1 /*
2  * Copyright (c) 2013-2020, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #ifndef CONSOLE_H
8 #define CONSOLE_H
9 
10 #include <lib/utils_def.h>
11 
12 #define CONSOLE_T_NEXT			(U(0) * REGSZ)
13 #define CONSOLE_T_FLAGS			(U(1) * REGSZ)
14 #define CONSOLE_T_PUTC			(U(2) * REGSZ)
15 #define CONSOLE_T_GETC			(U(3) * REGSZ)
16 #define CONSOLE_T_FLUSH			(U(4) * REGSZ)
17 #define CONSOLE_T_BASE			(U(5) * REGSZ)
18 #define CONSOLE_T_DRVDATA		(U(6) * REGSZ)
19 
20 #define CONSOLE_FLAG_BOOT		(U(1) << 0)
21 #define CONSOLE_FLAG_RUNTIME		(U(1) << 1)
22 #define CONSOLE_FLAG_CRASH		(U(1) << 2)
23 /* Bits 3 to 7 reserved for additional scopes in future expansion. */
24 #define CONSOLE_FLAG_SCOPE_MASK		((U(1) << 8) - 1)
25 /* Bits 8 to 31 for non-scope use. */
26 #define CONSOLE_FLAG_TRANSLATE_CRLF	(U(1) << 8)
27 
28 /* Returned by getc callbacks when receive FIFO is empty. */
29 #define ERROR_NO_PENDING_CHAR		(-1)
30 /* Returned by console_xxx() if no registered console implements xxx. */
31 #define ERROR_NO_VALID_CONSOLE		(-128)
32 
33 #ifndef __ASSEMBLER__
34 
35 #include <stdint.h>
36 
37 typedef struct console {
38 	struct console *next;
39 	/*
40 	 * Only the low 32 bits are used. The type is u_register_t to align the
41 	 * fields of the struct to 64 bits in AArch64 and 32 bits in AArch32
42 	 */
43 	u_register_t flags;
44 	int (*const putc)(int character, struct console *console);
45 	int (*const getc)(struct console *console);
46 	void (*const flush)(struct console *console);
47 	uintptr_t base;
48 	/* Additional private driver data may follow here. */
49 } console_t;
50 
51 /* offset macro assertions for console_t */
52 #include <drivers/console_assertions.h>
53 
54 /*
55  * Add a console_t instance to the console list. This should only be called by
56  * console drivers after they have initialized all fields in the console
57  * structure. Platforms seeking to register a new console need to call the
58  * respective console__register() function instead.
59  */
60 int console_register(console_t *console);
61 /* Remove a single console_t instance from the console list. Return a pointer to
62  * the console that was removed if it was found, or NULL if not. */
63 console_t *console_unregister(console_t *console);
64 /* Returns 1 if this console is already registered, 0 if not */
65 int console_is_registered(console_t *console);
66 /*
67  * Set scope mask of a console that determines in what states it is active.
68  * By default they are registered with (CONSOLE_FLAG_BOOT|CONSOLE_FLAG_CRASH).
69  */
70 void console_set_scope(console_t *console, unsigned int scope);
71 
72 /* Switch to a new global console state (CONSOLE_FLAG_BOOT/RUNTIME/CRASH). */
73 void console_switch_state(unsigned int new_state);
74 /* Output a character on all consoles registered for the current state. */
75 int console_putc(int c);
76 /* Read a character (blocking) from any console registered for current state. */
77 int console_getc(void);
78 /* Flush all consoles registered for the current state. */
79 void console_flush(void);
80 
81 #endif /* __ASSEMBLER__ */
82 
83 #endif /* CONSOLE_H */
84