[Qemu-devel] [PATCH 16/21] target-i386: move APIC to ICC bus

[Igor Mammedov <imammedo@redhat.com>]

It allows APIC to be hotplugged

 * map APIC's mmio at board level if it is present
 * do not register mmio region for each APIC, since
   only one is used/mapped

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
---
v2:
  * various style fixes
  * split out sysbus.h inclusion in kvmvapic.c to simplify review
  * squash pc_new_cpu() hunk into "introduce apic-id property" patch
    to simplify review
  * use qdev_get_parent_bus() to get icc-bus for apic
---
 hw/cpu/icc_bus.c                |   10 ++++++++++
 hw/i386/pc.c                    |   14 +++++++++++++-
 hw/intc/apic_common.c           |   18 ++++++++++++------
 include/hw/cpu/icc_bus.h        |    4 ++++
 include/hw/i386/apic_internal.h |    6 +++---
 target-i386/cpu.c               |   16 +++-------------
 6 files changed, 45 insertions(+), 23 deletions(-)

diff --git a/hw/cpu/icc_bus.c b/hw/cpu/icc_bus.c
index f6091b9..9715e07 100644
--- a/hw/cpu/icc_bus.c
+++ b/hw/cpu/icc_bus.c
@@ -75,6 +75,7 @@ typedef struct ICCBridgeState {
     /*< private >*/
     SysBusDevice parent_obj;
     ICCBus icc_bus;
+    MemoryRegion apic_container;
 } ICCBridgeState;
 
 #define ICC_BRIGDE(obj) OBJECT_CHECK(ICCBridgeState, (obj), TYPE_ICC_BRIDGE)
@@ -82,8 +83,17 @@ typedef struct ICCBridgeState {
 static void icc_bridge_init(Object *obj)
 {
     ICCBridgeState *s = ICC_BRIGDE(obj);
+    SysBusDevice *sb = SYS_BUS_DEVICE(obj);
 
     qbus_create_inplace(&s->icc_bus, TYPE_ICC_BUS, DEVICE(s), "icc-bus");
+
+    /* Do not change order of registering regions,
+     * APIC must be first registered region, board maps it by 0 index
+     */
+    memory_region_init(&s->apic_container, "icc-apic-container",
+                       APIC_SPACE_SIZE);
+    sysbus_init_mmio(sb, &s->apic_container);
+    s->icc_bus.apic_address_space = &s->apic_container;
 }
 
 static const TypeInfo icc_bridge_info = {
diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 30ec338..a09b7ee 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -53,6 +53,7 @@
 #include "qemu/bitmap.h"
 #include "qemu/config-file.h"
 #include "hw/acpi/acpi.h"
+#include "hw/cpu/icc_bus.h"
 
 /* debug PC/ISA interrupts */
 //#define DEBUG_IRQ
@@ -916,7 +917,9 @@ static X86CPU *pc_new_cpu(const char *cpu_model, int64_t apic_id, Error **errp)
 void pc_cpus_init(const char *cpu_model)
 {
     int i;
+    X86CPU *cpu = NULL;
     Error *error = NULL;
+    SysBusDevice *icc_bridge;
 
     /* init CPUs */
     if (cpu_model == NULL) {
@@ -927,14 +930,23 @@ void pc_cpus_init(const char *cpu_model)
 #endif
     }
 
+    icc_bridge = SYS_BUS_DEVICE(object_resolve_path_type("icc-bridge",
+                                                 TYPE_ICC_BRIDGE, NULL));
+
     for (i = 0; i < smp_cpus; i++) {
-        pc_new_cpu(cpu_model, x86_cpu_apic_id_from_index(i), &error);
+        cpu = pc_new_cpu(cpu_model, x86_cpu_apic_id_from_index(i), &error);
         if (error) {
             fprintf(stderr, "%s\n", error_get_pretty(error));
             error_free(error);
             exit(1);
         }
     }
+
+    /* map APIC MMIO area if CPU has APIC */
+    if (cpu && cpu->env.apic_state) {
+        /* XXX: what if the base changes? */
+        sysbus_mmio_map_overlap(icc_bridge, 0, APIC_DEFAULT_ADDRESS, 0x1000);
+    }
 }
 
 void pc_acpi_init(const char *default_dsdt)
diff --git a/hw/intc/apic_common.c b/hw/intc/apic_common.c
index e0ae07a..b03e904 100644
--- a/hw/intc/apic_common.c
+++ b/hw/intc/apic_common.c
@@ -21,6 +21,8 @@
 #include "hw/i386/apic_internal.h"
 #include "trace.h"
 #include "sysemu/kvm.h"
+#include "hw/qdev.h"
+#include "hw/sysbus.h"
 
 static int apic_irq_delivered;
 bool apic_report_tpr_access;
@@ -282,12 +284,13 @@ static int apic_load_old(QEMUFile *f, void *opaque, int version_id)
     return 0;
 }
 
-static int apic_init_common(SysBusDevice *dev)
+static int apic_init_common(ICCDevice *dev)
 {
     APICCommonState *s = APIC_COMMON(dev);
     APICCommonClass *info;
     static DeviceState *vapic;
     static int apic_no;
+    static bool mmio_registered;
 
     if (apic_no >= MAX_APICS) {
         return -1;
@@ -296,8 +299,11 @@ static int apic_init_common(SysBusDevice *dev)
 
     info = APIC_COMMON_GET_CLASS(s);
     info->init(s);
-
-    sysbus_init_mmio(dev, &s->io_memory);
+    if (!mmio_registered) {
+        ICCBus *b = ICC_BUS(qdev_get_parent_bus(DEVICE(dev)));
+        memory_region_add_subregion(b->apic_address_space, 0, &s->io_memory);
+        mmio_registered = true;
+    }
 
