[Qemu-devel] [PATCH v4 23/33] nvdimm acpi: init the address region used by NVDIMM ACPI

[Xiao Guangrong]

We reserve the memory region 0xFF00000 ~ 0xFFF00000 for NVDIMM ACPI
which is used as:
- the first page is mapped as MMIO, ACPI write data to this page to
  transfer the control to QEMU

- the second page is RAM-based which used to save the input info of
  _DSM method and QEMU reuse it store output info

- the left is mapped as RAM, it's the buffer returned by _FIT method,
  this is needed by NVDIMM hotplug

Signed-off-by: Xiao Guangrong <address@hidden>
---
 hw/acpi/Makefile.objs   |   1 +
 hw/acpi/nvdimm.c        | 143 ++++++++++++++++++++++++++++++++++++++++++++++++
 hw/i386/pc.c            |   2 +
 include/hw/i386/pc.h    |   2 +
 include/hw/mem/nvdimm.h |  18 ++++++
 5 files changed, 166 insertions(+)
 create mode 100644 hw/acpi/nvdimm.c

diff --git a/hw/acpi/Makefile.objs b/hw/acpi/Makefile.objs
index 7d3230c..80426b4 100644
--- a/hw/acpi/Makefile.objs
+++ b/hw/acpi/Makefile.objs
@@ -2,6 +2,7 @@ common-obj-$(CONFIG_ACPI_X86) += core.o piix4.o pcihp.o
 common-obj-$(CONFIG_ACPI_X86_ICH) += ich9.o tco.o
 common-obj-$(CONFIG_ACPI_CPU_HOTPLUG) += cpu_hotplug.o
 common-obj-$(CONFIG_ACPI_MEMORY_HOTPLUG) += memory_hotplug.o
+common-obj-$(CONFIG_NVDIMM) += nvdimm.o
 common-obj-$(CONFIG_ACPI) += acpi_interface.o
 common-obj-$(CONFIG_ACPI) += bios-linker-loader.o
 common-obj-$(CONFIG_ACPI) += aml-build.o
diff --git a/hw/acpi/nvdimm.c b/hw/acpi/nvdimm.c
new file mode 100644
index 0000000..fd70de2
--- /dev/null
+++ b/hw/acpi/nvdimm.c
@@ -0,0 +1,143 @@
+/*
+ * NVDIMM ACPI Implementation
+ *
+ * Copyright(C) 2015 Intel Corporation.
+ *
+ * Author:
+ *  Xiao Guangrong <address@hidden>
+ *
+ * NFIT is defined in ACPI 6.0: 5.2.25 NVDIMM Firmware Interface Table (NFIT)
+ * and the DSM specification can be found at:
+ *       http://pmem.io/documents/NVDIMM_DSM_Interface_Example.pdf
+ *
+ * Currently, it only supports PMEM Virtualization.
+ *
+ * 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 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/>
+ */
+
+#include "qemu-common.h"
+#include "hw/acpi/acpi.h"
+#include "hw/acpi/aml-build.h"
+#include "hw/mem/nvdimm.h"
+
+/*
+ * System Physical Address Range Structure
+ *
+ * It describes the system physical address ranges occupied by NVDIMMs and
+ * the types of the regions.
+ */
+struct nfit_spa {
+    uint16_t type;
+    uint16_t length;
+    uint16_t spa_index;
+    uint16_t flags;
+    uint32_t reserved;
+    uint32_t proximity_domain;
+    uint8_t type_guid[16];
+    uint64_t spa_base;
+    uint64_t spa_length;
+    uint64_t mem_attr;
+} QEMU_PACKED;
+typedef struct nfit_spa nfit_spa;
+
+/*
+ * Memory Device to System Physical Address Range Mapping Structure
+ *
+ * It enables identifying each NVDIMM region and the corresponding SPA
+ * describing the memory interleave
+ */
+struct nfit_memdev {
+    uint16_t type;
+    uint16_t length;
+    uint32_t nfit_handle;
+    uint16_t phys_id;
+    uint16_t region_id;
+    uint16_t spa_index;
+    uint16_t dcr_index;
+    uint64_t region_len;
+    uint64_t region_offset;
+    uint64_t region_dpa;
+    uint16_t interleave_index;
+    uint16_t interleave_ways;
+    uint16_t flags;
+    uint16_t reserved;
+} QEMU_PACKED;
+typedef struct nfit_memdev nfit_memdev;
+
+/*
+ * NVDIMM Control Region Structure
+ *
+ * It describes the NVDIMM and if applicable, Block Control Window.
+ */
+struct nfit_dcr {
+    uint16_t type;
+    uint16_t length;
+    uint16_t dcr_index;
+    uint16_t vendor_id;
+    uint16_t device_id;
+    uint16_t revision_id;
+    uint16_t sub_vendor_id;
+    uint16_t sub_device_id;
+    uint16_t sub_revision_id;
+    uint8_t reserved[6];
+    uint32_t serial_number;
+    uint16_t fic;
+    uint16_t num_bcw;
+    uint64_t bcw_size;
+    uint64_t cmd_offset;
+    uint64_t cmd_size;
+    uint64_t status_offset;
+    uint64_t status_size;
+    uint16_t flags;
+    uint8_t reserved2[6];
+} QEMU_PACKED;
+typedef struct nfit_dcr nfit_dcr;
+
+/*
+ * calculate the size of structures which describe all NVDIMM devices.
+ * Currently each device has three structures as only PMEM is supported
+ * now.
+ */
+static uint64_t nvdimm_device_structure_size(uint64_t slots)
+{
+    return slots * (sizeof(nfit_spa) + sizeof(nfit_memdev) + sizeof(nfit_dcr));
+}
+
+/*
+ * calculate the size of the memory used to implement NVDIMM ACPI operations
+ * which include:
+ * - __DSM method: it needs two pages to transfer control and data between
+ *   Guest ACPI and QEMU.
+ *
+ * - _FIT method: it returns a buffer to Guest which contains the structures
+ *   describing all the present NVDIMM devices in the system.
+ */
+static uint64_t nvdimm_acpi_memory_size(uint64_t slots)
+{
+    uint64_t size = nvdimm_device_structure_size(slots);
+
+    return size + getpagesize() * 2;
+}
+
+void nvdimm_init_memory_state(NVDIMMState *state, MemoryRegion *system_memory,
+                              MachineState *machine)
+{
+    QEMU_BUILD_BUG_ON(nvdimm_acpi_memory_size(ACPI_MAX_RAM_SLOTS)
+                         >= NVDIMM_ACPI_MEM_SIZE);
+
+    state->base = NVDIMM_ACPI_MEM_BASE;
+    memory_region_init(&state->mr, OBJECT(machine), "nvdimm-acpi",
+                       NVDIMM_ACPI_MEM_SIZE);
+    memory_region_add_subregion(system_memory, state->base, &state->mr);
+}
diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 6694b18..2207e09 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -1360,6 +1360,8 @@ FWCfgState *pc_memory_init(PCMachineState *pcms,
             exit(EXIT_FAILURE);
         }
 
