X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?p=rpikern;a=blobdiff_plain;f=src%2Fstartup.s;h=84e7e94d0b4037cec5229b228900e0f530504cec;hp=3feac3de968cbd2fb2c2df680eaf33893079fca0;hb=38a008b8d1a3a20c401397b4e132fb578e5f0c10;hpb=99bdc8838f189f79ba77bfbbf41d7f1b4839ce0f diff --git a/src/startup.s b/src/startup.s index 3feac3d..84e7e94 100644 --- a/src/startup.s +++ b/src/startup.s @@ -3,14 +3,37 @@ .section .startup .code 32 + .global startup startup: + cpsid if + @ stop all but one of the cores mrc p15, 0, r0, c0, c0, 5 ands r0, r0, #0xff bne exit - @ setup stack - ldr sp, =_stacktop + @ detect if we're running in hyp mode, and drop to svc + mrs r0, cpsr + and r1, r0, #0x1f + cmp r1, #0x1a + bne hypend + + bic r0, #0x1f + orr r0, #0x13 + @msr spsr_cxsf, r0 + add r0, pc, #4 + msr elr_hyp, r0 + @eret + mov pc, r0 +hypend: + + @ setup initial stacks, allow 4k stack for IRQs + @mov r0, #0x12 @ switch to IRQ mode + @msr cpsr, r0 + @ldr sp, =_stacktop + @mov r0, #0x13 @ switch to supervisor mode + @msr cpsr, r0 + ldr sp, =_stacktop - 4096 @ clear bss ldr r0, =_bss_start