1/*
2 * Copyright (c) 2018-2020, ARM Limited and Contributors. All rights reserved.
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 */
6
7#include <arch.h>
8#include <asm_macros.S>
9#include <console_macros.S>
10#include <assert_macros.S>
11#include "imx_uart.h"
12
13#define URXD  0x0  /* Receiver Register */
14#define UTXD  0x40 /* Transmitter Register */
15#define UTS   0xb4 /* UART Test Register (mx31) */
16#define  URXD_RX_DATA    (0xFF)
17
18	.globl	console_imx_uart_register
19	.globl	console_imx_uart_init
20	.globl	console_imx_uart_putc
21	.globl	console_imx_uart_getc
22	.globl	console_imx_uart_flush
23
24func console_imx_uart_register
25	mov	x7, x30
26	mov	x6, x3
27	cbz	x6, register_fail
28	str	x0, [x6, #CONSOLE_T_BASE]
29
30	bl	console_imx_uart_init
31	cbz	x0, register_fail
32
33	mov	x0, x6
34	mov	x30, x7
35	finish_console_register imx_uart putc=1, getc=1, flush=1
36
37register_fail:
38	ret	x7
39endfunc console_imx_uart_register
40
41func console_imx_uart_init
42	mov	w0, #1
43	ret
44endfunc console_imx_uart_init
45
46func console_imx_uart_putc
47	ldr	x1, [x1, #CONSOLE_T_BASE]
48	cbz	x1, putc_error
49
50	/* Prepare '\r' to '\n' */
51	cmp	w0, #0xA
52	b.ne	2f
531:
54	/* Check if the transmit FIFO is full */
55	ldr	w2, [x1, #UTS]
56	tbz	w2, #6, 1b
57	mov	w2, #0xD
58	str	w2, [x1, #UTXD]
592:
60	/* Check if the transmit FIFO is full */
61	ldr	w2, [x1, #UTS]
62	tbz	w2, #6, 2b
63	str	w0, [x1, #UTXD]
64	ret
65putc_error:
66	mov	w0, #-1
67	ret
68endfunc console_imx_uart_putc
69
70func console_imx_uart_getc
71	ldr	x0, [x0, #CONSOLE_T_BASE]
72	cbz	x0, getc_error
731:
74	ldr	w1, [x0, #UTS]
75	tbnz	w1, #5, 1b
76
77	ldr	w1, [x0, #URXD]
78	and	w0, w1, #URXD_RX_DATA
79
80	ret
81getc_error:
82	mov	w0, #-1
83	ret
84endfunc console_imx_uart_getc
85
86func console_imx_uart_flush
87	ret
88endfunc console_imx_uart_flush
89