pc: ACPI BIOS: implement memory hotplug interface

- provides static SSDT object for memory hotplug that can handle
  upto 256 hotplugable memory slots
- SSDT template for memory devices and runtime generator
  of them in SSDT table.

Signed-off-by: Vasilis Liaskovitis <vasilis.liaskovitis@profitbricks.com>
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Acked-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

5 files changed, 299 insertions, 1 deletions

diff --git a/hw/i386/Makefile.objs b/hw/i386/Makefile.objs
index f66c349..a65473c 100644
--- a/hw/i386/Makefile.objs
+++ b/hw/i386/Makefile.objs
@@ -9,7 +9,8 @@ obj-y += acpi-build.o
 obj-y += bios-linker-loader.o
 hw/i386/acpi-build.o: hw/i386/acpi-build.c hw/i386/acpi-dsdt.hex \
 	hw/i386/ssdt-proc.hex hw/i386/ssdt-pcihp.hex hw/i386/ssdt-misc.hex \
-	hw/i386/acpi-dsdt.hex hw/i386/q35-acpi-dsdt.hex
+	hw/i386/acpi-dsdt.hex hw/i386/q35-acpi-dsdt.hex \
+	hw/i386/q35-acpi-dsdt.hex hw/i386/ssdt-mem.hex
 
 iasl-option=$(shell if test -z "`$(1) $(2) 2>&1 > /dev/null`" \
     ; then echo "$(2)"; else echo "$(3)"; fi ;)
diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index 9a41510..6ff7fa3 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -37,6 +37,7 @@
 #include "bios-linker-loader.h"
 #include "hw/loader.h"
 #include "hw/isa/isa.h"
+#include "hw/acpi/memory_hotplug.h"
 
 /* Supported chipsets: */
 #include "hw/acpi/piix4.h"
@@ -667,6 +668,14 @@ static inline char acpi_get_hex(uint32_t val)
 #define ACPI_PCIQXL_SIZEOF (*ssdt_pciqxl_end - *ssdt_pciqxl_start)
 #define ACPI_PCIQXL_AML (ssdp_pcihp_aml + *ssdt_pciqxl_start)
 
+#include "hw/i386/ssdt-mem.hex"
+
+/* 0x5B 0x82 DeviceOp PkgLength NameString DimmID */
+#define ACPI_MEM_OFFSET_HEX (*ssdt_mem_name - *ssdt_mem_start + 2)
+#define ACPI_MEM_OFFSET_ID (*ssdt_mem_id - *ssdt_mem_start + 7)
+#define ACPI_MEM_SIZEOF (*ssdt_mem_end - *ssdt_mem_start)
+#define ACPI_MEM_AML (ssdm_mem_aml + *ssdt_mem_start)
+
 #define ACPI_SSDT_SIGNATURE 0x54445353 /* SSDT */
 #define ACPI_SSDT_HEADER_LENGTH 36
 
@@ -1003,6 +1012,8 @@ build_ssdt(GArray *table_data, GArray *linker,
            AcpiCpuInfo *cpu, AcpiPmInfo *pm, AcpiMiscInfo *misc,
            PcPciInfo *pci, PcGuestInfo *guest_info)
 {
+    MachineState *machine = MACHINE(qdev_get_machine());
+    uint32_t nr_mem = machine->ram_slots;
     unsigned acpi_cpus = guest_info->apic_id_limit;
     int ssdt_start = table_data->len;
     uint8_t *ssdt_ptr;
@@ -1031,6 +1042,9 @@ build_ssdt(GArray *table_data, GArray *linker,
     ACPI_BUILD_SET_LE(ssdt_ptr, sizeof(ssdp_misc_aml),
                       ssdt_isa_pest[0], 16, misc->pvpanic_port);
 
+    ACPI_BUILD_SET_LE(ssdt_ptr, sizeof(ssdp_misc_aml),
+                      ssdt_mctrl_nr_slots[0], 32, nr_mem);
+
     {
         GArray *sb_scope = build_alloc_array();
         uint8_t op = 0x10; /* ScopeOp */
@@ -1084,6 +1098,27 @@ build_ssdt(GArray *table_data, GArray *linker,
             build_free_array(package);
         }
 
