binutils-gdb/gdb/xtensa-linux-tdep.c
Max Filippov 37d9e06231 gdb: xtensa: handle privileged registers
xtensa GDB may be used with both bare-metal and linux-based
applications. In case of bare-metal application gdbserver is able to
provide information about all CPU registers: both unprivileged and
privileged. In case of linux-based application only a small subset of
privileged state is available. Currently xtensa GDB only expects
unprivileged registers in 'g' packets and it fails to communicate with
server that sends both privileged and unprivileged registers.

Allow bare-metal xtensa GDB to deal with both privileged and
unprivileged registers by initializing tdep->num_regs with the total
number of target CPU registers. Keep linux-based xtensa GDB
functionality as is by copying tdep->num_nopriv_regs to tdep->num_regs.

gdb/
2018-05-09  Max Filippov  <jcmvbkbc@gmail.com>

	* xtensa-linux-tdep.c (xtensa-tdep.h): New include.
	(xtensa_linux_init_abi): Limit tdep->num_regs by
	tdep->num_nopriv_regs.
	* xtensa-tdep.c (xtensa_derive_tdep): Calculate
	tdep->num_nopriv_regs and only copy it to tdep->num_regs if it's
	not initialized.
2018-05-09 09:30:06 -07:00

127 lines
3.6 KiB
C

/* Target-dependent code for GNU/Linux on Xtensa processors.
Copyright (C) 2007-2018 Free Software Foundation, 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 "defs.h"
#include "xtensa-tdep.h"
#include "osabi.h"
#include "linux-tdep.h"
#include "solib-svr4.h"
#include "symtab.h"
/* This enum represents the signals' numbers on the Xtensa
architecture. It just contains the signal definitions which are
different from the generic implementation.
It is derived from the file <arch/xtensa/include/uapi/asm/signal.h>,
from the Linux kernel tree. */
enum
{
XTENSA_LINUX_SIGRTMIN = 32,
XTENSA_LINUX_SIGRTMAX = 63,
};
/* Implementation of `gdbarch_gdb_signal_from_target', as defined in
gdbarch.h. */
static enum gdb_signal
xtensa_linux_gdb_signal_from_target (struct gdbarch *gdbarch,
int signal)
{
if (signal >= XTENSA_LINUX_SIGRTMIN && signal <= XTENSA_LINUX_SIGRTMAX)
{
int offset = signal - XTENSA_LINUX_SIGRTMIN;
if (offset == 0)
return GDB_SIGNAL_REALTIME_32;
else
return (enum gdb_signal) (offset - 1
+ (int) GDB_SIGNAL_REALTIME_33);
}
else if (signal > XTENSA_LINUX_SIGRTMAX)
return GDB_SIGNAL_UNKNOWN;
return linux_gdb_signal_from_target (gdbarch, signal);
}
/* Implementation of `gdbarch_gdb_signal_to_target', as defined in
gdbarch.h. */
static int
xtensa_linux_gdb_signal_to_target (struct gdbarch *gdbarch,
enum gdb_signal signal)
{
switch (signal)
{
/* GDB_SIGNAL_REALTIME_32 is not continuous in <gdb/signals.def>,
therefore we have to handle it here. */
case GDB_SIGNAL_REALTIME_32:
return XTENSA_LINUX_SIGRTMIN;
/* GDB_SIGNAL_REALTIME_64 is not valid on Xtensa. */
case GDB_SIGNAL_REALTIME_64:
return -1;
}
/* GDB_SIGNAL_REALTIME_33 to _63 are continuous.
Xtensa does not have _64. */
if (signal >= GDB_SIGNAL_REALTIME_33
&& signal <= GDB_SIGNAL_REALTIME_63)
{
int offset = signal - GDB_SIGNAL_REALTIME_33;
return XTENSA_LINUX_SIGRTMIN + 1 + offset;
}
return linux_gdb_signal_to_target (gdbarch, signal);
}
/* OS specific initialization of gdbarch. */
static void
xtensa_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
if (tdep->num_nopriv_regs < tdep->num_regs)
tdep->num_regs = tdep->num_nopriv_regs;
linux_init_abi (info, gdbarch);
set_solib_svr4_fetch_link_map_offsets
(gdbarch, svr4_ilp32_fetch_link_map_offsets);
set_gdbarch_gdb_signal_from_target (gdbarch,
xtensa_linux_gdb_signal_from_target);
set_gdbarch_gdb_signal_to_target (gdbarch,
xtensa_linux_gdb_signal_to_target);
/* Enable TLS support. */
set_gdbarch_fetch_tls_load_module_address (gdbarch,
svr4_fetch_objfile_link_map);
}
void
_initialize_xtensa_linux_tdep (void)
{
gdbarch_register_osabi (bfd_arch_xtensa, bfd_mach_xtensa, GDB_OSABI_LINUX,
xtensa_linux_init_abi);
}