diff options
Diffstat (limited to 'arch/arm/lib')
| -rw-r--r-- | arch/arm/lib/Makefile | 2 | ||||
| -rw-r--r-- | arch/arm/lib/debug.S | 136 |
2 files changed, 138 insertions, 0 deletions
diff --git a/arch/arm/lib/Makefile b/arch/arm/lib/Makefile index 1ef240047f..d74e4b8415 100644 --- a/arch/arm/lib/Makefile +++ b/arch/arm/lib/Makefile @@ -48,6 +48,8 @@ ifndef CONFIG_ARM64 obj-y += cache-cp15.o endif +obj-$(CONFIG_DEBUG_LL) += debug.o + # For EABI conformant tool chains, provide eabi_compat() ifneq (,$(findstring -mabi=aapcs-linux,$(PLATFORM_CPPFLAGS))) extra-y += eabi_compat.o diff --git a/arch/arm/lib/debug.S b/arch/arm/lib/debug.S new file mode 100644 index 0000000000..760ba74a3c --- /dev/null +++ b/arch/arm/lib/debug.S @@ -0,0 +1,136 @@ +/* + * linux/arch/arm/kernel/debug.S + * + * Copyright (C) 1994-1999 Russell King + * + * SPDX-License-Identifier: GPL-2.0+ + * + * 32-bit debugging code + */ +#include <linux/linkage.h> +#include <asm/assembler.h> + + .text + +/* + * Some debugging routines (useful if you've got MM problems and + * printk isn't working). For DEBUGGING ONLY!!! Do not leave + * references to these in a production kernel! + */ + +#if !defined(CONFIG_DEBUG_SEMIHOSTING) +#include CONFIG_DEBUG_LL_INCLUDE +#endif + +#ifdef CONFIG_MMU + .macro addruart_current, rx, tmp1, tmp2 + addruart \tmp1, \tmp2, \rx + mrc p15, 0, \rx, c1, c0 + tst \rx, #1 + moveq \rx, \tmp1 + movne \rx, \tmp2 + .endm + +#else /* !CONFIG_MMU */ + .macro addruart_current, rx, tmp1, tmp2 + addruart \rx, \tmp1, \tmp2 + .endm + +#endif /* CONFIG_MMU */ + +/* + * Useful debugging routines + */ +ENTRY(printhex8) + mov r1, #8 + b printhex +ENDPROC(printhex8) + +ENTRY(printhex4) + mov r1, #4 + b printhex +ENDPROC(printhex4) + +ENTRY(printhex2) + mov r1, #2 +printhex: adr r2, hexbuf + add r3, r2, r1 + mov r1, #0 + strb r1, [r3] +1: and r1, r0, #15 + mov r0, r0, lsr #4 + cmp r1, #10 + addlt r1, r1, #'0' + addge r1, r1, #'a' - 10 + strb r1, [r3, #-1]! + teq r3, r2 + bne 1b + mov r0, r2 + b printascii +ENDPROC(printhex2) + +hexbuf: .space 16 + + .ltorg + +#ifndef CONFIG_DEBUG_SEMIHOSTING + +ENTRY(printascii) + addruart_current r3, r1, r2 + b 2f +1: waituart r2, r3 + senduart r1, r3 + busyuart r2, r3 + teq r1, #'\n' + moveq r1, #'\r' + beq 1b +2: teq r0, #0 + ldrneb r1, [r0], #1 + teqne r1, #0 + bne 1b + mov pc, lr +ENDPROC(printascii) + +ENTRY(printch) + addruart_current r3, r1, r2 + mov r1, r0 + mov r0, #0 + b 1b +ENDPROC(printch) + +#ifdef CONFIG_MMU +ENTRY(debug_ll_addr) + addruart r2, r3, ip + str r2, [r0] + str r3, [r1] + mov pc, lr +ENDPROC(debug_ll_addr) +#endif + +#else + +ENTRY(printascii) + mov r1, r0 + mov r0, #0x04 @ SYS_WRITE0 + ARM( svc #0x123456 ) + THUMB( svc #0xab ) + mov pc, lr +ENDPROC(printascii) + +ENTRY(printch) + adr r1, hexbuf + strb r0, [r1] + mov r0, #0x03 @ SYS_WRITEC + ARM( svc #0x123456 ) + THUMB( svc #0xab ) + mov pc, lr +ENDPROC(printch) + +ENTRY(debug_ll_addr) + mov r2, #0 + str r2, [r0] + str r2, [r1] + mov pc, lr +ENDPROC(debug_ll_addr) + +#endif |
