1/*
2 * Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 */
6
7#include <arch.h>
8#include <asm_macros.S>
9
10	.globl	asm_assert
11	.globl	do_panic
12	.globl	report_exception
13
14/* Since the max decimal input number is 65536 */
15#define MAX_DEC_DIVISOR		10000
16
17/* The offset to add to get ascii for numerals '0 - 9' */
18#define ASCII_OFFSET_NUM	'0'
19
20	.section .rodata.panic_str, "aS"
21panic_msg:
22	.asciz "PANIC at PC : 0x"
23panic_end:
24	.asciz "\r\n"
25
26	/***********************************************************
27	 * The common implementation of do_panic for all BL stages
28	 ***********************************************************/
29func do_panic
30	/* Have LR copy point to PC at the time of panic */
31	sub	r6, lr, #4
32
33	/* Initialize crash console and verify success */
34	bl	plat_crash_console_init
35	cmp	r0, #0
36	beq	1f
37
38	/* Print panic message */
39	ldr	r4, =panic_msg
40	bl	asm_print_str
41
42	/* Print LR in hex */
43	mov	r4, r6
44	bl	asm_print_hex
45
46	/* Print new line */
47	ldr	r4, =panic_end
48	bl	asm_print_str
49
50	bl	plat_crash_console_flush
51
521:
53	mov	lr, r6
54	b	plat_panic_handler
55endfunc do_panic
56
57	/***********************************************************
58	 * This function is called from the vector table for
59	 * unhandled exceptions. It reads the current mode and
60	 * passes it to platform.
61	 ***********************************************************/
62func report_exception
63	mrs	r0, cpsr
64	and	r0, #MODE32_MASK
65	bl	plat_report_exception
66	no_ret	plat_panic_handler
67endfunc report_exception
68
69#if ENABLE_ASSERTIONS
70.section .rodata.assert_str, "aS"
71assert_msg1:
72	.asciz "ASSERT: File "
73assert_msg2:
74	.asciz " Line "
75
76/* ---------------------------------------------------------------------------
77 * Assertion support in assembly.
78 * The below function helps to support assertions in assembly where we do not
79 * have a C runtime stack. Arguments to the function are :
80 * r0 - File name
81 * r1 - Line no
82 * Clobber list : lr, r0 - r6
83 * ---------------------------------------------------------------------------
84 */
85func asm_assert
86#if LOG_LEVEL >= LOG_LEVEL_INFO
87	/*
88	 * Only print the output if LOG_LEVEL is higher or equal to
89	 * LOG_LEVEL_INFO, which is the default value for builds with DEBUG=1.
90	 */
91	/* Stash the parameters already in r0 and r1 */
92	mov	r5, r0
93	mov	r6, r1
94
95	/* Initialize crash console and verify success */
96	bl	plat_crash_console_init
97	cmp	r0, #0
98	beq	1f
99
100	/* Print file name */
101	ldr	r4, =assert_msg1
102	bl	asm_print_str
103	mov	r4, r5
104	bl	asm_print_str
105
106	/* Print line number string */
107	ldr	r4, =assert_msg2
108	bl	asm_print_str
109
110	/* Test for maximum supported line number */
111	ldr	r4, =~0xffff
112	tst	r6, r4
113	bne	1f
114	mov	r4, r6
115
116	/* Print line number in decimal */
117	mov	r6, #10			/* Divide by 10 after every loop iteration */
118	ldr	r5, =MAX_DEC_DIVISOR
119dec_print_loop:
120	udiv	r0, r4, r5			/* Quotient */
121	mls	r4, r0, r5, r4			/* Remainder */
122	add	r0, r0, #ASCII_OFFSET_NUM	/* Convert to ASCII */
123	bl	plat_crash_console_putc
124	udiv	r5, r5, r6			/* Reduce divisor */
125	cmp	r5, #0
126	bne	dec_print_loop
127
128	bl	plat_crash_console_flush
129
1301:
131#endif /* LOG_LEVEL >= LOG_LEVEL_INFO */
132	no_ret	plat_panic_handler
133endfunc asm_assert
134#endif /* ENABLE_ASSERTIONS */
135
136/*
137 * This function prints a string from address in r4
138 * Clobber: lr, r0 - r4
139 */
140func asm_print_str
141	mov	r3, lr
1421:
143	ldrb	r0, [r4], #0x1
144	cmp	r0, #0
145	beq	2f
146	bl	plat_crash_console_putc
147	b	1b
1482:
149	bx	r3
150endfunc asm_print_str
151
152/*
153 * This function prints a hexadecimal number in r4.
154 * In: r4 = the hexadecimal to print.
155 * Clobber: lr, r0 - r3, r5
156 */
157func asm_print_hex
158	mov	r3, lr
159	mov	r5, #32  /* No of bits to convert to ascii */
1601:
161	sub	r5, r5, #4
162	lsr	r0, r4, r5
163	and	r0, r0, #0xf
164	cmp	r0, #0xa
165	blo	2f
166	/* Add by 0x27 in addition to ASCII_OFFSET_NUM
167	 * to get ascii for characters 'a - f'.
168	 */
169	add	r0, r0, #0x27
1702:
171	add	r0, r0, #ASCII_OFFSET_NUM
172	bl	plat_crash_console_putc
173	cmp	r5, #0
174	bne	1b
175	bx	r3
176endfunc asm_print_hex
177