[Qemu-devel] [PATCH] acpi: Add emulated sleep button

[Stefan Fritsch <sf@sfritsch.de>]

From: Stefan Fritsch <stefan_fritsch@genua.de>

Add an ACPI sleep button and QMP/HMP commands to trigger it.  A sleep
button is a so called "fixed hardware feature", which makes it more
suitable for putting the system to sleep than a laptop lid, for example.

The sleep button is disabled by default (Bit 5 in the FACP flags
register set and no button "device" present in SSDT/DSDT). Clearing said
bit enables it as a fixed feature device.

Signed-off-by: Stefan Fritsch <stefan_fritsch@genua.de>
---
 hmp-commands.hx         | 16 ++++++++++++++++
 hmp.c                   |  5 +++++
 hmp.h                   |  1 +
 hw/acpi/core.c          |  8 ++++++++
 hw/acpi/ich9.c          | 10 ++++++++++
 hw/acpi/piix4.c         | 12 ++++++++++++
 hw/i386/acpi-build.c    |  1 -
 include/hw/acpi/acpi.h  |  2 ++
 include/hw/acpi/ich9.h  |  1 +
 include/sysemu/sysemu.h |  2 ++
 qapi-schema.json        | 12 ++++++++++++
 qmp.c                   |  5 +++++
 tests/test-hmp.c        |  1 +
 vl.c                    | 29 +++++++++++++++++++++++++++++
 14 files changed, 104 insertions(+), 1 deletion(-)

diff --git a/hmp-commands.hx b/hmp-commands.hx
index 1941e19932..8ba4380883 100644
--- a/hmp-commands.hx
+++ b/hmp-commands.hx
@@ -638,6 +638,22 @@ Reset the system.
 ETEXI
 
     {
+        .name       = "system_sleep",
+        .args_type  = "",
+        .params     = "",
+        .help       = "send ACPI sleep event",
+        .cmd = hmp_system_sleep,
+    },
+
+STEXI
+@item system_sleep
+@findex system_sleep
+
+Push the virtual sleep button; if supported the system will enter
+an ACPI sleep state.
+ETEXI
+
+    {
         .name       = "system_powerdown",
         .args_type  = "",
         .params     = "",
diff --git a/hmp.c b/hmp.c
index bf1de747d5..b4b584016c 100644
--- a/hmp.c
+++ b/hmp.c
@@ -1047,6 +1047,11 @@ void hmp_system_reset(Monitor *mon, const QDict *qdict)
     qmp_system_reset(NULL);
 }
 
+void hmp_system_sleep(Monitor *mon, const QDict *qdict)
+{
+    qmp_system_sleep(NULL);
+}
+
 void hmp_system_powerdown(Monitor *mon, const QDict *qdict)
 {
     qmp_system_powerdown(NULL);
diff --git a/hmp.h b/hmp.h
index 1ff455295e..15b53de9ed 100644
--- a/hmp.h
+++ b/hmp.h
@@ -45,6 +45,7 @@ void hmp_info_iothreads(Monitor *mon, const QDict *qdict);
 void hmp_quit(Monitor *mon, const QDict *qdict);
 void hmp_stop(Monitor *mon, const QDict *qdict);
 void hmp_system_reset(Monitor *mon, const QDict *qdict);
+void hmp_system_sleep(Monitor *mon, const QDict *qdict);
 void hmp_system_powerdown(Monitor *mon, const QDict *qdict);
 void hmp_cpu(Monitor *mon, const QDict *qdict);
 void hmp_memsave(Monitor *mon, const QDict *qdict);
diff --git a/hw/acpi/core.c b/hw/acpi/core.c
index 95fcac95a2..2ee64b6878 100644
--- a/hw/acpi/core.c
+++ b/hw/acpi/core.c
@@ -422,6 +422,14 @@ void acpi_pm1_evt_power_down(ACPIREGS *ar)
     }
 }
 
+void acpi_pm1_evt_sleep(ACPIREGS *ar)
+{
+    if (ar->pm1.evt.en & ACPI_BITMASK_SLEEP_BUTTON_ENABLE) {
+        ar->pm1.evt.sts |= ACPI_BITMASK_SLEEP_BUTTON_STATUS;
+        ar->tmr.update_sci(ar);
+    }
+}
+
 void acpi_pm1_evt_reset(ACPIREGS *ar)
 {
     ar->pm1.evt.sts = 0;
diff --git a/hw/acpi/ich9.c b/hw/acpi/ich9.c
index c5d8646abc..3faeab4d2e 100644
--- a/hw/acpi/ich9.c
+++ b/hw/acpi/ich9.c
@@ -260,6 +260,14 @@ static void pm_reset(void *opaque)
     acpi_update_sci(&pm->acpi_regs, pm->irq);
 }
 
