NetBSD-5.0.2/sys/arch/sh3/sh3/exception_vector.S
/* $NetBSD: exception_vector.S,v 1.42 2008/06/08 23:45:33 uwe Exp $ */
/*-
* Copyright (c) 2002 The NetBSD Foundation, 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.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``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 FOUNDATION OR CONTRIBUTORS
* 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.
*/
#include "opt_cputype.h"
#include "opt_ddb.h"
#include "assym.h"
#include <sh3/param.h>
#include <sh3/locore.h>
#include <sh3/exception.h>
#include <sh3/ubcreg.h>
#include <sh3/pte.h>
#include <sh3/mmu_sh3.h>
#include <sh3/mmu_sh4.h>
/*
* Align vectors more strictly here (where we don't really care) so
* that .align 5 (i.e. 32B cache line) before data block does the
* right thing w.r.t. final destinations after vectors are copied.
*/
#define _ALIGN_TEXT .align 5
#include <sh3/asm.h>
__KERNEL_RCSID(0, "$NetBSD: exception_vector.S,v 1.42 2008/06/08 23:45:33 uwe Exp $")
/*
* Exception vectors.
* The following routines are copied to vector addresses.
* sh_vector_generic: VBR + 0x100
* sh_vector_tlbmiss: VBR + 0x400
* sh_vector_interrupt: VBR + 0x600
*/
#define VECTOR_END_MARKER(sym) \
.globl _C_LABEL(sym); \
_C_LABEL(sym):
/*
* LINTSTUB: Var: char sh_vector_generic[1];
*
* void sh_vector_generic(void);
* Copied to VBR+0x100. This code should be position independent
* and maximum 786 bytes long (== 0x400 - 0x100).
*/
NENTRY(sh_vector_generic)
__EXCEPTION_ENTRY
__INTR_MASK(r0, r1)
/* Identify exception cause */
MOV (EXPEVT, r0)
mov.l @r0, r0
mov.l r0, @(TF_EXPEVT, r14) /* tf->tf_expevt = EXPEVT */
/* Get curlwp */
mov.l .Lg_curlwp, r1
mov.l @r1, r4 /* 1st arg */
/* Get TEA */
MOV (TEA, r1)
mov.l @r1, r6 /* 3rd arg */
/* Check TLB exception or not */
mov.l .Lg_TLB_PROT_ST, r1
cmp/hi r1, r0
bt 1f
/* tlb_exception(curlwp, tf, TEA); */
__EXCEPTION_UNBLOCK(r0, r1)
mov.l .Lg_tlb_exception, r0
jsr @r0
mov r14, r5 /* 2nd arg */
bra .Lg_return_from_exception
nop
/* general_exception(curlwp, tf, TEA); */
1: mov r4, r8
#ifdef DDB
mov #0, r2
MOV (BBRA, r1)
mov.w r2, @r1 /* disable UBC */
mov.l r2, @(TF_UBC, r14) /* clear tf->tf_ubc */
#endif /* DDB */
__EXCEPTION_UNBLOCK(r0, r1)
mov.l .Lg_general_exception, r0
jsr @r0
mov r14, r5 /* 2nd arg */
/* Check for ASTs on exit to user mode. */
mov r8, r4
mov.l .Lg_ast, r0
jsr @r0
mov r14, r5
#ifdef DDB
mov.l @(TF_UBC, r14), r2
tst r2, r2 ! ddb single-step == 0?
bt .Lg_return_from_exception
!! We are returning from DDB to do single step. Channel A in
!! UBC is already rigged, we just need to enable it.
