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freebsd-dev/sys/powerpc/booke/trap_subr.S
Justin Hibbits 64a982ea56 Migrate the PTE format for book-e to standardize on the 'indirect PTE' format 
Summary:
The revised Book-E spec, adding the specification for the MMUv2 and e6500,
includes a hardware PTE layout for indirect page tables.  In order to support
this in the future, migrate the PTE format to match the MMUv2 hardware PTE
format.

Test Plan: Boot tested on a P5020 board.  Booted to multiuser mode.

Differential Revision: https://reviews.freebsd.org/D5224
2016-02-11 13:15:37 +00:00

964 lines
28 KiB
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/*-
* Copyright (C) 2006-2009 Semihalf, Rafal Jaworowski <raj@semihalf.com>
* Copyright (C) 2006 Semihalf, Marian Balakowicz <m8@semihalf.com>
* Copyright (C) 2006 Juniper Networks, Inc.
* 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. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 THE AUTHOR 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.
*
* $FreeBSD$
*/
/*-
* 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.
*
* from: $NetBSD: trap_subr.S,v 1.20 2002/04/22 23:20:08 kleink Exp $
*/
/*
* NOTICE: This is not a standalone file. to use it, #include it in
* your port's locore.S, like so:
*
* #include <powerpc/booke/trap_subr.S>
*/
/*
* SPRG usage notes
*
* SPRG0 - pcpu pointer
* SPRG1 - all interrupts except TLB miss, critical, machine check
* SPRG2 - critical
* SPRG3 - machine check
* SPRG4-6 - scratch
*
*/
/* Get the per-CPU data structure */
#define GET_CPUINFO(r) mfsprg0 r
#define RES_GRANULE 32
#define RES_LOCK 0 /* offset to the 'lock' word */
#define RES_RECURSE 4 /* offset to the 'recurse' word */
/*
* Standard interrupt prolog
*
* sprg_sp - SPRG{1-3} reg used to temporarily store the SP
* savearea - temp save area (pc_{tempsave, disisave, critsave, mchksave})
* isrr0-1 - save restore registers with CPU state at interrupt time (may be
* SRR0-1, CSRR0-1, MCSRR0-1
*
* 1. saves in the given savearea:
* - R30-31
* - DEAR, ESR
* - xSRR0-1
*
* 2. saves CR -> R30
*
* 3. switches to kstack if needed
*
* 4. notes:
* - R31 can be used as scratch register until a new frame is layed on
* the stack with FRAME_SETUP
*
* - potential TLB miss: NO. Saveareas are always acessible via TLB1
* permanent entries, and within this prolog we do not dereference any
* locations potentially not in the TLB
*/
#define STANDARD_PROLOG(sprg_sp, savearea, isrr0, isrr1) \
mtspr sprg_sp, %r1; /* Save SP */ \
GET_CPUINFO(%r1); /* Per-cpu structure */ \
stw %r30, (savearea+CPUSAVE_R30)(%r1); \
stw %r31, (savearea+CPUSAVE_R31)(%r1); \
mfdear %r30; \
mfesr %r31; \
stw %r30, (savearea+CPUSAVE_BOOKE_DEAR)(%r1); \
stw %r31, (savearea+CPUSAVE_BOOKE_ESR)(%r1); \
mfspr %r30, isrr0; \
mfspr %r31, isrr1; /* MSR at interrupt time */ \
stw %r30, (savearea+CPUSAVE_SRR0)(%r1); \
stw %r31, (savearea+CPUSAVE_SRR1)(%r1); \
isync; \
mfspr %r1, sprg_sp; /* Restore SP */ \
mfcr %r30; /* Save CR */ \
/* switch to per-thread kstack if intr taken in user mode */ \
mtcr %r31; /* MSR at interrupt time */ \
bf 17, 1f; \
