#////////////////////////////////////////////////////////////////////////////////
#// exceptions.S - Exception handlers for sio shell
#// Written by TyRaNiD (c) 2005
#// Much props to Herben und Pixel
#////////////////////////////////////////////////////////////////////////////////
#include "r5900_regs.h"
.text
.p2align 3
.set push
.set noreorder
.set noat
.global _level2SavedRegs
.global _level2ExceptionStack
.global level2ExceptionHandler
.ent level2ExceptionHandler
level2ExceptionHandler:
sq k0, -0x20($0)
la k0, _level2SavedRegs
#lui k1, 0x8000
# or k0, k0, k1
sq $0, 0x00(k0)
sq $1, 0x10(k0)
sq $2, 0x20(k0)
sq $3, 0x30(k0)
sq $4, 0x40(k0)
sq $5, 0x50(k0)
sq $6, 0x60(k0)
sq $7, 0x70(k0)
sq $8, 0x80(k0)
sq $9, 0x90(k0)
sq $10, 0xa0(k0)
sq $11, 0xb0(k0)
sq $12, 0xc0(k0)
sq $13, 0xd0(k0)
sq $14, 0xe0(k0)
sq $15, 0xf0(k0)
sq $16, 0x100(k0)
sq $17, 0x110(k0)
sq $18, 0x120(k0)
sq $19, 0x130(k0)
sq $20, 0x140(k0)
sq $21, 0x150(k0)
sq $22, 0x160(k0)
sq $23, 0x170(k0)
sq $24, 0x180(k0)
sq $25, 0x190(k0)
# Restore k0 and save
lq $1, -0x20($0)
sq $1, 0x1a0(k0) # zero instead of k0
sq $27, 0x1b0(k0) # $k1
sq $28, 0x1c0(k0)
sq $29, 0x1d0(k0) # sp
sq $30, 0x1e0(k0)
sq $31, 0x1f0(k0) # $ra
pmfhi t0 # HI
pmflo t1 # LO
sq t0, 0x200(k0)
sq t1, 0x210(k0)
mfc0 t0, BadVAddr # Cop0 state regs
mfc0 t1, Status
sw t0, 0x220(k0)
sw t1, 0x224(k0)
mfc0 t0, Cause
mfc0 t1, EPC
sw t0, 0x228(k0)
sw t1, 0x22c(k0)
# Kernel saves these two also..
mfc0 t0, ErrorPC
mfc0 t1, PerfCnt
sw t0, 0x230(k0)
sw t1, 0x234(k0)
mfsa t0
sw t0, 0x238(k0)
# Use our own stack..
la sp, _level2ExceptionStack+0x2800-16
la gp, _gp # Use exception handlers _gp
# Return from exception and start 'debugger'
jal sio_shell_level2
nop
la k0, _level2SavedRegs
lq t0, 0x200(k0)
lq t1, 0x210(k0)
pmthi t0 # HI
pmtlo t1 # LO
lw t0, 0x220(k0)
lw t1, 0x224(k0)
mtc0 t0, BadVAddr
mtc0 t1, Status
lw t0, 0x228(k0)
lw t1, 0x22c(k0)
mtc0 t0, Cause
mtc0 t1, EPC
# Kernel saves these two also..
lw t0, 0x230(k0)
lw t1, 0x234(k0)
mtc0 t0, ErrorPC
mtc0 t1, PerfCnt
# Shift Amount reg
lw t0, 0x238(k0)
mtsa t0
lq $0, 0x00(k0)
lq $1, 0x10(k0)
lq $2, 0x20(k0)
lq $3, 0x30(k0)
lq $4, 0x40(k0)
lq $5, 0x50(k0)
lq $6, 0x60(k0)
lq $7, 0x70(k0)
lq $8, 0x80(k0)
lq $9, 0x90(k0)
lq $10, 0xa0(k0)
lq $11, 0xb0(k0)
lq $12, 0xc0(k0)
lq $13, 0xd0(k0)
lq $14, 0xe0(k0)
lq $15, 0xf0(k0)
lq $16, 0x100(k0)
lq $17, 0x110(k0)
lq $18, 0x120(k0)
lq $19, 0x130(k0)
lq $20, 0x140(k0)
lq $21, 0x150(k0)
lq $22, 0x160(k0)
lq $23, 0x170(k0)
lq $24, 0x180(k0)
lq $25, 0x190(k0)
# no k0
lq $27, 0x1b0(k0) # $k1
lq $28, 0x1c0(k0)
lq $29, 0x1d0(k0) # sp
lq $30, 0x1e0(k0)
lq $31, 0x1f0(k0) # $ra
lq k0, -0x20($0)
sync
eret
nop
.end level2ExceptionHandler
.global _level1SavedRegs
.global _level1ExceptionStack
.global level1ExceptionHandler
.ent level1ExceptionHandler
level1ExceptionHandler:
# Kernel doesn't save k0 anyway so why should we bother (it is already trashed)
la k0, _level1SavedRegs
sq $0, 0x00(k0)
sq $1, 0x10(k0)
sq $2, 0x20(k0)
sq $3, 0x30(k0)
sq $4, 0x40(k0)
sq $5, 0x50(k0)
sq $6, 0x60(k0)
sq $7, 0x70(k0)
sq $8, 0x80(k0)
sq $9, 0x90(k0)
sq $10, 0xa0(k0)
sq $11, 0xb0(k0)
sq $12, 0xc0(k0)
sq $13, 0xd0(k0)
sq $14, 0xe0(k0)
sq $15, 0xf0(k0)
sq $16, 0x100(k0)
sq $17, 0x110(k0)
sq $18, 0x120(k0)
sq $19, 0x130(k0)
sq $20, 0x140(k0)
sq $21, 0x150(k0)
sq $22, 0x160(k0)
sq $23, 0x170(k0)
sq $24, 0x180(k0)
sq $25, 0x190(k0)
# Restore k0 and save
sq $0, 0x1a0(k0) # zero instead of k0
sq $27, 0x1b0(k0) # $k1
sq $28, 0x1c0(k0)
sq $29, 0x1d0(k0) # sp
sq $30, 0x1e0(k0)
sq $31, 0x1f0(k0) # $ra
pmfhi t0 # HI
pmflo t1 # LO
sq t0, 0x200(k0)
sq t1, 0x210(k0)
mfc0 t0, BadVAddr # Cop0 state regs
mfc0 t1, Status
sw t0, 0x220(k0)
sw t1, 0x224(k0)
mfc0 t0, Cause
mfc0 t1, EPC
sw t0, 0x228(k0)
sw t1, 0x22c(k0)
