qemu/target/s390x/cpu.c
David Hildenbrand 741a4ec186 target/s390x: special handling when starting a CPU with WAIT PSW
When we try to start a CPU with a WAIT PSW, we have to take care that
TCG will actually try to continue executing instructions.

We must therefore really only unhalt the CPU if we don't have a WAIT
PSW. Also document the special order for restart interrupts, which
load a new PSW and change the state to operating.

To keep KVM working, simply don't have a look at the WAIT bit when
loading the PSW. Otherwise the behavior of a restart interrupt when
a CPU stopped would be changed.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170928203708.9376-31-david@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2017-10-20 13:32:10 +02:00

531 lines
14 KiB
C

/*
* QEMU S/390 CPU
*
* Copyright (c) 2009 Ulrich Hecht
* Copyright (c) 2011 Alexander Graf
* Copyright (c) 2012 SUSE LINUX Products GmbH
* Copyright (c) 2012 IBM Corp.
*
* 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/lgpl-2.1.html>
* Contributions after 2012-12-11 are licensed under the terms of the
* GNU GPL, version 2 or (at your option) any later version.
*/
#include "qemu/osdep.h"
#include "qapi/error.h"
#include "cpu.h"
#include "internal.h"
#include "kvm_s390x.h"
#include "sysemu/kvm.h"
#include "qemu-common.h"
#include "qemu/cutils.h"
#include "qemu/timer.h"
#include "qemu/error-report.h"
#include "trace.h"
#include "qapi/visitor.h"
#include "exec/exec-all.h"
#include "hw/qdev-properties.h"
#ifndef CONFIG_USER_ONLY
#include "hw/hw.h"
#include "sysemu/arch_init.h"
#include "sysemu/sysemu.h"
#endif
#define CR0_RESET 0xE0UL
#define CR14_RESET 0xC2000000UL;
static void s390_cpu_set_pc(CPUState *cs, vaddr value)
{
S390CPU *cpu = S390_CPU(cs);
cpu->env.psw.addr = value;
}
static bool s390_cpu_has_work(CPUState *cs)
{
S390CPU *cpu = S390_CPU(cs);
/* STOPPED cpus can never wake up */
if (s390_cpu_get_state(cpu) != CPU_STATE_LOAD &&
s390_cpu_get_state(cpu) != CPU_STATE_OPERATING) {
return false;
}
if (!(cs->interrupt_request & CPU_INTERRUPT_HARD)) {
return false;
}
return s390_cpu_has_int(cpu);
}
#if !defined(CONFIG_USER_ONLY)
/* S390CPUClass::load_normal() */
static void s390_cpu_load_normal(CPUState *s)
{
S390CPU *cpu = S390_CPU(s);
cpu->env.psw.addr = ldl_phys(s->as, 4) & PSW_MASK_ESA_ADDR;
cpu->env.psw.mask = PSW_MASK_32 | PSW_MASK_64;
s390_cpu_set_state(CPU_STATE_OPERATING, cpu);
}
#endif
/* S390CPUClass::cpu_reset() */
static void s390_cpu_reset(CPUState *s)
{
S390CPU *cpu = S390_CPU(s);
S390CPUClass *scc = S390_CPU_GET_CLASS(cpu);
CPUS390XState *env = &cpu->env;
env->pfault_token = -1UL;
scc->parent_reset(s);
cpu->env.sigp_order = 0;
s390_cpu_set_state(CPU_STATE_STOPPED, cpu);
}
/* S390CPUClass::initial_reset() */
static void s390_cpu_initial_reset(CPUState *s)
{
S390CPU *cpu = S390_CPU(s);
CPUS390XState *env = &cpu->env;
int i;
s390_cpu_reset(s);
/* initial reset does not clear everything! */
memset(&env->start_initial_reset_fields, 0,
offsetof(CPUS390XState, end_reset_fields) -
offsetof(CPUS390XState, start_initial_reset_fields));