GET_CPUINFO(%r1); /* Per-cpu structure */ \
lwz %r1, PC_CURPCB(%r1); /* Per-thread kernel stack */ \
1:
#define STANDARD_CRIT_PROLOG(sprg_sp, savearea, isrr0, isrr1) \
mtspr sprg_sp, %r1; /* Save SP */ \
GET_CPUINFO(%r1); /* Per-cpu structure */ \
stw %r30, (savearea+CPUSAVE_R30)(%r1); \
stw %r31, (savearea+CPUSAVE_R31)(%r1); \
mfdear %r30; \
mfesr %r31; \
stw %r30, (savearea+CPUSAVE_BOOKE_DEAR)(%r1); \
stw %r31, (savearea+CPUSAVE_BOOKE_ESR)(%r1); \
mfspr %r30, isrr0; \
mfspr %r31, isrr1; /* MSR at interrupt time */ \
stw %r30, (savearea+CPUSAVE_SRR0)(%r1); \
stw %r31, (savearea+CPUSAVE_SRR1)(%r1); \
mfspr %r30, SPR_SRR0; \
mfspr %r31, SPR_SRR1; /* MSR at interrupt time */ \
stw %r30, (savearea+CPUSAVE_SRR0+8)(%r1); \
stw %r31, (savearea+CPUSAVE_SRR1+8)(%r1); \
isync; \
mfspr %r1, sprg_sp; /* Restore SP */ \
mfcr %r30; /* Save CR */ \
/* switch to per-thread kstack if intr taken in user mode */ \
mtcr %r31; /* MSR at interrupt time */ \
bf 17, 1f; \
GET_CPUINFO(%r1); /* Per-cpu structure */ \
lwz %r1, PC_CURPCB(%r1); /* Per-thread kernel stack */ \
1:
/*
* FRAME_SETUP assumes:
* SPRG{1-3} SP at the time interrupt occured
* savearea r30-r31, DEAR, ESR, xSRR0-1
* r30 CR
* r31 scratch
* r1 kernel stack
*
* sprg_sp - SPRG reg containing SP at the time interrupt occured
* savearea - temp save
* exc - exception number (EXC_xxx)
*
* 1. sets a new frame
* 2. saves in the frame:
* - R0, R1 (SP at the time of interrupt), R2, LR, CR
* - R3-31 (R30-31 first restored from savearea)
* - XER, CTR, DEAR, ESR (from savearea), xSRR0-1
*
* Notes:
* - potential TLB miss: YES, since we make dereferences to kstack, which
* can happen not covered (we can have up to two DTLB misses if fortunate
* enough i.e. when kstack crosses page boundary and both pages are
* untranslated)
*/
#define FRAME_SETUP(sprg_sp, savearea, exc) \
mfspr %r31, sprg_sp; /* get saved SP */ \
/* establish a new stack frame and put everything on it */ \
stwu %r31, -FRAMELEN(%r1); \
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 " " */ \
mflr %r31; \
stw %r31, FRAME_LR+8(%r1); /* save LR " " */ \
stw %r30, FRAME_CR+8(%r1); /* save CR " " */ \
GET_CPUINFO(%r2); \
lwz %r30, (savearea+CPUSAVE_R30)(%r2); /* get saved r30 */ \
lwz %r31, (savearea+CPUSAVE_R31)(%r2); /* get saved r31 */ \
/* save R3-31 */ \
stmw %r3, FRAME_3+8(%r1) ; \
/* save DEAR, ESR */ \
lwz %r28, (savearea+CPUSAVE_BOOKE_DEAR)(%r2); \
lwz %r29, (savearea+CPUSAVE_BOOKE_ESR)(%r2); \
stw %r28, FRAME_BOOKE_DEAR+8(%r1); \
stw %r29, FRAME_BOOKE_ESR+8(%r1); \
/* save XER, CTR, exc number */ \
mfxer %r3; \
mfctr %r4; \
stw %r3, FRAME_XER+8(%r1); \
stw %r4, FRAME_CTR+8(%r1); \
li %r5, exc; \
stw %r5, FRAME_EXC+8(%r1); \
/* save DBCR0 */ \
mfspr %r3, SPR_DBCR0; \
stw %r3, FRAME_BOOKE_DBCR0+8(%r1); \
/* save xSSR0-1 */ \
lwz %r30, (savearea+CPUSAVE_SRR0)(%r2); \
lwz %r31, (savearea+CPUSAVE_SRR1)(%r2); \
stw %r30, FRAME_SRR0+8(%r1); \
stw %r31, FRAME_SRR1+8(%r1); \
lwz %r2,PC_CURTHREAD(%r2) /* set curthread pointer */
/*
*
* isrr0-1 - save restore registers to restore CPU state to (may be
* SRR0-1, CSRR0-1, MCSRR0-1
*
* Notes:
