qemu/target/ppc/compat.c
Greg Kurz 5dfaa532e0 ppc: fix ppc_set_compat() with KVM PR
When running in KVM PR mode, kvmppc_set_compat() always fail because the
current PR implementation doesn't handle KVM_REG_PPC_ARCH_COMPAT. Now that
the machine code inconditionally calls ppc_set_compat_all() at reset time
to restore the compat mode default value (commit 66d5c492dd), it is
impossible to start a guest with PR:

qemu-system-ppc64: Unable to set CPU compatibility mode in KVM:
 Invalid argument

A tentative patch [1] was recently sent by Suraj to address the issue, but
it would prevent the compat mode to be turned off on reset. And we really
don't want to explicitely check for KVM PR. During the patch's review,
David suggested that we should only call the KVM ioctl() if the compat
PVR changes. This allows at least to run with KVM PR, provided no compat
mode is requested from the command line (which should be the case when
running PR nested). This is what this patch does.

While here, we also fix the side effect where KVM would fail but we would
change the CPU state in QEMU anyway.

[1] http://patchwork.ozlabs.org/patch/782039/

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-08-22 21:26:46 +10:00

295 lines
7.8 KiB
C

/*
* PowerPC CPU initialization for qemu.
*
* Copyright 2016, David Gibson, Red Hat Inc. <dgibson@redhat.com>
*
* 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 "sysemu/hw_accel.h"
#include "sysemu/kvm.h"
#include "kvm_ppc.h"
#include "sysemu/cpus.h"
#include "qemu/error-report.h"
#include "qapi/error.h"
#include "qapi/visitor.h"
#include "cpu-models.h"
typedef struct {
const char *name;
uint32_t pvr;
uint64_t pcr;
uint64_t pcr_level;
int max_threads;
} CompatInfo;
static const CompatInfo compat_table[] = {
/*
* Ordered from oldest to newest - the code relies on this
*/
{ /* POWER6, ISA2.05 */
.name = "power6",
.pvr = CPU_POWERPC_LOGICAL_2_05,
.pcr = PCR_COMPAT_3_00 | PCR_COMPAT_2_07 | PCR_COMPAT_2_06 |
PCR_COMPAT_2_05 | PCR_TM_DIS | PCR_VSX_DIS,
.pcr_level = PCR_COMPAT_2_05,
.max_threads = 2,
},
{ /* POWER7, ISA2.06 */
.name = "power7",
.pvr = CPU_POWERPC_LOGICAL_2_06,
.pcr = PCR_COMPAT_3_00 | PCR_COMPAT_2_07 | PCR_COMPAT_2_06 | PCR_TM_DIS,
.pcr_level = PCR_COMPAT_2_06,
.max_threads = 4,
},
{
.name = "power7+",
.pvr = CPU_POWERPC_LOGICAL_2_06_PLUS,
.pcr = PCR_COMPAT_3_00 | PCR_COMPAT_2_07 | PCR_COMPAT_2_06 | PCR_TM_DIS,
.pcr_level = PCR_COMPAT_2_06,
.max_threads = 4,
},
{ /* POWER8, ISA2.07 */
.name = "power8",
.pvr = CPU_POWERPC_LOGICAL_2_07,
.pcr = PCR_COMPAT_3_00 | PCR_COMPAT_2_07,
.pcr_level = PCR_COMPAT_2_07,
.max_threads = 8,
},
{ /* POWER9, ISA3.00 */
.name = "power9",
.pvr = CPU_POWERPC_LOGICAL_3_00,
.pcr = PCR_COMPAT_3_00,
.pcr_level = PCR_COMPAT_3_00,
.max_threads = 4,
},
};
static const CompatInfo *compat_by_pvr(uint32_t pvr)
{
int i;
for (i = 0; i < ARRAY_SIZE(compat_table); i++) {
if (compat_table[i].pvr == pvr) {
return &compat_table[i];
}
}
return NULL;
}
bool ppc_check_compat(PowerPCCPU *cpu, uint32_t compat_pvr,
uint32_t min_compat_pvr, uint32_t max_compat_pvr)
{
PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(cpu);
const CompatInfo *compat = compat_by_pvr(compat_pvr);
const CompatInfo *min = compat_by_pvr(min_compat_pvr);
const CompatInfo *max = compat_by_pvr(max_compat_pvr);
#if !defined(CONFIG_USER_ONLY)
g_assert(cpu->vhyp);
#endif
g_assert(!min_compat_pvr || min);
g_assert(!max_compat_pvr || max);
if (!compat) {
/* Not a recognized logical PVR */
return false;
}
if ((min && (compat < min)) || (max && (compat > max))) {
/* Outside specified range */
return false;
}
