pc: acpi-build: create memory hotplug IO region dynamically

it replaces a static complied in DSDT MMIO region
for memory hotplug with one created at runtime
leaving only truly static memory hotplug related
ASL bits in DSDT. And replaces template patching
of MEMORY_SLOTS_NUMBER value with ASL API created
named value.

Later it also would make easier to reuse current
ACPI memory hotplug on other targets.

Also later it would be possible to move remaining
memory hotplug ASL methods into build_ssdt() and
add all memory hotplug related AML into SSDT only
when memory hotplug is enabled, further reducing
ACPI tables blob if memory hotplug isn't used.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

3 files changed, 64 insertions, 31 deletions

diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index 377dd72ea6..98553f8acb 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -103,6 +103,8 @@ typedef struct AcpiPmInfo {
     uint32_t io_base;
     uint16_t cpu_hp_io_base;
     uint16_t cpu_hp_io_len;
+    uint16_t mem_hp_io_base;
+    uint16_t mem_hp_io_len;
 } AcpiPmInfo;
 
 typedef struct AcpiMiscInfo {
@@ -187,6 +189,9 @@ static void acpi_get_pm_info(AcpiPmInfo *pm)
     assert(obj);
 
     pm->cpu_hp_io_len = ACPI_GPE_PROC_LEN;
+    pm->mem_hp_io_base = ACPI_MEMORY_HOTPLUG_BASE;
+    pm->mem_hp_io_len = ACPI_MEMORY_HOTPLUG_IO_LEN;
+
     /* Fill in optional s3/s4 related properties */
     o = object_property_get_qobject(obj, ACPI_PM_PROP_S3_DISABLED, NULL);
     if (o) {
@@ -887,9 +892,6 @@ build_ssdt(GArray *table_data, GArray *linker,
 
     patch_pci_windows(pci, ssdt_ptr, sizeof(ssdp_misc_aml));
 
-    ACPI_BUILD_SET_LE(ssdt_ptr, sizeof(ssdp_misc_aml),
-                      ssdt_mctrl_nr_slots[0], 32, nr_mem);
-
     /*  create S3_ / S4_ / S5_ packages if necessary */
     scope = aml_scope("\\");
     if (!pm->s3_disabled) {
@@ -1027,6 +1029,55 @@ build_ssdt(GArray *table_data, GArray *linker,
 
         /* build memory devices */
         assert(nr_mem <= ACPI_MAX_RAM_SLOTS);
+        scope = aml_scope("\\_SB.PCI0." stringify(MEMORY_HOTPLUG_DEVICE));
+        aml_append(scope,
+            aml_name_decl(stringify(MEMORY_SLOTS_NUMBER), aml_int(nr_mem))
+        );
+
+        crs = aml_resource_template();
+        aml_append(crs,
+            aml_io(aml_decode16, pm->mem_hp_io_base, pm->mem_hp_io_base, 0,
+                   pm->mem_hp_io_len)
+        );
+        aml_append(scope, aml_name_decl("_CRS", crs));
+
+        aml_append(scope, aml_operation_region(
+            stringify(MEMORY_HOTPLUG_IO_REGION), aml_system_io,
+            pm->mem_hp_io_base, pm->mem_hp_io_len)
+        );
+
+        field = aml_field(stringify(MEMORY_HOTPLUG_IO_REGION), aml_dword_acc);
+        aml_append(field, /* read only */
+            aml_named_field(stringify(MEMORY_SLOT_ADDR_LOW), 32));
+        aml_append(field, /* read only */
+            aml_named_field(stringify(MEMORY_SLOT_ADDR_HIGH), 32));
+        aml_append(field, /* read only */
+            aml_named_field(stringify(MEMORY_SLOT_SIZE_LOW), 32));
+        aml_append(field, /* read only */
+            aml_named_field(stringify(MEMORY_SLOT_SIZE_HIGH), 32));
+        aml_append(field, /* read only */
+            aml_named_field(stringify(MEMORY_SLOT_PROXIMITY), 32));
+        aml_append(scope, field);
+
+        field = aml_field(stringify(MEMORY_HOTPLUG_IO_REGION), aml_byte_acc);
+        aml_append(field, aml_reserved_field(160 /* bits, Offset(20) */));
+        aml_append(field, /* 1 if enabled, read only */
+            aml_named_field(stringify(MEMORY_SLOT_ENABLED), 1));
+        aml_append(field,
+            /*(read) 1 if has a insert event. (write) 1 to clear event */
+            aml_named_field(stringify(MEMORY_SLOT_INSERT_EVENT), 1));
+        aml_append(scope, field);
+
+        field = aml_field(stringify(MEMORY_HOTPLUG_IO_REGION), aml_dword_acc);
+        aml_append(field, /* DIMM selector, write only */
+            aml_named_field(stringify(MEMORY_SLOT_SLECTOR), 32));
+        aml_append(field, /* _OST event code, write only */
+            aml_named_field(stringify(MEMORY_SLOT_OST_EVENT), 32));
+        aml_append(field, /* _OST status code, write only */
+            aml_named_field(stringify(MEMORY_SLOT_OST_STATUS), 32));
+        aml_append(scope, field);
+
+        aml_append(sb_scope, scope);
 
