[Qemu-devel] [PATCH 15/16] target-i386: move IOAPIC to ICC bus

[Igor Mammedov <imammedo@redhat.com>]

 * inherit IOAPICs from ICCDevice and attach them to ICC bus
 * map IOAPIC's mmio at board level via indirect icc-bridge
   mmio region that provides address space to IOAPIC via
   icc-bus

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
---
 * do not create IOAPIC in icc-bridge and do not make it QOM child
   of icc-bridge, just attach it to icc-bus.
---
 hw/cpu/icc_bus.c                  |  6 ++++++
 hw/i386/kvm/ioapic.c              |  2 +-
 hw/i386/pc.c                      | 10 ++++++----
 hw/intc/ioapic_common.c           | 15 +++++++++++----
 include/exec/memory.h             | 10 ++++++++++
 include/hw/i386/icc_bus.h         |  1 +
 include/hw/i386/ioapic_internal.h |  6 +++---
 memory.c                          | 11 +++++++++++
 8 files changed, 49 insertions(+), 12 deletions(-)

diff --git a/hw/cpu/icc_bus.c b/hw/cpu/icc_bus.c
index 5078c38..d241438 100644
--- a/hw/cpu/icc_bus.c
+++ b/hw/cpu/icc_bus.c
@@ -63,6 +63,7 @@ static const TypeInfo icc_device_info = {
 typedef struct ICCBridgeState {
     SysBusDevice busdev;
     MemoryRegion apic_container;
+    MemoryRegion ioapic_container;
 } ICCBridgeState;
 #define ICC_BRIGDE(obj) OBJECT_CHECK(ICCBridgeState, (obj), TYPE_ICC_BRIDGE)
 
@@ -82,6 +83,11 @@ static void icc_bridge_initfn(Object *obj)
                        APIC_SPACE_SIZE);
     sysbus_init_mmio(sb, &s->apic_container);
     ibus->apic_address_space = &s->apic_container;
+
+    /* must be second registered region, board maps it by 1 index */
+    memory_region_init(&s->ioapic_container, "icc-ioapic-container", 0x1000);
+    sysbus_init_mmio(sb, &s->ioapic_container);
+    ibus->ioapic_address_space = &s->ioapic_container;
 }
 
 static const TypeInfo icc_bridge_info = {
diff --git a/hw/i386/kvm/ioapic.c b/hw/i386/kvm/ioapic.c
index a3bd519..b80d41a 100644
--- a/hw/i386/kvm/ioapic.c
+++ b/hw/i386/kvm/ioapic.c
@@ -96,7 +96,7 @@ static void kvm_ioapic_put(IOAPICCommonState *s)
 
     kioapic->id = s->id;
     kioapic->ioregsel = s->ioregsel;
-    kioapic->base_address = s->busdev.mmio[0].addr;
+    kioapic->base_address = memory_region_get_address(&s->io_memory);
     kioapic->irr = s->irr;
     for (i = 0; i < IOAPIC_NUM_PINS; i++) {
         kioapic->redirtbl[i].bits = s->ioredtbl[i];
diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 31b5294..a5c19a2 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -1217,20 +1217,22 @@ void ioapic_init_gsi(GSIState *gsi_state, const char *parent_name)
     DeviceState *dev;
     SysBusDevice *d;
     unsigned int i;
+    BusState *b = BUS(object_resolve_path_type("icc-bus", TYPE_ICC_BUS, NULL));
 
     if (kvm_irqchip_in_kernel()) {
-        dev = qdev_create(NULL, "kvm-ioapic");
+        dev = qdev_create(b, "kvm-ioapic");
     } else {
-        dev = qdev_create(NULL, "ioapic");
+        dev = qdev_create(b, "ioapic");
     }
     if (parent_name) {
         object_property_add_child(object_resolve_path(parent_name, NULL),
                                   "ioapic", OBJECT(dev), NULL);
     }
     qdev_init_nofail(dev);
-    d = SYS_BUS_DEVICE(dev);
-    sysbus_mmio_map(d, 0, IO_APIC_DEFAULT_ADDRESS);
 
+    d = SYS_BUS_DEVICE(object_resolve_path_type("icc-bridge", TYPE_ICC_BRIDGE,
+                                                NULL));
+    sysbus_mmio_map(d, 1, IO_APIC_DEFAULT_ADDRESS);
     for (i = 0; i < IOAPIC_NUM_PINS; i++) {
         gsi_state->ioapic_irq[i] = qdev_get_gpio_in(dev, i);
     }
diff --git a/hw/intc/ioapic_common.c b/hw/intc/ioapic_common.c
index 5c5bb3c..72c48a8 100644
--- a/hw/intc/ioapic_common.c
+++ b/hw/intc/ioapic_common.c
@@ -57,11 +57,13 @@ static int ioapic_dispatch_post_load(void *opaque, int version_id)
     return 0;
 }
 
