blob: 7cc04ddd7390f3f1ecf6a3676db6c2652a5800ba [file] [log] [blame]
/*
* Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <asm_macros.S>
.globl console_init
.globl console_uninit
.globl console_putc
.globl console_getc
.globl console_flush
/*
* The console base is in the data section and not in .bss
* even though it is zero-init. In particular, this allows
* the console functions to start using this variable before
* the runtime memory is initialized for images which do not
* need to copy the .data section from ROM to RAM.
*/
.section .data.console_base ; .align 3
console_base: .quad 0x0
/* -----------------------------------------------
* int console_init(uintptr_t base_addr,
* unsigned int uart_clk, unsigned int baud_rate)
* Function to initialize the console without a
* C Runtime to print debug information. It saves
* the console base to the data section.
* In: x0 - console base address
* w1 - Uart clock in Hz
* w2 - Baud rate
* out: return 1 on success else 0 on error
* Clobber list : x1 - x4
* -----------------------------------------------
*/
func console_init
/* Check the input base address */
cbz x0, init_fail
adrp x3, console_base
str x0, [x3, :lo12:console_base]
b console_core_init
init_fail:
ret
endfunc console_init
/* -----------------------------------------------
* void console_uninit(void)
* Function to finish the use of console driver.
* It sets the console_base as NULL so that any
* further invocation of `console_putc` or
* `console_getc` APIs would return error.
* -----------------------------------------------
*/
func console_uninit
mov x0, #0
adrp x3, console_base
str x0, [x3, :lo12:console_base]
ret
endfunc console_uninit
/* ---------------------------------------------
* int console_putc(int c)
* Function to output a character over the
* console. It returns the character printed on
* success or -1 on error.
* In : x0 - character to be printed
* Out : return -1 on error else return character.
* Clobber list : x1, x2
* ---------------------------------------------
*/
func console_putc
adrp x2, console_base
ldr x1, [x2, :lo12:console_base]
b console_core_putc
endfunc console_putc
/* ---------------------------------------------
* int console_getc(void)
* Function to get a character from the console.
* It returns the character grabbed on success
* or -1 on error.
* Clobber list : x0, x1
* ---------------------------------------------
*/
func console_getc
adrp x1, console_base
ldr x0, [x1, :lo12:console_base]
b console_core_getc
endfunc console_getc
/* ---------------------------------------------
* int console_flush(void)
* Function to force a write of all buffered
* data that hasn't been output. It returns 0
* upon successful completion, otherwise it
* returns -1.
* Clobber list : x0, x1
* ---------------------------------------------
*/
func console_flush
adrp x1, console_base
ldr x0, [x1, :lo12:console_base]
b console_core_flush
endfunc console_flush