[RFC PATCH v3 18/19] Implement _PS3 for dimm

[Vasilis Liaskovitis]

This will allow us to update dimm state on OSPM-initiated eject operations e.g.
with "echo 1 > /sys/bus/acpi/devices/PNP0C80:00/eject"

Signed-off-by: Vasilis Liaskovitis 
---
 docs/specs/acpi_hotplug.txt |    7 +++++++
 hw/acpi_piix4.c             |    5 +++++
 hw/dimm.c                   |    3 +++
 hw/dimm.h                   |    3 ++-
 4 files changed, 17 insertions(+), 1 deletions(-)

diff --git a/docs/specs/acpi_hotplug.txt b/docs/specs/acpi_hotplug.txt
index 536da16..69868fe 100644
--- a/docs/specs/acpi_hotplug.txt
+++ b/docs/specs/acpi_hotplug.txt
@@ -45,3 +45,10 @@ insertion failed.
 Written by ACPI memory device _OST method to notify qemu of failed
 hot-add.  Write-only.

+Memory Dimm _PS3 power-off initiated by OSPM (IO port 0xafa4, 1-byte access):
+---------------------------------------------------------------
+Dimm hot-add _PS3 initiated by OSPM. Byte value indicates Dimm slot which
+entered D3 state.
+
+Written by ACPI memory device _PS3 method to notify qemu of power-off state for
+the dimm.  Write-only.
diff --git a/hw/acpi_piix4.c b/hw/acpi_piix4.c
index 8bf58a6..aad78ca 100644
--- a/hw/acpi_piix4.c
+++ b/hw/acpi_piix4.c
@@ -52,6 +52,7 @@
 #define MEM_OST_REMOVE_FAIL 0xafa1
 #define MEM_OST_ADD_SUCCESS 0xafa2
 #define MEM_OST_ADD_FAIL 0xafa3
+#define MEM_PS3 0xafa4

#define PIIX4_MEM_HOTPLUG_STATUS 8
 #define PIIX4_PCI_HOTPLUG_STATUS 2
@@ -545,6 +546,9 @@ static void gpe_writeb(void *opaque, uint32_t addr, uint32_t val)
         case MEM_OST_ADD_FAIL:
             dimm_notify(val, DIMM_ADD_FAIL);
             break;
+        case MEM_PS3:
+            dimm_notify(val, DIMM_OSPM_POWEROFF);
+            break;
         default:
             acpi_gpe_ioport_writeb(&s->ar, addr, val);
     }
@@ -621,6 +625,7 @@ static void piix4_acpi_system_hot_add_init(PCIBus *bus, PIIX4PMState *s)
     register_ioport_write(MEM_OST_REMOVE_FAIL, 1, 1,  gpe_writeb, s);
     register_ioport_write(MEM_OST_ADD_SUCCESS, 1, 1,  gpe_writeb, s);
     register_ioport_write(MEM_OST_ADD_FAIL, 1, 1,  gpe_writeb, s);
+    register_ioport_write(MEM_PS3, 1, 1,  gpe_writeb, s);

for(i = 0; i < DIMM_BITMAP_BYTES; i++) {
         s->gperegs.mems_sts[i] = 0;
diff --git a/hw/dimm.c b/hw/dimm.c
index b993668..08f66d5 100644
--- a/hw/dimm.c
+++ b/hw/dimm.c
@@ -319,6 +319,9 @@ void dimm_notify(uint32_t idx, uint32_t event)
             qdev_simple_unplug_cb((DeviceState*)s);
             QTAILQ_INSERT_TAIL(&bus->dimm_hp_result_queue, result, next);
             break;
+        case DIMM_OSPM_POWEROFF:
+            if (bus->dimm_revert)
+                bus->dimm_revert(bus->dimm_hotplug_qdev, s, 1);
         default:
             g_free(result);
             break;
diff --git a/hw/dimm.h b/hw/dimm.h
index ce091fe..8d73b8f 100644
--- a/hw/dimm.h
+++ b/hw/dimm.h
@@ -15,7 +15,8 @@ typedef enum {
     DIMM_REMOVE_SUCCESS = 0,
     DIMM_REMOVE_FAIL = 1,
     DIMM_ADD_SUCCESS = 2,
-    DIMM_ADD_FAIL = 3
+    DIMM_ADD_FAIL = 3,
+    DIMM_OSPM_POWEROFF = 4
 } dimm_hp_result_code;

typedef enum {