NetBSD-5.0.2/sys/arch/powerpc/ibm4xx/trap_subr.S
/* $NetBSD: trap_subr.S,v 1.11 2007/10/17 19:56:39 garbled Exp $ */
/*
* Copyright 2001 Wasabi Systems, Inc.
* All rights reserved.
*
* Written by Eduardo Horvath and Simon Burge for Wasabi Systems, Inc.
*
* 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 for the NetBSD Project by
* Wasabi Systems, Inc.
* 4. The name of Wasabi Systems, Inc. may not be used to endorse
* or promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``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 WASABI SYSTEMS, INC
* 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) 1995, 1996 Wolfgang Solfrank.
* Copyright (C) 1995, 1996 TooLs GmbH.
* 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 TooLs GmbH.
* 4. The name of TooLs GmbH may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``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 TOOLS GMBH 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.
*/
/*
* NOTICE: This is not a standalone file. to use it, #include it in
* your port's locore.S, like so:
*
* #include <powerpc/ibm4xx/trap_subr.S>
*/
/*
* Data used during primary/secondary traps/interrupts
*/
#define tempsave 0x2e0 /* primary save area for trap handling */
#define disisave 0x3e0 /* primary save area for dsi/isi traps */
#define exitsave 0x4e0 /* use this so trap return does not conflict */
/*
* XXX Interrupt and spill stacks need to be per-CPU.
*/
#define GET_PCB(rX) \
GET_CPUINFO(rX); \
lwz rX,CI_CURPCB(rX)
#define STANDARD_PROLOG(savearea) \
mtsprg 1,1; /* save SP */ \
stmw 28,savearea(0); /* free r28-r31 */ \
mflr 28; /* save LR */ \
mfcr 29; /* save CR */ \
mfsrr1 31; /* Test whether we already had PR set */ \
mtcr 31; \
bc 4,17,1f; /* branch if PSL_PR is clear */ \
GET_PCB(1); \
addi 1,1,USPACE; /* stack is top of user struct */ \
1:
#define CRITICAL_PROLOG(savearea) \
mtsprg 1,1; /* save SP */ \
stmw 28,savearea(0); /* free r28-r31 */ \
mflr 28; /* save LR */ \
mfcr 29; /* save CR */ \
mfsrr2 30; /* Fake a standard trap */ \
mtsrr0 30; \
mfsrr3 31; /* Test whether we already had PR set */ \
mtsrr1 31; \
mtcr 31; \
bc 4,17,1f; /* branch if PSL_PR is clear */ \
GET_PCB(1); \
addi 1,1,USPACE; /* stack is top of user struct */ \
1:
/* Standard handler saves r1,r28-31,LR,CR, sets up the stack and calls s_trap */
#define STANDARD_EXC_HANDLER(name)\
.globl _C_LABEL(name ## trap),_C_LABEL(name ## size) ; \
_C_LABEL(name ## trap): \
STANDARD_PROLOG(tempsave); \
bla s_trap ; \
_C_LABEL(name ## size) = .-_C_LABEL(name ## trap)
/* Access exceptions also need DEAR and ESR saved */
#define ACCESS_EXC_HANDLER(name)\
.globl _C_LABEL(name ## trap),_C_LABEL(name ## size) ; \
_C_LABEL(name ## trap): \
STANDARD_PROLOG(tempsave); \
mfdear 30; \
mfesr 31; \
stmw 30,16+tempsave(0); \
bla s_trap ; \
_C_LABEL(name ## size) = .-_C_LABEL(name ## trap)
/* Maybe this should call ddb.... */
#define CRITICAL_EXC_HANDLER(name)\
.globl _C_LABEL(name ## trap),_C_LABEL(name ## size) ; \
_C_LABEL(name ## trap): \
CRITICAL_PROLOG(tempsave); \
bla s_trap ; \
_C_LABEL(name ## size) = .-_C_LABEL(name ## trap)
/*
* This code gets copied to all the trap vectors
* (except ISI/DSI, ALI, the interrupts, and possibly the debugging
* traps when using IPKDB).
*/
.text
STANDARD_EXC_HANDLER(default)
ACCESS_EXC_HANDLER(ali)
ACCESS_EXC_HANDLER(dsi)
ACCESS_EXC_HANDLER(isi)
STANDARD_EXC_HANDLER(debug)
CRITICAL_EXC_HANDLER(mchk)
/*
* This one for the external interrupt handler.
