/* $FreeBSD$ */
/* $NetBSD: trap_subr.S,v 1.20 2002/04/22 23:20:08 kleink Exp $ */
/*-
* 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/aim/trap_subr.S>
*/
/*
* Save/restore segment registers
*/
#define RESTORE_SRS(pmap,sr) mtsr 0,sr; \
lwz sr,1*4(pmap); mtsr 1,sr; \
lwz sr,2*4(pmap); mtsr 2,sr; \
lwz sr,3*4(pmap); mtsr 3,sr; \
lwz sr,4*4(pmap); mtsr 4,sr; \
lwz sr,5*4(pmap); mtsr 5,sr; \
lwz sr,6*4(pmap); mtsr 6,sr; \
lwz sr,7*4(pmap); mtsr 7,sr; \
lwz sr,8*4(pmap); mtsr 8,sr; \
lwz sr,9*4(pmap); mtsr 9,sr; \
lwz sr,10*4(pmap); mtsr 10,sr; \
lwz sr,11*4(pmap); mtsr 11,sr; \
lwz sr,12*4(pmap); mtsr 12,sr; \
lwz sr,13*4(pmap); mtsr 13,sr; \
lwz sr,14*4(pmap); mtsr 14,sr; \
lwz sr,15*4(pmap); mtsr 15,sr; isync;
/*
* User SRs are loaded through a pointer to the current pmap.
*/
#define RESTORE_USER_SRS(pmap,sr) \
GET_CPUINFO(pmap); \
lwz pmap,PC_CURPMAP(pmap); \
lwzu sr,PM_SR(pmap); \
RESTORE_SRS(pmap,sr)
/*
* Kernel SRs are loaded directly from kernel_pmap_
*/
#define RESTORE_KERN_SRS(pmap,sr) \
lis pmap,CNAME(kernel_pmap_store)@ha; \
lwzu sr,CNAME(kernel_pmap_store)+PM_SR@l(pmap); \
RESTORE_SRS(pmap,sr)
/*
* FRAME_SETUP assumes:
* SPRG1 SP (1)
* SPRG3 trap type
* savearea r28-r31,DAR,DSISR (DAR & DSISR only for DSI traps)
* r28 LR
* r29 CR
* r30 scratch
* r31 scratch
* r1 kernel stack
* SRR0/1 as at start of trap
*/
#define FRAME_SETUP(savearea) \
/* Have to enable translation to allow access of kernel stack: */ \
GET_CPUINFO(%r31); \
mfsrr0 %r30; \
stw %r30,(savearea+CPUSAVE_SRR0)(%r31); /* save SRR0 */ \
mfsrr1 %r30; \
stw %r30,(savearea+CPUSAVE_SRR1)(%r31); /* save SRR1 */ \
mfmsr %r30; \
ori %r30,%r30,(PSL_DR|PSL_IR|PSL_RI)@l; /* relocation on */ \
mtmsr %r30; /* stack can now be accessed */ \
isync; \
mfsprg1 %r31; /* get saved SP */ \
stwu %r31,-FRAMELEN(%r1); /* save it in the callframe */ \
stw %r0, FRAME_0+8(%r1); /* save r0 in the trapframe */ \
stw %r31,FRAME_1+8(%r1); /* save SP " " */ \
stw %r2, FRAME_2+8(%r1); /* save r2 " " */ \
stw %r28,FRAME_LR+8(%r1); /* save LR " " */ \
stw %r29,FRAME_CR+8(%r1); /* save CR " " */ \
GET_CPUINFO(%r2); \
lwz %r28,(savearea+CPUSAVE_R28)(%r2); /* get saved r28 */ \
lwz %r29,(savearea+CPUSAVE_R29)(%r2); /* get saved r29 */ \
lwz %r30,(savearea+CPUSAVE_R30)(%r2); /* get saved r30 */ \
lwz %r31,(savearea+CPUSAVE_R31)(%r2); /* get saved r31 */ \
stw %r3, FRAME_3+8(%r1); /* save r3-r31 */ \