+static void pm_sleep_req(Notifier *n, void *opaque)
+{
+    ICH9LPCPMRegs *pm = container_of(n, ICH9LPCPMRegs, sleep_notifier);
+
+    acpi_pm1_evt_sleep(&pm->acpi_regs);
+}
+
+
 static void pm_powerdown_req(Notifier *n, void *opaque)
 {
     ICH9LPCPMRegs *pm = container_of(n, ICH9LPCPMRegs, powerdown_notifier);
@@ -299,6 +307,8 @@ void ich9_pm_init(PCIDevice *lpc_pci, ICH9LPCPMRegs *pm,
     qemu_register_reset(pm_reset, pm);
     pm->powerdown_notifier.notify = pm_powerdown_req;
     qemu_register_powerdown_notifier(&pm->powerdown_notifier);
+    pm->sleep_notifier.notify = pm_sleep_req;
+    qemu_register_sleep_notifier(&pm->sleep_notifier);
 
     legacy_acpi_cpu_hotplug_init(pci_address_space_io(lpc_pci),
         OBJECT(lpc_pci), &pm->gpe_cpu, ICH9_CPU_HOTPLUG_IO_BASE);
diff --git a/hw/acpi/piix4.c b/hw/acpi/piix4.c
index f276967365..15e20976c3 100644
--- a/hw/acpi/piix4.c
+++ b/hw/acpi/piix4.c
@@ -79,6 +79,7 @@ typedef struct PIIX4PMState {
     int smm_enabled;
     Notifier machine_ready;
     Notifier powerdown_notifier;
+    Notifier sleep_notifier;
 
     AcpiPciHpState acpi_pci_hotplug;
     bool use_acpi_pci_hotplug;
@@ -371,6 +372,15 @@ static void piix4_pm_powerdown_req(Notifier *n, void *opaque)
     acpi_pm1_evt_power_down(&s->ar);
 }
 
+static void piix4_pm_sleep_req(Notifier *n, void *opaque)
+{
+    PIIX4PMState *s = container_of(n, PIIX4PMState, sleep_notifier);
+
+    assert(s != NULL);
+    acpi_pm1_evt_sleep(&s->ar);
+}
+
+
 static void piix4_device_plug_cb(HotplugHandler *hotplug_dev,
                                  DeviceState *dev, Error **errp)
 {
@@ -535,6 +545,8 @@ static void piix4_pm_realize(PCIDevice *dev, Error **errp)
 
     s->powerdown_notifier.notify = piix4_pm_powerdown_req;
     qemu_register_powerdown_notifier(&s->powerdown_notifier);
+    s->sleep_notifier.notify = piix4_pm_sleep_req;
+    qemu_register_sleep_notifier(&s->sleep_notifier);
 
     s->machine_ready.notify = piix4_pm_machine_ready;
     qemu_add_machine_init_done_notifier(&s->machine_ready);
diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index 6b7bade183..06b28dacfe 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -294,7 +294,6 @@ static void fadt_setup(AcpiFadtDescriptorRev3 *fadt, AcpiPmInfo *pm)
     fadt->plvl3_lat = cpu_to_le16(0xfff); /* C3 state not supported */
     fadt->flags = cpu_to_le32((1 << ACPI_FADT_F_WBINVD) |
                               (1 << ACPI_FADT_F_PROC_C1) |
-                              (1 << ACPI_FADT_F_SLP_BUTTON) |
                               (1 << ACPI_FADT_F_RTC_S4));
     fadt->flags |= cpu_to_le32(1 << ACPI_FADT_F_USE_PLATFORM_CLOCK);
     /* APIC destination mode ("Flat Logical") has an upper limit of 8 CPUs
diff --git a/include/hw/acpi/acpi.h b/include/hw/acpi/acpi.h
index 7b3d93cf0d..51cf901ef6 100644
--- a/include/hw/acpi/acpi.h
+++ b/include/hw/acpi/acpi.h
@@ -78,6 +78,7 @@
 #define ACPI_BITMASK_PM1_COMMON_ENABLED         ( \
         ACPI_BITMASK_RT_CLOCK_ENABLE        | \
         ACPI_BITMASK_POWER_BUTTON_ENABLE    | \
+        ACPI_BITMASK_SLEEP_BUTTON_ENABLE    | \
         ACPI_BITMASK_GLOBAL_LOCK_ENABLE     | \
         ACPI_BITMASK_TIMER_ENABLE)
 
@@ -148,6 +149,7 @@ void acpi_pm_tmr_reset(ACPIREGS *ar);
 /* PM1a_EVT: piix and ich9 don't implement PM1b. */
 uint16_t acpi_pm1_evt_get_sts(ACPIREGS *ar);
 void acpi_pm1_evt_power_down(ACPIREGS *ar);
+void acpi_pm1_evt_sleep(ACPIREGS *ar);
 void acpi_pm1_evt_reset(ACPIREGS *ar);
 void acpi_pm1_evt_init(ACPIREGS *ar, acpi_update_sci_fn update_sci,
                        MemoryRegion *parent);
diff --git a/include/hw/acpi/ich9.h b/include/hw/acpi/ich9.h
index a352c94fde..2073eec168 100644
--- a/include/hw/acpi/ich9.h
+++ b/include/hw/acpi/ich9.h
@@ -48,6 +48,7 @@ typedef struct ICH9LPCPMRegs {
 