-static int ioapic_init_common(SysBusDevice *dev)
+static int ioapic_init_common(ICCDevice *dev)
 {
     IOAPICCommonState *s = IOAPIC_COMMON(dev);
+    DeviceState *d = DEVICE(dev);
     IOAPICCommonClass *info;
     static int ioapic_no;
+    static bool mmio_registered;
 
     if (ioapic_no >= MAX_IOAPICS) {
         return -1;
@@ -70,7 +72,12 @@ static int ioapic_init_common(SysBusDevice *dev)
     info = IOAPIC_COMMON_GET_CLASS(s);
     info->init(s, ioapic_no);
 
-    sysbus_init_mmio(&s->busdev, &s->io_memory);
+    if (!mmio_registered) {
+        MemoryRegion *as = ICC_BUS(d->parent_bus)->ioapic_address_space;
+        memory_region_add_subregion(as, 0, &s->io_memory);
+        mmio_registered = true;
+    }
+
     ioapic_no++;
 
     return 0;
@@ -95,7 +102,7 @@ static const VMStateDescription vmstate_ioapic_common = {
 
 static void ioapic_common_class_init(ObjectClass *klass, void *data)
 {
-    SysBusDeviceClass *sc = SYS_BUS_DEVICE_CLASS(klass);
+    ICCDeviceClass *sc = ICC_DEVICE_CLASS(klass);
     DeviceClass *dc = DEVICE_CLASS(klass);
 
     sc->init = ioapic_init_common;
@@ -105,7 +112,7 @@ static void ioapic_common_class_init(ObjectClass *klass, void *data)
 
 static const TypeInfo ioapic_common_type = {
     .name = TYPE_IOAPIC_COMMON,
-    .parent = TYPE_SYS_BUS_DEVICE,
+    .parent = TYPE_ICC_DEVICE,
     .instance_size = sizeof(IOAPICCommonState),
     .class_size = sizeof(IOAPICCommonClass),
     .class_init = ioapic_common_class_init,
diff --git a/include/exec/memory.h b/include/exec/memory.h
index 2322732..826e401 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -711,6 +711,16 @@ void memory_region_set_enabled(MemoryRegion *mr, bool enabled);
 void memory_region_set_address(MemoryRegion *mr, hwaddr addr);
 
 /*
+ * memory_region_get_address: get current the address of a region
+ *
+ * Returns the absolute address of a region.
+ * May be used on regions that are currently part of a memory hierarchy.
+ *
+ * @mr: the region being queried
+ */
+hwaddr memory_region_get_address(MemoryRegion *mr);
+
+/*
  * memory_region_set_alias_offset: dynamically update a memory alias's offset
  *
  * Dynamically updates the offset into the target region that an alias points
diff --git a/include/hw/i386/icc_bus.h b/include/hw/i386/icc_bus.h
index 1b07619..d92c6ab 100644
--- a/include/hw/i386/icc_bus.h
+++ b/include/hw/i386/icc_bus.h
@@ -31,6 +31,7 @@
 typedef struct ICCBus {
     BusState qbus;
     MemoryRegion *apic_address_space;
+    MemoryRegion *ioapic_address_space;
 } ICCBus;
 #define ICC_BUS(obj) OBJECT_CHECK(ICCBus, (obj), TYPE_ICC_BUS)
 
diff --git a/include/hw/i386/ioapic_internal.h b/include/hw/i386/ioapic_internal.h
index 25576c8..4768c5b 100644
--- a/include/hw/i386/ioapic_internal.h
+++ b/include/hw/i386/ioapic_internal.h
@@ -24,7 +24,7 @@
 
 #include "hw/hw.h"
 #include "exec/memory.h"
-#include "hw/sysbus.h"
+#include "hw/i386/icc_bus.h"
 
 #define MAX_IOAPICS                     1
 
@@ -82,14 +82,14 @@ typedef struct IOAPICCommonState IOAPICCommonState;
      OBJECT_GET_CLASS(IOAPICCommonClass, (obj), TYPE_IOAPIC_COMMON)
 
 typedef struct IOAPICCommonClass {
-    SysBusDeviceClass parent_class;
+    ICCDeviceClass parent_class;
     void (*init)(IOAPICCommonState *s, int instance_no);
     void (*pre_save)(IOAPICCommonState *s);
     void (*post_load)(IOAPICCommonState *s);
 } IOAPICCommonClass;
 
 struct IOAPICCommonState {
-    SysBusDevice busdev;
+    ICCDevice busdev;
     MemoryRegion io_memory;
     uint8_t id;
     uint8_t ioregsel;
diff --git a/memory.c b/memory.c
index 75ca281..0651050 100644
--- a/memory.c
+++ b/memory.c
@@ -1413,6 +1413,17 @@ void memory_region_set_address(MemoryRegion *mr, hwaddr addr)
     memory_region_transaction_commit();
 }
 
+hwaddr memory_region_get_address(MemoryRegion *mr)
+{
+    hwaddr addr = mr->addr;
+
+    while (mr->parent) {
+        mr = mr->parent;
+        addr += mr->addr;
+    }
+    return addr;
+}
+
 void memory_region_set_alias_offset(MemoryRegion *mr, hwaddr offset)
 {
     assert(mr->alias);
-- 
1.8.2