* - potential TLB miss: YES. The deref'd kstack may be not covered
*/
#define FRAME_LEAVE(isrr0, isrr1) \
/* restore CTR, XER, LR, CR */ \
lwz %r4, FRAME_CTR+8(%r1); \
lwz %r5, FRAME_XER+8(%r1); \
lwz %r6, FRAME_LR+8(%r1); \
lwz %r7, FRAME_CR+8(%r1); \
mtctr %r4; \
mtxer %r5; \
mtlr %r6; \
mtcr %r7; \
/* restore DBCR0 */ \
lwz %r4, FRAME_BOOKE_DBCR0+8(%r1); \
mtspr SPR_DBCR0, %r4; \
/* restore xSRR0-1 */ \
lwz %r30, FRAME_SRR0+8(%r1); \
lwz %r31, FRAME_SRR1+8(%r1); \
mtspr isrr0, %r30; \
mtspr isrr1, %r31; \
/* restore R2-31, SP */ \
lmw %r2, FRAME_2+8(%r1) ; \
lwz %r0, FRAME_0+8(%r1); \
lwz %r1, FRAME_1+8(%r1); \
isync
/*
* TLB miss prolog
*
* saves LR, CR, SRR0-1, R20-31 in the TLBSAVE area
*
* Notes:
* - potential TLB miss: NO. It is crucial that we do not generate a TLB
* miss within the TLB prolog itself!
* - TLBSAVE is always translated
*/
#define TLB_PROLOG \
mtsprg4 %r1; /* Save SP */ \
mtsprg5 %r28; \
mtsprg6 %r29; \
/* calculate TLB nesting level and TLBSAVE instance address */ \
GET_CPUINFO(%r1); /* Per-cpu structure */ \
lwz %r28, PC_BOOKE_TLB_LEVEL(%r1); \
rlwinm %r29, %r28, 6, 23, 25; /* 4 x TLBSAVE_LEN */ \
addi %r28, %r28, 1; \
stw %r28, PC_BOOKE_TLB_LEVEL(%r1); \
addi %r29, %r29, PC_BOOKE_TLBSAVE@l; \
add %r1, %r1, %r29; /* current TLBSAVE ptr */ \
\
/* save R20-31 */ \
mfsprg5 %r28; \
mfsprg6 %r29; \
stmw %r20, (TLBSAVE_BOOKE_R20)(%r1); \
/* save LR, CR */ \
mflr %r30; \
mfcr %r31; \
stw %r30, (TLBSAVE_BOOKE_LR)(%r1); \
stw %r31, (TLBSAVE_BOOKE_CR)(%r1); \
/* save SRR0-1 */ \
mfsrr0 %r30; /* execution addr at interrupt time */ \
mfsrr1 %r31; /* MSR at interrupt time*/ \
stw %r30, (TLBSAVE_BOOKE_SRR0)(%r1); /* save SRR0 */ \
stw %r31, (TLBSAVE_BOOKE_SRR1)(%r1); /* save SRR1 */ \
isync; \
mfsprg4 %r1
/*
* restores LR, CR, SRR0-1, R20-31 from the TLBSAVE area
*
* same notes as for the TLB_PROLOG
*/
#define TLB_RESTORE \
mtsprg4 %r1; /* Save SP */ \
GET_CPUINFO(%r1); /* Per-cpu structure */ \
/* calculate TLB nesting level and TLBSAVE instance addr */ \
lwz %r28, PC_BOOKE_TLB_LEVEL(%r1); \
subi %r28, %r28, 1; \
stw %r28, PC_BOOKE_TLB_LEVEL(%r1); \
rlwinm %r29, %r28, 6, 23, 25; /* 4 x TLBSAVE_LEN */ \
addi %r29, %r29, PC_BOOKE_TLBSAVE@l; \
add %r1, %r1, %r29; \
\
/* restore LR, CR */ \
lwz %r30, (TLBSAVE_BOOKE_LR)(%r1); \
lwz %r31, (TLBSAVE_BOOKE_CR)(%r1); \
mtlr %r30; \
mtcr %r31; \
/* restore SRR0-1 */ \
lwz %r30, (TLBSAVE_BOOKE_SRR0)(%r1); \
lwz %r31, (TLBSAVE_BOOKE_SRR1)(%r1); \
mtsrr0 %r30; \
mtsrr1 %r31; \
/* restore R20-31 */ \
lmw %r20, (TLBSAVE_BOOKE_R20)(%r1); \
mfsprg4 %r1
#ifdef SMP
#define TLB_LOCK \
GET_CPUINFO(%r20); \
lwz %r21, PC_CURTHREAD(%r20); \
lwz %r22, PC_BOOKE_TLB_LOCK(%r20); \
\
1: lwarx %r23, 0, %r22; \
cmpwi %r23, TLB_UNLOCKED; \
beq 2f; \
\
/* check if this is recursion */ \
cmplw cr0, %r21, %r23; \
bne- 1b; \
\
2: /* try to acquire lock */ \
stwcx. %r21, 0, %r22; \
bne- 1b; \
\
/* got it, update recursion counter */ \
lwz %r21, RES_RECURSE(%r22); \
addi %r21, %r21, 1; \
stw %r21, RES_RECURSE(%r22); \
isync; \
msync
#define TLB_UNLOCK \
GET_CPUINFO(%r20); \
lwz %r21, PC_CURTHREAD(%r20); \
lwz %r22, PC_BOOKE_TLB_LOCK(%r20); \
\
/* update recursion counter */ \