MOV (BBRA, r3)
MOV (BARA, r5)
__EXCEPTION_BLOCK(r0, r1)
mov.l @(TF_SPC, r14), r4
mov.l r4, @r5 ! BARA = tf->tf_spc
mov.w r2, @r3 ! BBRA = tf->tf_ubc
#endif /* DDB */
.Lg_return_from_exception:
__EXCEPTION_RETURN
.align 5
REG_SYMBOL(EXPEVT)
.Lg_curlwp: .long _C_LABEL(curlwp)
REG_SYMBOL(TEA)
.Lg_TLB_PROT_ST: .long EXPEVT_TLB_PROT_ST
.Lg_tlb_exception: .long _C_LABEL(tlb_exception)
.Lg_general_exception: .long _C_LABEL(general_exception)
.Lg_ast: .long _C_LABEL(ast)
REG_SYMBOL(BBRA)
REG_SYMBOL(BARA)
/* LINTSTUB: Var: char sh_vector_generic_end[1]; */
VECTOR_END_MARKER(sh_vector_generic_end)
SET_ENTRY_SIZE(sh_vector_generic)
#ifdef SH3
/*
* LINTSTUB: Var: char sh3_vector_tlbmiss[1];
*
* TLB miss vector. We run through the fast path first, checking if
* there's a valid mapping in curlwp or kernel pmap. We do fast path
* with exceptions disabled, so no P3 addresses please (including no
* kernel stack, as we cannot wire TLB entries on sh3). We can only
* use BANK1 registers, and of those r6 and r7 are already taken.
*
* If we don't find a valid mapping in the fast path, we do context
* save and call tlb exception handler.
*
* Copied to VBR+0x400. This code should be position independent
* and maximum 512 bytes long (== 0x600 - 0x400).
*/
NENTRY(sh3_vector_tlbmiss)
mov #(SH3_PTEH & 0xff), r4
mov.l .L3_VPN_cleanup, r0
mov.l @r4, r5
and r0, r5 ! trim vpn to 4K page boundary
!! For the duration of fast path we keep
!! r4: SH3_PTEH - other PTE regs are addressable as @(offset, r4)
!! r5: { VPN, ASID } that caused the miss
cmp/pz r5 ! user space address?
bt/s .L3_user_va
mov r5, r2 ! copy of vpn to compute indices into ptd/ptp
!! kernel space address, use pmap_kernel(), adjust vpn for indexing
!! see __pmap_kpte_lookup
.L3_kernel_va:
mov.l .L3_VM_MIN_KERNEL_ADDRESS, r0
mov.l .L3_kernptd, r1 ! pmap_kernel()->pm_ptp
bra .L3_fetch_pte
sub r0, r2 ! vpn -= VM_MIN_KERNEL_ADDRESS
!! user space address, use curlwp's pmap
.L3_user_va:
mov.l .L3_curptd, r1 ! curlwp->...->pm_ptp
!! see __pmap_pte_lookup
.L3_fetch_pte:
mov.l @r1, r3 ! fetch ptd
!! r2: vpn, prepared for indexing into ptd
!! r3: pt_entry_t **ptd => pt_entry_t *ptp => pt_entry_t pte
#ifdef DEBUG
tst r3, r3 ! ptd == NULL - cannot happen
bt/s .L3_call_tlb_exception
#endif
mov #-22, r1 ! __PMAP_PTP_SHIFT
!! __PMAP_PTP_INDEX(vpn)
mov r2, r0
shld r1, r0 ! vpn >> __PMAP_PTP_SHIFT
mov.l .L3_ptp_index_mask, r1
and r1, r0 ! ... & (__PMAP_PTP_N - 1)
shll2 r0 ! array index -> array offset
mov.l @(r0, r3), r3 ! ptp = ptd[idx]
tst r3, r3 ! if (ptp == NULL)
bt/s .L3_call_tlb_exception
mov #-(PGSHIFT - 2), r1
!! __PMAP_PTP_OFSET(vpn) - except we pre-shift 2 bits left to
!! get the array offset directly, as we know bits 10 and 11
!! are zero (we cleaned them in r5 to get 4K aligned VPN)
shld r1, r2 ! vpn >> (PGSHIFT - 2)
mov.l .L3_ptp_offset_mask, r0
and r2, r0 ! ... & ((__PMAP_PTP_PG_N - 1) << 2)
mov.l @(r0, r3), r3 ! pte = ptp[idx]
!! r3: pte
!! r4: SH3_PTEH
!! r5: { VPN, ASID }
mov.l .L3_PG_V, r0
tst r0, r3 ! if ((pte & PG_V) == 0)
bt/s .L3_call_tlb_exception
nop
mov.l .L3_PG_HW_BITS, r1
cmp/pz r5 ! user space address?
