diff options
Diffstat (limited to 'tftf/framework/aarch32/asm_debug.S')
-rw-r--r-- | tftf/framework/aarch32/asm_debug.S | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/tftf/framework/aarch32/asm_debug.S b/tftf/framework/aarch32/asm_debug.S new file mode 100644 index 000000000..d2b2c79a3 --- /dev/null +++ b/tftf/framework/aarch32/asm_debug.S @@ -0,0 +1,126 @@ +/* + * Copyright (c) 2018, Arm Limited. All rights reserved. + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#include <arch.h> +#include <asm_macros.S> + +#if ENABLE_ASSERTIONS + + .globl asm_assert + +/* Since the max decimal input number is 65536 */ +#define MAX_DEC_DIVISOR 10000 + +/* The offset to add to get ascii for numerals '0 - 9' */ +#define ASCII_OFFSET_NUM '0' + +.section .rodata.assert_str, "aS" +assert_msg1: + .asciz "ASSERT: File " +assert_msg2: + .asciz " Line " + +/* --------------------------------------------------------------------------- + * Assertion support in assembly. + * The below function helps to support assertions in assembly where we do not + * have a C runtime stack. Arguments to the function are : + * r0 - File name + * r1 - Line no + * Clobber list : lr, r0 - r6 + * --------------------------------------------------------------------------- + */ +func asm_assert + /* + * Only print the output if LOG_LEVEL is higher or equal to + * LOG_LEVEL_INFO, which is the default value for builds with DEBUG=1. + */ + /* Stash the parameters already in r0 and r1 */ + mov r5, r0 + mov r6, r1 + + /* Initialize crash console and verify success */ + bl plat_crash_console_init + cmp r0, #0 + beq 1f + + /* Print file name */ + ldr r4, =assert_msg1 + bl asm_print_str + mov r4, r5 + bl asm_print_str + + /* Print line number string */ + ldr r4, =assert_msg2 + bl asm_print_str + + /* Test for maximum supported line number */ + ldr r4, =~0xffff + tst r6, r4 + bne 1f + mov r4, r6 + + /* Print line number in decimal */ + mov r6, #10 /* Divide by 10 after every loop iteration */ + ldr r5, =MAX_DEC_DIVISOR +dec_print_loop: + udiv r0, r4, r5 /* Quotient */ + mls r4, r0, r5, r4 /* Remainder */ + add r0, r0, #ASCII_OFFSET_NUM /* Convert to ASCII */ + bl plat_crash_console_putc + udiv r5, r5, r6 /* Reduce divisor */ + cmp r5, #0 + bne dec_print_loop + + bl plat_crash_console_flush + +1: + wfi + b 1b +endfunc asm_assert + +/* + * This function prints a string from address in r4 + * Clobber: lr, r0 - r4 + */ +func asm_print_str + mov r3, lr +1: + ldrb r0, [r4], #0x1 + cmp r0, #0 + beq 2f + bl plat_crash_console_putc + b 1b +2: + bx r3 +endfunc asm_print_str + +/* + * This function prints a hexadecimal number in r4. + * In: r4 = the hexadecimal to print. + * Clobber: lr, r0 - r3, r5 + */ +func asm_print_hex + mov r3, lr + mov r5, #32 /* No of bits to convert to ascii */ +1: + sub r5, r5, #4 + lsr r0, r4, r5 + and r0, r0, #0xf + cmp r0, #0xa + blo 2f + /* Add by 0x27 in addition to ASCII_OFFSET_NUM + * to get ascii for characters 'a - f'. + */ + add r0, r0, #0x27 +2: + add r0, r0, #ASCII_OFFSET_NUM + bl plat_crash_console_putc + cmp r5, #0 + bne 1b + bx r3 +endfunc asm_print_hex + +#endif /* ENABLE_ASSERTIONS */ |