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/*
* Copyright (c) 2018-2020, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <arch.h>
#include <asm_macros.S>
#include <console_macros.S>
#include <assert_macros.S>
#include "imx_uart.h"
#define URXD 0x0 /* Receiver Register */
#define UTXD 0x40 /* Transmitter Register */
#define USR2 0x98 /* UART Status Register 2 */
#define UTS 0xb4 /* UART Test Register (mx31) */
#define URXD_RX_DATA (0xFF)
.globl console_imx_uart_register
.globl console_imx_uart_init
.globl console_imx_uart_putc
.globl console_imx_uart_getc
.globl console_imx_uart_flush
func console_imx_uart_register
mov x7, x30
mov x6, x3
cbz x6, register_fail
str x0, [x6, #CONSOLE_T_BASE]
bl console_imx_uart_init
cbz x0, register_fail
mov x0, x6
mov x30, x7
finish_console_register imx_uart putc=1, getc=ENABLE_CONSOLE_GETC, flush=1
register_fail:
ret x7
endfunc console_imx_uart_register
func console_imx_uart_init
mov w0, #1
ret
endfunc console_imx_uart_init
func console_imx_uart_putc
ldr x1, [x1, #CONSOLE_T_BASE]
cbz x1, putc_error
/* Prepare '\r' to '\n' */
cmp w0, #0xA
b.ne 2f
1:
/* Check if the transmit FIFO is full */
ldr w2, [x1, #UTS]
tbnz w2, #4, 1b
mov w2, #0xD
str w2, [x1, #UTXD]
2:
/* Check if the transmit FIFO is full */
ldr w2, [x1, #UTS]
tbnz w2, #4, 2b
str w0, [x1, #UTXD]
ret
putc_error:
mov w0, #-1
ret
endfunc console_imx_uart_putc
func console_imx_uart_getc
ldr x0, [x0, #CONSOLE_T_BASE]
cbz x0, getc_error
1:
ldr w1, [x0, #UTS]
tbnz w1, #5, 1b
ldr w1, [x0, #URXD]
and w0, w1, #URXD_RX_DATA
ret
getc_error:
mov w0, #-1
ret
endfunc console_imx_uart_getc
func console_imx_uart_flush
ldr x0, [x0, #CONSOLE_T_BASE]
cbz x0, flush_exit
1:
/* Wait for the transmit complete bit */
ldr w1, [x0, #USR2]
tbz w1, #3, 1b
flush_exit:
ret
endfunc console_imx_uart_flush
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