qemu-e2k/target/ppc/gdbstub.c
Bruno Larsen (billionai) fe43ba9721 target/ppc: overhauled and moved logic of storing fpscr
Followed the suggested overhaul to store_fpscr logic, and moved it to
cpu.c where it can be accessed in !TCG builds.

The overhaul was suggested because storing a value to fpscr should
never raise an exception, so we could remove all the mess that happened
with POWERPC_EXCP_FP.

We also moved fpscr_set_rounding_mode into cpu.c as it could now be moved
there, and it is needed when a value for the fpscr is being stored
directly.

Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Bruno Larsen (billionai) <bruno.larsen@eldorado.org.br>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210527163522.23019-1-bruno.larsen@eldorado.org.br>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2021-06-03 18:10:31 +10:00

647 lines
16 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 2.1 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 "cpu.h"
#include "exec/gdbstub.h"
#include "internal.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, GByteArray *buf, int n)
{
PowerPCCPU *cpu = POWERPC_CPU(cs);
CPUPPCState *env = &cpu->env;
uint8_t *mem_buf;
int r = ppc_gdb_register_len(n);
if (!r) {
return r;
}
if (n < 32) {
/* gprs */
gdb_get_regl(buf, env->gpr[n]);
} else if (n < 64) {
/* fprs */
gdb_get_reg64(buf, *cpu_fpr_ptr(env, n - 32));
} else {
switch (n) {
case 64:
gdb_get_regl(buf, env->nip);
break;
case 65:
gdb_get_regl(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(buf, cr);
break;
}
case 67:
gdb_get_regl(buf, env->lr);
break;
case 68:
gdb_get_regl(buf, env->ctr);
break;
case 69:
gdb_get_reg32(buf, env->xer);
break;
case 70:
gdb_get_reg32(buf, env->fpscr);
break;
}
}
mem_buf = buf->data + buf->len - r;
ppc_maybe_bswap_register(env, mem_buf, r);
return r;
}
int ppc_cpu_gdb_read_register_apple(CPUState *cs, GByteArray *buf, int n)
{
PowerPCCPU *cpu = POWERPC_CPU(cs);
CPUPPCState *env = &cpu->env;
uint8_t *mem_buf;
int r = ppc_gdb_register_len_apple(n);
if (!r) {
return r;
}
if (n < 32) {
/* gprs */
gdb_get_reg64(buf, env->gpr[n]);
} else if (n < 64) {
/* fprs */
gdb_get_reg64(buf, *cpu_fpr_ptr(env, n - 32));
} else if (n < 96) {
/* Altivec */
gdb_get_reg64(buf, n - 64);
gdb_get_reg64(buf, 0);
} else {
switch (n) {
case 64 + 32:
gdb_get_reg64(buf, env->nip);
break;
case 65 + 32:
gdb_get_reg64(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(buf, cr);
break;
}
case 67 + 32:
gdb_get_reg64(buf, env->lr);
break;
case 68 + 32:
gdb_get_reg64(buf, env->ctr);
break;
case 69 + 32:
gdb_get_reg32(buf, env->xer);
break;
case 70 + 32:
gdb_get_reg64(buf, env->fpscr);
break;
}
}
mem_buf = buf->data + buf->len - r;
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 */
*cpu_fpr_ptr(env, n - 32) = ldq_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 */
ppc_store_fpscr(env, ldtul_p(mem_buf));
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 */
*cpu_fpr_ptr(env, n - 32) = ldq_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 */
ppc_store_fpscr(env, ldq_p(mem_buf));
break;
}
}
return r;
}
#ifndef CONFIG_USER_ONLY
void ppc_gdb_gen_spr_xml(PowerPCCPU *cpu)
{
PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(cpu);
CPUPPCState *env = &cpu->env;
GString *xml;
char *spr_name;
unsigned int num_regs = 0;
int i;
if (pcc->gdb_spr_xml) {
return;
}
xml = g_string_new("<?xml version=\"1.0\"?>");
g_string_append(xml, "<!DOCTYPE target SYSTEM \"gdb-target.dtd\">");
g_string_append(xml, "<feature name=\"org.qemu.power.spr\">");
for (i = 0; i < ARRAY_SIZE(env->spr_cb); i++) {
ppc_spr_t *spr = &env->spr_cb[i];
if (!spr->name) {
continue;
}
spr_name = g_ascii_strdown(spr->name, -1);
g_string_append_printf(xml, "<reg name=\"%s\"", spr_name);
g_free(spr_name);
g_string_append_printf(xml, " bitsize=\"%d\"", TARGET_LONG_BITS);
g_string_append(xml, " group=\"spr\"/>");
/*
* GDB identifies registers based on the order they are
* presented in the XML. These ids will not match QEMU's
* representation (which follows the PowerISA).