/* architectured initial values for CR 0 and 14 */
env->cregs[0] = CR0_RESET;
env->cregs[14] = CR14_RESET;
/* architectured initial value for Breaking-Event-Address register */
env->gbea = 1;
env->pfault_token = -1UL;
for (i = 0; i < ARRAY_SIZE(env->io_index); i++) {
env->io_index[i] = -1;
}
env->mchk_index = -1;
/* tininess for underflow is detected before rounding */
set_float_detect_tininess(float_tininess_before_rounding,
&env->fpu_status);
/* Reset state inside the kernel that we cannot access yet from QEMU. */
if (kvm_enabled()) {
kvm_s390_reset_vcpu(cpu);
}
}
/* CPUClass:reset() */
static void s390_cpu_full_reset(CPUState *s)
{
S390CPU *cpu = S390_CPU(s);
S390CPUClass *scc = S390_CPU_GET_CLASS(cpu);
CPUS390XState *env = &cpu->env;
int i;
scc->parent_reset(s);
cpu->env.sigp_order = 0;
s390_cpu_set_state(CPU_STATE_STOPPED, cpu);
memset(env, 0, offsetof(CPUS390XState, end_reset_fields));
/* architectured initial values for CR 0 and 14 */
env->cregs[0] = CR0_RESET;
env->cregs[14] = CR14_RESET;
/* architectured initial value for Breaking-Event-Address register */
env->gbea = 1;
env->pfault_token = -1UL;
for (i = 0; i < ARRAY_SIZE(env->io_index); i++) {
env->io_index[i] = -1;
}
env->mchk_index = -1;
/* tininess for underflow is detected before rounding */
set_float_detect_tininess(float_tininess_before_rounding,
&env->fpu_status);
/* Reset state inside the kernel that we cannot access yet from QEMU. */
if (kvm_enabled()) {
kvm_s390_reset_vcpu(cpu);
}
}
#if !defined(CONFIG_USER_ONLY)
static void s390_cpu_machine_reset_cb(void *opaque)
{
S390CPU *cpu = opaque;
run_on_cpu(CPU(cpu), s390_do_cpu_full_reset, RUN_ON_CPU_NULL);
}
#endif
static void s390_cpu_disas_set_info(CPUState *cpu, disassemble_info *info)
{
info->mach = bfd_mach_s390_64;
info->print_insn = print_insn_s390;
}
static void s390_cpu_realizefn(DeviceState *dev, Error **errp)
{
CPUState *cs = CPU(dev);
S390CPUClass *scc = S390_CPU_GET_CLASS(dev);
#if !defined(CONFIG_USER_ONLY)
S390CPU *cpu = S390_CPU(dev);
#endif
Error *err = NULL;
/* the model has to be realized before qemu_init_vcpu() due to kvm */
s390_realize_cpu_model(cs, &err);
if (err) {
goto out;
}
#if !defined(CONFIG_USER_ONLY)
if (cpu->env.core_id >= max_cpus) {
error_setg(&err, "Unable to add CPU with core-id: %" PRIu32
", maximum core-id: %d", cpu->env.core_id,
max_cpus - 1);
goto out;
}
if (cpu_exists(cpu->env.core_id)) {
error_setg(&err, "Unable to add CPU with core-id: %" PRIu32
", it already exists", cpu->env.core_id);
goto out;
}
/* sync cs->cpu_index and env->core_id. The latter is needed for TCG. */
cs->cpu_index = cpu->env.core_id;
#endif
cpu_exec_realizefn(cs, &err);
if (err != NULL) {
goto out;
}
#if !defined(CONFIG_USER_ONLY)
qemu_register_reset(s390_cpu_machine_reset_cb, cpu);
#endif
s390_cpu_gdb_init(cs);
qemu_init_vcpu(cs);
#if !defined(CONFIG_USER_ONLY)
run_on_cpu(cs, s390_do_cpu_full_reset, RUN_ON_CPU_NULL);
#else
cpu_reset(cs);
#endif
scc->parent_realize(dev, &err);
out:
error_propagate(errp, err);
}
static void s390_cpu_initfn(Object *obj)
{
CPUState *cs = CPU(obj);
S390CPU *cpu = S390_CPU(obj);