*/
.globl _C_LABEL(extint),_C_LABEL(extsize)
_C_LABEL(extint):
mtsprg 1,1 /* save SP */
stmw 28,tempsave(0) /* free r28-r31 */
mflr 28 /* save LR */
mfcr 29 /* save CR */
mfxer 30 /* save XER */
GET_CPUINFO(1)
lwz 31,CI_INTRDEPTH(1) /* were we already running on intstk? */
addic. 31,31,1
stw 31,CI_INTRDEPTH(1)
lwz 1,CI_INTSTK(1) /* get intstk */
beq 1f
mfsprg 1,1 /* yes, get old SP */
1:
ba extintr
_C_LABEL(extsize) = .-_C_LABEL(extint)
#if defined(DDB) || defined(KGDB)
#define ddbsave 0xde0 /* primary save area for DDB */
/*
* In case of DDB we want a separate trap catcher for it
*/
.local ddbstk
.comm ddbstk,INTSTK,8 /* ddb stack */
.globl _C_LABEL(ddblow),_C_LABEL(ddbsize)
_C_LABEL(ddblow):
mtsprg 1,1 /* save SP */
stmw 28,ddbsave(0) /* free r28-r31 */
mflr 28 /* save LR */
mfcr 29 /* save CR */
lis 1,ddbstk+INTSTK@ha /* get new SP */
addi 1,1,ddbstk+INTSTK@l
bla ddbtrap
_C_LABEL(ddbsize) = .-_C_LABEL(ddblow)
#endif /* DDB || KGDB */
#ifdef IPKDB
#define ipkdbsave 0xde0 /* primary save area for IPKDB */
/*
* In case of IPKDB we want a separate trap catcher for it
*/
.local ipkdbstk
.comm ipkdbstk,INTSTK,8 /* ipkdb stack */
.globl _C_LABEL(ipkdblow),_C_LABEL(ipkdbsize)
_C_LABEL(ipkdblow):
mtsprg 1,1 /* save SP */
stmw 28,ipkdbsave(0) /* free r28-r31 */
mflr 28 /* save LR */
mfcr 29 /* save CR */
lis 1,ipkdbstk+INTSTK@ha /* get new SP */
addi 1,1,ipkdbstk+INTSTK@l
bla ipkdbtrap
_C_LABEL(ipkdbsize) = .-_C_LABEL(ipkdblow)
#endif /* IPKDB */
#ifdef DEBUG
#define TRAP_IF_ZERO(r) tweqi r,0
#else
#define TRAP_IF_ZERO(r)
#endif
/*
* FRAME_SETUP assumes:
* SPRG1 SP (1)
* savearea r28-r31,DEAR,ESR (DEAR & ESR only for DSI traps)
* 28 LR
* 29 CR
* 1 kernel stack
* LR trap type
* SRR0/1 as at start of trap
*/
#define FRAME_SETUP(savearea) \
/* Have to enable translation to allow access of kernel stack: */ \
mfsrr0 30; \
mfsrr1 31; \
stmw 30,savearea+24(0); \
mfpid 30; \
li 31,KERNEL_PID; \
mtpid 31; \
mfmsr 31; \
ori 31,31,(PSL_DR|PSL_IR)@l; \
mtmsr 31; \
isync; \
mfsprg 31,1; \
stwu 31,-FRAMELEN(1); \
stw 30,FRAME_PID+8(1); \
stw 0,FRAME_0+8(1); \
stw 31,FRAME_1+8(1); \
stw 28,FRAME_LR+8(1); \
stw 29,FRAME_CR+8(1); \
lmw 28,savearea(0); \
stmw 2,FRAME_2+8(1); \
lmw 28,savearea+16(0); \
mfxer 3; \
mfctr 4; \
mflr 5; \
andi. 5,5,0xff00; \
stw 3,FRAME_XER+8(1); \
stw 4,FRAME_CTR+8(1); \
stw 5,FRAME_EXC+8(1); \
stw 28,FRAME_DEAR+8(1); \
stw 29,FRAME_ESR+8(1); \
stw 30,FRAME_SRR0+8(1); \
stw 31,FRAME_SRR1+8(1)
#define FRAME_LEAVE(savearea) \
/* Now restore regs: */ \
lwz 3,FRAME_PID+8(1); \
lwz 4,FRAME_SRR1+8(1); \
bl _C_LABEL(ctx_setup); \
TRAP_IF_ZERO(3); \
stw 3,FRAME_PID+8(1); \
lmw 26,FRAME_LR+8(1); \
mtlr 26; \
mtcr 27; \
mtxer 28; \
mtctr 29; \
mtsrr0 30; \
mtsrr1 31; \
lmw 2,FRAME_2+8(1); \
lwz 0,FRAME_0+8(1); \
stmw 29,savearea(0); \
lwz 30,FRAME_PID+8(1); \
lwz 1,FRAME_1+8(1); \
mfmsr 31; \
li 29,(PSL_DR|PSL_IR)@l; \
andc 31,31,29; \
mfcr 29; \
mtcr 29; \
mtmsr 31; \
isync; \
TRAP_IF_ZERO(30); \
mtpid 30; \
lmw 29,savearea(0)
realtrap: /* entry point after IPKDB is done with exception */
/* Test whether we already had PR set */
mfsrr1 1
mtcr 1
mfsprg 1,1 /* restore SP (might have been
overwritten) */
bc 4,17,s_trap /* branch if PSL_PR is false */
GET_PCB(1)
addi 1,1,USPACE /* stack is top of user struct */
/*
* Now the common trap catching code.