lwz %r23, RES_RECURSE(%r22); \
subi %r23, %r23, 1; \
stw %r23, RES_RECURSE(%r22); \
\
cmpwi %r23, 0; \
bne 1f; \
isync; \
msync; \
\
/* release the lock */ \
li %r23, TLB_UNLOCKED; \
stw %r23, 0(%r22); \
1: isync; \
msync
#else
#define TLB_LOCK
#define TLB_UNLOCK
#endif /* SMP */
#define INTERRUPT(label) \
.globl label; \
.align 5; \
CNAME(label):
/*
* Interrupt handling routines in BookE can be flexibly placed and do not have
* to live in pre-defined vectors location. Note they need to be TLB-mapped at
* all times in order to be able to handle exceptions. We thus arrange for
* them to be part of kernel text which is always TLB-accessible.
*
* The interrupt handling routines have to be 16 bytes aligned: we align them
* to 32 bytes (cache line length) which supposedly performs better.
*
*/
.text
.globl CNAME(interrupt_vector_base)
.align 5
interrupt_vector_base:
/*****************************************************************************
* Catch-all handler to handle uninstalled IVORs
****************************************************************************/
INTERRUPT(int_unknown)
STANDARD_PROLOG(SPR_SPRG1, PC_TEMPSAVE, SPR_SRR0, SPR_SRR1)
FRAME_SETUP(SPR_SPRG1, PC_TEMPSAVE, EXC_RSVD)
b trap_common
/*****************************************************************************
* Critical input interrupt
****************************************************************************/
INTERRUPT(int_critical_input)
STANDARD_CRIT_PROLOG(SPR_SPRG2, PC_BOOKE_CRITSAVE, SPR_CSRR0, SPR_CSRR1)
FRAME_SETUP(SPR_SPRG2, PC_BOOKE_CRITSAVE, EXC_CRIT)
addi %r3, %r1, 8
bl CNAME(powerpc_interrupt)
FRAME_LEAVE(SPR_CSRR0, SPR_CSRR1)
rfci
/*****************************************************************************
* Machine check interrupt
****************************************************************************/
INTERRUPT(int_machine_check)
STANDARD_PROLOG(SPR_SPRG3, PC_BOOKE_MCHKSAVE, SPR_MCSRR0, SPR_MCSRR1)
FRAME_SETUP(SPR_SPRG3, PC_BOOKE_MCHKSAVE, EXC_MCHK)
addi %r3, %r1, 8
bl CNAME(powerpc_interrupt)
FRAME_LEAVE(SPR_MCSRR0, SPR_MCSRR1)
rfmci
/*****************************************************************************
* Data storage interrupt
****************************************************************************/
INTERRUPT(int_data_storage)
STANDARD_PROLOG(SPR_SPRG1, PC_DISISAVE, SPR_SRR0, SPR_SRR1)
FRAME_SETUP(SPR_SPRG1, PC_DISISAVE, EXC_DSI)
b trap_common
/*****************************************************************************
* Instruction storage interrupt
****************************************************************************/
INTERRUPT(int_instr_storage)
STANDARD_PROLOG(SPR_SPRG1, PC_TEMPSAVE, SPR_SRR0, SPR_SRR1)
FRAME_SETUP(SPR_SPRG1, PC_TEMPSAVE, EXC_ISI)
b trap_common
/*****************************************************************************
* External input interrupt
****************************************************************************/
INTERRUPT(int_external_input)
STANDARD_PROLOG(SPR_SPRG1, PC_TEMPSAVE, SPR_SRR0, SPR_SRR1)
FRAME_SETUP(SPR_SPRG1, PC_TEMPSAVE, EXC_EXI)
addi %r3, %r1, 8
bl CNAME(powerpc_interrupt)
