linux/arch/powerpc/sysdev/dcr-low.S
Benjamin Herrenschmidt 6d2170be45 powerpc/4xx: Extended DCR support v2
This adds supports to the "extended" DCR addressing via the indirect
mfdcrx/mtdcrx instructions supported by some 4xx cores (440H6 and
later).

I enabled the feature for now only on AMCC 460 chips.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-12-21 14:21:15 +11:00

46 lines
983 B
ArmAsm

/*
* "Indirect" DCR access
*
* Copyright (c) 2004 Eugene Surovegin <ebs@ebshome.net>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*/
#include <asm/ppc_asm.h>
#include <asm/processor.h>
#include <asm/bug.h>
#define DCR_ACCESS_PROLOG(table) \
cmpli cr0,r3,1024; \
rlwinm r3,r3,4,18,27; \
lis r5,table@h; \
ori r5,r5,table@l; \
add r3,r3,r5; \
bge- 1f; \
mtctr r3; \
bctr; \
1: trap; \
EMIT_BUG_ENTRY 1b,__FILE__,__LINE__,0; \
blr
_GLOBAL(__mfdcr)
DCR_ACCESS_PROLOG(__mfdcr_table)
_GLOBAL(__mtdcr)
DCR_ACCESS_PROLOG(__mtdcr_table)
__mfdcr_table:
mfdcr r3,0; blr
__mtdcr_table:
mtdcr 0,r4; blr
dcr = 1
.rept 1023
mfdcr r3,dcr; blr
mtdcr dcr,r4; blr
dcr = dcr + 1
.endr