stw %r4, FRAME_4+8(%r1); \
stw %r5, FRAME_5+8(%r1); \
stw %r6, FRAME_6+8(%r1); \
stw %r7, FRAME_7+8(%r1); \
stw %r8, FRAME_8+8(%r1); \
stw %r9, FRAME_9+8(%r1); \
stw %r10, FRAME_10+8(%r1); \
stw %r11, FRAME_11+8(%r1); \
stw %r12, FRAME_12+8(%r1); \
stw %r13, FRAME_13+8(%r1); \
stw %r14, FRAME_14+8(%r1); \
stw %r15, FRAME_15+8(%r1); \
stw %r16, FRAME_16+8(%r1); \
stw %r17, FRAME_17+8(%r1); \
stw %r18, FRAME_18+8(%r1); \
stw %r19, FRAME_19+8(%r1); \
stw %r20, FRAME_20+8(%r1); \
stw %r21, FRAME_21+8(%r1); \
stw %r22, FRAME_22+8(%r1); \
stw %r23, FRAME_23+8(%r1); \
stw %r24, FRAME_24+8(%r1); \
stw %r25, FRAME_25+8(%r1); \
stw %r26, FRAME_26+8(%r1); \
stw %r27, FRAME_27+8(%r1); \
stw %r28, FRAME_28+8(%r1); \
stw %r29, FRAME_29+8(%r1); \
stw %r30, FRAME_30+8(%r1); \
stw %r31, FRAME_31+8(%r1); \
lwz %r28,(savearea+CPUSAVE_AIM_DAR)(%r2); /* saved DAR */ \
lwz %r29,(savearea+CPUSAVE_AIM_DSISR)(%r2);/* saved DSISR */\
lwz %r30,(savearea+CPUSAVE_SRR0)(%r2); /* saved SRR0 */ \
lwz %r31,(savearea+CPUSAVE_SRR1)(%r2); /* saved SRR1 */ \
mfxer %r3; \
mfctr %r4; \
mfsprg3 %r5; \
stw %r3, FRAME_XER+8(1); /* save xer/ctr/exc */ \
stw %r4, FRAME_CTR+8(1); \
stw %r5, FRAME_EXC+8(1); \
stw %r28,FRAME_AIM_DAR+8(1); \
stw %r29,FRAME_AIM_DSISR+8(1); /* save dsisr/srr0/srr1 */ \
stw %r30,FRAME_SRR0+8(1); \
stw %r31,FRAME_SRR1+8(1)
#define FRAME_LEAVE(savearea) \
/* Now restore regs: */ \
lwz %r2,FRAME_SRR0+8(%r1); \
lwz %r3,FRAME_SRR1+8(%r1); \
lwz %r4,FRAME_CTR+8(%r1); \
lwz %r5,FRAME_XER+8(%r1); \
lwz %r6,FRAME_LR+8(%r1); \
GET_CPUINFO(%r7); \
stw %r2,(savearea+CPUSAVE_SRR0)(%r7); /* save SRR0 */ \
stw %r3,(savearea+CPUSAVE_SRR1)(%r7); /* save SRR1 */ \
lwz %r7,FRAME_CR+8(%r1); \
mtctr %r4; \
mtxer %r5; \
mtlr %r6; \
mtsprg1 %r7; /* save cr */ \
lwz %r31,FRAME_31+8(%r1); /* restore r0-31 */ \
lwz %r30,FRAME_30+8(%r1); \
lwz %r29,FRAME_29+8(%r1); \
lwz %r28,FRAME_28+8(%r1); \
lwz %r27,FRAME_27+8(%r1); \
lwz %r26,FRAME_26+8(%r1); \
lwz %r25,FRAME_25+8(%r1); \
lwz %r24,FRAME_24+8(%r1); \
lwz %r23,FRAME_23+8(%r1); \
lwz %r22,FRAME_22+8(%r1); \
lwz %r21,FRAME_21+8(%r1); \
lwz %r20,FRAME_20+8(%r1); \
lwz %r19,FRAME_19+8(%r1); \
lwz %r18,FRAME_18+8(%r1); \
lwz %r17,FRAME_17+8(%r1); \
lwz %r16,FRAME_16+8(%r1); \
lwz %r15,FRAME_15+8(%r1); \
lwz %r14,FRAME_14+8(%r1); \
lwz %r13,FRAME_13+8(%r1); \
lwz %r12,FRAME_12+8(%r1); \
lwz %r11,FRAME_11+8(%r1); \
