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Diffstat (limited to 'common/aarch64/debug.S')
| -rw-r--r-- | common/aarch64/debug.S | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/common/aarch64/debug.S b/common/aarch64/debug.S new file mode 100644 index 0000000..742e022 --- /dev/null +++ b/common/aarch64/debug.S @@ -0,0 +1,221 @@ +/* + * Copyright (c) 2014-2020, ARM Limited and Contributors. All rights reserved. + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#include <arch.h> +#include <asm_macros.S> +#include <common/debug.h> + + .globl asm_print_str + .globl asm_print_hex + .globl asm_print_hex_bits + .globl asm_print_newline + .globl asm_assert + .globl do_panic + +/* 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 0x30 + +#if ENABLE_ASSERTIONS +.section .rodata.assert_str, "aS" +assert_msg1: + .asciz "ASSERT: File " +assert_msg2: + .asciz " Line " + + /* + * This macro is intended to be used to print the + * line number in decimal. Used by asm_assert macro. + * The max number expected is 65536. + * In: x4 = the decimal to print. + * Clobber: x30, x0, x1, x2, x5, x6 + */ + .macro asm_print_line_dec + mov x6, #10 /* Divide by 10 after every loop iteration */ + mov x5, #MAX_DEC_DIVISOR +dec_print_loop: + udiv x0, x4, x5 /* Get the quotient */ + msub x4, x0, x5, x4 /* Find the remainder */ + add x0, x0, #ASCII_OFFSET_NUM /* Convert to ascii */ + bl plat_crash_console_putc + udiv x5, x5, x6 /* Reduce divisor */ + cbnz x5, dec_print_loop + .endm + + +/* --------------------------------------------------------------------------- + * 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 : + * x0 - File name + * x1 - Line no + * Clobber list : x30, x0, x1, x2, x3, x4, x5, x6. + * --------------------------------------------------------------------------- + */ +func asm_assert +#if LOG_LEVEL >= LOG_LEVEL_INFO + /* + * 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. + */ + mov x5, x0 + mov x6, x1 + + /* Ensure the console is initialized */ + bl plat_crash_console_init + + /* Check if the console is initialized */ + cbz x0, _assert_loop + + /* The console is initialized */ + adr x4, assert_msg1 + bl asm_print_str + mov x4, x5 + bl asm_print_str + adr x4, assert_msg2 + bl asm_print_str + + /* Check if line number higher than max permitted */ + tst x6, #~0xffff + b.ne _assert_loop + mov x4, x6 + asm_print_line_dec + bl plat_crash_console_flush +_assert_loop: +#endif /* LOG_LEVEL >= LOG_LEVEL_INFO */ + no_ret plat_panic_handler +endfunc asm_assert +#endif /* ENABLE_ASSERTIONS */ + +/* + * This function prints a string from address in x4. + * In: x4 = pointer to string. + * Clobber: x30, x0, x1, x2, x3 + */ +func asm_print_str + mov x3, x30 +1: + ldrb w0, [x4], #0x1 + cbz x0, 2f + bl plat_crash_console_putc + b 1b +2: + ret x3 +endfunc asm_print_str + +/* + * This function prints a hexadecimal number in x4. + * In: x4 = the hexadecimal to print. + * Clobber: x30, x0 - x3, x5 + */ +func asm_print_hex + mov x5, #64 /* No of bits to convert to ascii */ + + /* Convert to ascii number of bits in x5 */ +asm_print_hex_bits: + mov x3, x30 +1: + sub x5, x5, #4 + lsrv x0, x4, x5 + and x0, x0, #0xf + cmp x0, #0xA + b.lo 2f + /* Add by 0x27 in addition to ASCII_OFFSET_NUM + * to get ascii for characters 'a - f'. + */ + add x0, x0, #0x27 +2: + add x0, x0, #ASCII_OFFSET_NUM + bl plat_crash_console_putc + cbnz x5, 1b + ret x3 +endfunc asm_print_hex + +/* + * Helper function to print newline to console + * Clobber: x0 + */ +func asm_print_newline + mov x0, '\n' + b plat_crash_console_putc +endfunc asm_print_newline + + /*********************************************************** + * The common implementation of do_panic for all BL stages + ***********************************************************/ + +.section .rodata.panic_str, "aS" + panic_msg: .asciz "PANIC at PC : 0x" + +/* --------------------------------------------------------------------------- + * do_panic assumes that it is invoked from a C Runtime Environment ie a + * valid stack exists. This call will not return. + * Clobber list : if CRASH_REPORTING is not enabled then x30, x0 - x6 + * --------------------------------------------------------------------------- + */ + +/* This is for the non el3 BL stages to compile through */ + .weak el3_panic + .weak elx_panic + +func do_panic +#if CRASH_REPORTING + str x0, [sp, #-0x10]! + mrs x0, currentel + ubfx x0, x0, #MODE_EL_SHIFT, #MODE_EL_WIDTH + cmp x0, #MODE_EL3 +#if !HANDLE_EA_EL3_FIRST_NS + ldr x0, [sp], #0x10 + b.eq el3_panic +#else + b.ne to_panic_common + + /* Check EL the exception taken from */ + mrs x0, spsr_el3 + ubfx x0, x0, #SPSR_EL_SHIFT, #SPSR_EL_WIDTH + cmp x0, #MODE_EL3 + b.ne elx_panic + ldr x0, [sp], #0x10 + b el3_panic + +to_panic_common: + ldr x0, [sp], #0x10 +#endif /* HANDLE_EA_EL3_FIRST_NS */ +#endif /* CRASH_REPORTING */ + +panic_common: +/* + * el3_panic will be redefined by the BL31 + * crash reporting mechanism (if enabled) + */ +el3_panic: + mov x6, x30 + bl plat_crash_console_init + + /* Check if the console is initialized */ + cbz x0, _panic_handler + + /* The console is initialized */ + adr x4, panic_msg + bl asm_print_str + mov x4, x6 + + /* The panic location is lr -4 */ + sub x4, x4, #4 + bl asm_print_hex + + /* Print new line */ + bl asm_print_newline + + bl plat_crash_console_flush + +_panic_handler: + /* Pass to plat_panic_handler the address from where el3_panic was + * called, not the address of the call from el3_panic. */ + mov x30, x6 + b plat_panic_handler +endfunc do_panic |