*/
s_trap:
FRAME_SETUP(tempsave)
/* Now we can recover interrupts again: */
trapagain:
wrteei 1 /* Enable interrupts */
/* Call C trap code: */
addi 3,1,8
bl _C_LABEL(trap)
.globl _C_LABEL(trapexit)
_C_LABEL(trapexit):
/* Disable interrupts: */
wrteei 0
/* Test AST pending: */
lwz 5,FRAME_SRR1+8(1)
mtcr 5
bc 4,17,1f /* branch if PSL_PR is false */
GET_CPUINFO(3)
lwz 4,CI_ASTPENDING(3)
andi. 4,4,1
beq 1f
li 6,EXC_AST
stw 6,FRAME_EXC+8(1)
b trapagain
1:
FRAME_LEAVE(exitsave)
rfi
ba . /* Protect against prefetch */
.globl _C_LABEL(sctrap),_C_LABEL(scsize),_C_LABEL(sctrapexit)
_C_LABEL(sctrap):
STANDARD_PROLOG(tempsave);
bla s_sctrap
_C_LABEL(scsize) = .-_C_LABEL(sctrap)
s_sctrap:
FRAME_SETUP(tempsave)
/* Now we can recover interrupts again: */
wrteei 1 /* Enable interrupts */
/* Call the appropriate syscall handler: */
addi 3,1,8
GET_CPUINFO(4)
lwz 4,CI_CURLWP(4)
lwz 4,L_PROC(4)
lwz 4,P_MD_SYSCALL(4)
mtctr 4
bctrl
_C_LABEL(sctrapexit):
/* Disable interrupts: */
wrteei 0
/* Test AST pending: */
lwz 5,FRAME_SRR1+8(1)
mtcr 5
bc 4,17,1f /* branch if PSL_PR is false */
GET_CPUINFO(3)
lwz 4,CI_ASTPENDING(3)
andi. 4,4,1
beq 1f
li 6,EXC_AST
stw 6,FRAME_EXC+8(1)
b trapagain
1:
FRAME_LEAVE(exitsave)
rfi
ba . /* Protect against prefetch */
/*
* External interrupt second level handler
*/
#define INTRENTER \
/* Save non-volatile registers: */ \
stwu 1,-IFRAMELEN(1); /* temporarily */ \
stw 0,IFRAME_R0(1); \
mfsprg 0,1; /* get original SP */ \
stw 0,IFRAME_R1(1); /* and store it */ \
stw 3,IFRAME_R3(1); \
stw 4,IFRAME_R4(1); \
stw 5,IFRAME_R5(1); \
stw 6,IFRAME_R6(1); \
stw 7,IFRAME_R7(1); \
stw 8,IFRAME_R8(1); \
stw 9,IFRAME_R9(1); \
stw 10,IFRAME_R10(1); \
stw 11,IFRAME_R11(1); \
stw 12,IFRAME_R12(1); \
stw 28,IFRAME_LR(1); /* saved LR */ \
stw 29,IFRAME_CR(1); /* saved CR */ \
stw 30,IFRAME_XER(1); /* saved XER */ \
lmw 28,tempsave(0); /* restore r28-r31 */ \
mfctr 6; \
GET_CPUINFO(5); \
lwz 5,CI_INTRDEPTH(5); \
mfsrr0 4; \
mfsrr1 3; \
stw 6,IFRAME_CTR(1); \
stw 5,IFRAME_INTR_DEPTH(1); \
stw 4,IFRAME_SRR0(1); \
stw 3,IFRAME_SRR1(1); \
mfpid 0; /* get currect PID register */ \
stw 0,IFRAME_PID(1); \
li 0,KERNEL_PID; \
mtpid 0; \
/* interrupts are recoverable here, and enable translation */ \
mfmsr 5; \
ori 5,5,(PSL_IR|PSL_DR); \
mtmsr 5; \
isync
.globl _C_LABEL(extint_call)
extintr:
INTRENTER
_C_LABEL(extint_call):
bl _C_LABEL(extint_call) /* to be filled in later */
intr_exit:
/* Disable interrupts (should already be disabled) and MMU here: */
wrteei 0
isync
lwz 3,IFRAME_PID(1)