lwz %r10,FRAME_10+8(%r1); \
lwz %r9, FRAME_9+8(%r1); \
lwz %r8, FRAME_8+8(%r1); \
lwz %r7, FRAME_7+8(%r1); \
lwz %r6, FRAME_6+8(%r1); \
lwz %r5, FRAME_5+8(%r1); \
lwz %r4, FRAME_4+8(%r1); \
lwz %r3, FRAME_3+8(%r1); \
lwz %r2, FRAME_2+8(%r1); \
lwz %r0, FRAME_0+8(%r1); \
lwz %r1, FRAME_1+8(%r1); \
/* Can't touch %r1 from here on */ \
mtsprg2 %r2; /* save r2 & r3 */ \
mtsprg3 %r3; \
/* Disable translation, machine check and recoverability: */ \
mfmsr %r2; \
andi. %r2,%r2,~(PSL_DR|PSL_IR|PSL_EE|PSL_ME|PSL_RI)@l; \
mtmsr %r2; \
isync; \
/* Decide whether we return to user mode: */ \
GET_CPUINFO(%r2); \
lwz %r3,(savearea+CPUSAVE_SRR1)(%r2); \
mtcr %r3; \
bf 17,1f; /* branch if PSL_PR is false */ \
/* Restore user SRs */ \
RESTORE_USER_SRS(%r2,%r3); \
1: mfsprg1 %r2; /* restore cr */ \
mtcr %r2; \
GET_CPUINFO(%r2); \
lwz %r3,(savearea+CPUSAVE_SRR0)(%r2); /* restore srr0 */ \
mtsrr0 %r3; \
lwz %r3,(savearea+CPUSAVE_SRR1)(%r2); /* restore srr1 */ \
mtsrr1 %r3; \
mfsprg2 %r2; /* restore r2 & r3 */ \
mfsprg3 %r3
#ifdef SMP
/*
* Processor reset exception handler. These are typically
* the first instructions the processor executes after a
* software reset.
*/
.globl CNAME(rstcode), CNAME(rstsize)
CNAME(rstcode):
bl 1f
.space 124
1:
mflr %r1
addi %r1,%r1,(124-16)@l
lis %r3,1@l
bla CNAME(pmap_cpu_bootstrap)
bla CNAME(cpudep_ap_bootstrap)
mr %r1,%r3
bla CNAME(machdep_ap_bootstrap)
/* Should not be reached */
9:
b 9b
CNAME(rstsize) = . - CNAME(rstcode)
#endif
/*
* This code gets copied to all the trap vectors
* (except ISI/DSI, ALI, and the interrupts)
*/
.globl CNAME(trapcode),CNAME(trapsize)
CNAME(trapcode):
mtsprg1 %r1 /* save SP */
mflr %r1 /* Save the old LR in r1 */
mtsprg2 %r1 /* And then in SPRG2 */
li %r1, 0x20 /* How to get the vector from LR */
bla generictrap /* LR & SPRG3 is exception # */
CNAME(trapsize) = .-CNAME(trapcode)
/*
* For ALI: has to save DSISR and DAR
*/
.globl CNAME(alitrap),CNAME(alisize)
CNAME(alitrap):
mtsprg1 %r1 /* save SP */
GET_CPUINFO(%r1)
stw %r28,(PC_TEMPSAVE+CPUSAVE_R28)(%r1) /* free r28-r31 */
stw %r29,(PC_TEMPSAVE+CPUSAVE_R29)(%r1)
stw %r30,(PC_TEMPSAVE+CPUSAVE_R30)(%r1)
stw %r31,(PC_TEMPSAVE+CPUSAVE_R31)(%r1)
mfdar %r30
mfdsisr %r31
stw %r30,(PC_TEMPSAVE+CPUSAVE_AIM_DAR)(%r1)
stw %r31,(PC_TEMPSAVE+CPUSAVE_AIM_DSISR)(%r1)
mfsprg1 %r1 /* restore SP, in case of branch */
mflr %r28 /* save LR */
mfcr %r29 /* save CR */
