[Qemu-devel] [PATCH 18/22] target-i386: move APIC to ICC bus

[Igor Mammedov <imammedo@redhat.com>]

... to allow it to be hotplugged

 * map APIC's mmio at board level if it is present

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
---
v2:
  * fix compile error "cpu may be used uninitialized"
     with --enable-werror but without --enable-debug.
---
 hw/apic_common.c   | 17 ++++++++++++-----
 hw/apic_internal.h |  6 +++---
 hw/i386/kvmvapic.c |  1 +
 hw/i386/pc.c       | 19 ++++++++++++++++---
 hw/icc_bus.c       | 15 ++++++++++++++-
 hw/icc_bus.h       |  3 ++-
 target-i386/cpu.c  | 16 +++-------------
 7 files changed, 51 insertions(+), 26 deletions(-)

diff --git a/hw/apic_common.c b/hw/apic_common.c
index 3798509..b2e84e6 100644
--- a/hw/apic_common.c
+++ b/hw/apic_common.c
@@ -21,6 +21,8 @@
 #include "hw/apic_internal.h"
 #include "trace.h"
 #include "sysemu/kvm.h"
+#include "qdev.h"
+#include "hw/sysbus.h"
 
 static int apic_irq_delivered;
 bool apic_report_tpr_access;
@@ -282,12 +284,14 @@ 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);
+    DeviceState *d = DEVICE(dev);
     APICCommonClass *info;
     static DeviceState *vapic;
     static int apic_no;
+    static bool mmio_registered;
 
     if (apic_no >= MAX_APICS) {
         return -1;
@@ -296,8 +300,11 @@ 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) {
+        MemoryRegion *as = ICC_BUS(d->parent_bus)->apic_address_space;
+        memory_region_add_subregion(as, 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 &&
@@ -375,7 +382,7 @@ static Property apic_properties_common[] = {
 
 static void apic_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);
 
     dc->vmsd = &vmstate_apic_common;
@@ -387,7 +394,7 @@ static void apic_common_class_init(ObjectClass *klass, void *data)
 
 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/hw/apic_internal.h b/hw/apic_internal.h
index aac6290..172fc91 100644
--- a/hw/apic_internal.h
+++ b/hw/apic_internal.h
@@ -21,7 +21,7 @@
 #define QEMU_APIC_INTERNAL_H
 
 #include "exec/memory.h"
-#include "hw/sysbus.h"
+#include "hw/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/hw/i386/kvmvapic.c b/hw/i386/kvmvapic.c
index c4be882..81e0a75 100644
--- a/hw/i386/kvmvapic.c
+++ b/hw/i386/kvmvapic.c
@@ -12,6 +12,7 @@
 #include "sysemu/cpus.h"
 #include "sysemu/kvm.h"
 #include "hw/apic_internal.h"
+#include "hw/sysbus.h"
 
 #define VAPIC_IO_PORT           0x7e
 
diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 9d617b4..7925a41 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -52,6 +52,7 @@
 #include "sysemu/arch_init.h"
 #include "qemu/bitmap.h"
 #include "qemu/config-file.h"
+#include "hw/icc_bus.h"
 
 /* debug PC/ISA interrupts */
 //#define DEBUG_IRQ
@@ -869,13 +870,13 @@ void pc_acpi_smi_interrupt(void *opaque, int irq, int level)
     }
 }
 
-static void pc_new_cpu(const char *cpu_model, int64_t apic_id, Error **errp)
+static X86CPU *pc_new_cpu(const char *cpu_model, int64_t apic_id, Error **errp)
 {
     X86CPU *cpu;
 
     cpu = cpu_x86_create(cpu_model, errp);
     if (!cpu) {
-        return;
+        return cpu;
     }
 
     object_property_set_int(OBJECT(cpu), apic_id, "apic-id", errp);
@@ -884,14 +885,18 @@ static void pc_new_cpu(const char *cpu_model, int64_t apic_id, Error **errp)
     if (error_is_set(errp)) {
         if (cpu != NULL) {
             object_unref(OBJECT(cpu));
+            cpu = NULL;
         }
     }
+    return cpu;
 }
 
 void pc_cpus_init(const char *cpu_model)
 {
     int i;
+    X86CPU *cpu = NULL;
     Error *error = NULL;
+    SysBusDevice *ib;
 
     /* init CPUs */
     if (cpu_model == NULL) {
@@ -902,14 +907,22 @@ void pc_cpus_init(const char *cpu_model)
 #endif
     }
 
+    ib = 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 it */
+    if (cpu && cpu->env.apic_state) {
+        sysbus_mmio_map_overlap(ib, 0, APIC_DEFAULT_ADDRESS, 0x1000);
+    }
 }
 
 void pc_acpi_init(const char *default_dsdt)
diff --git a/hw/icc_bus.c b/hw/icc_bus.c
index 7e75a0e..a0c4e02 100644
--- a/hw/icc_bus.c
+++ b/hw/icc_bus.c
@@ -59,13 +59,26 @@ static const TypeInfo icc_device_info = {
 
 typedef struct ICCBridgeState {
     SysBusDevice busdev;
+    MemoryRegion apic_container;
 } ICCBridgeState;
 #define ICC_BRIGDE(obj) OBJECT_CHECK(ICCBridgeState, (obj), TYPE_ICC_BRIDGE)
 
 
 static void icc_bridge_initfn(Object *obj)
 {
-    qbus_create(TYPE_ICC_BUS, DEVICE(obj), "icc-bus");
+    ICCBridgeState *s = ICC_BRIGDE(obj);
+    SysBusDevice *sb = SYS_BUS_DEVICE(obj);
+    ICCBus *ibus;
+
+    ibus = ICC_BUS(qbus_create(TYPE_ICC_BUS, DEVICE(obj), "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);
+    ibus->apic_address_space = &s->apic_container;
 }
 
 static const TypeInfo icc_bridge_info = {
diff --git a/hw/icc_bus.h b/hw/icc_bus.h
index f959a43..2c8f78f 100644
--- a/hw/icc_bus.h
+++ b/hw/icc_bus.h
@@ -19,6 +19,7 @@
 #ifndef ICC_BUS_H
 #define ICC_BUS_H
 
+#include "exec/memory.h"
 #include "hw/qdev-core.h"
 
 #define TYPE_ICC_BUS "icc-bus"
@@ -26,6 +27,7 @@
 #ifndef CONFIG_USER_ONLY
 typedef struct ICCBus {
     BusState qbus;
+    MemoryRegion *apic_address_space;
 } ICCBus;
 #define ICC_BUS(obj) OBJECT_CHECK(ICCBus, (obj), TYPE_ICC_BUS)
 
@@ -48,4 +50,3 @@ typedef struct ICCDeviceClass {
 
 #endif /* CONFIG_USER_ONLY */
 #endif
-
diff --git a/target-i386/cpu.c b/target-i386/cpu.c
index 2b3c1f3..32f7aea 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/icc_bus.h"
 #ifndef CONFIG_USER_ONLY
 #include "hw/xen.h"
-#include "hw/sysbus.h"
 #include "hw/apic_internal.h"
 #endif
 
@@ -2104,6 +2104,7 @@ 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";
 
@@ -2113,7 +2114,7 @@ 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(dev->parent_bus, apic_type);
     if (env->apic_state == NULL) {
         error_setg(errp, "APIC device '%s' could not be created", apic_type);
         return;
@@ -2130,7 +2131,6 @@ 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;
@@ -2141,16 +2141,6 @@ 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)
-- 
1.8.1.4