NetBSD/sys/arch/arm32/vidc/lmc1982.S

144 lines
3.7 KiB
ArmAsm

/* $NetBSD: lmc1982.S,v 1.2 1997/10/14 12:03:14 mark Exp $ */
/*
* Copyright (c) 1996, Danny C Tsen.
* Copyright (c) 1996, VLSI Technology Inc. All Rights Reserved.
*
* 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 Michael L. Hitch.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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.
*
* NS LMC1982, Stereo and volume control.
*/
#include <machine/asm.h>
#include <arm32/iomd/iomdreg.h>
#include <arm32/mainbus/lmc1982.h>
/*
* r0=address
* r1=value
* r2 control IOCR
* r3=control FREQCON
* r4 timeout
* r5 FREQimage
* r6 FREQCON
* r7 IOCBase (IOCR address)
* r4, r8 scratch
*/
ENTRY(volume_ctl)
stmfd sp!, {r0-r8, lr}
/*
* operate the volume control circuit
*/
mov r7, #(IOMD_BASE)
add r6, r7, #(FREQCON << 2) /* location of FREQCON register */
ldr r5, Lvfreqcon /* frequency reg shadow */
orr r0,r0,#0x40 /* chip address adder */
ldrb r2,[r7] /* get IOCR value */
orr r2,r2,#IOCR_AUDIO /*insure data is high*/
strb r2,[r7]
mov r4,#8
ldrb r3,[r5] /* get freqcon */
orr r3,r3,#(LID | LCLOCK) /* ID and CLOCK high */
strb r3,[r6]
mov r4,#10
bl _waitabit /* wait 10 usec */
bic r3,r3,#(LID)
strb r3,[r6] /* lower ID bit */
bl _shift
orr r3,r3,#(LID | LCLOCK) /* ID and CLOCK high */
strb r3,[r6]
mov r0,r1
bl _shift
mov r4,#10
bl _waitabit /* wait 10 usec */
bic r3,r3,#(LID)
strb r3,[r6] /* lower ID bit */
mov r4,#1
bl _waitabit /* wait 1 usec */
orr r3,r3,#(LID | LCLOCK) /* ID and CLOCK high */
strb r3,[r6]
ldmfd sp!, {r0-r8, pc}
Lvfreqcon:
.word _vfreqcon
_shift: /* data in r0 */
mov r4,#8 /* number of bits in address */
sloop:
bic r3,r3,#(LCLOCK)
strb r3,[r6] /* lower CLOCK bit */
movs r0,r0,LSR #1 /* get bit */
orrcs r2,r2,#IOCR_AUDIO /* insure data is high */
biccc r2,r2,#IOCR_AUDIO /* insure data is low */
strb r2,[r7]
orr r3,r3,#(LCLOCK)
strb r3,[r6] /* raise CLOCK bit */
subs r4,r4,#1
bne sloop
mov pc,lr
_waitabit:
mov r8,#15
wloop:
subs r8,r8,#1
bne wloop
subs r4,r4,#1
bne _waitabit
mov pc,lr
/*
* r0: addr
* r1: counter
*/
ENTRY(conv_jap)
stmfd sp!, {r2-r4, lr}
movs r2, r1 /* counter */
beq conv_jap_end
cloop:
ldrb r3, [r0]
eor r3, r3, #0x80
strb r3, [r0], #1
subs r2, r2, #1
bne cloop
conv_jap_end:
ldmfd sp!, {r2-r4, pc}