*
* Store the position of the current register description so
* we can make the correspondence later.
*/
spr->gdb_id = num_regs;
num_regs++;
}
g_string_append(xml, "</feature>");
pcc->gdb_num_sprs = num_regs;
pcc->gdb_spr_xml = g_string_free(xml, false);
}
const char *ppc_gdb_get_dynamic_xml(CPUState *cs, const char *xml_name)
{
PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(cs);
if (strcmp(xml_name, "power-spr.xml") == 0) {
return pcc->gdb_spr_xml;
}
return NULL;
}
#endif
static bool avr_need_swap(CPUPPCState *env)
{
#ifdef HOST_WORDS_BIGENDIAN
return msr_le;
#else
return !msr_le;
#endif
}
#if !defined(CONFIG_USER_ONLY)
static int gdb_find_spr_idx(CPUPPCState *env, int n)
{
int i;
for (i = 0; i < ARRAY_SIZE(env->spr_cb); i++) {
ppc_spr_t *spr = &env->spr_cb[i];
if (spr->name && spr->gdb_id == n) {
return i;
}
}
return -1;
}
static int gdb_get_spr_reg(CPUPPCState *env, GByteArray *buf, int n)
{
int reg;
int len;
reg = gdb_find_spr_idx(env, n);
if (reg < 0) {
return 0;
}
len = TARGET_LONG_SIZE;
gdb_get_regl(buf, env->spr[reg]);
ppc_maybe_bswap_register(env, gdb_get_reg_ptr(buf, len), len);
return len;
}
static int gdb_set_spr_reg(CPUPPCState *env, uint8_t *mem_buf, int n)
{
int reg;
int len;
reg = gdb_find_spr_idx(env, n);
if (reg < 0) {
return 0;
}
len = TARGET_LONG_SIZE;
ppc_maybe_bswap_register(env, mem_buf, len);
env->spr[reg] = ldn_p(mem_buf, len);
return len;
}
#endif
static int gdb_get_float_reg(CPUPPCState *env, GByteArray *buf, int n)
{
uint8_t *mem_buf;
if (n < 32) {
gdb_get_reg64(buf, *cpu_fpr_ptr(env, n));
mem_buf = gdb_get_reg_ptr(buf, 8);
ppc_maybe_bswap_register(env, mem_buf, 8);
return 8;
}
if (n == 32) {
gdb_get_reg32(buf, env->fpscr);
mem_buf = gdb_get_reg_ptr(buf, 4);
ppc_maybe_bswap_register(env, mem_buf, 4);
return 4;
}
return 0;
}
static int gdb_set_float_reg(CPUPPCState *env, uint8_t *mem_buf, int n)
{
if (n < 32) {
ppc_maybe_bswap_register(env, mem_buf, 8);
*cpu_fpr_ptr(env, n) = ldq_p(mem_buf);
return 8;
}
if (n == 32) {
ppc_maybe_bswap_register(env, mem_buf, 4);
ppc_store_fpscr(env, ldl_p(mem_buf));
return 4;
}
return 0;
}
static int gdb_get_avr_reg(CPUPPCState *env, GByteArray *buf, int n)
{
uint8_t *mem_buf;
if (n < 32) {
ppc_avr_t *avr = cpu_avr_ptr(env, n);
if (!avr_need_swap(env)) {
gdb_get_reg128(buf, avr->u64[0] , avr->u64[1]);
} else {
gdb_get_reg128(buf, avr->u64[1] , avr->u64[0]);
}
mem_buf = gdb_get_reg_ptr(buf, 16);
ppc_maybe_bswap_register(env, mem_buf, 8);
ppc_maybe_bswap_register(env, mem_buf + 8, 8);
return 16;
}
if (n == 32) {
gdb_get_reg32(buf, ppc_get_vscr(env));
mem_buf = gdb_get_reg_ptr(buf, 4);
ppc_maybe_bswap_register(env, mem_buf, 4);
return 4;
}
if (n == 33) {
gdb_get_reg32(buf, (uint32_t)env->spr[SPR_VRSAVE]);
mem_buf = gdb_get_reg_ptr(buf, 4);
ppc_maybe_bswap_register(env, mem_buf, 4);
return 4;
}
return 0;
}
static int gdb_set_avr_reg(CPUPPCState *env, uint8_t *mem_buf, int n)
{
