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Ignore whitespace Rev 2606 → Rev 2607

/trunk/kernel/arch/mips32/include/stack.h
38,6 → 38,14
#define STACK_ITEM_SIZE 4
#define STACK_ALIGNMENT 8
 
#define STACK_ARG0 0
#define STACK_ARG1 4
#define STACK_ARG2 8
#define STACK_ARG3 12
#define STACK_ARG4 16
#define STACK_ARG5 20
#define STACK_ARG6 24
 
#endif
 
/** @}
/trunk/kernel/arch/mips32/src/start.S
30,6 → 30,7
#include <arch/mm/page.h>
#include <arch/asm/boot.h>
#include <arch/context_offset.h>
#include <arch/stack.h>
.text
 
51,23 → 52,23
# These changes will be automatically reversed in REGISTER_LOAD
# SP is NOT saved as part of these registers
.macro REGISTERS_STORE_AND_EXC_RESET r
sw $at,EOFFSET_AT(\r)
sw $v0,EOFFSET_V0(\r)
sw $v1,EOFFSET_V1(\r)
sw $a0,EOFFSET_A0(\r)
sw $a1,EOFFSET_A1(\r)
sw $a2,EOFFSET_A2(\r)
sw $a3,EOFFSET_A3(\r)
sw $t0,EOFFSET_T0(\r)
sw $t1,EOFFSET_T1(\r)
sw $t2,EOFFSET_T2(\r)
sw $t3,EOFFSET_T3(\r)
sw $t4,EOFFSET_T4(\r)
sw $t5,EOFFSET_T5(\r)
sw $t6,EOFFSET_T6(\r)
sw $t7,EOFFSET_T7(\r)
sw $t8,EOFFSET_T8(\r)
sw $t9,EOFFSET_T9(\r)
sw $at, EOFFSET_AT(\r)
sw $v0, EOFFSET_V0(\r)
sw $v1, EOFFSET_V1(\r)
sw $a0, EOFFSET_A0(\r)
sw $a1, EOFFSET_A1(\r)
sw $a2, EOFFSET_A2(\r)
sw $a3, EOFFSET_A3(\r)
sw $t0, EOFFSET_T0(\r)
sw $t1, EOFFSET_T1(\r)
sw $t2, EOFFSET_T2(\r)
sw $t3, EOFFSET_T3(\r)
sw $t4, EOFFSET_T4(\r)
sw $t5, EOFFSET_T5(\r)
sw $t6, EOFFSET_T6(\r)
sw $t7, EOFFSET_T7(\r)
sw $t8, EOFFSET_T8(\r)
sw $t9, EOFFSET_T9(\r)
 
mflo $at
sw $at, EOFFSET_LO(\r)
75,27 → 76,27
sw $at, EOFFSET_HI(\r)
#ifdef CONFIG_DEBUG_ALLREGS
sw $s0,EOFFSET_S0(\r)
sw $s1,EOFFSET_S1(\r)
sw $s2,EOFFSET_S2(\r)
sw $s3,EOFFSET_S3(\r)
sw $s4,EOFFSET_S4(\r)
sw $s5,EOFFSET_S5(\r)
sw $s6,EOFFSET_S6(\r)
sw $s7,EOFFSET_S7(\r)
sw $s8,EOFFSET_S8(\r)
sw $s0, EOFFSET_S0(\r)
sw $s1, EOFFSET_S1(\r)
sw $s2, EOFFSET_S2(\r)
sw $s3, EOFFSET_S3(\r)
sw $s4, EOFFSET_S4(\r)
sw $s5, EOFFSET_S5(\r)
sw $s6, EOFFSET_S6(\r)
sw $s7, EOFFSET_S7(\r)
sw $s8, EOFFSET_S8(\r)
#endif
sw $gp,EOFFSET_GP(\r)
sw $ra,EOFFSET_RA(\r)
sw $k1,EOFFSET_K1(\r)
sw $gp, EOFFSET_GP(\r)
sw $ra, EOFFSET_RA(\r)
sw $k1, EOFFSET_K1(\r)
 
mfc0 $t0, $status
mfc0 $t1, $epc
and $t2, $t0, REG_SAVE_MASK # Save only KSU,EXL,ERL,IE
and $t2, $t0, REG_SAVE_MASK # Save only KSU,EXL,ERL,IE
li $t3, ~(0x1f)
and $t0, $t0, $t3 # Clear KSU,EXL,ERL,IE
and $t0, $t0, $t3 # Clear KSU,EXL,ERL,IE
sw $t2,EOFFSET_STATUS(\r)
sw $t1,EOFFSET_EPC(\r)
108,54 → 109,54
mfc0 $t0, $status
lw $t1,EOFFSET_STATUS(\r)
 
