[934] | 1 | /** |
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| 2 | * File : reset.S |
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| 3 | * Author : Cesar FUGUET <cesar.fuguet-tortolero@lip6.fr> |
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| 4 | * Date : 16 October 2014 |
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| 5 | */ |
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| 6 | |
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| 7 | #include "hard_config.h" |
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| 8 | #include "cpu_registers.h" |
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| 9 | |
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| 10 | .section .reset,"ax",@progbits |
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| 11 | |
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| 12 | .extern seg_stack_base |
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| 13 | .extern seg_kcode_base |
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| 14 | .extern main |
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| 15 | |
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| 16 | .globl reset |
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| 17 | .ent reset |
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| 18 | .align 2 |
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| 19 | |
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| 20 | #define P_MASK ((1<<P_WIDTH)-1) |
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| 21 | #define Y_MASK ((1<<Y_WIDTH)-1) |
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| 22 | |
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[1016] | 23 | #define XCU_REG(func, idx) ((((func)<<5)|(idx)) << 2) |
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| 24 | #define XCU_CFG_REG 17 |
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| 25 | #define XCU_BARRIER 5 |
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| 26 | |
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| 27 | #define MEMC_REG(func,idx) (((func<<7)|idx) << 2) |
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| 28 | #define MEMC_CONFIG 0 |
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| 29 | #define MEMC_SCRATCHPAD 4 |
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| 30 | |
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[934] | 31 | reset: |
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| 32 | .set noreorder |
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| 33 | |
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| 34 | /* |
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| 35 | * SR register initialization |
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| 36 | * - Disable interrupts |
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| 37 | * - Keep the Bootstrap Exception Vector (BEV) bit set |
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| 38 | */ |
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| 39 | li k0, 0x00400000 |
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| 40 | mtc0 k0, CP0_STATUS |
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| 41 | |
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| 42 | /* |
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[1016] | 43 | * Get processor ID |
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[934] | 44 | */ |
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| 45 | mfc0 k0, CP0_PROCID |
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[1016] | 46 | andi k0, k0, 0xFFF /* k0 <= proc_xyl */ |
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[934] | 47 | |
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[1016] | 48 | /* |
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| 49 | * Release local gateway hardware barrier |
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| 50 | */ |
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| 51 | la k1, SEG_XCU_BASE /* k1 <= ICU base address */ |
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| 52 | li t0, XCU_REG(XCU_CFG_REG, XCU_BARRIER) |
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| 53 | or k1, k1, t0 /* k1 <= &XICU[CFG_REG][BARRIER] */ |
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| 54 | li t0, 0xFFFFFFFF |
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| 55 | sw t0, 0(k1) |
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| 56 | |
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| 57 | /* |
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| 58 | * Disable the scratchpad mode on the local memory cache |
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| 59 | */ |
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| 60 | la k1, SEG_MMC_BASE /* k1 <= MMC base address */ |
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| 61 | li t0, MEMC_REG(MEMC_CONFIG, MEMC_SCRATCHPAD) |
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| 62 | or k1, k1, t0 /* k1 <= &MEMC[CONFIG][SCRATCHPAD] */ |
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| 63 | sw zero, 0(k1) |
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| 64 | |
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| 65 | /* Only the processor 0 continues the execution */ |
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[934] | 66 | beqz k0, 1f |
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| 67 | nop |
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| 68 | wait |
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| 69 | |
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| 70 | 1: /* processor 0 initializes stack pointer (16K) */ |
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| 71 | la sp, _stack |
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[1016] | 72 | addiu sp, sp, (1<<14) /* sp <= _stack + 16K */ |
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[934] | 73 | |
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| 74 | /* jumps to main in kernel mode */ |
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| 75 | jal main |
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| 76 | nop |
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| 77 | |
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| 78 | j exit |
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| 79 | nop |
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| 80 | |
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| 81 | .set reorder |
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| 82 | .end reset |
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| 83 | |
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| 84 | |
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| 85 | |
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| 86 | .org 0x380 |
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| 87 | |
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| 88 | reset_exception_handler: |
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| 89 | mtc2 $0, MMU_DATA_PADDR_EXT |
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| 90 | j exception_handler |
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| 91 | |
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| 92 | |
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| 93 | |
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| 94 | .section .data |
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| 95 | |
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| 96 | /* |
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| 97 | * Stack segment definition |
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| 98 | */ |
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| 99 | _stack: |
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| 100 | .space (1<<14) /* 16 Kbytes */ |
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| 101 | |
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| 102 | /* |
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| 103 | * vim: tabstop=4 : softtabstop=4 : shiftwidth=4 : expandtab |
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| 104 | */ |
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