and r1, r3 ! pte &= PG_HW_BITS
bf/s .L3_load_kernel
mov.l r3, @(0x04, r4) ! *SH3_PTEL = pte
!! load mapping for a user space page
!! we reload PTEH to enter VPN aligned to 4K page boundary
.L3_load_user:
mov.l r5, @r4 ! *SH3_PTEH = { VPN, ASID }
ldtlb ! needs 2 insns padding before RTE
nop
nop
rte
nop
!! load mapping for a kernel space page
!! we need to temporary set ASID to 0
.L3_load_kernel:
mov.l .L3_clear_ASID, r1
and r5, r1 ! *SH3_PTEH & ~SH3_PTEH_ASID_MASK
mov.l r1, @r4 ! *SH3_PTEH = { VPN, ASID = 0 }
ldtlb
mov.l r5, @r4 ! restore ASID
nop
rte
nop
!! if we haven't found a valid mapping in the fast path
!! tlb_exception(curlwp, trapframe, tea)
.L3_call_tlb_exception:
__EXCEPTION_ENTRY
mov.l .L3_SH3_EXPEVT, r2
mov.l .L3_curlwp, r1
mov #(SH3_TEA & 0xff), r0
mov.l @r2, r2 ! *SH3_EXPEVT
mov.l @r0, r6 ! arg3: va = *SH3_TEA
mov.l @r1, r4 ! arg1: curlwp
__INTR_MASK(r0, r1)
__EXCEPTION_UNBLOCK(r0, r1)
mov.l .L3_tlb_exception, r0
mov.l r2, @(TF_EXPEVT, r14) ! tf->tf_expevt = EXPEVT
jsr @r0
mov r14, r5 ! arg2: trapframe
__EXCEPTION_RETURN
.align 4
.L3_VPN_cleanup: .long ~0x00000c00
.L3_curptd: .long _C_LABEL(curptd)
.L3_kernptd: .long _C_LABEL(__pmap_kernel)
.L3_VM_MIN_KERNEL_ADDRESS: .long VM_MIN_KERNEL_ADDRESS
.L3_ptp_index_mask: .long 0x1ff
.L3_ptp_offset_mask: .long 0x3ff << 2
.L3_PG_HW_BITS: .long PG_HW_BITS
.L3_PG_V: .long PG_V
.L3_clear_ASID: .long ~SH3_PTEH_ASID_MASK
.L3_SH3_EXPEVT: .long SH3_EXPEVT
.L3_curlwp: .long _C_LABEL(curlwp)
.L3_tlb_exception: .long _C_LABEL(tlb_exception)
/* LINTSTUB: Var: char sh3_vector_tlbmiss_end[1]; */
VECTOR_END_MARKER(sh3_vector_tlbmiss_end)
SET_ENTRY_SIZE(sh3_vector_tlbmiss)
#endif /* SH3 */
#ifdef SH4
/*
* LINTSTUB: Var: char sh4_vector_tlbmiss[1];
*
* TLB miss vector. We run through the fast path first, checking if
* there's a valid mapping in curlwp or kernel pmap. We do fast path
* with exceptions disabled, so no P3 addresses please (though we can
* use kernel stack if need be, as its TLB entries are wired). We can
* only use BANK1 registers, and of those r6 and r7 are already taken.
*
* If we don't find a valid mapping in the fast path, we do context
* save and call tlb exception handler.
*
* Copied to VBR+0x400. This code should be relocatable
* and maximum 512 bytes long (== 0x600 - 0x400).
*/
NENTRY(sh4_vector_tlbmiss)
mov.l .L4_SH4_PTEH, r4
mov.l .L4_VPN_cleanup, r0
mov.l @r4, r5
and r0, r5 ! trim vpn to 4K page boundary
!! For the duration of fast path we keep
!! r4: SH4_PTEH - other PTE regs are addressable as @(offset, r4)
!! r5: { VPN, ASID } that caused the miss
cmp/pz r5 ! user space address?
