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[/] [c0or1k/] [trunk/] [src/] [arch/] [arm/] [head.S.ARM] - Diff between revs 2 and 6

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Rev 2 Rev 6
?rev1line?
?rev2line?
 
/*
 
 * ARM Kernel entry point
 
 *
 
 * Copyright (C) 2007 Bahadir Balban
 
 */
 
 
 
#include INC_ARCH(asm.h)
 
 
 
#define C15_C0_M                0x0001  /* MMU */
 
#define C15_C0_A                0x0002  /* Alignment */
 
#define C15_C0_C                0x0004  /* (D) Cache */
 
#define C15_C0_W                0x0008  /* Write buffer */
 
#define C15_C0_B                0x0080  /* Endianness */
 
#define C15_C0_S                0x0100  /* System */
 
#define C15_C0_R                0x0200  /* ROM */
 
#define C15_C0_Z                0x0800  /* Branch Prediction */
 
#define C15_C0_I                0x1000  /* I cache */
 
#define C15_C0_V                0x2000  /* High vectors */
 
 
 
 
 
/*
 
 * This is the entry point of the L4 ARM architecture.
 
 * The boot loader must call _start with the processor in privileged
 
 * mode and mmu disabled.
 
 */
 
        .section .text.head
 
BEGIN_PROC(_start)
 
        /* Setup status register for supervisor mode, interrupts disabled */
 
        msr     cpsr_fcxs, #ARM_MODE_SVC
 
 
 
        /* Disable mmu if it is enabled */
 
        mrc     p15, 0, r0, c1, c0, 0
 
        bic     r0, r0, #C15_C0_M       @ Disable MMU
 
        bic     r0, r0, #C15_C0_C       @ Disable (D) Cache
 
        bic     r0, r0, #C15_C0_I       @ Disable I cache
 
        bic     r0, r0, #C15_C0_W       @ Disable Write buffer
 
        bic     r0, r0, #C15_C0_Z       @ Disable Branch prediction
 
        mcr     p15, 0, r0, c1, c0, 0
 
 
 
        /* Setup boot stack (physical address) */
 
        ldr     sp,     _kernel_init_stack
 
 
 
        /* Exception stacks are defined in vector page */
 
        msr     cpsr_fc, #ARM_NOIRQ_ABT
 
        ldr     sp,     _kernel_abt_stack
 
        msr     cpsr_fc, #ARM_NOIRQ_IRQ
 
        ldr     sp,     _kernel_irq_stack
 
        msr     cpsr_fc, #ARM_NOIRQ_FIQ
 
        ldr     sp,     _kernel_fiq_stack
 
        msr     cpsr_fc, #ARM_NOIRQ_UND
 
        ldr     sp,     _kernel_und_stack
 
        msr     cpsr_fc, #ARM_NOIRQ_SVC
 
 
 
        /* Jump to start_kernel */
 
        bl      start_kernel
 
 
 
        /* Never reached */
 
1:
 
        b       1b
 
 
 
_kernel_init_stack:
 
        .word   _bootstack_physical
 
 
 
/* Exception stacks are defined in vector page */
 
_kernel_abt_stack:
 
        .word   __abt_stack_high
 
_kernel_irq_stack:
 
        .word   __irq_stack_high
 
_kernel_fiq_stack:
 
        .word   __fiq_stack_high
 
_kernel_und_stack:
 
        .word   __und_stack_high

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