qemu/target/ppc/gdbstub.c
Michael Matz a2f04333a3 ppc: Fix size of ppc64 xer register
The normal gdb definition of the XER registers is only 32 bit,
and that's what the current version of power64-core.xml also
says (seems copied from gdb's).  But qemu's idea of the XER register
is target_ulong (in CPUPPCState, ppc_gdb_register_len and
ppc_cpu_gdb_read_register)

That mismatch leads to the following message when attaching
with gdb:

  Truncated register 32 in remote 'g' packet

(and following on that qemu stops responding).  The simple fix is
to say the truth in the .xml file.  But the better fix is to
actually make it 32bit on the wire, as old gdbs don't support
XML files for describing registers.  Also the XER state in qemu
doesn't seem to use the high 32 bits, so sending it off to gdb
doesn't seem worthwhile.

Signed-off-by: Michael Matz <matz@suse.de>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-04-27 18:05:22 +10:00

322 lines
8.2 KiB
C

/*
* PowerPC gdb server stub
*
* Copyright (c) 2003-2005 Fabrice Bellard
* Copyright (c) 2013 SUSE LINUX Products GmbH
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "qemu/osdep.h"
#include "qemu-common.h"
#include "cpu.h"
#include "exec/gdbstub.h"
static int ppc_gdb_register_len_apple(int n)
{
switch (n) {
case 0 ... 31:
/* gprs */
return 8;
case 32 ... 63:
/* fprs */
return 8;
case 64 ... 95:
return 16;
case 64+32: /* nip */
case 65+32: /* msr */
case 67+32: /* lr */
case 68+32: /* ctr */
case 70+32: /* fpscr */
return 8;
case 66+32: /* cr */
case 69+32: /* xer */
return 4;
default:
return 0;
}
}
static int ppc_gdb_register_len(int n)
{
switch (n) {
case 0 ... 31:
/* gprs */
return sizeof(target_ulong);
case 32 ... 63:
/* fprs */
if (gdb_has_xml) {
return 0;
}
return 8;
case 66:
/* cr */
case 69:
/* xer */
return 4;
case 64:
/* nip */
case 65:
/* msr */
case 67:
/* lr */
case 68:
/* ctr */
return sizeof(target_ulong);
case 70:
/* fpscr */
if (gdb_has_xml) {
return 0;
}
return sizeof(target_ulong);
default:
return 0;
}
}
/* We need to present the registers to gdb in the "current" memory ordering.
For user-only mode we get this for free; TARGET_WORDS_BIGENDIAN is set to
the proper ordering for the binary, and cannot be changed.
For system mode, TARGET_WORDS_BIGENDIAN is always set, and we must check
the current mode of the chip to see if we're running in little-endian. */
void ppc_maybe_bswap_register(CPUPPCState *env, uint8_t *mem_buf, int len)
{
#ifndef CONFIG_USER_ONLY
if (!msr_le) {
/* do nothing */
} else if (len == 4) {
bswap32s((uint32_t *)mem_buf);
} else if (len == 8) {
bswap64s((uint64_t *)mem_buf);
} else {
g_assert_not_reached();
}
#endif
}
/* Old gdb always expects FP registers. Newer (xml-aware) gdb only
* expects whatever the target description contains. Due to a
* historical mishap the FP registers appear in between core integer
* regs and PC, MSR, CR, and so forth. We hack round this by giving the
* FP regs zero size when talking to a newer gdb.
*/
int ppc_cpu_gdb_read_register(CPUState *cs, uint8_t *mem_buf, int n)
{
PowerPCCPU *cpu = POWERPC_CPU(cs);
CPUPPCState *env = &cpu->env;
int r = ppc_gdb_register_len(n);
if (!r) {
return r;
}
if (n < 32) {
/* gprs */
gdb_get_regl(mem_buf, env->gpr[n]);
} else if (n < 64) {
