xref: /rk3399_ARM-atf/drivers/arm/pl011/aarch64/pl011_console.S (revision ecc35992f3a996420f98a268a11959a6656fd02d)
1/*
2 * Copyright (c) 2013-2017, ARM Limited and Contributors. All rights reserved.
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 */
6#include <arch.h>
7#include <asm_macros.S>
8#include <assert_macros.S>
9#define USE_FINISH_CONSOLE_REG_2
10#include <console_macros.S>
11#include <pl011.h>
12
13/*
14 * Pull in generic functions to provide backwards compatibility for
15 * platform makefiles
16 */
17#include "../../../console/aarch64/console.S"
18
19	/*
20	 * "core" functions are low-level implementations that don't require
21	 * writable memory and are thus safe to call in BL1 crash context.
22	 */
23	.globl console_pl011_core_init
24	.globl console_pl011_core_putc
25	.globl console_pl011_core_getc
26	.globl console_pl011_core_flush
27
28	.globl	console_pl011_putc
29	.globl	console_pl011_getc
30	.globl	console_pl011_flush
31
32	/* -----------------------------------------------
33	 * int console_pl011_core_init(uintptr_t base_addr,
34	 * unsigned int uart_clk, unsigned int baud_rate)
35	 * Function to initialize the console without a
36	 * C Runtime to print debug information. This
37	 * function will be accessed by console_init and
38	 * crash reporting.
39	 * In: x0 - console base address
40	 *     w1 - Uart clock in Hz
41	 *     w2 - Baud rate
42	 * Out: return 1 on success else 0 on error
43	 * Clobber list : x1, x2, x3, x4
44	 * -----------------------------------------------
45	 */
46func console_pl011_core_init
47	/* Check the input base address */
48	cbz	x0, core_init_fail
49#if !PL011_GENERIC_UART
50	/* Check baud rate and uart clock for sanity */
51	cbz	w1, core_init_fail
52	cbz	w2, core_init_fail
53	/* Disable uart before programming */
54	ldr	w3, [x0, #UARTCR]
55	mov	w4, #PL011_UARTCR_UARTEN
56	bic	w3, w3, w4
57	str	w3, [x0, #UARTCR]
58	/* Program the baudrate */
59	/* Divisor =  (Uart clock * 4) / baudrate */
60	lsl	w1, w1, #2
61	udiv	w2, w1, w2
62	/* IBRD = Divisor >> 6 */
63	lsr	w1, w2, #6
64	/* Write the IBRD */
65	str	w1, [x0, #UARTIBRD]
66	/* FBRD = Divisor & 0x3F */
67	and	w1, w2, #0x3f
68	/* Write the FBRD */
69	str	w1, [x0, #UARTFBRD]
70	mov	w1, #PL011_LINE_CONTROL
71	str	w1, [x0, #UARTLCR_H]
72	/* Clear any pending errors */
73	str	wzr, [x0, #UARTECR]
74	/* Enable tx, rx, and uart overall */
75	mov	w1, #(PL011_UARTCR_RXE | PL011_UARTCR_TXE | PL011_UARTCR_UARTEN)
76	str	w1, [x0, #UARTCR]
77#endif
78	mov	w0, #1
79	ret
80core_init_fail:
81	mov	w0, wzr
82	ret
83endfunc console_pl011_core_init
84
85#if MULTI_CONSOLE_API
86	.globl console_pl011_register
87
88	/* -----------------------------------------------
89	 * int console_pl011_register(uintptr_t baseaddr,
90	 *     uint32_t clock, uint32_t baud,
91	 *     console_pl011_t *console);
92	 * Function to initialize and register a new PL011
93	 * console. Storage passed in for the console struct
94	 * *must* be persistent (i.e. not from the stack).
95	 * In: x0 - UART register base address
96	 *     w1 - UART clock in Hz
97	 *     w2 - Baud rate
98	 *     x3 - pointer to empty console_pl011_t struct
99	 * Out: return 1 on success, 0 on error
100	 * Clobber list : x0, x1, x2, x6, x7, x14
101	 * -----------------------------------------------
102	 */
103func console_pl011_register
104	mov	x7, x30
105	mov	x6, x3
106	cbz	x6, register_fail
107	str	x0, [x6, #CONSOLE_T_PL011_BASE]
108
109	bl	console_pl011_core_init
110	cbz	x0, register_fail
111
112	mov	x0, x6
113	mov	x30, x7
114	finish_console_register pl011 putc=1, getc=1, flush=1
115
116register_fail:
117	ret	x7
118endfunc console_pl011_register
119#else
120	.globl console_core_init
121	.globl console_core_putc
122	.globl console_core_getc
123	.globl console_core_flush
124	.equ console_core_init,console_pl011_core_init
125	.equ console_core_putc,console_pl011_core_putc
126	.equ console_core_getc,console_pl011_core_getc
127	.equ console_core_flush,console_pl011_core_flush
128#endif
129
130	/* --------------------------------------------------------
131	 * int console_pl011_core_putc(int c, uintptr_t base_addr)
132	 * Function to output a character over the console. It
133	 * returns the character printed on success or -1 on error.
134	 * In : w0 - character to be printed
135	 *      x1 - console base address
136	 * Out : return -1 on error else return character.
137	 * Clobber list : x2
138	 * --------------------------------------------------------
139	 */
140func console_pl011_core_putc
141#if ENABLE_ASSERTIONS
142	cmp	x1, #0
143	ASM_ASSERT(ne)
144#endif /* ENABLE_ASSERTIONS */
145
146	/* Prepend '\r' to '\n' */
147	cmp	w0, #0xA
148	b.ne	2f
1491:
150	/* Check if the transmit FIFO is full */
151	ldr	w2, [x1, #UARTFR]
152	tbnz	w2, #PL011_UARTFR_TXFF_BIT, 1b
153	mov	w2, #0xD
154	str	w2, [x1, #UARTDR]
1552:
156	/* Check if the transmit FIFO is full */
157	ldr	w2, [x1, #UARTFR]
158	tbnz	w2, #PL011_UARTFR_TXFF_BIT, 2b
159	str	w0, [x1, #UARTDR]
160	ret
161endfunc console_pl011_core_putc
162
163	/* --------------------------------------------------------
164	 * int console_pl011_putc(int c, console_pl011_t *console)
165	 * Function to output a character over the console. It
166	 * returns the character printed on success or -1 on error.
167	 * In : w0 - character to be printed
168	 *      x1 - pointer to console_t structure
169	 * Out : return -1 on error else return character.
170	 * Clobber list : x2
171	 * --------------------------------------------------------
172	 */
173func console_pl011_putc
174#if ENABLE_ASSERTIONS
175	cmp	x1, #0
176	ASM_ASSERT(ne)
177#endif /* ENABLE_ASSERTIONS */
178	ldr	x1, [x1, #CONSOLE_T_PL011_BASE]
179	b	console_pl011_core_putc
180endfunc console_pl011_putc
181
182	/* ---------------------------------------------
183	 * int console_pl011_core_getc(uintptr_t base_addr)
184	 * Function to get a character from the console.
185	 * It returns the character grabbed on success
186	 * or -1 if no character is available.
187	 * In : x0 - console base address
188	 * Out: w0 - character if available, else -1
189	 * Clobber list : x0, x1
190	 * ---------------------------------------------
191	 */
192func console_pl011_core_getc
193#if ENABLE_ASSERTIONS
194	cmp	x0, #0
195	ASM_ASSERT(ne)
196#endif /* ENABLE_ASSERTIONS */
197
198	/* Check if the receive FIFO is empty */
199	ldr	w1, [x0, #UARTFR]
200	tbnz	w1, #PL011_UARTFR_RXFE_BIT, no_char
201	ldr	w1, [x0, #UARTDR]
202	mov	w0, w1
203	ret
204no_char:
205	mov	w0, #ERROR_NO_PENDING_CHAR
206	ret
207endfunc console_pl011_core_getc
208
209	/* ---------------------------------------------
210	 * int console_pl011_getc(console_pl011_t *console)
211	 * Function to get a character from the console.
212	 * It returns the character grabbed on success
213	 * or -1 if no character is available.
214	 * In : x0 - pointer to console_t structure
215	 * Out: w0 - character if available, else -1
216	 * Clobber list : x0, x1
217	 * ---------------------------------------------
218	 */
219func console_pl011_getc
220#if ENABLE_ASSERTIONS
221	cmp	x0, #0
222	ASM_ASSERT(ne)
223#endif /* ENABLE_ASSERTIONS */
224	ldr	x0, [x0, #CONSOLE_T_PL011_BASE]
225	b	console_pl011_core_getc
226endfunc console_pl011_getc
227
228	/* ---------------------------------------------
229	 * int console_pl011_core_flush(uintptr_t base_addr)
230	 * Function to force a write of all buffered
231	 * data that hasn't been output.
232	 * In : x0 - console base address
233	 * Out : return -1 on error else return 0.
234	 * Clobber list : x0, x1
235	 * ---------------------------------------------
236	 */
237func console_pl011_core_flush
238#if ENABLE_ASSERTIONS
239	cmp	x0, #0
240	ASM_ASSERT(ne)
241#endif /* ENABLE_ASSERTIONS */
2421:
243	/* Loop until the transmit FIFO is empty */
244	ldr	w1, [x0, #UARTFR]
245	tbnz	w1, #PL011_UARTFR_BUSY_BIT, 1b
246
247	mov	w0, #0
248	ret
249endfunc console_pl011_core_flush
250
251	/* ---------------------------------------------
252	 * int console_pl011_flush(console_pl011_t *console)
253	 * Function to force a write of all buffered
254	 * data that hasn't been output.
255	 * In : x0 - pointer to console_t structure
256	 * Out : return -1 on error else return 0.
257	 * Clobber list : x0, x1
258	 * ---------------------------------------------
259	 */
260func console_pl011_flush
261#if ENABLE_ASSERTIONS
262	cmp	x0, #0
263	ASM_ASSERT(ne)
264#endif /* ENABLE_ASSERTIONS */
265	ldr	x0, [x0, #CONSOLE_T_PL011_BASE]
266	b	console_pl011_core_flush
267endfunc console_pl011_flush
268