/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * "Indirect" DCR access
 *
 * Copyright (c) 2004 Eugene Surovegin <ebs@ebshome.net>
 */

#include <linux/export.h>
#include <asm/ppc_asm.h>
#include <asm/processor.h>
#include <asm/bug.h>

#define DCR_ACCESS_PROLOG(table) \
        cmplwi  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)
EXPORT_SYMBOL(__mfdcr)

_GLOBAL(__mtdcr)
        DCR_ACCESS_PROLOG(__mtdcr_table)
EXPORT_SYMBOL(__mtdcr)

__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