+        if (nr_mem) {
+            assert(nr_mem <= ACPI_MAX_RAM_SLOTS);
+            /* build memory devices */
+            for (i = 0; i < nr_mem; i++) {
+                char id[3];
+                uint8_t *mem = acpi_data_push(sb_scope, ACPI_MEM_SIZEOF);
+
+                snprintf(id, sizeof(id), "%02X", i);
+                memcpy(mem, ACPI_MEM_AML, ACPI_MEM_SIZEOF);
+                memcpy(mem + ACPI_MEM_OFFSET_HEX, id, 2);
+                memcpy(mem + ACPI_MEM_OFFSET_ID, id, 2);
+            }
+
+            /* build Method(MEMORY_SLOT_NOTIFY_METHOD, 2) {
+             *     If (LEqual(Arg0, 0x00)) {Notify(MP00, Arg1)} ...
+             */
+            build_append_notify_method(sb_scope,
+                                       stringify(MEMORY_SLOT_NOTIFY_METHOD),
+                                       "MP%0.02X", nr_mem);
+        }
+
         {
             AcpiBuildPciBusHotplugState hotplug_state;
             Object *pci_host;
diff --git a/hw/i386/ssdt-mem.dsl b/hw/i386/ssdt-mem.dsl
new file mode 100644
index 0000000..8e17bd1
--- /dev/null
+++ b/hw/i386/ssdt-mem.dsl
@@ -0,0 +1,77 @@
+/*
+ * Memory hotplug ACPI DSDT static objects definitions
+ *
+ * Copyright ProfitBricks GmbH 2012
+ * Copyright (C) 2013-2014 Red Hat Inc
+ *
+ * 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/>
+ */
+
+/* This file is the basis for the ssdt_mem[] variable in src/acpi.c.
+ * It defines the contents of the memory device object.  At
+ * runtime, a dynamically generated SSDT will contain one copy of this
+ * AML snippet for every possible memory device in the system.  The
+ * objects will be placed in the \_SB_ namespace.
+ *
+ * In addition to the aml code generated from this file, the
+ * src/acpi.c file creates a MTFY method with an entry for each memdevice:
+ *     Method(MTFY, 2) {
+ *         If (LEqual(Arg0, 0x00)) { Notify(MP00, Arg1) }
+ *         If (LEqual(Arg0, 0x01)) { Notify(MP01, Arg1) }
+ *         ...
+ *     }
+ */
+#include "hw/acpi/pc-hotplug.h"
+
+ACPI_EXTRACT_ALL_CODE ssdm_mem_aml
+
+DefinitionBlock ("ssdt-mem.aml", "SSDT", 0x02, "BXPC", "CSSDT", 0x1)
+{
+
+    External(\_SB.PCI0.MEMORY_HOPTLUG_DEVICE.MEMORY_SLOT_CRS_METHOD, MethodObj)
+    External(\_SB.PCI0.MEMORY_HOPTLUG_DEVICE.MEMORY_SLOT_STATUS_METHOD, MethodObj)
+    External(\_SB.PCI0.MEMORY_HOPTLUG_DEVICE.MEMORY_SLOT_OST_METHOD, MethodObj)
+    External(\_SB.PCI0.MEMORY_HOPTLUG_DEVICE.MEMORY_SLOT_PROXIMITY_METHOD, MethodObj)
+
+    Scope(\_SB) {
+/*  v------------------ DO NOT EDIT ------------------v */
+        ACPI_EXTRACT_DEVICE_START ssdt_mem_start
+        ACPI_EXTRACT_DEVICE_END ssdt_mem_end
+        ACPI_EXTRACT_DEVICE_STRING ssdt_mem_name
+        Device(MPAA) {
+            ACPI_EXTRACT_NAME_STRING ssdt_mem_id
+            Name(_UID, "0xAA")
+/*  ^------------------ DO NOT EDIT ------------------^
+ * Don't change the above without also updating the C code.
+ */
+            Name(_HID, EISAID("PNP0C80"))
+
+            Method(_CRS, 0) {
+                Return(\_SB.PCI0.MEMORY_HOPTLUG_DEVICE.MEMORY_SLOT_CRS_METHOD(_UID))
+            }
+
+            Method(_STA, 0) {
+                Return(\_SB.PCI0.MEMORY_HOPTLUG_DEVICE.MEMORY_SLOT_STATUS_METHOD(_UID))
+            }
+
+            Method(_PXM, 0) {
+                Return(\_SB.PCI0.MEMORY_HOPTLUG_DEVICE.MEMORY_SLOT_PROXIMITY_METHOD(_UID))
+            }
+
+            Method(_OST, 3) {
+                \_SB.PCI0.MEMORY_HOPTLUG_DEVICE.MEMORY_SLOT_OST_METHOD(_UID, Arg0, Arg1, Arg2)
+            }
+        }
+    }
+}
diff --git a/hw/i386/ssdt-misc.dsl b/hw/i386/ssdt-misc.dsl
index a4484b8..d329b8b 100644
--- a/hw/i386/ssdt-misc.dsl
+++ b/hw/i386/ssdt-misc.dsl
@@ -12,6 +12,7 @@
  * You should have received a copy of the GNU General Public License along
  * with this program; if not, see <http://www.gnu.org/licenses/>.
  */
+#include "hw/acpi/pc-hotplug.h"
 
