xref: /rk3399_ARM-atf/drivers/cadence/uart/aarch64/cdns_console.S (revision c948f77136c42a92d0bb660543a3600c36dcf7f1)
1/*
2 * Copyright (c) 2016-2017, 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 <drivers/cadence/cdns_uart.h>
12
13	/*
14	 * "core" functions are low-level implementations that don't require
15	 * writable memory and are thus safe to call in BL1 crash context.
16	 */
17	.globl console_cdns_core_init
18	.globl console_cdns_core_putc
19	.globl console_cdns_core_getc
20	.globl console_cdns_core_flush
21
22	.globl  console_cdns_putc
23	.globl  console_cdns_getc
24	.globl  console_cdns_flush
25
26	/* -----------------------------------------------
27	 * int console_cdns_core_init(uintptr_t base_addr)
28	 * Function to initialize the console without a
29	 * C Runtime to print debug information. This
30	 * function will be accessed by console_init and
31	 * crash reporting.
32	 * We assume that the bootloader already set up
33	 * the HW (baud, ...) and only enable the trans-
34	 * mitter and receiver here.
35	 * In: x0 - console base address
36	 * Out: return 1 on success else 0 on error
37	 * Clobber list : x1, x2, x3
38	 * -----------------------------------------------
39	 */
40func console_cdns_core_init
41	/* Check the input base address */
42	cbz	x0, core_init_fail
43
44	/* RX/TX enabled & reset */
45	mov	w3, #(R_UART_CR_TX_EN | R_UART_CR_RX_EN | R_UART_CR_TXRST | R_UART_CR_RXRST)
46	str	w3, [x0, #R_UART_CR]
47
48	mov	w0, #1
49	ret
50core_init_fail:
51	mov	w0, wzr
52	ret
53endfunc console_cdns_core_init
54
55#if MULTI_CONSOLE_API
56	.globl console_cdns_register
57
58	/* -----------------------------------------------
59	 * int console_cdns_register(uintptr_t baseaddr,
60	 *     uint32_t clock, uint32_t baud,
61	 *     console_cdns_t *console);
62	 * Function to initialize and register a new CDNS
63	 * console. Storage passed in for the console struct
64	 * *must* be persistent (i.e. not from the stack).
65	 * In: x0 - UART register base address
66	 *     w1 - UART clock in Hz
67	 *     w2 - Baud rate
68	 *     x3 - pointer to empty console_16550_t struct
69	 * Out: return 1 on success, 0 on error
70	 * Clobber list : x0, x1, x2, x6, x7, x14
71	 * -----------------------------------------------
72	 */
73func console_cdns_register
74	mov	x7, x30
75	mov	x6, x3
76	cbz	x6, register_fail
77	str	x0, [x6, #CONSOLE_T_CDNS_BASE]
78
79	bl	console_cdns_core_init
80	cbz	x0, register_fail
81
82	mov	x0, x6
83	mov	x30, x7
84	finish_console_register cdns putc=1, getc=1, flush=1
85
86register_fail:
87	ret	x7
88endfunc console_cdns_register
89#else
90	.globl console_core_init
91	.globl console_core_putc
92	.globl console_core_getc
93	.globl console_core_flush
94	.equ console_core_init,console_cdns_core_init
95	.equ console_core_putc,console_cdns_core_putc
96	.equ console_core_getc,console_cdns_core_getc
97	.equ console_core_flush,console_cdns_core_flush
98#endif
99
100	/* --------------------------------------------------------
101	 * int console_cdns_core_putc(int c, uintptr_t base_addr)
102	 * Function to output a character over the console. It
103	 * returns the character printed on success or -1 on error.
104	 * In : w0 - character to be printed
105	 *      x1 - console base address
106	 * Out : return -1 on error else return character.
107	 * Clobber list : x2
108	 * --------------------------------------------------------
109	 */
110func console_cdns_core_putc
111#if ENABLE_ASSERTIONS
112	cmp	x1, #0
113	ASM_ASSERT(ne)
114#endif /* ENABLE_ASSERTIONS */
115
116	/* Prepend '\r' to '\n' */
117	cmp	w0, #0xA
118	b.ne	2f
1191:
120	/* Check if the transmit FIFO is full */
121	ldr	w2, [x1, #R_UART_SR]
122	tbnz	w2, #UART_SR_INTR_TFUL_BIT, 1b
123	mov	w2, #0xD
124	str	w2, [x1, #R_UART_TX]
1252:
126	/* Check if the transmit FIFO is full */
127	ldr	w2, [x1, #R_UART_SR]
128	tbnz	w2, #UART_SR_INTR_TFUL_BIT, 2b
129	str	w0, [x1, #R_UART_TX]
130	ret
131endfunc console_cdns_core_putc
132
133	/* --------------------------------------------------------
134	 * int console_cdns_putc(int c, console_cdns_t *cdns)
135	 * Function to output a character over the console. It
136	 * returns the character printed on success or -1 on error.
