old-cross-binutils/gdb/nat/ppc-linux.c
Yao Qi cdf436294f Detect 64-bit-ness in PowerPC Book III-E
This patch is to teach both GDB and GDBServer to detect 64-bit inferior
correctly.  We find a problem that GDBServer is unable to detect on a
e5500 core processor.  Current GDBServer assumes that MSR is a 64-bit
register, but MSR is a 32-bit register in Book III-E.  This patch is
to fix this problem by checking the right bit in MSR, in order to handle
both Book III-S and Book III-E.  In order to detect Book III-S and
Book III-E, we check the PPC_FEATURE_BOOKE from the host's HWCAP (by
getauxval on glibc >= 2.16.  If getauxval doesn't exist, we implement
the fallback by parsing /proc/self/auxv), because it should an invariant
on the same machine cross different processes.

In order to share code, I add nat/ppc-linux.c for both GDB and
GDBserver side.

gdb:

2015-01-14  Yao Qi  <yao@codesourcery.com>

	* Makefile.in (ppc-linux.o): New rule.
	* config/powerpc/ppc64-linux.mh (NATDEPFILES): Add ppc-linux.o.
	* configure.ac: AC_CHECK_FUNCS(getauxval).
	* config.in: Re-generated.
	* configure: Re-generated.
	* nat/ppc-linux.h [__powerpc64__] (ppc64_64bit_inferior_p):
	Declare.
	* nat/ppc-linux.c: New file.
	* ppc-linux-nat.c (ppc_linux_target_wordsize) [__powerpc64__]:
	Call ppc64_64bit_inferior_p.

gdb/gdbserver:

2015-01-14  Yao Qi  <yao@codesourcery.com>

	* Makefile.in (SFILES): Add nat/ppc-linux.c.
	(ppc-linux.o): New rule.
	* configure.srv (powerpc*-*-linux*): Add ppc-linux.o.
	* configure.ac: AC_CHECK_FUNCS(getauxval).
	* config.in: Re-generated.
	* configure: Re-generated.
	* linux-ppc-low.c (ppc_arch_setup) [__powerpc64__]: Call
	ppc64_64bit_inferior_p
2015-01-14 22:28:27 +08:00

75 lines
1.9 KiB
C

/*Copyright (C) 2015 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 "common-defs.h"
#include "ppc-linux.h"
#include <elf.h>
#ifdef HAVE_GETAUXVAL
#include <sys/auxv.h>
#endif
#ifdef __powerpc64__
/* Get the HWCAP from the process of GDB or GDBserver. If success,
save it in *VALP. */
static void
ppc64_host_hwcap (unsigned long *valp)
{
#ifdef HAVE_GETAUXVAL
*valp = getauxval (AT_HWCAP);
#else
unsigned long data[2];
FILE *f = fopen ("/proc/self/auxv", "r");
if (f == NULL)
return;
while (fread (data, sizeof (data), 1, f) > 0)
{
if (data[0] == AT_HWCAP)
{
*valp = data[1];
break;
}
}
fclose (f);
#endif /* HAVE_GETAUXVAL */
}
int
ppc64_64bit_inferior_p (long msr)
{
unsigned long ppc_host_hwcap = 0;
/* Get host's HWCAP to check whether the machine is Book E. */
ppc64_host_hwcap (&ppc_host_hwcap);
/* We actually have a 64-bit inferior only if the certain bit of the
MSR is set. The PowerISA Book III-S MSR is different from the
PowerISA Book III-E MSR. The Book III-S MSR is 64 bits wide, and
its MSR[SF] is the bit 0 of a 64-bit value. Book III-E MSR is 32
bits wide, and its MSR[CM] is the bit 0 of a 32-bit value. */
if (ppc_host_hwcap & PPC_FEATURE_BOOKE)
return msr & 0x80000000;
else
return msr < 0;
}
#endif