 ACPI_EXTRACT_ALL_CODE ssdp_misc_aml
 
@@ -116,4 +117,167 @@ DefinitionBlock ("ssdt-misc.aml", "SSDT", 0x01, "BXPC", "BXSSDTSUSP", 0x1)
             }
         }
     }
+
+    External(MEMORY_SLOT_NOTIFY_METHOD, MethodObj)
+    Scope(\_SB.PCI0) {
+        Device(MEMORY_HOPTLUG_DEVICE) {
+            Name(_HID, "PNP0A06")
+            Name(_UID, "Memory hotplug resources")
+
+            ACPI_EXTRACT_NAME_DWORD_CONST ssdt_mctrl_nr_slots
+            Name(MEMORY_SLOTS_NUMBER, 0x12345678)
+
+            /* Memory hotplug IO registers */
+            OperationRegion(MEMORY_HOTPLUG_IO_REGION, SystemIO,
+                            ACPI_MEMORY_HOTPLUG_BASE,
+                            ACPI_MEMORY_HOTPLUG_IO_LEN)
+
+            Name(_CRS, ResourceTemplate() {
+                IO(Decode16, ACPI_MEMORY_HOTPLUG_BASE, ACPI_MEMORY_HOTPLUG_BASE,
+                   0, ACPI_MEMORY_HOTPLUG_IO_LEN, IO)
+            })
+
+            Method(_STA, 0) {
+                If (LEqual(MEMORY_SLOTS_NUMBER, Zero)) {
+                    Return(0x0)
+                }
+                /* present, functioning, decoding, not shown in UI */
+                Return(0xB)
+            }
+
+            Field(MEMORY_HOTPLUG_IO_REGION, DWordAcc, NoLock, Preserve) {
+                MEMORY_SLOT_ADDR_LOW, 32,  // read only
+                MEMORY_SLOT_ADDR_HIGH, 32, // read only
+                MEMORY_SLOT_SIZE_LOW, 32,  // read only
+                MEMORY_SLOT_SIZE_HIGH, 32, // read only
+                MEMORY_SLOT_PROXIMITY, 32, // read only
+            }
+            Field(MEMORY_HOTPLUG_IO_REGION, ByteAcc, NoLock, Preserve) {
+                Offset(20),
+                MEMORY_SLOT_ENABLED,  1, // 1 if enabled, read only
+                MEMORY_SLOT_INSERT_EVENT, 1, // (read) 1 if has a insert event. (write) 1 to clear event
+            }
+
+            Mutex (MEMORY_SLOT_LOCK, 0)
+            Field (MEMORY_HOTPLUG_IO_REGION, DWordAcc, NoLock, Preserve) {
+                MEMORY_SLOT_SLECTOR, 32,  // DIMM selector, write only
+                MEMORY_SLOT_OST_EVENT, 32,  // _OST event code, write only
+                MEMORY_SLOT_OST_STATUS, 32,  // _OST status code, write only
+            }
+
+            Method(MEMORY_SLOT_SCAN_METHOD, 0) {
+                If (LEqual(MEMORY_SLOTS_NUMBER, Zero)) {
+                     Return(Zero)
+                }
+
+                Store(Zero, Local0) // Mem devs iterrator
+                Acquire(MEMORY_SLOT_LOCK, 0xFFFF)
+                while (LLess(Local0, MEMORY_SLOTS_NUMBER)) {
+                    Store(Local0, MEMORY_SLOT_SLECTOR) // select Local0 DIMM
+                    If (LEqual(MEMORY_SLOT_INSERT_EVENT, One)) { // Memory device needs check
+                        MEMORY_SLOT_NOTIFY_METHOD(Local0, 1)
+                        Store(1, MEMORY_SLOT_INSERT_EVENT)
+                    }
+                    // TODO: handle memory eject request
+                    Add(Local0, One, Local0) // goto next DIMM
+                }
+                Release(MEMORY_SLOT_LOCK)
+                Return(One)
+            }
+
+            Method(MEMORY_SLOT_STATUS_METHOD, 1) {
+                Store(Zero, Local0)
+
+                Acquire(MEMORY_SLOT_LOCK, 0xFFFF)
+                Store(ToInteger(Arg0), MEMORY_SLOT_SLECTOR) // select DIMM
+
+                If (LEqual(MEMORY_SLOT_ENABLED, One)) {
+                    Store(0xF, Local0)
+                }
+
+                Release(MEMORY_SLOT_LOCK)
+                Return(Local0)
+            }
+
+            Method(MEMORY_SLOT_CRS_METHOD, 1, Serialized) {
+                Acquire(MEMORY_SLOT_LOCK, 0xFFFF)
+                Store(ToInteger(Arg0), MEMORY_SLOT_SLECTOR) // select DIMM