CPUS390XState *env = &cpu->env;
static bool inited;
#if !defined(CONFIG_USER_ONLY)
struct tm tm;
#endif
cs->env_ptr = env;
cs->halted = 1;
cs->exception_index = EXCP_HLT;
s390_cpu_model_register_props(obj);
#if !defined(CONFIG_USER_ONLY)
qemu_get_timedate(&tm, 0);
env->tod_offset = TOD_UNIX_EPOCH +
(time2tod(mktimegm(&tm)) * 1000000000ULL);
env->tod_basetime = 0;
env->tod_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, s390x_tod_timer, cpu);
env->cpu_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, s390x_cpu_timer, cpu);
s390_cpu_set_state(CPU_STATE_STOPPED, cpu);
#endif
if (tcg_enabled() && !inited) {
inited = true;
s390x_translate_init();
}
}
static void s390_cpu_finalize(Object *obj)
{
#if !defined(CONFIG_USER_ONLY)
S390CPU *cpu = S390_CPU(obj);
qemu_unregister_reset(s390_cpu_machine_reset_cb, cpu);
g_free(cpu->irqstate);
#endif
}
#if !defined(CONFIG_USER_ONLY)
static bool disabled_wait(CPUState *cpu)
{
return cpu->halted && !(S390_CPU(cpu)->env.psw.mask &
(PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK));
}
static unsigned s390_count_running_cpus(void)
{
CPUState *cpu;
int nr_running = 0;
CPU_FOREACH(cpu) {
uint8_t state = S390_CPU(cpu)->env.cpu_state;
if (state == CPU_STATE_OPERATING ||
state == CPU_STATE_LOAD) {
if (!disabled_wait(cpu)) {
nr_running++;
}
}
}
return nr_running;
}
unsigned int s390_cpu_halt(S390CPU *cpu)
{
CPUState *cs = CPU(cpu);
trace_cpu_halt(cs->cpu_index);
if (!cs->halted) {
cs->halted = 1;
cs->exception_index = EXCP_HLT;
}
return s390_count_running_cpus();
}
void s390_cpu_unhalt(S390CPU *cpu)
{
CPUState *cs = CPU(cpu);
trace_cpu_unhalt(cs->cpu_index);
if (cs->halted) {
cs->halted = 0;
cs->exception_index = -1;
}
}
unsigned int s390_cpu_set_state(uint8_t cpu_state, S390CPU *cpu)
{
trace_cpu_set_state(CPU(cpu)->cpu_index, cpu_state);
switch (cpu_state) {
case CPU_STATE_STOPPED:
case CPU_STATE_CHECK_STOP:
/* halt the cpu for common infrastructure */
s390_cpu_halt(cpu);
break;
case CPU_STATE_OPERATING:
case CPU_STATE_LOAD:
/*
* Starting a CPU with a PSW WAIT bit set:
* KVM: handles this internally and triggers another WAIT exit.
* TCG: will actually try to continue to run. Don't unhalt, will
* be done when the CPU actually has work (an interrupt).
*/
if (!tcg_enabled() || !(cpu->env.psw.mask & PSW_MASK_WAIT)) {
s390_cpu_unhalt(cpu);
}
break;
default:
error_report("Requested CPU state is not a valid S390 CPU state: %u",
cpu_state);
exit(1);
}
if (kvm_enabled() && cpu->env.cpu_state != cpu_state) {
kvm_s390_set_cpu_state(cpu, cpu_state);
}
cpu->env.cpu_state = cpu_state;
return s390_count_running_cpus();
}
int s390_get_clock(uint8_t *tod_high, uint64_t *tod_low)
{
int r = 0;
if (kvm_enabled()) {
r = kvm_s390_get_clock_ext(tod_high, tod_low);
if (r == -ENXIO) {
return kvm_s390_get_clock(tod_high, tod_low);
}
} else {
/* Fixme TCG */
*tod_high = 0;
*tod_low = 0;
}
return r;
}
int s390_set_clock(uint8_t *tod_high, uint64_t *tod_low)
{
int r = 0;
if (kvm_enabled()) {
r = kvm_s390_set_clock_ext(tod_high, tod_low);
if (r == -ENXIO) {
return kvm_s390_set_clock(tod_high, tod_low);
}
