Commit d16d2be1 authored by Ley Foon Tan's avatar Ley Foon Tan
Browse files

nios2: add kgdb support 



Signed-off-by: default avatarLey Foon Tan <lftan@altera.com>
parent 08c283cc

arch/nios2/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -8,6 +8,7 @@ config NIOS2 
	select GENERIC_IRQ_PROBE

	select GENERIC_IRQ_SHOW

	select HAVE_ARCH_TRACEHOOK

	select HAVE_ARCH_KGDB

	select IRQ_DOMAIN

	select MODULES_USE_ELF_RELA

	select OF

arch/nios2/include/asm/kgdb.h

0 → 100644
+93 −0
Original line number Diff line number Diff line 
/*

 * Copyright (C) 2015 Altera Corporation

 * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>

 *

 * Based on the code posted by Kazuyasu on the Altera Forum at:

 * http://www.alteraforum.com/forum/showpost.php?p=77003&postcount=20

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 2 of the License, or

 * (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program.  If not, see <http://www.gnu.org/licenses/>.

 *

 */



#ifndef _ASM_NIOS2_KGDB_H

#define _ASM_NIOS2_KGDB_H



#define CACHE_FLUSH_IS_SAFE	1

#define BUFMAX			2048



enum regnames {

	GDB_R0 = 0,

	GDB_AT,

	GDB_R2,

	GDB_R3,

	GDB_R4,

	GDB_R5,

	GDB_R6,

	GDB_R7,

	GDB_R8,

	GDB_R9,

	GDB_R10,

	GDB_R11,

	GDB_R12,

	GDB_R13,

	GDB_R14,

	GDB_R15,

	GDB_R16,

	GDB_R17,

	GDB_R18,

	GDB_R19,

	GDB_R20,

	GDB_R21,

	GDB_R22,

	GDB_R23,

	GDB_ET,

	GDB_BT,

	GDB_GP,

	GDB_SP,

	GDB_FP,

	GDB_EA,

	GDB_BA,

	GDB_RA,

	GDB_PC,

	GDB_STATUS,

	GDB_ESTATUS,

	GDB_BSTATUS,

	GDB_IENABLE,

	GDB_IPENDING,

	GDB_CPUID,

	GDB_CTL6,

	GDB_EXCEPTION,

	GDB_PTEADDR,

	GDB_TLBACC,

	GDB_TLBMISC,

	GDB_ECCINJ,

	GDB_BADADDR,

	GDB_CONFIG,

	GDB_MPUBASE,

	GDB_MPUACC,

	/* do not change the last entry or anything below! */

	GDB_NUMREGBYTES		/* number of registers */

};



#define GDB_SIZEOF_REG		sizeof(u32)

#define DBG_MAX_REG_NUM	(49)

#define NUMREGBYTES		(DBG_MAX_REG_NUM * sizeof(GDB_SIZEOF_REG))



#define BREAK_INSTR_SIZE	4

static inline void arch_kgdb_breakpoint(void)

{

	__asm__ __volatile__("trap 30\n");

}



#endif /* _ASM_NIOS2_KGDB_H */

arch/nios2/kernel/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -21,5 +21,6 @@ obj-y += time.o 
obj-y	+= traps.o



obj-$(CONFIG_EARLY_PRINTK)		+= early_printk.o

obj-$(CONFIG_KGDB)			+= kgdb.o

obj-$(CONFIG_MODULES)			+= module.o

obj-$(CONFIG_NIOS2_ALIGNMENT_TRAP)	+= misaligned.o

arch/nios2/kernel/entry.S

+11 −1
Original line number Diff line number Diff line
@@ -121,7 +121,11 @@ trap_table: 
	.word	instruction_trap	/* 27 */