/* Put our exception vector in SPRG0 */
li %r31, EXC_ALI
mtsprg3 %r31
/* Test whether we already had PR set */
mfsrr1 %r31
mtcr %r31
bla s_trap
CNAME(alisize) = .-CNAME(alitrap)
/*
* Similar to the above for DSI
* Has to handle BAT spills
* and standard pagetable spills
*/
.globl CNAME(dsitrap),CNAME(dsisize)
CNAME(dsitrap):
mtsprg1 %r1 /* save SP */
GET_CPUINFO(%r1)
stw %r28,(PC_DISISAVE+CPUSAVE_R28)(%r1) /* free r28-r31 */
stw %r29,(PC_DISISAVE+CPUSAVE_R29)(%r1)
stw %r30,(PC_DISISAVE+CPUSAVE_R30)(%r1)
stw %r31,(PC_DISISAVE+CPUSAVE_R31)(%r1)
mfsprg1 %r1 /* restore SP */
mfcr %r29 /* save CR */
mfxer %r30 /* save XER */
mtsprg2 %r30 /* in SPRG2 */
mfsrr1 %r31 /* test kernel mode */
mtcr %r31
bt 17,1f /* branch if PSL_PR is set */
mfdar %r31 /* get fault address */
rlwinm %r31,%r31,7,25,28 /* get segment * 8 */
/* get batu */
addis %r31,%r31,CNAME(battable)@ha
lwz %r30,CNAME(battable)@l(31)
mtcr %r30
bf 30,1f /* branch if supervisor valid is
false */
/* get batl */
lwz %r31,CNAME(battable)+4@l(31)
/* We randomly use the highest two bat registers here */
mftb %r28
andi. %r28,%r28,1
bne 2f
mtdbatu 2,%r30
mtdbatl 2,%r31
b 3f
2:
mtdbatu 3,%r30
mtdbatl 3,%r31
3:
mfsprg2 %r30 /* restore XER */
mtxer %r30
mtcr %r29 /* restore CR */
mtsprg1 %r1
GET_CPUINFO(%r1)
lwz %r28,(PC_DISISAVE+CPUSAVE_R28)(%r1) /* restore r28-r31 */
lwz %r29,(PC_DISISAVE+CPUSAVE_R29)(%r1)
lwz %r30,(PC_DISISAVE+CPUSAVE_R30)(%r1)
lwz %r31,(PC_DISISAVE+CPUSAVE_R31)(%r1)
mfsprg1 %r1
rfi /* return to trapped code */
1:
mflr %r28 /* save LR (SP already saved) */
bla disitrap
CNAME(dsisize) = .-CNAME(dsitrap)
/*
* Preamble code for DSI/ISI traps
*/
disitrap:
/* Write the trap vector to SPRG0 by computing LR & 0xff00 */
mflr %r1
andi. %r1,%r1,0xff00
mtsprg3 %r1
GET_CPUINFO(%r1)
lwz %r30,(PC_DISISAVE+CPUSAVE_R28)(%r1)
stw %r30,(PC_TEMPSAVE+CPUSAVE_R28)(%r1)
lwz %r31,(PC_DISISAVE+CPUSAVE_R29)(%r1)
stw %r31,(PC_TEMPSAVE+CPUSAVE_R29)(%r1)
lwz %r30,(PC_DISISAVE+CPUSAVE_R30)(%r1)
stw %r30,(PC_TEMPSAVE+CPUSAVE_R30)(%r1)
lwz %r31,(PC_DISISAVE+CPUSAVE_R31)(%r1)
stw %r31,(PC_TEMPSAVE+CPUSAVE_R31)(%r1)
mfdar %r30
mfdsisr %r31
stw %r30,(PC_TEMPSAVE+CPUSAVE_AIM_DAR)(%r1)
stw %r31,(PC_TEMPSAVE+CPUSAVE_AIM_DSISR)(%r1)
#ifdef KDB
/* Try and detect a kernel stack overflow */
mfsrr1 %r31
mtcr %r31
bt 17,realtrap /* branch is user mode */
mfsprg1 %r31 /* get old SP */
