[Qemu-devel] [PATCH FYI 02/13] hw/acpi: add i386 callbacks for injecting GPE 04 when the VMGENID changes

[Laszlo Ersek <lersek@redhat.com>]

Add a new method called "vm_generation_id_changed" to the
AcpiDeviceIfClass interface. The new method sends an ACPI notfication when
the VM generation ID is changed. This contributes to the implementation of
requirement R5, from "docs/vmgenid.txt".

This patch is a slight modification of Gal Hammer's

  [PATCH V15 2/5] acpi: add a vm_generation_id_changed method
  http://thread.gmane.org/gmane.comp.emulators.qemu/332451/focus=332453

(for which reason his S-o-b is preserved in the first position). The
changes are (and should be captured in the commit message):

- There's no need for the helper function acpi_vm_generation_id_changed():
  acpi_send_gpe_event() already does the right thing and is at the right
  abstraction level.

- The next available GPE status bit is bit 4 (value 16); less significant
  bits (bits 1 through 3) are already used for PCI, CPU, and memory
  hotplug.

  Furthermore, bit 0 (value 1) is not available (the _L00 method already
  exist in the DSDTs, with empty body as a precaution); probably because
  the ACPI spec (section "Queuing the Matching Control Method for
  Execution") reserves response code 0 for "no outstanding events". In
  other words, _E00 / _L00 can never be queued.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Gal Hammer <ghammer@redhat.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Signed-off-by: Gal Hammer <ghammer@redhat.com>
[lersek@redhat.com: see changes above, plus extended commit message]
Signed-off-by: Laszlo Ersek <lersek@redhat.com>

Signed-off-by: Laszlo Ersek <lersek@redhat.com>
---

Notes:
    fyi:
    - This patch is not actually related to the ACPI work, but this was the
      first one I wrote, when I was still trying to figure out the right
      order to go about this series. So I'm including it here.

 include/hw/acpi/acpi.h               | 1 +
 include/hw/acpi/acpi_dev_interface.h | 4 ++++
 include/hw/acpi/ich9.h               | 1 +
 hw/acpi/ich9.c                       | 8 ++++++++
 hw/acpi/piix4.c                      | 8 ++++++++
 hw/isa/lpc_ich9.c                    | 1 +
 6 files changed, 23 insertions(+)

diff --git a/include/hw/acpi/acpi.h b/include/hw/acpi/acpi.h
index b20bd55..d46095d 100644
--- a/include/hw/acpi/acpi.h
+++ b/include/hw/acpi/acpi.h
@@ -96,6 +96,7 @@ typedef enum {
     ACPI_PCI_HOTPLUG_STATUS = 2,
     ACPI_CPU_HOTPLUG_STATUS = 4,
     ACPI_MEMORY_HOTPLUG_STATUS = 8,
+    ACPI_VMGENID_CHANGED_STATUS = 16,
 } AcpiGPEStatusBits;
 
 /* structs */
diff --git a/include/hw/acpi/acpi_dev_interface.h b/include/hw/acpi/acpi_dev_interface.h
index f245f8d..d0f210f 100644
--- a/include/hw/acpi/acpi_dev_interface.h
+++ b/include/hw/acpi/acpi_dev_interface.h
@@ -28,6 +28,9 @@ typedef struct AcpiDeviceIf {
  * ospm_status: returns status of ACPI device objects, reported
  *              via _OST method if device supports it.
  *
+ * vm_generation_id_changed: notify the guest that its generation ID has been
+ *                           changed.
+ *
  * Interface is designed for providing unified interface
  * to generic ACPI functionality that could be used without
  * knowledge about internals of actual device that implements
@@ -39,5 +42,6 @@ typedef struct AcpiDeviceIfClass {
 
     /* <public> */
     void (*ospm_status)(AcpiDeviceIf *adev, ACPIOSTInfoList ***list);
+    void (*vm_generation_id_changed)(AcpiDeviceIf *adev);
 } AcpiDeviceIfClass;
 #endif
diff --git a/include/hw/acpi/ich9.h b/include/hw/acpi/ich9.h
index 345fd8d..e656f59 100644
--- a/include/hw/acpi/ich9.h
+++ b/include/hw/acpi/ich9.h
@@ -77,4 +77,5 @@ void ich9_pm_device_unplug_cb(ICH9LPCPMRegs *pm, DeviceState *dev,
                               Error **errp);
 
 void ich9_pm_ospm_status(AcpiDeviceIf *adev, ACPIOSTInfoList ***list);
+void ich9_vm_generation_id_changed(AcpiDeviceIf *adev);
 #endif /* HW_ACPI_ICH9_H */
diff --git a/hw/acpi/ich9.c b/hw/acpi/ich9.c
index 1c7fcfa..bd7214e 100644
--- a/hw/acpi/ich9.c
+++ b/hw/acpi/ich9.c
@@ -482,3 +482,11 @@ void ich9_pm_ospm_status(AcpiDeviceIf *adev, ACPIOSTInfoList ***list)
 
     acpi_memory_ospm_status(&s->pm.acpi_memory_hotplug, list);
 }
+
+void ich9_vm_generation_id_changed(AcpiDeviceIf *adev)
+{
+    ICH9LPCState *s = ICH9_LPC_DEVICE(adev);
+    ICH9LPCPMRegs *pm = &s->pm;
+
+    acpi_send_gpe_event(&pm->acpi_regs, pm->irq, ACPI_VMGENID_CHANGED_STATUS);
+}
diff --git a/hw/acpi/piix4.c b/hw/acpi/piix4.c
index 2cd2fee..d83957c 100644
--- a/hw/acpi/piix4.c
+++ b/hw/acpi/piix4.c
@@ -583,6 +583,13 @@ static void piix4_ospm_status(AcpiDeviceIf *adev, ACPIOSTInfoList ***list)
     acpi_memory_ospm_status(&s->acpi_memory_hotplug, list);
 }
 
+static void piix4_vm_generation_id_changed(AcpiDeviceIf *adev)
+{
+    PIIX4PMState *s = PIIX4_PM(adev);
+
+    acpi_send_gpe_event(&s->ar, s->irq, ACPI_VMGENID_CHANGED_STATUS);
+}
+
 static Property piix4_pm_properties[] = {
     DEFINE_PROP_UINT32("smb_io_base", PIIX4PMState, smb_io_base, 0),
     DEFINE_PROP_UINT8(ACPI_PM_PROP_S3_DISABLED, PIIX4PMState, disable_s3, 0),
@@ -621,6 +628,7 @@ static void piix4_pm_class_init(ObjectClass *klass, void *data)
     hc->unplug_request = piix4_device_unplug_request_cb;
     hc->unplug = piix4_device_unplug_cb;
     adevc->ospm_status = piix4_ospm_status;
+    adevc->vm_generation_id_changed = piix4_vm_generation_id_changed;
 }
 
 static const TypeInfo piix4_pm_info = {
diff --git a/hw/isa/lpc_ich9.c b/hw/isa/lpc_ich9.c
index 360699f..bc6b737 100644
--- a/hw/isa/lpc_ich9.c
+++ b/hw/isa/lpc_ich9.c
@@ -724,6 +724,7 @@ static void ich9_lpc_class_init(ObjectClass *klass, void *data)
     hc->unplug_request = ich9_device_unplug_request_cb;
     hc->unplug = ich9_device_unplug_cb;
     adevc->ospm_status = ich9_pm_ospm_status;
+    adevc->vm_generation_id_changed = ich9_vm_generation_id_changed;
 }
 
 static const TypeInfo ich9_lpc_info = {
-- 
1.8.3.1