[Qemu-devel] [PATCH 7/8] pc: acpi: memhp: nvdimm hotplug support

[Xiao Guangrong <guangrong.xiao@linux.intel.com>]

It notifies the nvdimm root device if there is a nvdimm device
plugged/unplugged

A new bit is used to indicates it is a nvdimm device

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
---
 docs/specs/acpi_mem_hotplug.txt |  4 +++-
 hw/acpi/memory_hotplug.c        |  5 -----
 hw/i386/acpi-build.c            | 26 ++++++++++++++++++++++----
 hw/mem/nvdimm.c                 |  4 ----
 include/hw/acpi/pc-hotplug.h    |  1 +
 5 files changed, 26 insertions(+), 14 deletions(-)

diff --git a/docs/specs/acpi_mem_hotplug.txt b/docs/specs/acpi_mem_hotplug.txt
index 3df3620..cd9e233 100644
--- a/docs/specs/acpi_mem_hotplug.txt
+++ b/docs/specs/acpi_mem_hotplug.txt
@@ -21,7 +21,9 @@ Memory hot-plug interface (IO port 0xa00-0xa17, 1-4 byte access):
                  It's valid only when bit 1 is set.
               2: Device remove event, used to distinguish device for which
                  no device eject request to OSPM was issued.
-              3-7: reserved and should be ignored by OSPM
+              3: reserved and should be ignored by OSPM
+              4: Device is a NVDIMM device.
+              5-7: reserved and should be ignored by OSPM
       [0x15-0x17] reserved
 
   write access:
diff --git a/hw/acpi/memory_hotplug.c b/hw/acpi/memory_hotplug.c
index 73fa62d..d1c2e92 100644
--- a/hw/acpi/memory_hotplug.c
+++ b/hw/acpi/memory_hotplug.c
@@ -239,11 +239,6 @@ void acpi_memory_plug_cb(HotplugHandler *hotplug_dev, MemHotplugState *mem_st,
                          DeviceState *dev, Error **errp)
 {
     MemStatus *mdev;
-    DeviceClass *dc = DEVICE_GET_CLASS(dev);
-
-    if (!dc->hotpluggable) {
-        return;
-    }
 
     mdev = acpi_memory_slot_status(mem_st, dev, errp);
     if (!mdev) {
diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index de4a603..eeaf925 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -951,9 +951,10 @@ static Aml *build_crs(PCIHostState *host,
     return crs;
 }
 
-static void build_memory_devices(Aml *sb_scope, int nr_mem,
-                                 uint16_t io_base, uint16_t io_len)
+static void build_memory_devices(Aml *sb_scope, int nr_mem, uint16_t io_base,
+                                 uint16_t io_len, bool enable_nvdimm)
 {
+    #define BASEPATH "\\_SB.PCI0." MEMORY_HOTPLUG_DEVICE "."
     int i;
     Aml *scope;
     Aml *crs;
@@ -1008,6 +1009,12 @@ static void build_memory_devices(Aml *sb_scope, int nr_mem,
     aml_append(field,
         /* initiates device eject, write only */
         aml_named_field(MEMORY_SLOT_EJECT, 1));
+
+    if (enable_nvdimm) {
+        aml_append(field,
+        /* initiates nvdimm device, read only */
+        aml_named_field(MEMORY_SLOT_NVDIMM, 1));
+    }
     aml_append(scope, field);
 
     field = aml_field(MEMORY_HOTPLUG_IO_REGION, AML_DWORD_ACC,
@@ -1022,7 +1029,6 @@ static void build_memory_devices(Aml *sb_scope, int nr_mem,
     aml_append(sb_scope, scope);
 
     for (i = 0; i < nr_mem; i++) {
-        #define BASEPATH "\\_SB.PCI0." MEMORY_HOTPLUG_DEVICE "."
         const char *s;
 
         dev = aml_device("MP%02X", i);
@@ -1067,6 +1073,17 @@ static void build_memory_devices(Aml *sb_scope, int nr_mem,
     method = aml_method(MEMORY_SLOT_NOTIFY_METHOD, 2, AML_NOTSERIALIZED);
     for (i = 0; i < nr_mem; i++) {
         ifctx = aml_if(aml_equal(aml_arg(0), aml_int(i)));
+
+        if (enable_nvdimm) {
+            Aml *ifnvdimm;
+
+            ifnvdimm = aml_if(aml_equal(aml_name(BASEPATH MEMORY_SLOT_NVDIMM),
+                                        aml_int(1)));
+            aml_append(ifnvdimm, aml_notify(aml_name("\\_SB.NVDR"),
+                                            aml_int(0x80)));
+            aml_append(ifctx, ifnvdimm);
+        }
+
         aml_append(ifctx,
             aml_notify(aml_name("MP%.02X", i), aml_arg(1))
         );
@@ -2223,7 +2240,8 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
     sb_scope = aml_scope("\\_SB");
     {
         build_memory_devices(sb_scope, nr_mem, pm->mem_hp_io_base,
-                             pm->mem_hp_io_len);
+                             pm->mem_hp_io_len,
+                             pcms->acpi_nvdimm_state.is_enabled);
 
         {
             Object *pci_host;
diff --git a/hw/mem/nvdimm.c b/hw/mem/nvdimm.c
index 28f5251..2f4b20e 100644
--- a/hw/mem/nvdimm.c
+++ b/hw/mem/nvdimm.c
@@ -154,13 +154,9 @@ static void nvdimm_prepare_unplug(DeviceState *dev)
 
 static void nvdimm_class_init(ObjectClass *oc, void *data)
 {
-    DeviceClass *dc = DEVICE_CLASS(oc);
     PCDIMMDeviceClass *ddc = PC_DIMM_CLASS(oc);
     NVDIMMClass *nvc = NVDIMM_CLASS(oc);
 
-    /* nvdimm hotplug has not been supported yet. */
-    dc->hotpluggable = false;
-
     ddc->realize = nvdimm_realize;
     ddc->get_memory_region = nvdimm_get_memory_region;
     ddc->get_vmstate_memory_region = nvdimm_get_vmstate_memory_region;
diff --git a/include/hw/acpi/pc-hotplug.h b/include/hw/acpi/pc-hotplug.h
index 6a8d268..a14977d 100644
--- a/include/hw/acpi/pc-hotplug.h
+++ b/include/hw/acpi/pc-hotplug.h
@@ -43,6 +43,7 @@
 #define MEMORY_SLOT_INSERT_EVENT     "MINS"
 #define MEMORY_SLOT_REMOVE_EVENT     "MRMV"
 #define MEMORY_SLOT_EJECT            "MEJ"
+#define MEMORY_SLOT_NVDIMM           "NVDM"
 #define MEMORY_SLOT_SLECTOR          "MSEL"
 #define MEMORY_SLOT_OST_EVENT        "MOEV"
 #define MEMORY_SLOT_OST_STATUS       "MOSC"
-- 
1.8.3.1