li $t2, ~REG_SAVE_MASK # Mask UM,EXL,ERL,IE
li $t2, ~REG_SAVE_MASK # Mask UM,EXL,ERL,IE
and $t0, $t0, $t2
or $t0, $t0, $t1 # Copy UM,EXL,ERL,IE from saved status
or $t0, $t0, $t1 # Copy UM,EXL, ERL, IE from saved status
mtc0 $t0, $status
lw $v0,EOFFSET_V0(\r)
lw $v1,EOFFSET_V1(\r)
lw $a0,EOFFSET_A0(\r)
lw $a1,EOFFSET_A1(\r)
lw $a2,EOFFSET_A2(\r)
lw $a3,EOFFSET_A3(\r)
lw $t0,EOFFSET_T0(\r)
lw $t1,EOFFSET_T1(\r)
lw $t2,EOFFSET_T2(\r)
lw $t3,EOFFSET_T3(\r)
lw $t4,EOFFSET_T4(\r)
lw $t5,EOFFSET_T5(\r)
lw $t6,EOFFSET_T6(\r)
lw $t7,EOFFSET_T7(\r)
lw $t8,EOFFSET_T8(\r)
lw $t9,EOFFSET_T9(\r)
lw $v0, EOFFSET_V0(\r)
lw $v1, EOFFSET_V1(\r)
lw $a0, EOFFSET_A0(\r)
lw $a1, EOFFSET_A1(\r)
lw $a2, EOFFSET_A2(\r)
lw $a3, EOFFSET_A3(\r)
lw $t0, EOFFSET_T0(\r)
lw $t1, EOFFSET_T1(\r)
lw $t2, EOFFSET_T2(\r)
lw $t3, EOFFSET_T3(\r)
lw $t4, EOFFSET_T4(\r)
lw $t5, EOFFSET_T5(\r)
lw $t6, EOFFSET_T6(\r)
lw $t7, EOFFSET_T7(\r)
lw $t8, EOFFSET_T8(\r)
lw $t9, EOFFSET_T9(\r)
#ifdef CONFIG_DEBUG_ALLREGS
lw $s0,EOFFSET_S0(\r)
lw $s1,EOFFSET_S1(\r)
lw $s2,EOFFSET_S2(\r)
lw $s3,EOFFSET_S3(\r)
lw $s4,EOFFSET_S4(\r)
lw $s5,EOFFSET_S5(\r)
lw $s6,EOFFSET_S6(\r)
lw $s7,EOFFSET_S7(\r)
lw $s8,EOFFSET_S8(\r)
lw $s0, EOFFSET_S0(\r)
lw $s1, EOFFSET_S1(\r)
lw $s2, EOFFSET_S2(\r)
lw $s3, EOFFSET_S3(\r)
lw $s4, EOFFSET_S4(\r)
lw $s5, EOFFSET_S5(\r)
lw $s6, EOFFSET_S6(\r)
lw $s7, EOFFSET_S7(\r)
lw $s8, EOFFSET_S8(\r)
#endif
lw $gp,EOFFSET_GP(\r)
lw $ra,EOFFSET_RA(\r)
lw $k1,EOFFSET_K1(\r)
lw $gp, EOFFSET_GP(\r)
lw $ra, EOFFSET_RA(\r)
lw $k1, EOFFSET_K1(\r)
lw $at,EOFFSET_LO(\r)
lw $at, EOFFSET_LO(\r)
mtlo $at
lw $at,EOFFSET_HI(\r)
lw $at, EOFFSET_HI(\r)
mthi $at
 
lw $at,EOFFSET_EPC(\r)
lw $at, EOFFSET_EPC(\r)
mtc0 $at, $epc
lw $at,EOFFSET_AT(\r)
lw $sp,EOFFSET_SP(\r)
lw $at, EOFFSET_AT(\r)
lw $sp, EOFFSET_SP(\r)
.endm
 
# Move kernel stack pointer address to register K0
228,28 → 229,26
exception_entry:
j exception_handler
nop
 
exception_handler:
KERNEL_STACK_TO_K0
sub $k0, REGISTER_SPACE
sw $sp,EOFFSET_SP($k0)
sw $sp, EOFFSET_SP($k0)
move $sp, $k0
mfc0 $k0, $cause
sra $k0, $k0, 0x2 # cp0_exc_cause() part 1
andi $k0, $k0, 0x1f # cp0_exc_cause() part 2
sub $k0, 8 # 8=SYSCALL
sra $k0, $k0, 0x2 # cp0_exc_cause() part 1
andi $k0, $k0, 0x1f # cp0_exc_cause() part 2
sub $k0, 8 # 8 = SYSCALL
beqz $k0, syscall_shortcut
add $k0, 8 # Revert $k0 back to correct exc number
add $k0, 8 # Revert $k0 back to correct exc number
REGISTERS_STORE_AND_EXC_RESET $sp
move $a1, $sp
jal exc_dispatch # exc_dispatch(excno, register_space)
jal exc_dispatch # exc_dispatch(excno, register_space)
move $a0, $k0
 