bt/s .L4_user_va
mov r5, r2 ! copy of vpn to compute indices into ptd/ptp
!! kernel space address, use pmap_kernel(), adjust vpn for indexing
!! see __pmap_kpte_lookup
.L4_kernel_va:
mov.l .L4_VM_MIN_KERNEL_ADDRESS, r0
mov.l .L4_kernptd, r1 ! pmap_kernel()->pm_ptp
bra .L4_fetch_pte
sub r0, r2 ! vpn -= VM_MIN_KERNEL_ADDRESS
!! user space address, use curlwp's pmap
.L4_user_va:
mov.l .L4_curptd, r1 ! curlwp->...->pm_ptp
!! see __pmap_pte_lookup
.L4_fetch_pte:
mov.l @r1, r3 ! fetch ptd
!! r2: vpn, prepared for indexing into ptd
!! r3: pt_entry_t **ptd => pt_entry_t *ptp => pt_entry_t pte
#ifdef DEBUG
tst r3, r3 ! ptd == NULL - cannot happen
bt/s .L4_call_tlb_exception
#endif
mov #-22, r1 ! __PMAP_PTP_SHIFT
!! __PMAP_PTP_INDEX(vpn)
mov r2, r0
shld r1, r0 ! vpn >> __PMAP_PTP_SHIFT
mov.l .L4_ptp_index_mask, r1
and r1, r0 ! ... & (__PMAP_PTP_N - 1)
shll2 r0 ! array index -> array offset
mov.l @(r0, r3), r3 ! ptp = ptd[idx]
tst r3, r3 ! if (ptp == NULL)
bt/s .L4_call_tlb_exception
mov #-(PGSHIFT - 2), r1
!! __PMAP_PTP_OFSET(vpn) - except we pre-shift 2 bits left to
!! get the array offset directly, as we know bits 10 and 11
!! are zero (we cleaned them in r5 to get 4K aligned VPN)
shld r1, r2 ! vpn >> (PGSHIFT - 2)
mov.l .L4_ptp_offset_mask, r0
and r2, r0 ! ... & ((__PMAP_PTP_PG_N - 1) << 2)
mov.l @(r0, r3), r3 ! pte = ptp[idx]
!! r3: pte
!! r4: SH4_PTEH
!! r5: { VPN, ASID }
mov.l .L4_PG_V, r0
tst r0, r3 ! if ((pte & PG_V) == 0)
bt/s .L4_call_tlb_exception
mov r3, r0 ! prepare PCMCIA SA bits for SH4_PTEA
mov.l .L4_PG_HW_BITS, r1
shlr8 r0
and r1, r3 ! pte &= PG_HW_BITS
shlr r0 ! pte >> _PG_PCMCIA_SHIFT
cmp/pz r5 ! user space address?
and #SH4_PTEA_SA_MASK, r0
mov.l r3, @(0x04, r4) ! *SH4_PTEL = pte
bf/s .L4_load_kernel
mov.l r0, @(0x34, r4) ! *SH4_PTEA = PCMCIA space attrs
!! load mapping for a user space page
!! we reload PTEH to enter VPN aligned to 4K page boundary
.L4_load_user:
mov.l r5, @r4 ! *SH4_PTEH = { VPN, ASID }
ldtlb ! needs 1 insn padding before RTE
nop
rte
nop
!! load mapping for a kernel space page
!! we need to temporary set ASID to 0
.L4_load_kernel:
mov.l .L4_clear_ASID, r1
and r5, r1 ! *SH4_PTEH & ~SH4_PTEH_ASID_MASK
mov.l r1, @r4 ! *SH4_PTEH = { VPN, ASID = 0 }
ldtlb
mov.l r5, @r4 ! restore ASID
rte
nop
!! if we haven't found a valid mapping in the fast path
!! tlb_exception(curlwp, trapframe, tea)
.L4_call_tlb_exception:
__EXCEPTION_ENTRY
mov.l .L4_SH4_PTEH, r0
mov.l .L4_curlwp, r1
mov.l @(0x24, r0), r2 ! *SH4_EXPEVT
mov.l @(0x0c, r0), r6 ! arg3: va = *SH4_TEA
mov.l @r1, r4 ! arg1: curlwp
__INTR_MASK(r0, r1)
__EXCEPTION_UNBLOCK(r0, r1)
mov.l .L4_tlb_exception, r0
mov.l r2, @(TF_EXPEVT, r14) ! tf->tf_expevt = EXPEVT
jsr @r0
mov r14, r5 ! arg2: trapframe
__EXCEPTION_RETURN
.align 5
.L4_SH4_PTEH: .long SH4_PTEH
.L4_VPN_cleanup: .long ~0x00000c00
.L4_curptd: .long _C_LABEL(curptd)
.L4_kernptd: .long _C_LABEL(__pmap_kernel)
.L4_VM_MIN_KERNEL_ADDRESS: .long VM_MIN_KERNEL_ADDRESS
.L4_ptp_index_mask: .long 0x1ff
.L4_ptp_offset_mask: .long 0x3ff << 2
.L4_PG_HW_BITS: .long PG_HW_BITS
.L4_PG_V: .long PG_V
.L4_clear_ASID: .long ~SH4_PTEH_ASID_MASK
.L4_curlwp: .long _C_LABEL(curlwp)
.L4_tlb_exception: .long _C_LABEL(tlb_exception)
/* LINTSTUB: Var: char sh4_vector_tlbmiss_end[1]; */
VECTOR_END_MARKER(sh4_vector_tlbmiss_end)
SET_ENTRY_SIZE(sh4_vector_tlbmiss)
#endif /* SH4 */
/*
* LINTSTUB: Var: char sh_vector_interrupt[1];
*
* void sh_vector_interrupt(void);
* Copied to VBR+0x600. This code should be position independent.