	.word	instruction_trap	/* 28 */

	.word	instruction_trap	/* 29 */

#ifdef CONFIG_KGDB

	.word	handle_kgdb_breakpoint	/* 30 KGDB breakpoint */

#else

	.word	instruction_trap		/* 30 */

#endif

	.word	handle_breakpoint	/* 31 */



.text
@@ -445,6 +449,12 @@ handle_diverror: 
	call	handle_diverror_c

	br	ret_from_exception



#ifdef CONFIG_KGDB

handle_kgdb_breakpoint:

	call	kgdb_breakpoint_c

	br	ret_from_exception

#endif



/*

 * Beware - when entering resume, prev (the current task) is

 * in r4, next (the new task) is in r5, don't change these

arch/nios2/kernel/kgdb.c

0 → 100644
+171 −0
Original line number Diff line number Diff line 
/*

 * Nios2 KGDB support

 *

 * Copyright (C) 2015 Altera Corporation

 * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>

 *

 * Based on the code posted by Kazuyasu on the Altera Forum at:

 * http://www.alteraforum.com/forum/showpost.php?p=77003&postcount=20

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 2 of the License, or

 * (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program.  If not, see <http://www.gnu.org/licenses/>.

 *

 */

#include <linux/ptrace.h>

#include <linux/kgdb.h>

#include <linux/kdebug.h>

#include <linux/io.h>



static int wait_for_remote_debugger;



struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] =

{

	{ "zero", GDB_SIZEOF_REG, -1 },

	{ "at", GDB_SIZEOF_REG, offsetof(struct pt_regs, r1) },

	{ "r2", GDB_SIZEOF_REG, offsetof(struct pt_regs, r2) },

	{ "r3", GDB_SIZEOF_REG, offsetof(struct pt_regs, r3) },

	{ "r4", GDB_SIZEOF_REG, offsetof(struct pt_regs, r4) },

	{ "r5", GDB_SIZEOF_REG, offsetof(struct pt_regs, r5) },

	{ "r6", GDB_SIZEOF_REG, offsetof(struct pt_regs, r6) },

	{ "r7", GDB_SIZEOF_REG, offsetof(struct pt_regs, r7) },

	{ "r8", GDB_SIZEOF_REG, offsetof(struct pt_regs, r8) },

	{ "r9", GDB_SIZEOF_REG, offsetof(struct pt_regs, r9) },

	{ "r10", GDB_SIZEOF_REG, offsetof(struct pt_regs, r10) },

	{ "r11", GDB_SIZEOF_REG, offsetof(struct pt_regs, r11) },

	{ "r12", GDB_SIZEOF_REG, offsetof(struct pt_regs, r12) },

	{ "r13", GDB_SIZEOF_REG, offsetof(struct pt_regs, r13) },

	{ "r14", GDB_SIZEOF_REG, offsetof(struct pt_regs, r14) },

	{ "r15", GDB_SIZEOF_REG, offsetof(struct pt_regs, r15) },

	{ "r16", GDB_SIZEOF_REG, -1 },

	{ "r17", GDB_SIZEOF_REG, -1 },

	{ "r18", GDB_SIZEOF_REG, -1 },

	{ "r19", GDB_SIZEOF_REG, -1 },

	{ "r20", GDB_SIZEOF_REG, -1 },

	{ "r21", GDB_SIZEOF_REG, -1 },

	{ "r22", GDB_SIZEOF_REG, -1 },

	{ "r23", GDB_SIZEOF_REG, -1 },

	{ "et", GDB_SIZEOF_REG, -1 },

	{ "bt", GDB_SIZEOF_REG, -1 },

	{ "gp", GDB_SIZEOF_REG, offsetof(struct pt_regs, gp) },

	{ "sp", GDB_SIZEOF_REG, offsetof(struct pt_regs, sp) },

	{ "fp", GDB_SIZEOF_REG, offsetof(struct pt_regs, fp) },

	{ "ea", GDB_SIZEOF_REG, -1 },

	{ "ba", GDB_SIZEOF_REG, -1 },

	{ "ra", GDB_SIZEOF_REG, offsetof(struct pt_regs, ra) },

	{ "pc", GDB_SIZEOF_REG, offsetof(struct pt_regs, ea) },

	{ "status", GDB_SIZEOF_REG, -1 },

	{ "estatus", GDB_SIZEOF_REG, offsetof(struct pt_regs, estatus) },

	{ "bstatus", GDB_SIZEOF_REG, -1 },

	{ "ienable", GDB_SIZEOF_REG, -1 },

	{ "ipending", GDB_SIZEOF_REG, -1},

	{ "cpuid", GDB_SIZEOF_REG, -1 },

	{ "ctl6", GDB_SIZEOF_REG, -1 },

	{ "exception", GDB_SIZEOF_REG, -1 },

	{ "pteaddr", GDB_SIZEOF_REG, -1 },

	{ "tlbacc", GDB_SIZEOF_REG, -1 },

	{ "tlbmisc", GDB_SIZEOF_REG, -1 },

	{ "eccinj", GDB_SIZEOF_REG, -1 },

	{ "badaddr", GDB_SIZEOF_REG, -1 },

	{ "config", GDB_SIZEOF_REG, -1 },

	{ "mpubase", GDB_SIZEOF_REG, -1 },

	{ "mpuacc", GDB_SIZEOF_REG, -1 },

};



char *dbg_get_reg(int regno, void *mem, struct pt_regs *regs)

{

	if (regno >= DBG_MAX_REG_NUM || regno < 0)

		return NULL;



	if (dbg_reg_def[regno].offset != -1)

		memcpy(mem, (void *)regs + dbg_reg_def[regno].offset,

		       dbg_reg_def[regno].size);

	else

		memset(mem, 0, dbg_reg_def[regno].size);



	return dbg_reg_def[regno].name;

}



int dbg_set_reg(int regno, void *mem, struct pt_regs *regs)

{

	if (regno >= DBG_MAX_REG_NUM || regno < 0)

		return -EINVAL;



	if (dbg_reg_def[regno].offset != -1)

		memcpy((void *)regs + dbg_reg_def[regno].offset, mem,

		       dbg_reg_def[regno].size);



	return 0;

}



void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p)

{

	memset((char *)gdb_regs, 0, NUMREGBYTES);

	gdb_regs[GDB_SP] = p->thread.kregs->sp;

	gdb_regs[GDB_PC] = p->thread.kregs->ea;

}



void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc)

{

	regs->ea = pc;

}



int kgdb_arch_handle_exception(int vector, int signo, int err_code,

				char *remcom_in_buffer, char *remcom_out_buffer,

				struct pt_regs *regs)

{

	char *ptr;

	unsigned long addr;



	switch (remcom_in_buffer[0]) {

	case 's':

	case 'c':

		/* handle the optional parameters */

		ptr = &remcom_in_buffer[1];

		if (kgdb_hex2long(&ptr, &addr))

			regs->ea = addr;



		return 0;

	}



	return -1; /* this means that we do not want to exit from the handler */

}



asmlinkage void kgdb_breakpoint_c(struct pt_regs *regs)

{

	/*

	 * The breakpoint entry code has moved the PC on by 4 bytes, so we must

	 * move it back.  This could be done on the host but we do it here

	 */

	if (!wait_for_remote_debugger)

		regs->ea -= 4;

	else	/* pass the first trap 30 code */

		wait_for_remote_debugger = 0;



	kgdb_handle_exception(30, SIGTRAP, 0, regs);

}



int kgdb_arch_init(void)

{

	wait_for_remote_debugger = 1;

	return 0;

}



void kgdb_arch_exit(void)

{

	/* Nothing to do */

}



struct kgdb_arch arch_kgdb_ops = {

	/* Breakpoint instruction: trap 30 */

	.gdb_bpt_instr = { 0xba, 0x6f, 0x3b, 0x00 },

};