# Kernel saves these two also..
mfc0 t0, ErrorPC
mfc0 t1, PerfCnt
sw t0, 0x230(k0)
sw t1, 0x234(k0)
mfsa t0
sw t0, 0x238(k0)
# Use our own stack..
la sp, _level1ExceptionStack+0x2800-16
la gp, _gp # Use exception handlers _gp
# Return from exception and start 'debugger'
jal sio_shell_level1
nop
la k0, _level1SavedRegs
lq t0, 0x200(k0)
lq t1, 0x210(k0)
pmthi t0 # HI
pmtlo t1 # LO
lw t0, 0x220(k0)
lw t1, 0x224(k0)
mtc0 t0, BadVAddr
mtc0 t1, Status
lw t0, 0x228(k0)
lw t1, 0x22c(k0)
mtc0 t0, Cause
mtc0 t1, EPC
# Kernel saves these two also..
lw t0, 0x230(k0)
lw t1, 0x234(k0)
mtc0 t0, ErrorPC
mtc0 t1, PerfCnt
# Shift Amount reg
lw t0, 0x238(k0)
mtsa t0
lq $0, 0x00(k0)
lq $1, 0x10(k0)
lq $2, 0x20(k0)
lq $3, 0x30(k0)
lq $4, 0x40(k0)
lq $5, 0x50(k0)
lq $6, 0x60(k0)
lq $7, 0x70(k0)
lq $8, 0x80(k0)
lq $9, 0x90(k0)
lq $10, 0xa0(k0)
lq $11, 0xb0(k0)
lq $12, 0xc0(k0)
lq $13, 0xd0(k0)
lq $14, 0xe0(k0)
lq $15, 0xf0(k0)
lq $16, 0x100(k0)
lq $17, 0x110(k0)
lq $18, 0x120(k0)
lq $19, 0x130(k0)
lq $20, 0x140(k0)
lq $21, 0x150(k0)
lq $22, 0x160(k0)
lq $23, 0x170(k0)
lq $24, 0x180(k0)
lq $25, 0x190(k0)
# no k0
lq $27, 0x1b0(k0) # $k1
lq $28, 0x1c0(k0)
lq $29, 0x1d0(k0) # sp
lq $30, 0x1e0(k0)
lq $31, 0x1f0(k0) # $ra
sync
eret
nop
.end level1ExceptionHandler
# Restore the context and jump to Syscall handler
.global restartSyscallException
.ent restartSyscallException
restartSyscallException:
la k0, _level1SavedRegs
lq t0, 0x200(k0)
lq t1, 0x210(k0)
pmthi t0 # HI
pmtlo t1 # LO
lw t0, 0x220(k0)
lw t1, 0x224(k0)
mtc0 t0, BadVAddr
mtc0 t1, Status
lw t0, 0x228(k0)
lw t1, 0x22c(k0)
mtc0 t0, Cause
mtc0 t1, EPC
# Kernel saves these two also..
lw t0, 0x230(k0)
lw t1, 0x234(k0)
mtc0 t0, ErrorPC
mtc0 t1, PerfCnt
# Shift Amount reg
lw t0, 0x238(k0)
mtsa t0
lq $0, 0x00(k0)
lq $1, 0x10(k0)
lq $2, 0x20(k0)
lq $3, 0x30(k0)
lq $4, 0x40(k0)
lq $5, 0x50(k0)
lq $6, 0x60(k0)
lq $7, 0x70(k0)
lq $8, 0x80(k0)
lq $9, 0x90(k0)
lq $10, 0xa0(k0)
lq $11, 0xb0(k0)
lq $12, 0xc0(k0)
lq $13, 0xd0(k0)
lq $14, 0xe0(k0)
lq $15, 0xf0(k0)
lq $16, 0x100(k0)
lq $17, 0x110(k0)
lq $18, 0x120(k0)
lq $19, 0x130(k0)
lq $20, 0x140(k0)
lq $21, 0x150(k0)
lq $22, 0x160(k0)
lq $23, 0x170(k0)
lq $24, 0x180(k0)
lq $25, 0x190(k0)
# no k0
lq $27, 0x1b0(k0) # $k1
lq $28, 0x1c0(k0)
lq $29, 0x1d0(k0) # sp
lq $30, 0x1e0(k0)
lq $31, 0x1f0(k0) # $ra
j 0x280
nop
.end restartSyscallException
.bss
.align 4
.ent _level2SavedRegs
_level2SavedRegs:
.space 0x240, 0
.end _level2SavedRegs
.align 4
.ent _level2ExceptionStack
_level2ExceptionStack:
.space 0x2800, 0
.end _level2ExceptionStack
.align 4
.ent _level1SavedRegs
_level1SavedRegs:
.space 0x240, 0
.end _level1SavedRegs
.align 4
.ent _level1ExceptionStack
_level1ExceptionStack:
.space 0x2800, 0
.end _level1ExceptionStack