| 49,7 → 49,6 |
|---|
| # Save registers to space defined by \r |
| # We will change status: Disable ERL,EXL,UM,IE |
| # 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) |
| 88,7 → 87,7 |
|---|
| |
| sw $gp,EOFFSET_GP(\r) |
| sw $ra,EOFFSET_RA(\r) |
| sw $k1,EOFFSET_K1(\r) |
| sw $sp,EOFFSET_SP(\r) |
| |
| mfc0 $t0, $status |
| mfc0 $t1, $epc |
| 144,7 → 143,6 |
|---|
| #endif |
| lw $gp,EOFFSET_GP(\r) |
| lw $ra,EOFFSET_RA(\r) |
| lw $k1,EOFFSET_K1(\r) |
| |
| lw $at,EOFFSET_LO(\r) |
| mtlo $at |
| 209,24 → 207,23 |
|---|
| |
| exception_handler: |
| KERNEL_STACK_TO_K0 |
| |
| mfc0 $k1, $cause |
| sub $k0, REGISTER_SPACE |
| sw $sp,EOFFSET_SP($k0) |
| move $sp, $k0 |
| |
| mfc0 $k0, $cause |
| sra $k1, $k1, 0x2 # cp0_exc_cause() part 1 |
| andi $k1, $k1, 0x1f # cp0_exc_cause() part 2 |
| sub $k1, 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 $k1, syscall_shortcut |
| add $k1, 8 # Revert $k1 back to correct exc number |
| |
| beqz $k0, syscall_shortcut |
| add $k0, 8 # Revert $k1 back to correct exc number |
| REGISTERS_STORE_AND_EXC_RESET $k0 |
| move $sp, $k0 |
| |
| REGISTERS_STORE_AND_EXC_RESET $sp |
| |
| move $a1, $sp |
| jal exc_dispatch # exc_dispatch(excno, register_space) |
| move $a0, $k0 |
| move $a0, $k1 |
| |
| REGISTERS_LOAD $sp |
| # The $sp is automatically restored to former value |
| 234,11 → 231,14 |
|---|
| |
| # 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_SP 20 |
| #define SS_STATUS 24 |
| #define SS_EPC 28 |
| syscall_shortcut: |
| # We have a lot of space on the stack, with free use |
| sw $sp, SS_SP($k0) |
| move $sp, $k0 |
| |
| mfc0 $t1, $epc |
| mfc0 $t0, $status |
| sw $t1,SS_EPC($sp) # Save EPC |
| 276,7 → 276,6 |
|---|
| KERNEL_STACK_TO_K0 |
| sub $k0, REGISTER_SPACE |
| REGISTERS_STORE_AND_EXC_RESET $k0 |
| sw $sp,EOFFSET_SP($k0) |
| add $sp, $k0, 0 |
| |
| add $a0, $sp, 0 |
| 289,9 → 288,8 |
|---|
| |
| cache_error_handler: |
| KERNEL_STACK_TO_K0 |
| sub $k0, REGISTER_SPACE |
| REGISTERS_STORE_AND_EXC_RESET $k0 |
| sw $sp,EOFFSET_SP($k0) |
| sub $sp, REGISTER_SPACE |
| REGISTERS_STORE_AND_EXC_RESET $sp |
| add $sp, $k0, 0 |
| |
| jal cache_error |