b clear_we
INTERRUPT(int_alignment)
STANDARD_PROLOG(SPR_SPRG1, PC_TEMPSAVE, SPR_SRR0, SPR_SRR1)
FRAME_SETUP(SPR_SPRG1, PC_TEMPSAVE, EXC_ALI)
b trap_common
INTERRUPT(int_program)
STANDARD_PROLOG(SPR_SPRG1, PC_TEMPSAVE, SPR_SRR0, SPR_SRR1)
FRAME_SETUP(SPR_SPRG1, PC_TEMPSAVE, EXC_PGM)
b trap_common
INTERRUPT(int_fpu)
STANDARD_PROLOG(SPR_SPRG1, PC_TEMPSAVE, SPR_SRR0, SPR_SRR1)
FRAME_SETUP(SPR_SPRG1, PC_TEMPSAVE, EXC_FPU)
b trap_common
/*****************************************************************************
* System call
****************************************************************************/
INTERRUPT(int_syscall)
STANDARD_PROLOG(SPR_SPRG1, PC_TEMPSAVE, SPR_SRR0, SPR_SRR1)
FRAME_SETUP(SPR_SPRG1, PC_TEMPSAVE, EXC_SC)
b trap_common
/*****************************************************************************
* Decrementer interrupt
****************************************************************************/
INTERRUPT(int_decrementer)
STANDARD_PROLOG(SPR_SPRG1, PC_TEMPSAVE, SPR_SRR0, SPR_SRR1)
FRAME_SETUP(SPR_SPRG1, PC_TEMPSAVE, EXC_DECR)
addi %r3, %r1, 8
bl CNAME(powerpc_interrupt)
b clear_we
/*****************************************************************************
* Fixed interval timer
****************************************************************************/
INTERRUPT(int_fixed_interval_timer)
STANDARD_PROLOG(SPR_SPRG1, PC_TEMPSAVE, SPR_SRR0, SPR_SRR1)
FRAME_SETUP(SPR_SPRG1, PC_TEMPSAVE, EXC_FIT)
b trap_common
/*****************************************************************************
* Watchdog interrupt
****************************************************************************/
INTERRUPT(int_watchdog)
STANDARD_PROLOG(SPR_SPRG1, PC_TEMPSAVE, SPR_SRR0, SPR_SRR1)
FRAME_SETUP(SPR_SPRG1, PC_TEMPSAVE, EXC_WDOG)
b trap_common
/*****************************************************************************
* Altivec Unavailable interrupt
****************************************************************************/
INTERRUPT(int_vec)
STANDARD_PROLOG(SPR_SPRG1, PC_TEMPSAVE, SPR_SRR0, SPR_SRR1)
FRAME_SETUP(SPR_SPRG1, PC_TEMPSAVE, EXC_VEC)
b trap_common
/*****************************************************************************
* Watchdog interrupt
****************************************************************************/
INTERRUPT(int_vecast)
STANDARD_PROLOG(SPR_SPRG1, PC_TEMPSAVE, SPR_SRR0, SPR_SRR1)
FRAME_SETUP(SPR_SPRG1, PC_TEMPSAVE, EXC_VECAST_E)
b trap_common
#ifdef HWPMC_HOOKS
/*****************************************************************************
* PMC Interrupt
****************************************************************************/
INTERRUPT(int_performance_counter)
STANDARD_PROLOG(SPR_SPRG3, PC_TEMPSAVE, SPR_SRR0, SPR_SRR1)
FRAME_SETUP(SPR_SPRG3, PC_TEMPSAVE, EXC_PERF)
addi %r3, %r1, 8
bl CNAME(powerpc_interrupt)
b trapexit
#endif
/*****************************************************************************
* Data TLB miss interrupt
*
* There can be nested TLB misses - while handling a TLB miss we reference
* data structures that may be not covered by translations. We support up to
* TLB_NESTED_MAX-1 nested misses.