+
+                Name(MR64, ResourceTemplate() {
+                    QWordMemory(ResourceProducer, PosDecode, MinFixed, MaxFixed,
+                    Cacheable, ReadWrite,
+                    0x0000000000000000,        // Address Space Granularity
+                    0x0000000000000000,        // Address Range Minimum
+                    0xFFFFFFFFFFFFFFFE,        // Address Range Maximum
+                    0x0000000000000000,        // Address Translation Offset
+                    0xFFFFFFFFFFFFFFFF,        // Address Length
+                    ,, MW64, AddressRangeMemory, TypeStatic)
+                })
+
+                CreateDWordField(MR64, 14, MINL)
+                CreateDWordField(MR64, 18, MINH)
+                CreateDWordField(MR64, 38, LENL)
+                CreateDWordField(MR64, 42, LENH)
+                CreateDWordField(MR64, 22, MAXL)
+                CreateDWordField(MR64, 26, MAXH)
+
+                Store(MEMORY_SLOT_ADDR_HIGH, MINH)
+                Store(MEMORY_SLOT_ADDR_LOW, MINL)
+                Store(MEMORY_SLOT_SIZE_HIGH, LENH)
+                Store(MEMORY_SLOT_SIZE_LOW, LENL)
+
+                // 64-bit math: MAX = MIN + LEN - 1
+                Add(MINL, LENL, MAXL)
+                Add(MINH, LENH, MAXH)
+                If (LLess(MAXL, MINL)) {
+                    Add(MAXH, One, MAXH)
+                }
+                If (LLess(MAXL, One)) {
+                    Subtract(MAXH, One, MAXH)
+                }
+                Subtract(MAXL, One, MAXL)
+
+                If (LEqual(MAXH, Zero)){
+                    Name(MR32, ResourceTemplate() {
+                        DWordMemory(ResourceProducer, PosDecode, MinFixed, MaxFixed,
+                        Cacheable, ReadWrite,
+                        0x00000000,        // Address Space Granularity
+                        0x00000000,        // Address Range Minimum
+                        0xFFFFFFFE,        // Address Range Maximum
+                        0x00000000,        // Address Translation Offset
+                        0xFFFFFFFF,        // Address Length
+                        ,, MW32, AddressRangeMemory, TypeStatic)
+                    })
+                    CreateDWordField(MR32, MW32._MIN, MIN)
+                    CreateDWordField(MR32, MW32._MAX, MAX)
+                    CreateDWordField(MR32, MW32._LEN, LEN)
+                    Store(MINL, MIN)
+                    Store(MAXL, MAX)
+                    Store(LENL, LEN)
+
+                    Release(MEMORY_SLOT_LOCK)
+                    Return(MR32)
+                }
+
+                Release(MEMORY_SLOT_LOCK)
+                Return(MR64)
+            }
+
+            Method(MEMORY_SLOT_PROXIMITY_METHOD, 1) {
+                Acquire(MEMORY_SLOT_LOCK, 0xFFFF)
+                Store(ToInteger(Arg0), MEMORY_SLOT_SLECTOR) // select DIMM
+                Store(MEMORY_SLOT_PROXIMITY, Local0)
+                Release(MEMORY_SLOT_LOCK)
+                Return(Local0)
+            }
+
+            Method(MEMORY_SLOT_OST_METHOD, 4) {
+                Acquire(MEMORY_SLOT_LOCK, 0xFFFF)
+                Store(ToInteger(Arg0), MEMORY_SLOT_SLECTOR) // select DIMM
+                Store(Arg1, MEMORY_SLOT_OST_EVENT)
+                Store(Arg2, MEMORY_SLOT_OST_STATUS)
+                Release(MEMORY_SLOT_LOCK)
+            }
+        } // Device()
+    } // Scope()
 }
diff --git a/include/hw/acpi/pc-hotplug.h b/include/hw/acpi/pc-hotplug.h
index 01d38e2..bf5157d 100644
--- a/include/hw/acpi/pc-hotplug.h
+++ b/include/hw/acpi/pc-hotplug.h
@@ -32,4 +32,25 @@
 #define ACPI_MEMORY_HOTPLUG_IO_LEN 24
 #define ACPI_MEMORY_HOTPLUG_BASE 0x0a00
 