sub. %r30,%r31,%r30 /* SP - DAR */
bge 1f
neg %r30,%r30 /* modulo value */
1: cmplwi %cr0,%r30,4096 /* is DAR within a page of SP? */
bge %cr0,realtrap /* no, too far away. */
/* Now convert this DSI into a DDB trap. */
GET_CPUINFO(%r1)
lwz %r30,(PC_TEMPSAVE+CPUSAVE_AIM_DAR)(%r1) /* get DAR */
stw %r30,(PC_DBSAVE +CPUSAVE_AIM_DAR)(%r1) /* save DAR */
lwz %r30,(PC_TEMPSAVE+CPUSAVE_AIM_DSISR)(%r1) /* get DSISR */
lwz %r30,(PC_DBSAVE +CPUSAVE_AIM_DSISR)(%r1) /* save DSISR */
lwz %r30,(PC_DISISAVE+CPUSAVE_R28)(%r1) /* get r28 */
stw %r30,(PC_DBSAVE +CPUSAVE_R28)(%r1) /* save r28 */
lwz %r31,(PC_DISISAVE+CPUSAVE_R29)(%r1) /* get r29 */
stw %r31,(PC_DBSAVE +CPUSAVE_R29)(%r1) /* save r29 */
lwz %r30,(PC_DISISAVE+CPUSAVE_R30)(%r1) /* get r30 */
stw %r30,(PC_DBSAVE +CPUSAVE_R30)(%r1) /* save r30 */
lwz %r31,(PC_DISISAVE+CPUSAVE_R31)(%r1) /* get r31 */
stw %r31,(PC_DBSAVE +CPUSAVE_R31)(%r1) /* save r31 */
lis %r1,(tmpstk+TMPSTKSZ-16)@ha /* get new SP */
addi %r1,%r1,(tmpstk+TMPSTKSZ-16)@l
b dbtrap
#endif
/* XXX need stack probe here */
realtrap:
/* Test whether we already had PR set */
mfsrr1 %r1
mtcr %r1
mfsprg1 %r1 /* restore SP (might have been
overwritten) */
bf 17,k_trap /* branch if PSL_PR is false */
GET_CPUINFO(%r1)
lwz %r1,PC_CURPCB(%r1)
RESTORE_KERN_SRS(%r30,%r31) /* enable kernel mapping */
ba s_trap
/*
* generictrap does some standard setup for trap handling to minimize
* the code that need be installed in the actual vectors. It expects
* the following conditions.
*
* R1 - Trap vector = LR & (0xff00 | R1)
* SPRG1 - Original R1 contents
* SPRG2 - Original LR
*/
generictrap:
/* Save R1 for computing the exception vector */
mtsprg3 %r1
/* Save interesting registers */
GET_CPUINFO(%r1)
stw %r28,(PC_TEMPSAVE+CPUSAVE_R28)(%r1) /* free r28-r31 */
stw %r29,(PC_TEMPSAVE+CPUSAVE_R29)(%r1)
stw %r30,(PC_TEMPSAVE+CPUSAVE_R30)(%r1)
stw %r31,(PC_TEMPSAVE+CPUSAVE_R31)(%r1)
mfsprg1 %r1 /* restore SP, in case of branch */
mfsprg2 %r28 /* save LR */
mfcr %r29 /* save CR */
/* Compute the exception vector from the link register */
mfsprg3 %r31
ori %r31,%r31,0xff00
mflr %r30
and %r30,%r30,%r31
mtsprg3 %r30
/* Test whether we already had PR set */
mfsrr1 %r31
mtcr %r31
s_trap:
bf 17,k_trap /* branch if PSL_PR is false */
GET_CPUINFO(%r1)
u_trap:
lwz %r1,PC_CURPCB(%r1)
RESTORE_KERN_SRS(%r30,%r31) /* enable kernel mapping */
/*
* Now the common trap catching code.