*
* Registers use:
* r31 - dear
* r30 - unused
* r29 - saved mas0
* r28 - saved mas1
* r27 - saved mas2
* r26 - pmap address
* r25 - pte address
*
* r20:r23 - scratch registers
****************************************************************************/
INTERRUPT(int_data_tlb_error)
TLB_PROLOG
TLB_LOCK
mfdear %r31
/*
* Save MAS0-MAS2 registers. There might be another tlb miss during
* pte lookup overwriting current contents (which was hw filled).
*/
mfspr %r29, SPR_MAS0
mfspr %r28, SPR_MAS1
mfspr %r27, SPR_MAS2
/* Check faulting address. */
lis %r21, VM_MAXUSER_ADDRESS@h
ori %r21, %r21, VM_MAXUSER_ADDRESS@l
cmplw cr0, %r31, %r21
blt search_user_pmap
/* If it's kernel address, allow only supervisor mode misses. */
mfsrr1 %r21
mtcr %r21
bt 17, search_failed /* check MSR[PR] */
search_kernel_pmap:
/* Load r26 with kernel_pmap address */
bl 1f
.long kernel_pmap_store-.
1: mflr %r21
lwz %r26, 0(%r21)
add %r26, %r21, %r26 /* kernel_pmap_store in r26 */
/* Force kernel tid, set TID to 0 in MAS1. */
li %r21, 0
rlwimi %r28, %r21, 0, 8, 15 /* clear TID bits */
tlb_miss_handle:
/* This may result in nested tlb miss. */
bl pte_lookup /* returns PTE address in R25 */
cmpwi %r25, 0 /* pte found? */
beq search_failed
/* Finish up, write TLB entry. */
bl tlb_fill_entry
tlb_miss_return:
TLB_UNLOCK
TLB_RESTORE
rfi
search_user_pmap:
/* Load r26 with current user space process pmap */
GET_CPUINFO(%r26)
lwz %r26, PC_CURPMAP(%r26)
b tlb_miss_handle
search_failed:
/*
* Whenever we don't find a TLB mapping in PT, set a TLB0 entry with
* the faulting virtual address anyway, but put a fake RPN and no
* access rights. This should cause a following {D,I}SI exception.
*/
lis %r23, 0xffff0000@h /* revoke all permissions */
/* Load MAS registers. */
mtspr SPR_MAS0, %r29
isync
mtspr SPR_MAS1, %r28
isync
mtspr SPR_MAS2, %r27
isync
mtspr SPR_MAS3, %r23
isync
bl zero_mas7
bl zero_mas8
tlbwe
msync
isync
b tlb_miss_return
/*****************************************************************************
*
* Return pte address that corresponds to given pmap/va. If there is no valid
* entry return 0.
*
* input: r26 - pmap
* input: r31 - dear
* output: r25 - pte address
*
* scratch regs used: r21
*
****************************************************************************/
pte_lookup:
cmpwi %r26, 0
beq 1f /* fail quickly if pmap is invalid */
srwi %r21, %r31, PDIR_SHIFT /* pdir offset */
slwi %r21, %r21, PDIR_ENTRY_SHIFT /* multiply by pdir entry size */
addi %r25, %r26, PM_PDIR /* pmap pm_dir[] address */
add %r25, %r25, %r21 /* offset within pm_pdir[] table */
/*
* Get ptbl address, i.e. pmap->pm_pdir[pdir_idx]
* This load may cause a Data TLB miss for non-kernel pmap!
