| 43,7 → 43,10 |
|---|
| .global tlb_refill_entry |
| .global cache_error_entry |
| .global exception_entry |
| .global userspace_asm |
| |
| # Save registers to space defined by \r |
| # We will change $at on the way |
| .macro REGISTERS_STORE r |
| sw $at,EOFFSET_AT(\r) |
| sw $v0,EOFFSET_V0(\r) |
| 62,6 → 65,12 |
|---|
| sw $t7,EOFFSET_T7(\r) |
| sw $t8,EOFFSET_T8(\r) |
| sw $t9,EOFFSET_T9(\r) |
| |
| mflo $at |
| sw $at, EOFFSET_LO(\r) |
| mfhi $at |
| sw $at, EOFFSET_HI(\r) |
| |
| sw $s0,EOFFSET_S0(\r) |
| sw $s1,EOFFSET_S1(\r) |
| sw $s2,EOFFSET_S2(\r) |
| 73,14 → 82,13 |
|---|
| sw $s8,EOFFSET_S8(\r) |
| sw $gp,EOFFSET_GP(\r) |
| sw $ra,EOFFSET_RA(\r) |
| mflo $k0 |
| mfhi $k1 |
| sw $k0,EOFFSET_LO(\r) |
| sw $k1,EOFFSET_HI(\r) |
| sw $sp,EOFFSET_SP(\r) |
| |
| mfc0 $at, $status |
| sw $at,EOFFSET_STATUS(\r) |
| .endm |
| |
| .macro REGISTERS_LOAD r |
| lw $at,EOFFSET_AT(\r) |
| lw $v0,EOFFSET_V0(\r) |
| lw $v1,EOFFSET_V1(\r) |
| lw $a0,EOFFSET_A0(\r) |
| 109,13 → 117,37 |
|---|
| lw $gp,EOFFSET_GP(\r) |
| lw $ra,EOFFSET_RA(\r) |
| |
| lw $k0,EOFFSET_LO(\r) |
| lw $k1,EOFFSET_HI(\r) |
| mtlo $k0 |
| mthi $k1 |
| lw $at,EOFFSET_LO(\r) |
| mtlo $at |
| lw $at,EOFFSET_HI(\r) |
| mthi $at |
| |
| lw $at,EOFFSET_STATUS(\r) |
| mtc0 $at, $status |
| |
| lw $at,EOFFSET_AT(\r) |
| lw $sp,EOFFSET_SP(\r) |
| .endm |
| |
| # Move kernel stack pointer address to register K0 |
| # - if we are in user mode, load the appropriate stack |
| # address |
| .macro KERNEL_STACK_TO_K0 |
| # If we are in user mode |
| mfc0 $k0, $status |
| andi $k0, 0x10 |
| |
| beq $k0, $0, 1f |
| add $k0, $sp, 0 |
| |
| # Move $k0 pointer to kernel stack |
| lui $k0, %hi(supervisor_sp) |
| ori $k0, %lo(supervisor_sp) |
| # Move $k0 (superveisor_sp) |
| lw $k0, 0($k0) |
| 1: |
| .endm |
| |
| .org 0x0 |
| tlb_refill_entry: |
| j tlb_refill_handler |
| 127,25 → 159,20 |
|---|
| nop |
| |
| .org 0x180 |
| exception_entry: |
| exception_handler: |
| sub $sp, REGISTER_SPACE |
| REGISTERS_STORE $sp |
| norm_exception: |
| j exception_handler |
| nop |
| |
| jal exception |
| nop |
| .org 0x200 |
| iv_exception: |
| j exception_handler |
| nop |
| |
| REGISTERS_LOAD $sp |
| add $sp, REGISTER_SPACE |
| |
| eret |
| nop |
| |
| .org KA2PA(0x80000300) |
| .org KA2PA(KERNEL_STARTUP_ADDRESS) |
| kernel_image_start: |
| /* Load temporary stack */ |
| lui $sp, (TEMP_STACK_START + TEMP_STACK_SIZE) >> 16 |
| ori $sp, (TEMP_STACK_START + TEMP_STACK_SIZE) & 0xffff |
| lui $sp, %hi(end_stack) |
| ori $sp, $0, %lo(end_stack) |
| |
| /* Not sure about this, but might be needed for PIC code???? */ |
| lui $gp, 0x8000 |
| 153,31 → 180,56 |
|---|
| jal main_bsp |
| nop |
| |
| .org KA2PA(TEMP_STACK_START) |
| |
| .space TEMP_STACK_SIZE |
| end_stack: |
| |
| exception_handler: |
| exception_entry: |
| KERNEL_STACK_TO_K0 |
| sub $k0, REGISTER_SPACE |
| REGISTERS_STORE $k0 |
| add $sp, $k0, 0 |
| |
| jal exception |
| nop |
| |
| REGISTERS_LOAD $sp |
| # The $sp is automatically restored to former value |
| eret |
| nop |
| |
| tlb_refill_handler: |
| sub $sp, REGISTER_SPACE |
| REGISTERS_STORE $sp |
| KERNEL_STACK_TO_K0 |
| sub $k0, REGISTER_SPACE |
| REGISTERS_STORE $k0 |
| add $sp, $k0, 0 |
| |
| jal tlb_refill |
| nop |
| |
| REGISTERS_LOAD $sp |
| add $sp, REGISTER_SPACE |
| |
| eret |
| nop |
| |
| cache_error_handler: |
| KERNEL_STACK_TO_K0 |
| sub $sp, REGISTER_SPACE |
| REGISTERS_STORE $sp |
| add $sp, $k0, 0 |
| |
| jal cache_error |
| nop |
| |
| REGISTERS_LOAD $sp |
| add $sp, REGISTER_SPACE |
| |
| eret |
| nop |
| |
| userspace_asm: |
| .word 0x29 |
| add $sp, $a0, 0 |
| eret |
| nop |
| |