+#define MEMORY_HOPTLUG_DEVICE        MHPD
+#define MEMORY_SLOTS_NUMBER          MDNR
+#define MEMORY_HOTPLUG_IO_REGION     HPMR
+#define MEMORY_SLOT_ADDR_LOW         MRBL
+#define MEMORY_SLOT_ADDR_HIGH        MRBH
+#define MEMORY_SLOT_SIZE_LOW         MRLL
+#define MEMORY_SLOT_SIZE_HIGH        MRLH
+#define MEMORY_SLOT_PROXIMITY        MPX
+#define MEMORY_SLOT_ENABLED          MES
+#define MEMORY_SLOT_INSERT_EVENT     MINS
+#define MEMORY_SLOT_SLECTOR          MSEL
+#define MEMORY_SLOT_OST_EVENT        MOEV
+#define MEMORY_SLOT_OST_STATUS       MOSC
+#define MEMORY_SLOT_LOCK             MLCK
+#define MEMORY_SLOT_STATUS_METHOD    MRST
+#define MEMORY_SLOT_CRS_METHOD       MCRS
+#define MEMORY_SLOT_OST_METHOD       MOST
+#define MEMORY_SLOT_PROXIMITY_METHOD MPXM
+#define MEMORY_SLOT_NOTIFY_METHOD    MTFY
+#define MEMORY_SLOT_SCAN_METHOD      MSCN
+
 #endif