lwz 4,IFRAME_SRR1(1) /* Load srr1 */
bl _C_LABEL(ctx_setup) /* Get proper ctx */
mfmsr 5
lis 4,(PSL_EE|PSL_DR|PSL_IR)@h
ori 4,4,(PSL_EE|PSL_DR|PSL_IR)@l
andc 5,5,4
mtmsr 5
isync
mtpid 3 /* Load CTX */
/* restore possibly overwritten registers: */
lwz 12,IFRAME_R12(1)
lwz 11,IFRAME_R11(1)
lwz 10,IFRAME_R10(1)
lwz 9,IFRAME_R9(1)
lwz 8,IFRAME_R8(1)
lwz 7,IFRAME_R7(1)
lwz 6,IFRAME_SRR1(1)
lwz 5,IFRAME_SRR0(1)
lwz 4,IFRAME_CTR(1)
lwz 3,IFRAME_XER(1)
mtsrr1 6
mtsrr0 5
mtctr 4
mtxer 3
/* Returning to user mode? */
GET_CPUINFO(5)
lwz 4,CI_INTRDEPTH(5)
addi 4,4,-1 /* adjust reentrancy count */
stw 4,CI_INTRDEPTH(5)
mtcr 6 /* saved SRR1 */
bc 4,17,1f /* branch if PSL_PR is false */
lwz 4,CI_ASTPENDING(5) /* Test AST pending */
andi. 4,4,1
beq 1f
/* Setup for entry to realtrap: */
lwz 3,0(1) /* get saved SP */
mtsprg 1,3
li 6,EXC_AST
stmw 28,tempsave(0) /* establish tempsave again */
mtlr 6
lwz 28,IFRAME_LR(1) /* saved LR */
lwz 29,IFRAME_CR(1) /* saved CR */
lwz 6,IFRAME_R6(1)
lwz 5,IFRAME_R5(1)
lwz 4,IFRAME_R4(1)
lwz 3,IFRAME_R3(1)
lwz 0,IFRAME_R0(1)
b realtrap
1:
/* Here is the normal exit of extintr: */
lwz 5,IFRAME_CR(1)
lwz 6,IFRAME_LR(1)
mtcr 5
mtlr 6
lwz 6,IFRAME_R6(1)
lwz 5,IFRAME_R5(1)
lwz 4,IFRAME_R4(1)
lwz 3,IFRAME_R3(1)
lwz 0,IFRAME_R0(1)
lwz 1,IFRAME_R1(1)
rfi
ba . /* Protect against prefetch */
/*
* PIT interrupt handler.
*/
.align 5
_C_LABEL(pitint):
mtsprg 1,1 /* save SP */
stmw 28,tempsave(0) /* free r28-r31 */
mflr 28 /* save LR */
mfcr 29 /* save CR */
mfxer 30 /* save XER */
GET_CPUINFO(1)
lwz 31,CI_INTRDEPTH(1) /* were we already running on intstk? */
addic. 31,31,1
stw 31,CI_INTRDEPTH(1)
lwz 1,CI_INTSTK(1) /* get intstk */
beq 1f
mfsprg 1,1 /* yes, get old SP */
1:
INTRENTER
addi 3,1,8 /* intr frame */
bl _C_LABEL(decr_intr)
b intr_exit
/*
* FIT interrupt handler.
*/
.align 5
fitint:
mtsprg 1,1 /* save SP */
stmw 28,tempsave(0) /* free r28-r31 */
mflr 28 /* save LR */
mfcr 29 /* save CR */
mfxer 30 /* save XER */
GET_CPUINFO(1)
lwz 31,CI_INTRDEPTH(1) /* were we already running on intstk? */
addic. 31,31,1
stw 31,CI_INTRDEPTH(1)
lwz 1,CI_INTSTK(1) /* get intstk */
beq 1f
mfsprg 1,1 /* yes, get old SP */
1:
INTRENTER
addi 3,1,8 /* intr frame */
bl _C_LABEL(stat_intr)
b intr_exit
#if defined(DDB) || defined(KGDB)
/*
* Deliberate entry to ddbtrap
*/
.globl _C_LABEL(ddb_trap)
_C_LABEL(ddb_trap):
mtsprg 1,1
mfmsr 3
mtsrr1 3
wrteei 0 /* disable interrupts */
isync
stmw 28,ddbsave(0)
mflr 28
li 29,EXC_BPT
mtlr 29
mfcr 29
mtsrr0 28
/*
* Now the ddb/kgdb trap catching code.
