xref: /linux/arch/powerpc/sysdev/dcr-low.S (revision 6f52b16c5b29b89d92c0e7236f4655dc8491ad70)
1/*
2 * "Indirect" DCR access
3 *
4 * Copyright (c) 2004 Eugene Surovegin <ebs@ebshome.net>
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under  the terms of  the GNU General Public License as published by the
8 * Free Software Foundation;  either version 2 of the License, or (at your
9 * option) any later version.
10 */
11
12#include <asm/ppc_asm.h>
13#include <asm/processor.h>
14#include <asm/bug.h>
15#include <asm/export.h>
16
17#define DCR_ACCESS_PROLOG(table) \
18	cmpli	cr0,r3,1024;	 \
19	rlwinm  r3,r3,4,18,27;   \
20	lis     r5,table@h;      \
21	ori     r5,r5,table@l;   \
22	add     r3,r3,r5;        \
23	bge-	1f;		 \
24	mtctr   r3;              \
25	bctr;			 \
261:	trap;			 \
27	EMIT_BUG_ENTRY 1b,__FILE__,__LINE__,0;	\
28	blr
29
30_GLOBAL(__mfdcr)
31	DCR_ACCESS_PROLOG(__mfdcr_table)
32EXPORT_SYMBOL(__mfdcr)
33
34_GLOBAL(__mtdcr)
35	DCR_ACCESS_PROLOG(__mtdcr_table)
36EXPORT_SYMBOL(__mtdcr)
37
38__mfdcr_table:
39	mfdcr  r3,0; blr
40__mtdcr_table:
41	mtdcr  0,r4; blr
42
43dcr     = 1
44        .rept   1023
45	mfdcr   r3,dcr; blr
46	mtdcr   dcr,r4; blr
47	dcr     = dcr + 1
48	.endr
49