     uint32_t pm_io_base;
     Notifier powerdown_notifier;
+    Notifier sleep_notifier;
 
     bool cpu_hotplug_legacy;
     AcpiCpuHotplug gpe_cpu;
diff --git a/include/sysemu/sysemu.h b/include/sysemu/sysemu.h
index b21369672a..00f54653dc 100644
--- a/include/sysemu/sysemu.h
+++ b/include/sysemu/sysemu.h
@@ -75,6 +75,8 @@ void qemu_register_wakeup_notifier(Notifier *notifier);
 void qemu_system_shutdown_request(ShutdownCause reason);
 void qemu_system_powerdown_request(void);
 void qemu_register_powerdown_notifier(Notifier *notifier);
+void qemu_system_sleep_request(void);
+void qemu_register_sleep_notifier(Notifier *notifier);
 void qemu_system_debug_request(void);
 void qemu_system_vmstop_request(RunState reason);
 void qemu_system_vmstop_request_prepare(void);
diff --git a/qapi-schema.json b/qapi-schema.json
index 8b015bee2e..c6ccfcd70f 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -2314,6 +2314,18 @@
 { 'command': 'system_reset' }
 
 ##
+# @system_sleep:
+#
+# Requests that a guest perform a ACPI sleep transition by pushing a virtual
+# sleep button.
+#
+# Notes: A guest may or may not respond to this command.  This command
+#        returning does not indicate that a guest has accepted the request or
+#        that it has gone to sleep.
+##
+{ 'command': 'system_sleep' }
+
+##
 # @system_powerdown:
 #
 # Requests that a guest perform a powerdown operation.
diff --git a/qmp.c b/qmp.c
index b86201e349..bc1f2e3d7f 100644
--- a/qmp.c
+++ b/qmp.c
@@ -108,6 +108,11 @@ void qmp_system_reset(Error **errp)
     qemu_system_reset_request(SHUTDOWN_CAUSE_HOST_QMP);
 }
 
+void qmp_system_sleep(Error **erp)
+{
+    qemu_system_sleep_request();
+}
+
 void qmp_system_powerdown(Error **erp)
 {
     qemu_system_powerdown_request();
diff --git a/tests/test-hmp.c b/tests/test-hmp.c
index d77b3c8710..3fa850bf1e 100644
--- a/tests/test-hmp.c
+++ b/tests/test-hmp.c
@@ -67,6 +67,7 @@ static const char *hmp_cmds[] = {
     "sum 0 512",
     "x /8i 0x100",
     "xp /16x 0",
+    "system_sleep",
     NULL
 };
 
diff --git a/vl.c b/vl.c
index fb6b2efafa..6a0f847dcf 100644
--- a/vl.c
+++ b/vl.c
@@ -1608,6 +1608,7 @@ static ShutdownCause reset_requested;
 static ShutdownCause shutdown_requested;
 static int shutdown_signal;
 static pid_t shutdown_pid;
+static int sleep_requested;
 static int powerdown_requested;
 static int debug_requested;
 static int suspend_requested;
@@ -1618,6 +1619,8 @@ static NotifierList suspend_notifiers =
     NOTIFIER_LIST_INITIALIZER(suspend_notifiers);
 static NotifierList wakeup_notifiers =
     NOTIFIER_LIST_INITIALIZER(wakeup_notifiers);
+static NotifierList sleep_notifiers =
+    NOTIFIER_LIST_INITIALIZER(sleep_notifiers);
 static uint32_t wakeup_reason_mask = ~(1 << QEMU_WAKEUP_REASON_NONE);
 
 ShutdownCause qemu_shutdown_requested_get(void)
@@ -1838,6 +1841,24 @@ static void qemu_system_powerdown(void)
     notifier_list_notify(&powerdown_notifiers, NULL);
 }
 
+static void qemu_system_sleep(void)
+{
+    notifier_list_notify(&sleep_notifiers, NULL);
+}
+
+static int qemu_sleep_requested(void)
+{
+    int r = sleep_requested;
+    sleep_requested = 0;
+    return r;
+}
+
+void qemu_system_sleep_request(void)
+{
+    sleep_requested = 1;
+    qemu_notify_event();
+}
+
 void qemu_system_powerdown_request(void)
 {
     trace_qemu_system_powerdown_request();
@@ -1850,6 +1871,11 @@ void qemu_register_powerdown_notifier(Notifier *notifier)
     notifier_list_add(&powerdown_notifiers, notifier);
 }
 
+void qemu_register_sleep_notifier(Notifier *notifier)
+{
+    notifier_list_add(&sleep_notifiers, notifier);
+}
+
 void qemu_system_debug_request(void)
 {
     debug_requested = 1;
@@ -1899,6 +1925,9 @@ static bool main_loop_should_exit(void)
     if (qemu_powerdown_requested()) {
         qemu_system_powerdown();
     }
+    if (qemu_sleep_requested()) {
+        qemu_system_sleep();
+    }
     if (qemu_vmstop_requested(&r)) {
         vm_stop(r);
     }
-- 
2.11.0