*/
ddbtrap:
FRAME_SETUP(ddbsave)
/* Call C trap code: */
addi 3,1,8
bl _C_LABEL(ddb_trap_glue)
or. 3,3,3
bne ddbleave
/* This wasn't for DDB, so switch to real trap: */
lwz 3,FRAME_EXC+8(1) /* save exception */
stw 3,ddbsave+12(0)
FRAME_LEAVE(ddbsave)
mtsprg 1,1 /* prepare for entrance to realtrap */
stmw 28,tempsave(0)
mflr 28
mfcr 29
lwz 31,ddbsave+12(0)
mtlr 31
b realtrap
ddbleave:
FRAME_LEAVE(ddbsave)
rfi
ba . /* Protect against prefetch */
#endif /* DDB || KGDB */
#ifdef IPKDB
/*
* Deliberate entry to ipkdbtrap
*/
.globl _C_LABEL(ipkdb_trap)
_C_LABEL(ipkdb_trap):
mtsprg 1,1
mfmsr 3
mtsrr1 3
wrteei 0 /* disable interrupts */
isync
stmw 28,ipkdbsave(0)
mflr 28
li 29,EXC_BPT
mtlr 29
mfcr 29
mtsrr0 28
/*
* Now the ipkdb trap catching code.
*/
ipkdbtrap:
FRAME_SETUP(ipkdbsave)
/* Call C trap code: */
addi 3,1,8
bl _C_LABEL(ipkdb_trap_glue)
or. 3,3,3
bne ipkdbleave
/* This wasn't for IPKDB, so switch to real trap: */
lwz 3,FRAME_EXC+8(1) /* save exception */
stw 3,ipkdbsave+8(0)
FRAME_LEAVE(ipkdbsave)
mtsprg 1,1 /* prepare for entrance to realtrap */
stmw 28,tempsave(0)
mflr 28
mfcr 29
lwz 31,ipkdbsave+8(0)
mtlr 31
b realtrap
ipkdbleave:
FRAME_LEAVE(ipkdbsave)
rfi
ba . /* Protect against prefetch */
ipkdbfault:
ba _ipkdbfault
_ipkdbfault:
mfsrr0 3
addi 3,3,4
mtsrr0 3
li 3,-1
rfi
ba . /* Protect against prefetch */
/*
* int ipkdbfbyte(unsigned char *p)
*/
.globl _C_LABEL(ipkdbfbyte)
_C_LABEL(ipkdbfbyte):
li 9,EXC_DSI /* establish new fault routine */
lwz 5,0(9)
lis 6,ipkdbfault@ha
lwz 6,ipkdbfault@l(6)
stw 6,0(9)
#ifdef IPKDBUSERHACK
#ifndef PPC_IBM4XX
lis 8,_C_LABEL(ipkdbsr)@ha
lwz 8,_C_LABEL(ipkdbsr)@l(8)
mtsr USER_SR,8
isync
#endif
#endif
dcbst 0,9 /* flush data... */
sync
icbi 0,9 /* and instruction caches */
lbz 3,0(3) /* fetch data */
stw 5,0(9) /* restore previous fault handler */
dcbst 0,9 /* and flush data... */
sync
icbi 0,9 /* and instruction caches */
blr
/*
* int ipkdbsbyte(unsigned char *p, int c)
*/
.globl _C_LABEL(ipkdbsbyte)
_C_LABEL(ipkdbsbyte):
li 9,EXC_DSI /* establish new fault routine */
lwz 5,0(9)
lis 6,ipkdbfault@ha
lwz 6,ipkdbfault@l(6)
stw 6,0(9)
#ifdef IPKDBUSERHACK
#ifndef PPC_IBM4XX
lis 8,_C_LABEL(ipkdbsr)@ha
lwz 8,_C_LABEL(ipkdbsr)@l(8)
mtsr USER_SR,8
isync
#endif
#endif
dcbst 0,9 /* flush data... */
sync
icbi 0,9 /* and instruction caches */
mr 6,3
xor 3,3,3
stb 4,0(6)
dcbst 0,6 /* Now do appropriate flushes
to data... */
sync
icbi 0,6 /* and instruction caches */
stw 5,0(9) /* restore previous fault handler */
dcbst 0,9 /* and flush data... */
sync
icbi 0,9 /* and instruction caches */
blr
#endif /* IPKDB */