NetBSD-5.0.2/sys/arch/pmax/pmax/locore_machdep.S
/* $NetBSD: locore_machdep.S,v 1.23 2005/12/11 12:18:39 christos Exp $ */
/*
* Copyright (c) 1992, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Digital Equipment Corporation and Ralph Campbell.
*
* 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. 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.
*
* Copyright (C) 1989 Digital Equipment Corporation.
* Permission to use, copy, modify, and distribute this software and
* its documentation for any purpose and without fee is hereby granted,
* provided that the above copyright notice appears in all copies.
* Digital Equipment Corporation makes no representations about the
* suitability of this software for any purpose. It is provided "as is"
* without express or implied warranty.
*
* from: Header: /sprite/src/kernel/mach/ds3100.md/RCS/loMem.s,
* v 1.1 89/07/11 17:55:04 nelson Exp SPRITE (DECWRL)
* from: Header: /sprite/src/kernel/mach/ds3100.md/RCS/machAsm.s,
* v 9.2 90/01/29 18:00:39 shirriff Exp SPRITE (DECWRL)
* from: Header: /sprite/src/kernel/vm/ds3100.md/vmPmaxAsm.s,
* v 1.1 89/07/10 14:27:41 nelson Exp SPRITE (DECWRL)
*
* @(#)locore.s 8.5 (Berkeley) 1/4/94
*/
/*
* DECstation-specific mips locore code.
*/
#include <mips/asm.h>
#include <mips/cpuregs.h> /* XXX - misnomer? */
#include "sii.h"
#include "opt_dec_5100.h"
#include "opt_dec_5400.h"
.set noreorder
#if NSII > 0
/*
* Copy data to a DMA buffer padded with 16 bits of data, 16
* bits of padding per 32bit word (e.g., for pmin/pmax sii DMA).
*
* The DMA bufffer can only be written one short at a time
* (and takes ~14 cycles).
*
* CopyToBuffer(src, dst, length)
* u_short *src; NOTE: must be short aligned
* u_short *dst;
* int length;
*/
LEAF(CopyToBuffer)
blez a2, 2f
nop
1:
lhu t0, 0(a0) # read 2 bytes of data
subu a2, a2, 2
addu a0, a0, 2
addu a1, a1, 4
bgtz a2, 1b
sh t0, -4(a1) # write 2 bytes of data to buffer
2:
j ra
nop
END(CopyToBuffer)
/*
* Copy data from the DMA buffer.
* The DMA bufffer can only be read one short at a time
* (and takes ~12 cycles).
*
* CopyFromBuffer(src, dst, length)
* u_short *src;
* char *dst;
* int length;
*/
LEAF(CopyFromBuffer)
and t0, a1, 1 # test for aligned dst
beq t0, zero, 3f
nop
blt a2, 2, 7f # at least 2 bytes to copy?
nop
1:
lhu t0, 0(a0) # read 2 bytes of data from buffer
addu a0, a0, 4 # keep buffer pointer word aligned
addu a1, a1, 2
subu a2, a2, 2
sb t0, -2(a1)
srl t0, t0, 8
bge a2, 2, 1b
sb t0, -1(a1)
3:
blt a2, 2, 7f # at least 2 bytes to copy?
nop
6:
lhu t0, 0(a0) # read 2 bytes of data from buffer
addu a0, a0, 4 # keep buffer pointer word aligned
addu a1, a1, 2
subu a2, a2, 2
bge a2, 2, 6b
sh t0, -2(a1)
7:
ble a2, zero, 9f # done?
nop
lhu t0, 0(a0) # copy one more byte
nop
sb t0, 0(a1)
9:
j ra
nop
END(CopyFromBuffer)
#endif /* NSII > 0 */
/*
* Write-buffer flush for writebuffer hardware on DEC mips r2000a
*/
#if defined(DEC_5100) || defined(DEC_5400)
LEAF(dec_mips1_wbflush)
ALEAF(kn230_wbflush)
ALEAF(kn210_wbflush)
mfc0 v0, MIPS_COP_0_STATUS # save original SR in v0
li t0, 0x80000000 # set CU3 bit
or v1, v0 ,t0 # v1 = v0 | 0x80000000
nop
mtc0 v1, MIPS_COP_0_STATUS
nop /* two more cycles to complete */
nop
1: # spin
bc3f 1b # until write buffer drained
nop # (branch delay slot)
mtc0 v0, MIPS_COP_0_STATUS # restore SR on exit
nop
j ra
nop
END(dec_mips1_wbflush)
#endif /* defined(DEC_5100) || defined(DEC_5400) */