*/
k_trap:
FRAME_SETUP(PC_TEMPSAVE)
/* Call C interrupt dispatcher: */
trapagain:
addi %r3,%r1,8
bl CNAME(powerpc_interrupt)
.globl CNAME(trapexit) /* backtrace code sentinel */
CNAME(trapexit):
/* Disable interrupts: */
mfmsr %r3
andi. %r3,%r3,~PSL_EE@l
mtmsr %r3
/* Test AST pending: */
lwz %r5,FRAME_SRR1+8(%r1)
mtcr %r5
bf 17,1f /* branch if PSL_PR is false */
GET_CPUINFO(%r3) /* get per-CPU pointer */
lwz %r4, PC_CURTHREAD(%r3) /* deref to get curthread */
lwz %r4, TD_FLAGS(%r4) /* get thread flags value */
lis %r5, (TDF_ASTPENDING|TDF_NEEDRESCHED)@h
ori %r5,%r5, (TDF_ASTPENDING|TDF_NEEDRESCHED)@l
and. %r4,%r4,%r5
beq 1f
mfmsr %r3 /* re-enable interrupts */
ori %r3,%r3,PSL_EE@l
mtmsr %r3
isync
addi %r3,%r1,8
bl CNAME(ast)
.globl CNAME(asttrapexit) /* backtrace code sentinel #2 */
CNAME(asttrapexit):
b trapexit /* test ast ret value ? */
1:
FRAME_LEAVE(PC_TEMPSAVE)
rfi
#if defined(KDB)
/*
* Deliberate entry to dbtrap
*/
.globl CNAME(breakpoint)
CNAME(breakpoint):
mtsprg1 %r1
mfmsr %r3
mtsrr1 %r3
andi. %r3,%r3,~(PSL_EE|PSL_ME)@l
mtmsr %r3 /* disable interrupts */
isync
GET_CPUINFO(%r3)
stw %r28,(PC_DBSAVE+CPUSAVE_R28)(%r3)
stw %r29,(PC_DBSAVE+CPUSAVE_R29)(%r3)
stw %r30,(PC_DBSAVE+CPUSAVE_R30)(%r3)
stw %r31,(PC_DBSAVE+CPUSAVE_R31)(%r3)
mflr %r28
li %r29,EXC_BPT
mtlr %r29
mfcr %r29
mtsrr0 %r28
/*
* Now the kdb trap catching code.
*/
dbtrap:
/* Write the trap vector to SPRG0 by computing LR & 0xff00 */
mflr %r1
andi. %r1,%r1,0xff00
mtsprg3 %r1
lis %r1,(tmpstk+TMPSTKSZ-16)@ha /* get new SP */
addi %r1,%r1,(tmpstk+TMPSTKSZ-16)@l
FRAME_SETUP(PC_DBSAVE)
/* Call C trap code: */
addi %r3,%r1,8
bl CNAME(db_trap_glue)
or. %r3,%r3,%r3
bne dbleave
/* This wasn't for KDB, so switch to real trap: */
lwz %r3,FRAME_EXC+8(%r1) /* save exception */
GET_CPUINFO(%r4)
stw %r3,(PC_DBSAVE+CPUSAVE_R31)(%r4)
FRAME_LEAVE(PC_DBSAVE)
mtsprg1 %r1 /* prepare for entrance to realtrap */
GET_CPUINFO(%r1)
stw %r28,(PC_TEMPSAVE+CPUSAVE_R28)(%r1)
stw %r29,(PC_TEMPSAVE+CPUSAVE_R29)(%r1)
stw %r30,(PC_TEMPSAVE+CPUSAVE_R30)(%r1)
stw %r31,(PC_TEMPSAVE+CPUSAVE_R31)(%r1)
mflr %r28
mfcr %r29
lwz %r31,(PC_DBSAVE+CPUSAVE_R31)(%r1)
mtlr %r31
mfsprg1 %r1
b realtrap
dbleave:
FRAME_LEAVE(PC_DBSAVE)
rfi
/*
* In case of KDB we want a separate trap catcher for it
*/
.globl CNAME(dblow),CNAME(dbsize)
CNAME(dblow):
mtsprg1 %r1 /* save SP */
mtsprg2 %r29 /* save r29 */
mfcr %r29 /* save CR in r29 */
mfsrr1 %r1
mtcr %r1
bf 17,1f /* branch if privileged */
/* Unprivileged case */
mtcr %r29 /* put the condition register back */
mfsprg2 %r29 /* ... and r29 */
mflr %r1 /* save LR */
mtsprg2 %r1 /* And then in SPRG2 */
li %r1, 0 /* How to get the vector from LR */
bla generictrap /* and we look like a generic trap */
1:
/* Privileged, so drop to KDB */
GET_CPUINFO(%r1)
stw %r28,(PC_DBSAVE+CPUSAVE_R28)(%r1) /* free r28 */
mfsprg2 %r28 /* r29 holds cr... */
stw %r28,(PC_DBSAVE+CPUSAVE_R29)(%r1) /* free r29 */
stw %r30,(PC_DBSAVE+CPUSAVE_R30)(%r1) /* free r30 */
stw %r31,(PC_DBSAVE+CPUSAVE_R31)(%r1) /* free r31 */
mflr %r28 /* save LR */
bla dbtrap
CNAME(dbsize) = .-CNAME(dblow)
#endif /* KDB */