137	 * In : w0 - character to be printed
138	 *      x1 - pointer to console_t structure
139	 * Out : return -1 on error else return character.
140	 * Clobber list : x2
141	 * --------------------------------------------------------
142	 */
143func console_cdns_putc
144#if ENABLE_ASSERTIONS
145	cmp	x1, #0
146	ASM_ASSERT(ne)
147#endif /* ENABLE_ASSERTIONS */
148	ldr	x1, [x1, #CONSOLE_T_CDNS_BASE]
149	b	console_cdns_core_putc
150endfunc console_cdns_putc
151
152	/* ---------------------------------------------
153	 * int console_cdns_core_getc(uintptr_t base_addr)
154	 * Function to get a character from the console.
155	 * It returns the character grabbed on success
156	 * or -1 if no character is available.
157	 * In : x0 - console base address
158	 * Out: w0 - character if available, else -1
159	 * Clobber list : x0, x1
160	 * ---------------------------------------------
161	 */
162func console_cdns_core_getc
163#if ENABLE_ASSERTIONS
164	cmp	x0, #0
165	ASM_ASSERT(ne)
166#endif /* ENABLE_ASSERTIONS */
167
168	/* Check if the receive FIFO is empty */
169	ldr	w1, [x0, #R_UART_SR]
170	tbnz	w1, #UART_SR_INTR_REMPTY_BIT, no_char
171	ldr	w1, [x0, #R_UART_RX]
172	mov	w0, w1
173	ret
174no_char:
175	mov	w0, #ERROR_NO_PENDING_CHAR
176	ret
177endfunc console_cdns_core_getc
178
179	/* ---------------------------------------------
180	 * int console_cdns_getc(console_cdns_t *console)
181	 * Function to get a character from the console.
182	 * It returns the character grabbed on success
183	 * or -1 if no character is available.
184	 * In : x0 - pointer to console_t structure
185	 * Out: w0 - character if available, else -1
186	 * Clobber list : x0, x1
187	 * ---------------------------------------------
188	 */
189func console_cdns_getc
190#if ENABLE_ASSERTIONS
191	cmp	x0, #0
192	ASM_ASSERT(ne)
193#endif /* ENABLE_ASSERTIONS */
194	ldr	x0, [x0, #CONSOLE_T_CDNS_BASE]
195	b	console_cdns_core_getc
196endfunc console_cdns_getc
197
198	/* ---------------------------------------------
199	 * int console_cdns_core_flush(uintptr_t base_addr)
200	 * Function to force a write of all buffered
201	 * data that hasn't been output.
202	 * In : x0 - console base address
203	 * Out : return -1 on error else return 0.
204	 * Clobber list : x0, x1
205	 * ---------------------------------------------
206	 */
207func console_cdns_core_flush
208#if ENABLE_ASSERTIONS
209	cmp	x0, #0
210	ASM_ASSERT(ne)
211#endif /* ENABLE_ASSERTIONS */
212	/* Placeholder */
213	mov	w0, #0
214	ret
215endfunc console_cdns_core_flush
216
217	/* ---------------------------------------------
218	 * int console_cdns_flush(console_pl011_t *console)
219	 * Function to force a write of all buffered
220	 * data that hasn't been output.
221	 * In : x0 - pointer to console_t structure
222	 * Out : return -1 on error else return 0.
223	 * Clobber list : x0, x1
224	 * ---------------------------------------------
225	 */
226func console_cdns_flush
227#if ENABLE_ASSERTIONS
228	cmp	x0, #0
229	ASM_ASSERT(ne)
230#endif /* ENABLE_ASSERTIONS */
231	ldr	x0, [x0, #CONSOLE_T_CDNS_BASE]
232	b	console_cdns_core_flush
233endfunc console_cdns_flush
234