*/
NENTRY(sh_vector_interrupt)
__EXCEPTION_ENTRY
stc r0_bank, r6 ! ssp - 3rd arg to intc_intr()
__INTR_MASK(r0, r1)
__EXCEPTION_UNBLOCK(r0, r1) ! enable exceptions for P3 access
mov.l .Li_ci_idepth, r8 ! callee-saved
mov.l .Li_uvmexp_intrs, r2
mov.l .Li_intc_intr, r0
mov.l @r8, r9 ! callee-saved
mov #0, r1
mov.l @r2, r3
add #1, r9 ! curcpu()->ci_idepth++
mov.l r1, @(TF_EXPEVT, r14) ! tf->tf_expevt = 0 (for debug)?
add #1, r3 ! ++uvmexp.intrs
mov.l r9, @r8
jsr @r0 ! intc_intr(ssr, spc, ssp)
mov.l r3, @r2
cmp/pl r9 ! curcpu()->ci_idepth > 0
add #-1, r9 ! curcpu()->ci_idepth--
bt/s .Li_return_to_kernel ! returning from a nested interrupt
mov.l r9, @r8
mov.l @(TF_SSR, r14), r2
mov.l .Li_PSL_MD, r1
tst r1, r2 ! tf->tf_ssr & PSL_MD == 0 ?
bt .Li_return_to_user
.Li_return_to_kernel:
!! Check for interrupted kernel RAS when returning to kernel
mov.l @(TF_SPC, r14), r2
mov.l .Li_ras_start, r3
cmp/hi r3, r2 ! spc > _lock_cas_ras_start ?
bf .Li_return_from_interrupt
mov.l .Li_ras_end, r1
cmp/hs r1, r2 ! spc >= _lock_cas_ras_end ?
bt .Li_return_from_interrupt
bra .Li_return_from_interrupt
mov.l r3, @(TF_SPC, r14) ! spc = _lock_cas_ras_start
.Li_return_to_user:
/* Check for ASTs on exit to user mode. */
mov.l .Li_ast, r0
mov.l .Li_curlwp, r1
mov r14, r5 /* 2nd arg */
jsr @r0
mov.l @r1, r4 /* 1st arg */
.Li_return_from_interrupt:
__EXCEPTION_RETURN
.align 5
.Li_ci_idepth: .long _C_LABEL(cpu_info_store) + CI_IDEPTH
.Li_uvmexp_intrs: .long _C_LABEL(uvmexp) + UVMEXP_INTRS
.Li_intc_intr: .long _C_LABEL(intc_intr)
.Li_PSL_MD: .long 0x40000000 /* PSL_MD */
.Li_ras_start: .long _C_LABEL(_lock_cas_ras_start)
.Li_ras_end: .long _C_LABEL(_lock_cas_ras_end)
.Li_ast: .long _C_LABEL(ast)
.Li_curlwp: .long _C_LABEL(curlwp)
/* LINTSTUB: Var: char sh_vector_interrupt_end[1]; */
VECTOR_END_MARKER(sh_vector_interrupt_end)
SET_ENTRY_SIZE(sh_vector_interrupt)