}
/* Fixme TCG */
return r;
}
int s390_set_memory_limit(uint64_t new_limit, uint64_t *hw_limit)
{
if (kvm_enabled()) {
return kvm_s390_set_mem_limit(new_limit, hw_limit);
}
return 0;
}
void s390_cmma_reset(void)
{
if (kvm_enabled()) {
kvm_s390_cmma_reset();
}
}
int s390_get_memslot_count(void)
{
if (kvm_enabled()) {
return kvm_s390_get_memslot_count();
} else {
return MAX_AVAIL_SLOTS;
}
}
int s390_assign_subch_ioeventfd(EventNotifier *notifier, uint32_t sch_id,
int vq, bool assign)
{
if (kvm_enabled()) {
return kvm_s390_assign_subch_ioeventfd(notifier, sch_id, vq, assign);
} else {
return 0;
}
}
void s390_crypto_reset(void)
{
if (kvm_enabled()) {
kvm_s390_crypto_reset();
}
}
bool s390_get_squash_mcss(void)
{
if (object_property_get_bool(OBJECT(qdev_get_machine()), "s390-squash-mcss",
NULL)) {
return true;
}
return false;
}
void s390_enable_css_support(S390CPU *cpu)
{
if (kvm_enabled()) {
kvm_s390_enable_css_support(cpu);
}
}
#endif
static gchar *s390_gdb_arch_name(CPUState *cs)
{
return g_strdup("s390:64-bit");
}
static Property s390x_cpu_properties[] = {
#if !defined(CONFIG_USER_ONLY)
DEFINE_PROP_UINT32("core-id", S390CPU, env.core_id, 0),
#endif
DEFINE_PROP_END_OF_LIST()
};
static void s390_cpu_class_init(ObjectClass *oc, void *data)
{
S390CPUClass *scc = S390_CPU_CLASS(oc);
CPUClass *cc = CPU_CLASS(scc);
DeviceClass *dc = DEVICE_CLASS(oc);
scc->parent_realize = dc->realize;
dc->realize = s390_cpu_realizefn;
dc->props = s390x_cpu_properties;
dc->user_creatable = true;
scc->parent_reset = cc->reset;
#if !defined(CONFIG_USER_ONLY)
scc->load_normal = s390_cpu_load_normal;
#endif
scc->cpu_reset = s390_cpu_reset;
scc->initial_cpu_reset = s390_cpu_initial_reset;
cc->reset = s390_cpu_full_reset;
cc->class_by_name = s390_cpu_class_by_name,
cc->has_work = s390_cpu_has_work;
#ifdef CONFIG_TCG
cc->do_interrupt = s390_cpu_do_interrupt;
#endif
cc->dump_state = s390_cpu_dump_state;
cc->set_pc = s390_cpu_set_pc;
cc->gdb_read_register = s390_cpu_gdb_read_register;
cc->gdb_write_register = s390_cpu_gdb_write_register;
#ifdef CONFIG_USER_ONLY
cc->handle_mmu_fault = s390_cpu_handle_mmu_fault;
#else
cc->get_phys_page_debug = s390_cpu_get_phys_page_debug;
cc->vmsd = &vmstate_s390_cpu;
cc->write_elf64_note = s390_cpu_write_elf64_note;
#ifdef CONFIG_TCG
cc->cpu_exec_interrupt = s390_cpu_exec_interrupt;
cc->debug_excp_handler = s390x_cpu_debug_excp_handler;
cc->do_unaligned_access = s390x_cpu_do_unaligned_access;
#endif
#endif
cc->disas_set_info = s390_cpu_disas_set_info;
cc->gdb_num_core_regs = S390_NUM_CORE_REGS;
cc->gdb_core_xml_file = "s390x-core64.xml";
cc->gdb_arch_name = s390_gdb_arch_name;
s390_cpu_model_class_register_props(oc);
}
static const TypeInfo s390_cpu_type_info = {
.name = TYPE_S390_CPU,
.parent = TYPE_CPU,
.instance_size = sizeof(S390CPU),
.instance_init = s390_cpu_initfn,
.instance_finalize = s390_cpu_finalize,
.abstract = true,
.class_size = sizeof(S390CPUClass),
.class_init = s390_cpu_class_init,
};
static void s390_cpu_register_types(void)
{
type_register_static(&s390_cpu_type_info);
}
type_init(s390_cpu_register_types)