binutils-gdb/gdb/gdbserver/linux-nios2-low.c
Joel Brobecker 61baf725ec update copyright year range in GDB files
This applies the second part of GDB's End of Year Procedure, which
updates the copyright year range in all of GDB's files.

gdb/ChangeLog:

        Update copyright year range in all GDB files.
2017-01-01 10:52:34 +04:00

260 lines
6.4 KiB
C

/* GNU/Linux/Nios II specific low level interface, for the remote server for
GDB.
Copyright (C) 2008-2017 Free Software Foundation, Inc.
Contributed by Mentor Graphics, Inc.
This file is part of GDB.
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 3 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 "server.h"
#include "linux-low.h"
#include "elf/common.h"
#include "nat/gdb_ptrace.h"
#include <endian.h>
#include "gdb_proc_service.h"
#include <asm/ptrace.h>
#ifndef PTRACE_GET_THREAD_AREA
#define PTRACE_GET_THREAD_AREA 25
#endif
/* The following definition must agree with the number of registers
defined in "struct user_regs" in GLIBC
(sysdeps/unix/sysv/linux/nios2/sys/user.h), and also with
NIOS2_NUM_REGS in GDB proper. */
#define nios2_num_regs 49
/* Defined in auto-generated file nios2-linux.c. */
void init_registers_nios2_linux (void);
extern const struct target_desc *tdesc_nios2_linux;
/* This union is used to convert between int and byte buffer
representations of register contents. */
union nios2_register
{
unsigned char buf[4];
int reg32;
};
/* Return the ptrace ``address'' of register REGNO. */
static int nios2_regmap[] = {
-1, 1, 2, 3, 4, 5, 6, 7,
8, 9, 10, 11, 12, 13, 14, 15,
16, 17, 18, 19, 20, 21, 22, 23,
24, 25, 26, 27, 28, 29, 30, 31,
32, 33, 34, 35, 36, 37, 38, 39,
40, 41, 42, 43, 44, 45, 46, 47,
48,
0
};
/* Implement the arch_setup linux_target_ops method. */
static void
nios2_arch_setup (void)
{
current_process ()->tdesc = tdesc_nios2_linux;
}
/* Implement the cannot_fetch_register linux_target_ops method. */
static int
nios2_cannot_fetch_register (int regno)
{
if (nios2_regmap[regno] == -1)
return 1;
return 0;
}
/* Implement the cannot_store_register linux_target_ops method. */
static int
nios2_cannot_store_register (int regno)
{
if (nios2_regmap[regno] == -1)
return 1;
return 0;
}
/* Breakpoint support. Also see comments on nios2_breakpoint_from_pc
in nios2-tdep.c. */
#if defined(__nios2_arch__) && __nios2_arch__ == 2
#define NIOS2_BREAKPOINT 0xb7fd0020
#define CDX_BREAKPOINT 0xd7c9
#else
#define NIOS2_BREAKPOINT 0x003b6ffa
#endif
/* We only register the 4-byte breakpoint, even on R2 targets which also
support 2-byte breakpoints. Since there is no supports_z_point_type
function provided, gdbserver never inserts software breakpoints itself
and instead relies on GDB to insert the breakpoint of the correct length
via a memory write. */
static const unsigned int nios2_breakpoint = NIOS2_BREAKPOINT;
#define nios2_breakpoint_len 4
/* Implementation of linux_target_ops method "sw_breakpoint_from_kind". */
static const gdb_byte *
nios2_sw_breakpoint_from_kind (int kind, int *size)
{
*size = nios2_breakpoint_len;
return (const gdb_byte *) &nios2_breakpoint;
}
/* Implement the breakpoint_at linux_target_ops method. */
static int
nios2_breakpoint_at (CORE_ADDR where)
{
unsigned int insn;
/* For R2, first check for the 2-byte CDX trap.n breakpoint encoding. */
#if defined(__nios2_arch__) && __nios2_arch__ == 2
(*the_target->read_memory) (where, (unsigned char *) &insn, 2);
if (insn == CDX_BREAKPOINT)
return 1;
#endif
(*the_target->read_memory) (where, (unsigned char *) &insn, 4);
if (insn == nios2_breakpoint)
return 1;
return 0;
}
/* Fetch the thread-local storage pointer for libthread_db. */
ps_err_e
ps_get_thread_area (struct ps_prochandle *ph,
lwpid_t lwpid, int idx, void **base)
{
if (ptrace (PTRACE_GET_THREAD_AREA, lwpid, NULL, base) != 0)
return PS_ERR;
/* IDX is the bias from the thread pointer to the beginning of the
thread descriptor. It has to be subtracted due to implementation
quirks in libthread_db. */
*base = (void *) ((char *) *base - idx);
return PS_OK;
}
/* Helper functions to collect/supply a single register REGNO. */
static void
nios2_collect_register (struct regcache *regcache, int regno,
union nios2_register *reg)
{
union nios2_register tmp_reg;
collect_register (regcache, regno, &tmp_reg.reg32);
reg->reg32 = tmp_reg.reg32;
}
static void
nios2_supply_register (struct regcache *regcache, int regno,
const union nios2_register *reg)
{
supply_register (regcache, regno, reg->buf);
}
/* We have only a single register set on Nios II. */
static void
nios2_fill_gregset (struct regcache *regcache, void *buf)
{
union nios2_register *regset = (union nios2_register *) buf;
int i;
for (i = 1; i < nios2_num_regs; i++)
nios2_collect_register (regcache, i, regset + i);
}
static void
nios2_store_gregset (struct regcache *regcache, const void *buf)
{
const union nios2_register *regset = (union nios2_register *) buf;
int i;
for (i = 0; i < nios2_num_regs; i++)
nios2_supply_register (regcache, i, regset + i);
}
static struct regset_info nios2_regsets[] =
{
{ PTRACE_GETREGSET, PTRACE_SETREGSET, NT_PRSTATUS,
nios2_num_regs * 4, GENERAL_REGS,
nios2_fill_gregset, nios2_store_gregset },
NULL_REGSET
};
static struct regsets_info nios2_regsets_info =
{
nios2_regsets, /* regsets */
0, /* num_regsets */
NULL, /* disabled_regsets */
};
static struct usrregs_info nios2_usrregs_info =
{
nios2_num_regs,
nios2_regmap,
};
static struct regs_info regs_info =
{
NULL, /* regset_bitmap */
&nios2_usrregs_info,
&nios2_regsets_info
};
static const struct regs_info *
nios2_regs_info (void)
{
return &regs_info;
}
struct linux_target_ops the_low_target =
{
nios2_arch_setup,
nios2_regs_info,
nios2_cannot_fetch_register,
nios2_cannot_store_register,
NULL,
linux_get_pc_32bit,
linux_set_pc_32bit,
NULL, /* breakpoint_kind_from_pc */
nios2_sw_breakpoint_from_kind,
NULL, /* get_next_pcs */
0,
nios2_breakpoint_at,
};
void
initialize_low_arch (void)
{
init_registers_nios2_linux ();
initialize_regsets_info (&nios2_regsets_info);
}