*/
lwz %r25, 0(%r25)
cmpwi %r25, 0
beq 2f
lis %r21, PTBL_MASK@h
ori %r21, %r21, PTBL_MASK@l
and %r21, %r21, %r31
/* ptbl offset, multiply by ptbl entry size */
srwi %r21, %r21, (PTBL_SHIFT - PTBL_ENTRY_SHIFT)
add %r25, %r25, %r21 /* address of pte entry */
/*
* Get pte->flags
* This load may cause a Data TLB miss for non-kernel pmap!
*/
lwz %r21, PTE_FLAGS(%r25)
andi. %r21, %r21, PTE_VALID@l
bne 2f
1:
li %r25, 0
2:
blr
/*****************************************************************************
*
* Load MAS1-MAS3 registers with data, write TLB entry
*
* input:
* r29 - mas0
* r28 - mas1
* r27 - mas2
* r25 - pte
*
* output: none
*
* scratch regs: r21-r23
*
****************************************************************************/
tlb_fill_entry:
/*
* Update PTE flags: we have to do it atomically, as pmap_protect()
* running on other CPUs could attempt to update the flags at the same
* time.
*/
li %r23, PTE_FLAGS
1:
lwarx %r21, %r23, %r25 /* get pte->flags */
oris %r21, %r21, PTE_REFERENCED@h /* set referenced bit */
andi. %r22, %r21, (PTE_SW | PTE_UW)@l /* check if writable */
beq 2f
ori %r21, %r21, PTE_MODIFIED@l /* set modified bit */
2:
stwcx. %r21, %r23, %r25 /* write it back */
bne- 1b
/* Update MAS2. */
rlwimi %r27, %r21, 13, 27, 30 /* insert WIMG bits from pte */
/* Setup MAS3 value in r23. */
lwz %r23, PTE_RPN(%r25) /* get pte->rpn */
rlwinm %r22, %r23, 20, 0, 11 /* extract MAS3 portion of RPN */
rlwimi %r22, %r21, 30, 26, 31 /* insert protection bits from pte */
rlwimi %r22, %r21, 20, 12, 19 /* insert lower 8 RPN bits to MAS3 */
rlwinm %r23, %r23, 20, 24, 31 /* MAS7 portion of RPN */
/* Load MAS registers. */
mtspr SPR_MAS0, %r29
isync
mtspr SPR_MAS1, %r28
isync
mtspr SPR_MAS2, %r27
isync
mtspr SPR_MAS3, %r22
isync
mtspr SPR_MAS7, %r23
isync
mflr %r21
bl zero_mas8
mtlr %r21
tlbwe
isync
msync
blr
/*****************************************************************************
* Instruction TLB miss interrupt
*
* Same notes as for the Data TLB miss
****************************************************************************/
INTERRUPT(int_inst_tlb_error)
TLB_PROLOG
TLB_LOCK
mfsrr0 %r31 /* faulting address */
/*
* Save MAS0-MAS2 registers. There might be another tlb miss during pte
* lookup overwriting current contents (which was hw filled).
*/
mfspr %r29, SPR_MAS0
mfspr %r28, SPR_MAS1
mfspr %r27, SPR_MAS2
mfsrr1 %r21
mtcr %r21
/* check MSR[PR] */
bt 17, search_user_pmap
b search_kernel_pmap
.globl interrupt_vector_top
interrupt_vector_top:
/*****************************************************************************
* Debug interrupt
****************************************************************************/
INTERRUPT(int_debug)
STANDARD_CRIT_PROLOG(SPR_SPRG2, PC_BOOKE_CRITSAVE, SPR_CSRR0, SPR_CSRR1)
FRAME_SETUP(SPR_SPRG2, PC_BOOKE_CRITSAVE, EXC_DEBUG)
GET_CPUINFO(%r3)
lwz %r3, (PC_BOOKE_CRITSAVE+CPUSAVE_SRR0)(%r3)
bl 0f
.long interrupt_vector_base-.
.long interrupt_vector_top-.
