
* No (more) data transfer interrupts. Do the normal
* stuff.
*/
hdfdc_norm:
tstl nintr
jeq 0f
movl nintr,d0
clrl nintr
addl d0, _intrcnt_user+88 | add another interrupt
addl d0, _cnt+V_INTR | chalk up another interrupt
0: jbsr _fdc_ctrl_intr | handle interrupt
moveml sp@+,d0-d1/a0-a1 | and saved registers
jra rei
.data
nintr:
.long 0