xref: /rk3399_ARM-atf/include/arch/aarch32/console_macros.S (revision c948f77136c42a92d0bb660543a3600c36dcf7f1)
1/*
2 * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 */
6#ifndef CONSOLE_MACROS_S
7#define CONSOLE_MACROS_S
8
9#include <drivers/console.h>
10
11/*
12 * This macro encapsulates the common setup that has to be done at the end of
13 * a console driver's register function. It will register all of the driver's
14 * callbacks in the console_t structure and initialize the flags field (by
15 * default consoles are enabled for the "boot" and "crash" states, this can be
16 * changed after registration with the console_set_scope() function). It ends
17 * with a tail call that will include return to the caller.
18 * REQUIRES console_t pointer in x0 and a valid return address in x30.
19 */
20/*
21 * The USE_FINISH_CONSOLE_REG_2 guard is introduced to allow selection between
22 * the 2 variants of the finish_console_register macro and will be removed
23 * once the deprecated variant is removed.
24 */
25#ifndef USE_FINISH_CONSOLE_REG_2
26#if !ERROR_DEPRECATED
27	/* This version of the macro is deprecated. Use the new version */
28	.macro	finish_console_register _driver
29	/*
30	 * Add these weak definitions so we will automatically write a 0 if the
31	 * function doesn't exist. I'd rather use .ifdef but that only works if
32	 * the function was defined (not just declared .global) above this point
33	 * in the file, which we can't guarantee.
34	 */
35	.weak console_\_driver\()_putc
36	.weak console_\_driver\()_getc
37	.weak console_\_driver\()_flush
38
39	/* Don't use adrp on weak funcs! See GNU ld bugzilla issue 22589. */
40	ldr	r1, =console_\_driver\()_putc
41	str	r1, [r0, #CONSOLE_T_PUTC]
42	ldr	r1, =console_\_driver\()_getc
43	str	r1, [r0, #CONSOLE_T_GETC]
44	ldr	r1, =console_\_driver\()_flush
45	str	r1, [r0, #CONSOLE_T_FLUSH]
46	mov	r1, #(CONSOLE_FLAG_BOOT | CONSOLE_FLAG_CRASH)
47	str	r1, [r0, #CONSOLE_T_FLAGS]
48	b	console_register
49	.endm
50#endif /* ERROR_DEPRECATED */
51#else /* USE_FINISH_CONSOLE_REG_2 */
52	/* The new version of the macro not using weak references */
53	.macro	finish_console_register _driver, putc=0, getc=0, flush=0
54	/*
55	 * If any of the callback is not specified or set as 0, then the
56	 * corresponding callback entry in console_t is set to 0.
57	 */
58	.ifne \putc
59	  ldr	r1, =console_\_driver\()_putc
60	.else
61	  mov	r1, #0
62	.endif
63	str	r1, [r0, #CONSOLE_T_PUTC]
64
65	.ifne \getc
66	  ldr	r1, =console_\_driver\()_getc
67	.else
68	  mov	r1, #0
69	.endif
70	str	r1, [r0, #CONSOLE_T_GETC]
71
72	.ifne \flush
73	  ldr	r1, =console_\_driver\()_flush
74	.else
75	  mov	r1, #0
76	.endif
77	str	r1, [r0, #CONSOLE_T_FLUSH]
78
79	mov	r1, #(CONSOLE_FLAG_BOOT | CONSOLE_FLAG_CRASH)
80	str	r1, [r0, #CONSOLE_T_FLAGS]
81	b	console_register
82	.endm
83#endif /* USE_FINISH_CONSOLE_REG_2 */
84#endif /* CONSOLE_MACROS_S */
85