     /* Note: We need at least 1M to map the VAPIC option ROM */
     if (!vapic && s->vapic_control & VAPIC_ENABLE_MASK &&
@@ -375,19 +381,19 @@ static Property apic_properties_common[] = {
 
 static void apic_common_class_init(ObjectClass *klass, void *data)
 {
-    SysBusDeviceClass *sc = SYS_BUS_DEVICE_CLASS(klass);
+    ICCDeviceClass *idc = ICC_DEVICE_CLASS(klass);
     DeviceClass *dc = DEVICE_CLASS(klass);
 
     dc->vmsd = &vmstate_apic_common;
     dc->reset = apic_reset_common;
     dc->no_user = 1;
     dc->props = apic_properties_common;
-    sc->init = apic_init_common;
+    idc->init = apic_init_common;
 }
 
 static const TypeInfo apic_common_type = {
     .name = TYPE_APIC_COMMON,
-    .parent = TYPE_SYS_BUS_DEVICE,
+    .parent = TYPE_ICC_DEVICE,
     .instance_size = sizeof(APICCommonState),
     .class_size = sizeof(APICCommonClass),
     .class_init = apic_common_class_init,
diff --git a/include/hw/cpu/icc_bus.h b/include/hw/cpu/icc_bus.h
index a0abc21..53ef223 100644
--- a/include/hw/cpu/icc_bus.h
+++ b/include/hw/cpu/icc_bus.h
@@ -22,6 +22,7 @@
 #ifndef ICC_BUS_H
 #define ICC_BUS_H
 
+#include "exec/memory.h"
 #include "hw/qdev-core.h"
 
 #define TYPE_ICC_BUS "icc-bus"
@@ -31,6 +32,9 @@
 typedef struct ICCBus {
     /*< private >*/
     BusState parent_obj;
+
+    /*< public >*/
+    MemoryRegion *apic_address_space;
 } ICCBus;
 
 #define ICC_BUS(obj) OBJECT_CHECK(ICCBus, (obj), TYPE_ICC_BUS)
diff --git a/include/hw/i386/apic_internal.h b/include/hw/i386/apic_internal.h
index aac6290..1b0a7fb 100644
--- a/include/hw/i386/apic_internal.h
+++ b/include/hw/i386/apic_internal.h
@@ -21,7 +21,7 @@
 #define QEMU_APIC_INTERNAL_H
 
 #include "exec/memory.h"
-#include "hw/sysbus.h"
+#include "hw/cpu/icc_bus.h"
 #include "qemu/timer.h"
 
 /* APIC Local Vector Table */
@@ -78,7 +78,7 @@ typedef struct APICCommonState APICCommonState;
 
 typedef struct APICCommonClass
 {
-    SysBusDeviceClass parent_class;
+    ICCDeviceClass parent_class;
 
     void (*init)(APICCommonState *s);
     void (*set_base)(APICCommonState *s, uint64_t val);
@@ -92,7 +92,7 @@ typedef struct APICCommonClass
 } APICCommonClass;
 
 struct APICCommonState {
-    SysBusDevice busdev;
+    ICCDevice busdev;
 
     MemoryRegion io_memory;
     X86CPU *cpu;
diff --git a/target-i386/cpu.c b/target-i386/cpu.c
index 8d3ad00..c648ea7 100644
--- a/target-i386/cpu.c
+++ b/target-i386/cpu.c
@@ -41,10 +41,10 @@
 #endif
 
 #include "sysemu/sysemu.h"
+#include "hw/qdev-properties.h"
 #include "hw/cpu/icc_bus.h"
 #ifndef CONFIG_USER_ONLY
 #include "hw/xen/xen.h"
-#include "hw/sysbus.h"
 #include "hw/i386/apic_internal.h"
 #endif
 
@@ -2119,6 +2119,7 @@ static void mce_init(X86CPU *cpu)
 static void x86_cpu_apic_create(X86CPU *cpu, Error **errp)
 {
     CPUX86State *env = &cpu->env;
+    DeviceState *dev = DEVICE(cpu);
     APICCommonState *apic;
     const char *apic_type = "apic";
 
@@ -2128,7 +2129,7 @@ static void x86_cpu_apic_create(X86CPU *cpu, Error **errp)
         apic_type = "xen-apic";
     }
 
-    env->apic_state = qdev_try_create(NULL, apic_type);
+    env->apic_state = qdev_try_create(qdev_get_parent_bus(dev), apic_type);
     if (env->apic_state == NULL) {
         error_setg(errp, "APIC device '%s' could not be created", apic_type);
         return;
@@ -2145,7 +2146,6 @@ static void x86_cpu_apic_create(X86CPU *cpu, Error **errp)
 static void x86_cpu_apic_realize(X86CPU *cpu, Error **errp)
 {
     CPUX86State *env = &cpu->env;
-    static int apic_mapped;
 
     if (env->apic_state == NULL) {
         return;
@@ -2156,16 +2156,6 @@ static void x86_cpu_apic_realize(X86CPU *cpu, Error **errp)
                    object_get_typename(OBJECT(env->apic_state)));
         return;
     }
-
-    /* XXX: mapping more APICs at the same memory location */
-    if (apic_mapped == 0) {
-        /* NOTE: the APIC is directly connected to the CPU - it is not
-           on the global memory bus. */
-        /* XXX: what if the base changes? */
-        sysbus_mmio_map_overlap(SYS_BUS_DEVICE(env->apic_state), 0,
-                                APIC_DEFAULT_ADDRESS, 0x1000);
-        apic_mapped = 1;
-    }
 }
 #else
 static void x86_cpu_apic_realize(X86CPU *cpu, Error **errp)
-- 
1.7.1