From 1cfe9fa012da6c70402b5c2787414fd47fafb65f Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 1 Sep 2014 11:06:32 +0900 Subject: arm: debug: import debug files from Linux 3.16 U-Boot does not have arch/arm/kernel, include/uapi directories, This commit copies files as follows: Location in Linux -> Location in U-Boot arch/arm/kernel/debug.S -> arch/arm/lib/debug.S arch/arm/include/debug/8250.S -> arch/arm/include/debug/8250.S include/uapi/linux/serial_reg.h -> include/linux/serial_reg.h Signed-off-by: Masahiro Yamada --- arch/arm/lib/debug.S | 138 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 138 insertions(+) create mode 100644 arch/arm/lib/debug.S (limited to 'arch/arm/lib') diff --git a/arch/arm/lib/debug.S b/arch/arm/lib/debug.S new file mode 100644 index 0000000000..14f7c3b146 --- /dev/null +++ b/arch/arm/lib/debug.S @@ -0,0 +1,138 @@ +/* + * linux/arch/arm/kernel/debug.S + * + * Copyright (C) 1994-1999 Russell King + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * 32-bit debugging code + */ +#include +#include + + .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 + .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 -- cgit v1.2.1 From 93456512005081d667811a223b8022c013d4d2d7 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 1 Sep 2014 11:06:33 +0900 Subject: arm: debug: replace license blocks with SPDX Signed-off-by: Masahiro Yamada --- arch/arm/lib/debug.S | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'arch/arm/lib') diff --git a/arch/arm/lib/debug.S b/arch/arm/lib/debug.S index 14f7c3b146..ddee7c09c8 100644 --- a/arch/arm/lib/debug.S +++ b/arch/arm/lib/debug.S @@ -3,9 +3,7 @@ * * Copyright (C) 1994-1999 Russell King * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. + * SPDX-License-Identifier: GPL-2.0+ * * 32-bit debugging code */ -- cgit v1.2.1 From 51b17d494656c6c0db230e0a5ba9c733a96309bf Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 1 Sep 2014 11:06:34 +0900 Subject: arm: debug: add Kconfig entries for lowlevel debug We have not had a good method to debug the early boot stage such as lowlevel_init function. I guess developers generally use dedicated debuggers for that, but it is difficult in some cases. (For example, my debugger cannot connect to the ARM processor when it is in the secure state. It sometimes happens when I need to debug the early boot stage on ARM SoCs with secure extension.) The low level debug feature in Linux would be also helpful for U-boot when we are stucking in nasty problems where the console is not available yet. You have to enable CONFIG_DEBUG_LL to use this feature. For now, only 8250-compatible UART devices are supported. You can add a header file under arch/arm/include/debug/ directory to support your UART device if necessary. Signed-off-by: Masahiro Yamada --- arch/arm/lib/Makefile | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/arm/lib') 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 -- cgit v1.2.1 From b81fa615df129f29d343abb382392ca4ef17bdc6 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 1 Sep 2014 11:06:35 +0900 Subject: arm: debug: adjust for U-Boot Because CONFIG_MMU is never defined in U-Boot, the non-MMU code in debug.S is always used. Unfortunately, the number of arguments of the addruart macro in Linux is different between MMU and non-MMU. This causes a build error when importing some debug macros using the third argument. (For ex. arch/arm/include/debug/exynos.S) Pass the third argument to the non-MMU addruart to avoid such a problem. Signed-off-by: Masahiro Yamada Tested-by: Przemyslaw Marczak --- arch/arm/lib/debug.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/arm/lib') diff --git a/arch/arm/lib/debug.S b/arch/arm/lib/debug.S index ddee7c09c8..760ba74a3c 100644 --- a/arch/arm/lib/debug.S +++ b/arch/arm/lib/debug.S @@ -33,7 +33,7 @@ #else /* !CONFIG_MMU */ .macro addruart_current, rx, tmp1, tmp2 - addruart \rx, \tmp1 + addruart \rx, \tmp1, \tmp2 .endm #endif /* CONFIG_MMU */ -- cgit v1.2.1