xref: /rk3399_ARM-atf/drivers/arm/pl011/aarch64/pl011_console.S (revision 51faada71a219a8b94cd8d8e423f0f22e9da4d8f)
1/*
2 * Copyright (c) 2013-2016, ARM Limited and Contributors. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are met:
6 *
7 * Redistributions of source code must retain the above copyright notice, this
8 * list of conditions and the following disclaimer.
9 *
10 * Redistributions in binary form must reproduce the above copyright notice,
11 * this list of conditions and the following disclaimer in the documentation
12 * and/or other materials provided with the distribution.
13 *
14 * Neither the name of ARM nor the names of its contributors may be used
15 * to endorse or promote products derived from this software without specific
16 * prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGE.
29 */
30#include <arch.h>
31#include <asm_macros.S>
32#include <pl011.h>
33
34/*
35 * Pull in generic functions to provide backwards compatibility for
36 * platform makefiles
37 */
38#include "../../../console/aarch64/console.S"
39
40
41	.globl	console_core_init
42	.globl	console_core_putc
43	.globl	console_core_getc
44
45
46	/* -----------------------------------------------
47	 * int console_core_init(uintptr_t base_addr,
48	 * unsigned int uart_clk, unsigned int baud_rate)
49	 * Function to initialize the console without a
50	 * C Runtime to print debug information. This
51	 * function will be accessed by console_init and
52	 * crash reporting.
53	 * In: x0 - console base address
54	 *     w1 - Uart clock in Hz
55	 *     w2 - Baud rate
56	 * Out: return 1 on success else 0 on error
57	 * Clobber list : x1, x2, x3, x4
58	 * -----------------------------------------------
59	 */
60func console_core_init
61	/* Check the input base address */
62	cbz	x0, core_init_fail
63#if !PL011_GENERIC_UART
64	/* Check baud rate and uart clock for sanity */
65	cbz	w1, core_init_fail
66	cbz	w2, core_init_fail
67	/* Disable uart before programming */
68	ldr	w3, [x0, #UARTCR]
69	mov	w4, #PL011_UARTCR_UARTEN
70	bic	w3, w3, w4
71	str	w3, [x0, #UARTCR]
72	/* Program the baudrate */
73	/* Divisor =  (Uart clock * 4) / baudrate */
74	lsl	w1, w1, #2
75	udiv	w2, w1, w2
76	/* IBRD = Divisor >> 6 */
77	lsr	w1, w2, #6
78	/* Write the IBRD */
79	str	w1, [x0, #UARTIBRD]
80	/* FBRD = Divisor & 0x3F */
81	and	w1, w2, #0x3f
82	/* Write the FBRD */
83	str	w1, [x0, #UARTFBRD]
84	mov	w1, #PL011_LINE_CONTROL
85	str	w1, [x0, #UARTLCR_H]
86	/* Clear any pending errors */
87	str	wzr, [x0, #UARTECR]
88	/* Enable tx, rx, and uart overall */
89	mov	w1, #(PL011_UARTCR_RXE | PL011_UARTCR_TXE | PL011_UARTCR_UARTEN)
90	str	w1, [x0, #UARTCR]
91#endif
92	mov	w0, #1
93	ret
94core_init_fail:
95	mov	w0, wzr
96	ret
97endfunc console_core_init
98
99	/* --------------------------------------------------------
100	 * int console_core_putc(int c, uintptr_t base_addr)
101	 * Function to output a character over the console. It
102	 * returns the character printed on success or -1 on error.
103	 * In : w0 - character to be printed
104	 *      x1 - console base address
105	 * Out : return -1 on error else return character.
106	 * Clobber list : x2
107	 * --------------------------------------------------------
108	 */
109func console_core_putc
110	/* Check the input parameter */
111	cbz	x1, putc_error
112	/* Prepend '\r' to '\n' */
113	cmp	w0, #0xA
114	b.ne	2f
1151:
116	/* Check if the transmit FIFO is full */
117	ldr	w2, [x1, #UARTFR]
118	tbnz	w2, #PL011_UARTFR_TXFF_BIT, 1b
119	mov	w2, #0xD
120	str	w2, [x1, #UARTDR]
1212:
122	/* Check if the transmit FIFO is full */
123	ldr	w2, [x1, #UARTFR]
124	tbnz	w2, #PL011_UARTFR_TXFF_BIT, 2b
125	str	w0, [x1, #UARTDR]
126	ret
127putc_error:
128	mov	w0, #-1
129	ret
130endfunc console_core_putc
131
132	/* ---------------------------------------------
133	 * int console_core_getc(uintptr_t base_addr)
134	 * Function to get a character from the console.
135	 * It returns the character grabbed on success
136	 * or -1 on error.
137	 * In : x0 - console base address
138	 * Clobber list : x0, x1
139	 * ---------------------------------------------
140	 */
141func console_core_getc
142	cbz	x0, getc_error
1431:
144	/* Check if the receive FIFO is empty */
145	ldr	w1, [x0, #UARTFR]
146	tbnz	w1, #PL011_UARTFR_RXFE_BIT, 1b
147	ldr	w1, [x0, #UARTDR]
148	mov	w0, w1
149	ret
150getc_error:
151	mov	w0, #-1
152	ret
153endfunc console_core_getc
154