0: mflr %r5
lwz %r4,0(%r5) /* interrupt_vector_base in r4 */
add %r4,%r4,%r5
cmplw cr0, %r3, %r4
blt 1f
lwz %r4,4(%r5) /* interrupt_vector_top in r4 */
add %r4,%r4,%r5
addi %r4,%r4,4
cmplw cr0, %r3, %r4
bge 1f
/* Disable single-stepping for the interrupt handlers. */
lwz %r3, FRAME_SRR1+8(%r1);
rlwinm %r3, %r3, 0, 23, 21
stw %r3, FRAME_SRR1+8(%r1);
/* Restore srr0 and srr1 as they could have been clobbered. */
GET_CPUINFO(%r4)
lwz %r3, (PC_BOOKE_CRITSAVE+CPUSAVE_SRR0+8)(%r4);
mtspr SPR_SRR0, %r3
lwz %r4, (PC_BOOKE_CRITSAVE+CPUSAVE_SRR1+8)(%r4);
mtspr SPR_SRR1, %r4
b 9f
1:
addi %r3, %r1, 8
bl CNAME(trap)
/*
* Handle ASTs, needed for proper support of single-stepping.
* We actually need to return to the process with an rfi.
*/
b trapexit
9:
FRAME_LEAVE(SPR_CSRR0, SPR_CSRR1)
rfci
/*****************************************************************************
* Common trap code
****************************************************************************/
trap_common:
/* Call C trap dispatcher */
addi %r3, %r1, 8
bl CNAME(trap)
.globl CNAME(trapexit) /* exported for db_backtrace use */
CNAME(trapexit):
/* disable interrupts */
wrteei 0
/* Test AST pending - makes sense for user process only */
lwz %r5, FRAME_SRR1+8(%r1)
mtcr %r5
bf 17, 1f
GET_CPUINFO(%r3)
lwz %r4, PC_CURTHREAD(%r3)
lwz %r4, TD_FLAGS(%r4)
lis %r5, (TDF_ASTPENDING | TDF_NEEDRESCHED)@h
ori %r5, %r5, (TDF_ASTPENDING | TDF_NEEDRESCHED)@l
and. %r4, %r4, %r5
beq 1f
/* re-enable interrupts before calling ast() */
wrteei 1
addi %r3, %r1, 8
bl CNAME(ast)
.globl CNAME(asttrapexit) /* db_backtrace code sentinel #2 */
CNAME(asttrapexit):
b trapexit /* test ast ret value ? */
1:
FRAME_LEAVE(SPR_SRR0, SPR_SRR1)
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 %r30, (PC_DBSAVE+CPUSAVE_R30)(%r3)
stw %r31, (PC_DBSAVE+CPUSAVE_R31)(%r3)
mflr %r31
mtsrr0 %r31
mfdear %r30
mfesr %r31
stw %r30, (PC_DBSAVE+CPUSAVE_BOOKE_DEAR)(%r3)
stw %r31, (PC_DBSAVE+CPUSAVE_BOOKE_ESR)(%r3)
mfsrr0 %r30
mfsrr1 %r31
stw %r30, (PC_DBSAVE+CPUSAVE_SRR0)(%r3)
stw %r31, (PC_DBSAVE+CPUSAVE_SRR1)(%r3)
isync
mfcr %r30
/*
* Now the kdb trap catching code.
*/
dbtrap:
FRAME_SETUP(SPR_SPRG1, PC_DBSAVE, EXC_DEBUG)
/* 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: */
b trap_common
dbleave:
FRAME_LEAVE(SPR_SRR0, SPR_SRR1)
rfi
#endif /* KDB */
clear_we:
lwz %r3, (FRAME_SRR1+8)(%r1)
rlwinm %r3, %r3, 0, 14, 12
stw %r3, (FRAME_SRR1+8)(%r1)
b trapexit
#ifdef SMP
ENTRY(tlb_lock)
GET_CPUINFO(%r5)
lwz %r5, PC_CURTHREAD(%r5)
1: lwarx %r4, 0, %r3
cmpwi %r4, TLB_UNLOCKED
bne 1b
stwcx. %r5, 0, %r3
bne- 1b
isync
msync
blr
ENTRY(tlb_unlock)
isync
msync
li %r4, TLB_UNLOCKED
stw %r4, 0(%r3)
isync
msync
blr
/*
* TLB miss spin locks. For each CPU we have a reservation granule (32 bytes);
* only a single word from this granule will actually be used as a spin lock
* for mutual exclusion between TLB miss handler and pmap layer that
* manipulates page table contents.
*/
.data
.align 5
GLOBAL(tlb0_miss_locks)
.space RES_GRANULE * MAXCPU
#endif
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