mirror of
https://github.com/fergalmoran/ladybird.git
synced 2026-04-19 02:57:23 +00:00
fdc86ddae5
This allows configuring the alternate pin functions and pin pull up/down states, which is needed for using the UART.
34 lines
720 B
ArmAsm
34 lines
720 B
ArmAsm
/*
|
|
* Copyright (c) 2021, Nico Weber <thakis@chromium.org>
|
|
*
|
|
* SPDX-License-Identifier: BSD-2-Clause
|
|
*/
|
|
|
|
.text
|
|
|
|
.global start
|
|
.type start, @function
|
|
start:
|
|
// Let only core 0 continue, put other cores to sleep.
|
|
mrs x13, MPIDR_EL1
|
|
and x13, x13, 0xff
|
|
cbnz x13, halt
|
|
|
|
// Let stack start before .text for now.
|
|
// 512 kiB (0x8000) of stack are probably not sufficient, especially once we give the other cores some stack too,
|
|
// but for now it's ok.
|
|
ldr x14, =start
|
|
mov sp, x14
|
|
|
|
b init
|
|
|
|
.globl wait_cycles
|
|
.type wait_cycles, @function
|
|
wait_cycles:
|
|
Lstart:
|
|
// This is probably too fast when caching and branch prediction is turned on.
|
|
// FIXME: Make timer-based.
|
|
subs x0, x0, #1
|
|
bne Lstart
|
|
ret
|