+        nvdimm_init_memory_state(&pcms->nvdimm_memory, system_memory, machine);
+
         pcms->hotplug_memory.base =
             ROUND_UP(0x100000000ULL + pcms->above_4g_mem_size, 1ULL << 30);
 
diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
index 693b6c5..fd65c27 100644
--- a/include/hw/i386/pc.h
+++ b/include/hw/i386/pc.h
@@ -17,6 +17,7 @@
 #include "hw/boards.h"
 #include "hw/compat.h"
 #include "hw/mem/dimm.h"
+#include "hw/mem/nvdimm.h"
 
 #define HPET_INTCAP "hpet-intcap"
 
@@ -32,6 +33,7 @@ struct PCMachineState {
 
     /* <public> */
     MemoryHotplugState hotplug_memory;
+    NVDIMMState nvdimm_memory;
 
     HotplugHandler *acpi_dev;
     ISADevice *rtc;
diff --git a/include/hw/mem/nvdimm.h b/include/hw/mem/nvdimm.h
index 60399d8..8e31983 100644
--- a/include/hw/mem/nvdimm.h
+++ b/include/hw/mem/nvdimm.h
@@ -33,6 +33,10 @@
  */
 #define MIN_NAMESPACE_LABEL_SIZE      (128UL << 10)
 
+/* Memory region 0xFF00000 ~ 0xFFF00000 is reserved for NVDIMM ACPI. */
+#define NVDIMM_ACPI_MEM_BASE          0xFF000000ULL
+#define NVDIMM_ACPI_MEM_SIZE          0xF00000ULL
+
 #define TYPE_NVDIMM      "nvdimm"
 #define NVDIMM(obj)      OBJECT_CHECK(NVDIMMDevice, (obj), TYPE_NVDIMM)
 
@@ -63,4 +67,18 @@ struct NVDIMMDevice {
 };
 typedef struct NVDIMMDevice NVDIMMDevice;
 
+/*
+ * NVDIMMState:
+ * @base: address in guest address space where NVDIMM ACPI memory begins.
+ * @mr: NVDIMM ACPI memory address space container.
+ */
+struct NVDIMMState {
+    ram_addr_t base;
+    MemoryRegion mr;
+};
+typedef struct NVDIMMState NVDIMMState;
+
+/* Initialize the memory region needed by NVDIMM ACPI.*/
+void nvdimm_init_memory_state(NVDIMMState *state, MemoryRegion *system_memory,
+                              MachineState *machine);
 #endif
-- 
1.8.3.1