REGISTERS_LOAD $sp
256,49 → 255,66
# The $sp is automatically restored to former value
eret
 
# it seems that mips reserves some space on stack for varfuncs???
#define SS_ARG4 16
#define SS_SP EOFFSET_SP
#define SS_STATUS EOFFSET_STATUS
#define SS_EPC EOFFSET_EPC
#define SS_K1 EOFFSET_K1
## Syscall entry
#
# Registers:
#
# @param v0 Syscall number.
# @param a0 1st argument.
# @param a1 2nd argument.
# @param a2 3rd argument.
# @param a3 4th argument.
# @param t0 5th argument.
# @param t1 6th argument.
#
# @return The return value will be stored in v0.
#
#define SS_SP EOFFSET_SP
#define SS_STATUS EOFFSET_STATUS
#define SS_EPC EOFFSET_EPC
#define SS_K1 EOFFSET_K1
syscall_shortcut:
# We have a lot of space on the stack, with free use
mfc0 $t1, $epc
mfc0 $t0, $status
sw $t1,SS_EPC($sp) # Save EPC
sw $k1,SS_K1($sp) # Save k1, which is not saved during context switch
mfc0 $t3, $epc
mfc0 $t2, $status
sw $t3, SS_EPC($sp) # Save EPC
sw $k1, SS_K1($sp) # Save k1 not saved on context switch
and $t2, $t0, REG_SAVE_MASK # Save only KSU,EXL,ERL,IE
li $t3, ~(0x1f)
and $t0, $t0, $t3 # Clear KSU,EXL,ERL
ori $t0, $t0, 0x1 # Set IE
and $t4, $t2, REG_SAVE_MASK # Save only KSU, EXL, ERL, IE
li $t5, ~(0x1f)
and $t2, $t2, $t5 # Clear KSU, EXL, ERL
ori $t2, $t2, 0x1 # Set IE
 
sw $t2,SS_STATUS($sp)
mtc0 $t0, $status
sw $t4, SS_STATUS($sp)
mtc0 $t2, $status
 
# CALL Syscall handler
#
# Call the higher level system call handler
# We are going to reuse part of the unused exception stack frame
#
sw $t0, STACK_ARG4($sp) # save the 5th argument on the stack
sw $t1, STACK_ARG5($sp) # save the 6th argument on the stack
jal syscall_handler
sw $v0, SS_ARG4($sp) # save v0 - arg4 to stack
sw $v0, STACK_ARG6($sp) # save the syscall number on the stack
 
# restore status
mfc0 $t0, $status
lw $t1,SS_STATUS($sp)
mfc0 $t2, $status
lw $t3, SS_STATUS($sp)
 
# Change back to EXL=1(from last exception), otherwise
# an interrupt could rewrite the CP0-EPC
li $t2, ~REG_SAVE_MASK # Mask UM,EXL,ERL,IE
and $t0, $t0, $t2
or $t0, $t0, $t1 # Copy UM,EXL,ERL,IE from saved status
mtc0 $t0, $status
# Change back to EXL = 1 (from last exception), otherwise
# an interrupt could rewrite the CP0 - EPC
li $t4, ~REG_SAVE_MASK # Mask UM, EXL, ERL, IE
and $t2, $t2, $t4
or $t2, $t2, $t3 # Copy saved UM, EXL, ERL, IE
mtc0 $t2, $status
# restore epc+4
lw $t0,SS_EPC($sp)
lw $k1,SS_K1($sp)
addi $t0, $t0, 4
mtc0 $t0, $epc
# restore epc + 4
lw $t2, SS_EPC($sp)
lw $k1, SS_K1($sp)
addi $t2, $t2, 4
mtc0 $t2, $epc
lw $sp,SS_SP($sp) # restore sp
lw $sp, SS_SP($sp) # restore sp
eret
333,5 → 349,5
userspace_asm:
add $sp, $a0, 0
add $v0, $a1, 0
add $t9, $a2, 0 # Set up correct entry into PIC code
add $t9, $a2, 0 # Set up correct entry into PIC code
eret