#include "config.h"
#include "cpu.h"
#include "crt0-common.S"
/* implement vectors, specify section and reset address */
RBIMPL_VECTORS .vectors, start
/* When starting, we will be running at 0x40000000 most probably
* but the code is expected to be loaded at 0x4xxxxxxx (uncached) and to be
* running at virtual address 0xyyyyyyyy (cached). So we first
* need to move everything to the right locationn then we setup the mmu and
* jump to the final virtual address. */
.text
.global start
/** The code below must be able to run at any address **/
start:
/* Copy running address */
sub r7, pc, #8
/* Save r0 */
mov r6, r0
RBIMPL_START_BEGIN
/* Disable MMU, disable caching and buffering;
* use low exception range address (the core uses high range by default) */
mrc p15, 0, r0, c1, c0, 0
ldr r1, =0x3005
bic r0, r1
mcr p15, 0, r0, c1, c0, 0
/* To call the C code we need a stack, since the stack is in virtual memory
* use the stack's physical address */
ldr sp, =stackend_phys
/* Enable MMU */
bl memory_init
/* Copy the DRAM
* Assume the dram binary blob is located at the loading address (r5) */
mov r2, r7
ldr r3, =_dramcopystart
ldr r4, =_dramcopyend
1:
cmp r4, r3
ldrhi r5, [r2], #4
strhi r5, [r3], #4
bhi 1b
mov r2, #0
mcr p15, 0, r2, c7, c5, 0 @ Invalidate ICache
/* Jump to real location */
ldr pc, =remap
remap:
RBIMPL_DO_STD_COPY _iedata, _iend, _iramcopy, _iramstart, _iramend, _initcopy, _initstart, _initend, _edata, _end
RBIMPL_INIT_STACKS stackend, stackbegin, iriq_stack, fiq_stack
RBIMPL_START_END
/* Jump to main */
mov r0, r6
mov r1, r7
bl main
1:
b 1b
RBIMPL_STD_HANDLERS
RBIMPL_IRQ_FIQ_STACKS irq_stack, fiq_stack
end: