xref: /rk3399_ARM-atf/drivers/arm/pl011/aarch32/pl011_console.S (revision 0f58d4f2c8173e01ce3276fbc7bd981c3f23d902)
1/*
2 * Copyright (c) 2016-2018, 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#include <console_macros.S>
10#include <pl011.h>
11
12/*
13 * Pull in generic functions to provide backwards compatibility for
14 * platform makefiles
15 */
16#include "../../../console/aarch32/console.S"
17
18	/*
19	 * "core" functions are low-level implementations that don't require
20	 * writeable memory and are thus safe to call in BL1 crash context.
21	 */
22	.globl	console_pl011_core_init
23	.globl	console_pl011_core_putc
24	.globl	console_pl011_core_getc
25	.globl	console_pl011_core_flush
26
27	.globl	console_pl011_putc
28	.globl	console_pl011_getc
29	.globl	console_pl011_flush
30
31
32	/* -----------------------------------------------
33	 * int console_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: r0 - console base address
40	 *     r1 - Uart clock in Hz
41	 *     r2 - Baud rate
42	 * Out: return 1 on success else 0 on error
43	 * Clobber list : r1, r2, r3
44	 * -----------------------------------------------
45	 */
46func console_pl011_core_init
47	/* Check the input base address */
48	cmp	r0, #0
49	beq	core_init_fail
50#if !PL011_GENERIC_UART
51	/* Check baud rate and uart clock for sanity */
52	cmp	r1, #0
53	beq	core_init_fail
54	cmp	r2, #0
55	beq	core_init_fail
56	/* Disable the UART before initialization */
57	ldr	r3, [r0, #UARTCR]
58	bic	r3, r3, #PL011_UARTCR_UARTEN
59	str	r3, [r0, #UARTCR]
60	/* Program the baudrate */
61	/* Divisor =  (Uart clock * 4) / baudrate */
62	lsl	r1, r1, #2
63	udiv	r2, r1, r2
64	/* IBRD = Divisor >> 6 */
65	lsr	r1, r2, #6
66	/* Write the IBRD */
67	str	r1, [r0, #UARTIBRD]
68	/* FBRD = Divisor & 0x3F */
69	and	r1, r2, #0x3f
70	/* Write the FBRD */
71	str	r1, [r0, #UARTFBRD]
72	mov	r1, #PL011_LINE_CONTROL
73	str	r1, [r0, #UARTLCR_H]
74	/* Clear any pending errors */
75	mov	r1, #0
76	str	r1, [r0, #UARTECR]
77	/* Enable tx, rx, and uart overall */
78	ldr	r1, =(PL011_UARTCR_RXE | PL011_UARTCR_TXE | PL011_UARTCR_UARTEN)
79	str	r1, [r0, #UARTCR]
80#endif
81	mov	r0, #1
82	bx	lr
83core_init_fail:
84	mov	r0, #0
85	bx	lr
86endfunc console_pl011_core_init
87
88#if MULTI_CONSOLE_API
89	.globl console_pl011_register
90
91	/* -------------------------------------------------------
92	 * init console_pl011_register(console_pl011_t *console,
93	 *	uintptr_t base, uint32_t clk, uint32_t baud)
94	 * Function to initialize and register a new PL011
95	 * console. Storage passed in for the console struct
96	 * *must* be persistent (i.e. not from the stack).
97	 * In: r0 - UART register base address
98	 *     r1 - UART clock in Hz
99	 *     r2 - Baud rate
100	 *     r3 - pointer to empty console_pl011_t struct
101	 * Out: return 1 on success, 0 on error
102	 * Clobber list : r0, r1, r2
103	 * -------------------------------------------------------
104	 */
105func console_pl011_register
106	push	{r4, lr}
107	mov	r4, r3
108	cmp	r4, #0
109	beq	register_fail
110	str	r0, [r4, #CONSOLE_T_PL011_BASE]
111
112	bl console_pl011_core_init
113	cmp	r0, #0
114	beq	register_fail
115
116	mov	r0, r4
117	pop	{r4, lr}
118	finish_console_register pl011
119
120register_fail:
121	pop	{r4, pc}
122endfunc console_pl011_register
123#else
124	.globl console_core_init
125	.globl console_core_putc
126	.globl console_core_getc
127	.globl console_core_flush
128	.equ console_core_init, console_pl011_core_init
129	.equ console_core_putc, console_pl011_core_putc
130	.equ console_core_getc, console_pl011_core_getc
131	.equ console_core_flush, console_pl011_core_flush
132#endif
133
134	/* --------------------------------------------------------
135	 * int console_core_putc(int c, uintptr_t base_addr)
136	 * Function to output a character over the console. It
137	 * returns the character printed on success or -1 on error.
138	 * In : r0 - character to be printed
139	 *      r1 - console base address
140	 * Out : return -1 on error else return character.
141	 * Clobber list : r2
142	 * --------------------------------------------------------
143	 */
144func console_pl011_core_putc
145	/* Check the input parameter */
146	cmp	r1, #0
147	beq	putc_error
148	/* Prepend '\r' to '\n' */
149	cmp	r0, #0xA
150	bne	2f
1511:
152	/* Check if the transmit FIFO is full */
153	ldr	r2, [r1, #UARTFR]
154	tst	r2, #PL011_UARTFR_TXFF
155	bne	1b
156	mov	r2, #0xD
157	str	r2, [r1, #UARTDR]
1582:
159	/* Check if the transmit FIFO is full */
160	ldr	r2, [r1, #UARTFR]
161	tst	r2, #PL011_UARTFR_TXFF
162	bne	2b
163	str	r0, [r1, #UARTDR]
164	bx	lr
165putc_error:
166	mov	r0, #-1
167	bx	lr
168endfunc console_pl011_core_putc
169
170	/* --------------------------------------------------------
171	 * int console_pl011_putc(int c, console_pl011_t *console)
172	 * Function to output a character over the console. It
173	 * returns the character printed on success or -1 on error.
174	 * In: r0 - character to be printed
175	 *     r1 - pointer to console_t structure
176	 * Out : return -1 on error else return character.
177	 * Clobber list: r2
178	 * -------------------------------------------------------
179	 */
180func console_pl011_putc
181#if ENABLE_ASSERTIONS
182	cmp	r1, #0
183	ASM_ASSERT(ne)
184#endif /* ENABLE_ASSERTIONS */
185	ldr	r1, [r1, #CONSOLE_T_PL011_BASE]
186	b	console_pl011_core_putc
187endfunc console_pl011_putc
188
189	/* ---------------------------------------------
190	 * int console_core_getc(uintptr_t base_addr)
191	 * Function to get a character from the console.
192	 * It returns the character grabbed on success
193	 * or -1 on error.
194	 * In : r0 - console base address
195	 * Clobber list : r0, r1
196	 * ---------------------------------------------
197	 */
198func console_pl011_core_getc
199	cmp	r0, #0
200	beq	getc_error
2011:
202	/* Check if the receive FIFO is empty */
203	ldr	r1, [r0, #UARTFR]
204	tst	r1, #PL011_UARTFR_RXFE
205	bne	1b
206	ldr	r1, [r0, #UARTDR]
207	mov	r0, r1
208	bx	lr
209getc_error:
210	mov	r0, #-1
211	bx	lr
212endfunc console_pl011_core_getc
213
214	/* ------------------------------------------------
215	 * int console_pl011_getc(console_pl011_t *console)
216	 * Function to get a character from the console.
217	 * It returns the character grabbed on success
218	 * or -1 if no character is available.
219	 * In : r0 - pointer to console_t structure
220	 * Out: r0 - character if available, else -1
221	 * Clobber list: r0, r1
222	 * ------------------------------------------------
223	 */
224func console_pl011_getc
225#if ENABLE_ASSERTIONS
226	cmp	r0, #0
227	ASM_ASSERT(ne)
228#endif /* ENABLE_ASSERTIONS */
229	ldr	r0, [r0, #CONSOLE_T_PL011_BASE]
230	b	console_pl011_core_getc
231endfunc console_pl011_getc
232
233	/* ---------------------------------------------
234	 * int console_core_flush(uintptr_t base_addr)
235	 * Function to force a write of all buffered
236	 * data that hasn't been output.
237	 * In : r0 - console base address
238	 * Out : return -1 on error else return 0.
239	 * Clobber list : r0, r1
240	 * ---------------------------------------------
241	 */
242func console_pl011_core_flush
243	cmp	r0, #0
244	beq	flush_error
245
2461:
247	/* Loop while the transmit FIFO is busy */
248	ldr	r1, [r0, #UARTFR]
249	tst	r1, #PL011_UARTFR_BUSY
250	bne	1b
251
252	mov	r0, #0
253	bx	lr
254flush_error:
255	mov	r0, #-1
256	bx	lr
257endfunc console_pl011_core_flush
258
259	/* ---------------------------------------------
260	 * int console_pl011_flush(console_pl011_t *console)
261	 * Function to force a write of all buffered
262	 * data that hasn't been output.
263	 * In : r0 - pointer to console_t structure
264	 * Out : return -1 on error else return 0.
265	 * Clobber list: r0, r1
266	 * ---------------------------------------------
267	 */
268func console_pl011_flush
269#if ENABLE_ASSERTIONS
270	cmp	r0, #0
271	ASM_ASSERT(ne)
272#endif /* ENABLE_ASSERTIONS */
273	ldr	r0, [r0, #CONSOLE_T_PL011_BASE]
274	b	console_pl011_core_flush
275endfunc console_pl011_flush
276