/* fprs */
stfq_p(mem_buf, env->fpr[n-32]);
} else {
switch (n) {
case 64:
gdb_get_regl(mem_buf, env->nip);
break;
case 65:
gdb_get_regl(mem_buf, env->msr);
break;
case 66:
{
uint32_t cr = 0;
int i;
for (i = 0; i < 8; i++) {
cr |= env->crf[i] << (32 - ((i + 1) * 4));
}
gdb_get_reg32(mem_buf, cr);
break;
}
case 67:
gdb_get_regl(mem_buf, env->lr);
break;
case 68:
gdb_get_regl(mem_buf, env->ctr);
break;
case 69:
gdb_get_reg32(mem_buf, env->xer);
break;
case 70:
gdb_get_reg32(mem_buf, env->fpscr);
break;
}
}
ppc_maybe_bswap_register(env, mem_buf, r);
return r;
}
int ppc_cpu_gdb_read_register_apple(CPUState *cs, uint8_t *mem_buf, int n)
{
PowerPCCPU *cpu = POWERPC_CPU(cs);
CPUPPCState *env = &cpu->env;
int r = ppc_gdb_register_len_apple(n);
if (!r) {
return r;
}
if (n < 32) {
/* gprs */
gdb_get_reg64(mem_buf, env->gpr[n]);
} else if (n < 64) {
/* fprs */
stfq_p(mem_buf, env->fpr[n-32]);
} else if (n < 96) {
/* Altivec */
stq_p(mem_buf, n - 64);
stq_p(mem_buf + 8, 0);
} else {
switch (n) {
case 64 + 32:
gdb_get_reg64(mem_buf, env->nip);
break;
case 65 + 32:
gdb_get_reg64(mem_buf, env->msr);
break;
case 66 + 32:
{
uint32_t cr = 0;
int i;
for (i = 0; i < 8; i++) {
cr |= env->crf[i] << (32 - ((i + 1) * 4));
}
gdb_get_reg32(mem_buf, cr);
break;
}
case 67 + 32:
gdb_get_reg64(mem_buf, env->lr);
break;
case 68 + 32:
gdb_get_reg64(mem_buf, env->ctr);
break;
case 69 + 32:
gdb_get_reg32(mem_buf, env->xer);
break;
case 70 + 32:
gdb_get_reg64(mem_buf, env->fpscr);
break;
}
}
ppc_maybe_bswap_register(env, mem_buf, r);
return r;
}
int ppc_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n)
{
PowerPCCPU *cpu = POWERPC_CPU(cs);
CPUPPCState *env = &cpu->env;
int r = ppc_gdb_register_len(n);
if (!r) {
return r;
}
ppc_maybe_bswap_register(env, mem_buf, r);
if (n < 32) {
/* gprs */
env->gpr[n] = ldtul_p(mem_buf);
} else if (n < 64) {
/* fprs */
env->fpr[n-32] = ldfq_p(mem_buf);
} else {
switch (n) {
case 64:
env->nip = ldtul_p(mem_buf);
break;
case 65:
ppc_store_msr(env, ldtul_p(mem_buf));
break;
case 66:
{
uint32_t cr = ldl_p(mem_buf);
int i;
for (i = 0; i < 8; i++) {
env->crf[i] = (cr >> (32 - ((i + 1) * 4))) & 0xF;
}
break;
}
case 67:
env->lr = ldtul_p(mem_buf);
break;
case 68:
env->ctr = ldtul_p(mem_buf);
break;
case 69:
env->xer = ldl_p(mem_buf);
break;
case 70:
/* fpscr */
store_fpscr(env, ldtul_p(mem_buf), 0xffffffff);
break;
}
}
return r;
}
int ppc_cpu_gdb_write_register_apple(CPUState *cs, uint8_t *mem_buf, int n)
{
PowerPCCPU *cpu = POWERPC_CPU(cs);
CPUPPCState *env = &cpu->env;
int r = ppc_gdb_register_len_apple(n);
if (!r) {
return r;
}
ppc_maybe_bswap_register(env, mem_buf, r);
if (n < 32) {
/* gprs */
env->gpr[n] = ldq_p(mem_buf);
} else if (n < 64) {
/* fprs */
env->fpr[n-32] = ldfq_p(mem_buf);
} else {
switch (n) {
case 64 + 32:
env->nip = ldq_p(mem_buf);
break;
case 65 + 32:
ppc_store_msr(env, ldq_p(mem_buf));
break;
case 66 + 32:
{
uint32_t cr = ldl_p(mem_buf);
int i;
for (i = 0; i < 8; i++) {
env->crf[i] = (cr >> (32 - ((i + 1) * 4))) & 0xF;
}
break;
}
case 67 + 32:
env->lr = ldq_p(mem_buf);
break;
case 68 + 32:
env->ctr = ldq_p(mem_buf);
break;
case 69 + 32:
env->xer = ldl_p(mem_buf);
break;
case 70 + 32:
/* fpscr */
store_fpscr(env, ldq_p(mem_buf), 0xffffffff);
break;
}
}
return r;
}