if (!(pcc->pcr_supported & compat->pcr_level)) {
/* Not supported by this CPU */
return false;
}
return true;
}
void ppc_set_compat(PowerPCCPU *cpu, uint32_t compat_pvr, Error **errp)
{
const CompatInfo *compat = compat_by_pvr(compat_pvr);
CPUPPCState *env = &cpu->env;
PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(cpu);
uint64_t pcr;
if (!compat_pvr) {
pcr = 0;
} else if (!compat) {
error_setg(errp, "Unknown compatibility PVR 0x%08"PRIx32, compat_pvr);
return;
} else if (!ppc_check_compat(cpu, compat_pvr, 0, 0)) {
error_setg(errp, "Compatibility PVR 0x%08"PRIx32" not valid for CPU",
compat_pvr);
return;
} else {
pcr = compat->pcr;
}
cpu_synchronize_state(CPU(cpu));
if (kvm_enabled() && cpu->compat_pvr != compat_pvr) {
int ret = kvmppc_set_compat(cpu, cpu->compat_pvr);
if (ret < 0) {
error_setg_errno(errp, -ret,
"Unable to set CPU compatibility mode in KVM");
return;
}
}
cpu->compat_pvr = compat_pvr;
env->spr[SPR_PCR] = pcr & pcc->pcr_mask;
}
typedef struct {
uint32_t compat_pvr;
Error *err;
} SetCompatState;
static void do_set_compat(CPUState *cs, run_on_cpu_data arg)
{
PowerPCCPU *cpu = POWERPC_CPU(cs);
SetCompatState *s = arg.host_ptr;
ppc_set_compat(cpu, s->compat_pvr, &s->err);
}
void ppc_set_compat_all(uint32_t compat_pvr, Error **errp)
{
CPUState *cs;
CPU_FOREACH(cs) {
SetCompatState s = {
.compat_pvr = compat_pvr,
.err = NULL,
};
run_on_cpu(cs, do_set_compat, RUN_ON_CPU_HOST_PTR(&s));
if (s.err) {
error_propagate(errp, s.err);
return;
}
}
}
int ppc_compat_max_threads(PowerPCCPU *cpu)
{
const CompatInfo *compat = compat_by_pvr(cpu->compat_pvr);
int n_threads = CPU(cpu)->nr_threads;
if (cpu->compat_pvr) {
g_assert(compat);
n_threads = MIN(n_threads, compat->max_threads);
}
return n_threads;
}
static void ppc_compat_prop_get(Object *obj, Visitor *v, const char *name,
void *opaque, Error **errp)
{
uint32_t compat_pvr = *((uint32_t *)opaque);
const char *value;
if (!compat_pvr) {
value = "";
} else {
const CompatInfo *compat = compat_by_pvr(compat_pvr);
g_assert(compat);
value = compat->name;
}
visit_type_str(v, name, (char **)&value, errp);
}
static void ppc_compat_prop_set(Object *obj, Visitor *v, const char *name,
void *opaque, Error **errp)
{
Error *local_err = NULL;
char *value;
uint32_t compat_pvr;
visit_type_str(v, name, &value, &local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
if (strcmp(value, "") == 0) {
compat_pvr = 0;
} else {
int i;
const CompatInfo *compat = NULL;
for (i = 0; i < ARRAY_SIZE(compat_table); i++) {
if (strcmp(value, compat_table[i].name) == 0) {
compat = &compat_table[i];
break;
}
}
if (!compat) {
error_setg(errp, "Invalid compatibility mode \"%s\"", value);
goto out;
}
compat_pvr = compat->pvr;
}
*((uint32_t *)opaque) = compat_pvr;
out:
g_free(value);
}
void ppc_compat_add_property(Object *obj, const char *name,
uint32_t *compat_pvr, const char *basedesc,
Error **errp)
{
Error *local_err = NULL;
gchar *namesv[ARRAY_SIZE(compat_table) + 1];
gchar *names, *desc;
int i;
object_property_add(obj, name, "string",
ppc_compat_prop_get, ppc_compat_prop_set, NULL,
compat_pvr, &local_err);
if (local_err) {
goto out;
}
for (i = 0; i < ARRAY_SIZE(compat_table); i++) {
/*
* Have to discard const here, because g_strjoinv() takes
* (gchar **), not (const gchar **) :(
*/
namesv[i] = (gchar *)compat_table[i].name;
}
namesv[ARRAY_SIZE(compat_table)] = NULL;
names = g_strjoinv(", ", namesv);
desc = g_strdup_printf("%s. Valid values are %s.", basedesc, names);
object_property_set_description(obj, name, desc, &local_err);
g_free(names);
g_free(desc);
out:
error_propagate(errp, local_err);
}