linux-sg2042/arch/nios2/kernel/kgdb.c

172 lines
5.1 KiB
C

/*
* 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 },
};