         for (i = 0; i < nr_mem; i++) {
             #define BASEPATH "\\_SB.PCI0." stringify(MEMORY_HOTPLUG_DEVICE) "."
diff --git a/hw/i386/acpi-dsdt-mem-hotplug.dsl b/hw/i386/acpi-dsdt-mem-hotplug.dsl
index 2a36c4799e..1e9ec39274 100644
--- a/hw/i386/acpi-dsdt-mem-hotplug.dsl
+++ b/hw/i386/acpi-dsdt-mem-hotplug.dsl
@@ -22,14 +22,16 @@
             External(MEMORY_SLOTS_NUMBER, IntObj)
 
             /* 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)
-            })
+            External(MEMORY_SLOT_ADDR_LOW, FieldUnitObj) // read only
+            External(MEMORY_SLOT_ADDR_HIGH, FieldUnitObj) // read only
+            External(MEMORY_SLOT_SIZE_LOW, FieldUnitObj) // read only
+            External(MEMORY_SLOT_SIZE_HIGH, FieldUnitObj) // read only
+            External(MEMORY_SLOT_PROXIMITY, FieldUnitObj) // read only
+            External(MEMORY_SLOT_ENABLED, FieldUnitObj) // 1 if enabled, read only
+            External(MEMORY_SLOT_INSERT_EVENT, FieldUnitObj) // (read) 1 if has a insert event. (write) 1 to clear event
+            External(MEMORY_SLOT_SLECTOR, FieldUnitObj) // DIMM selector, write only
+            External(MEMORY_SLOT_OST_EVENT, FieldUnitObj) // _OST event code, write only
+            External(MEMORY_SLOT_OST_STATUS, FieldUnitObj) // _OST status code, write only
 
             Method(_STA, 0) {
                 If (LEqual(MEMORY_SLOTS_NUMBER, Zero)) {
@@ -39,25 +41,7 @@
                 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)) {
diff --git a/hw/i386/ssdt-misc.dsl b/hw/i386/ssdt-misc.dsl
index 81be858b85..2588e30e19 100644
--- a/hw/i386/ssdt-misc.dsl
+++ b/hw/i386/ssdt-misc.dsl
@@ -36,7 +36,5 @@ DefinitionBlock ("ssdt-misc.aml", "SSDT", 0x01, "BXPC", "BXSSDTSUSP", 0x1)
        Name(P1E, Buffer() { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 })
        ACPI_EXTRACT_NAME_BUFFER8 acpi_pci64_length
        Name(P1L, Buffer() { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 })
-       ACPI_EXTRACT_NAME_DWORD_CONST ssdt_mctrl_nr_slots
-       Name(MEMORY_SLOTS_NUMBER, 0x12345678)
     }
 }