if (n < 32) {
ppc_avr_t *avr = cpu_avr_ptr(env, n);
ppc_maybe_bswap_register(env, mem_buf, 8);
ppc_maybe_bswap_register(env, mem_buf + 8, 8);
if (!avr_need_swap(env)) {
avr->u64[0] = ldq_p(mem_buf);
avr->u64[1] = ldq_p(mem_buf + 8);
} else {
avr->u64[1] = ldq_p(mem_buf);
avr->u64[0] = ldq_p(mem_buf + 8);
}
return 16;
}
if (n == 32) {
ppc_maybe_bswap_register(env, mem_buf, 4);
ppc_store_vscr(env, ldl_p(mem_buf));
return 4;
}
if (n == 33) {
ppc_maybe_bswap_register(env, mem_buf, 4);
env->spr[SPR_VRSAVE] = (target_ulong)ldl_p(mem_buf);
return 4;
}
return 0;
}
static int gdb_get_spe_reg(CPUPPCState *env, GByteArray *buf, int n)
{
if (n < 32) {
#if defined(TARGET_PPC64)
gdb_get_reg32(buf, env->gpr[n] >> 32);
ppc_maybe_bswap_register(env, gdb_get_reg_ptr(buf, 4), 4);
#else
gdb_get_reg32(buf, env->gprh[n]);
#endif
return 4;
}
if (n == 32) {
gdb_get_reg64(buf, env->spe_acc);
ppc_maybe_bswap_register(env, gdb_get_reg_ptr(buf, 8), 8);
return 8;
}
if (n == 33) {
gdb_get_reg32(buf, env->spe_fscr);
ppc_maybe_bswap_register(env, gdb_get_reg_ptr(buf, 4), 4);
return 4;
}
return 0;
}
static int gdb_set_spe_reg(CPUPPCState *env, uint8_t *mem_buf, int n)
{
if (n < 32) {
#if defined(TARGET_PPC64)
target_ulong lo = (uint32_t)env->gpr[n];
target_ulong hi;
ppc_maybe_bswap_register(env, mem_buf, 4);
hi = (target_ulong)ldl_p(mem_buf) << 32;
env->gpr[n] = lo | hi;
#else
env->gprh[n] = ldl_p(mem_buf);
#endif
return 4;
}
if (n == 32) {
ppc_maybe_bswap_register(env, mem_buf, 8);
env->spe_acc = ldq_p(mem_buf);
return 8;
}
if (n == 33) {
ppc_maybe_bswap_register(env, mem_buf, 4);
env->spe_fscr = ldl_p(mem_buf);
return 4;
}
return 0;
}
static int gdb_get_vsx_reg(CPUPPCState *env, GByteArray *buf, int n)
{
if (n < 32) {
gdb_get_reg64(buf, *cpu_vsrl_ptr(env, n));
ppc_maybe_bswap_register(env, gdb_get_reg_ptr(buf, 8), 8);
return 8;
}
return 0;
}
static int gdb_set_vsx_reg(CPUPPCState *env, uint8_t *mem_buf, int n)
{
if (n < 32) {
ppc_maybe_bswap_register(env, mem_buf, 8);
*cpu_vsrl_ptr(env, n) = ldq_p(mem_buf);
return 8;
}
return 0;
}
gchar *ppc_gdb_arch_name(CPUState *cs)
{
#if defined(TARGET_PPC64)
return g_strdup("powerpc:common64");
#else
return g_strdup("powerpc:common");
#endif
}
void ppc_gdb_init(CPUState *cs, PowerPCCPUClass *pcc)
{
if (pcc->insns_flags & PPC_FLOAT) {
gdb_register_coprocessor(cs, gdb_get_float_reg, gdb_set_float_reg,
33, "power-fpu.xml", 0);
}
if (pcc->insns_flags & PPC_ALTIVEC) {
gdb_register_coprocessor(cs, gdb_get_avr_reg, gdb_set_avr_reg,
34, "power-altivec.xml", 0);
}
if (pcc->insns_flags & PPC_SPE) {
gdb_register_coprocessor(cs, gdb_get_spe_reg, gdb_set_spe_reg,
34, "power-spe.xml", 0);
}
if (pcc->insns_flags2 & PPC2_VSX) {
gdb_register_coprocessor(cs, gdb_get_vsx_reg, gdb_set_vsx_reg,
32, "power-vsx.xml", 0);
}
#ifndef CONFIG_USER_ONLY
gdb_register_coprocessor(cs, gdb_get_spr_reg, gdb_set_spr_reg,
pcc->gdb_num_sprs, "power-spr.xml", 0);
#endif
}