[Qemu-devel] [RFC PATCH 5/7] target-arm/cpu: Add apic_id property for ARMCPU

[Shannon Zhao]

Add apic_id property for ARMCPU. It can be used for cpu hotplug.

Signed-off-by: Shannon Zhao <address@hidden>
---
 target-arm/cpu-qom.h |    1 +
 target-arm/cpu.c     |   77 ++++++++++++++++++++++++++++++++++++++++++++++++++
 target-arm/cpu.h     |    2 +
 3 files changed, 80 insertions(+), 0 deletions(-)

diff --git a/target-arm/cpu-qom.h b/target-arm/cpu-qom.h
index ed5a644..d4560e2 100644
--- a/target-arm/cpu-qom.h
+++ b/target-arm/cpu-qom.h
@@ -59,6 +59,7 @@ typedef struct ARMCPU {
     /*< public >*/
 
     CPUARMState env;
+    uint32_t apic_id;
 
     /* Coprocessor information */
     GHashTable *cp_regs;
diff --git a/target-arm/cpu.c b/target-arm/cpu.c
index 285947f..9202b07 100644
--- a/target-arm/cpu.c
+++ b/target-arm/cpu.c
@@ -23,12 +23,17 @@
 #include "qemu-common.h"
 #include "hw/qdev-properties.h"
 #include "qapi/qmp/qerror.h"
+#include "qapi-visit.h"
+#include "qapi/visitor.h"
+#include "hw/acpi/topology.h"
+
 #if !defined(CONFIG_USER_ONLY)
 #include "hw/loader.h"
 #endif
 #include "hw/arm/arm.h"
 #include "sysemu/sysemu.h"
 #include "sysemu/kvm.h"
+#include "sysemu/cpus.h"
 #include "kvm_arm.h"
 
 static void arm_cpu_set_pc(CPUState *cs, vaddr value)
@@ -332,6 +337,65 @@ static inline void unset_feature(CPUARMState *env, int 
feature)
     env->features &= ~(1ULL << feature);
 }
 
+static void arm_cpuid_get_apic_id(Object *obj, Visitor *v, void *opaque,
+                                  const char *name, Error **errp)
+{
+    ARMCPU *cpu = ARM_CPU(obj);
+    int64_t value = cpu->apic_id;
+
+    visit_type_int(v, &value, name, errp);
+}
+
+static void arm_cpuid_set_apic_id(Object *obj, Visitor *v, void *opaque,
+                                  const char *name, Error **errp)
+{
+    ARMCPU *cpu = ARM_CPU(obj);
+    DeviceState *dev = DEVICE(obj);
+    const int64_t min = 0;
+    const int64_t max = UINT32_MAX;
+    Error *error = NULL;
+    int64_t value;
+
+    if (dev->realized) {
+        error_setg(errp, "Attempt to set property '%s' on '%s' after "
+                   "it was realized", name, object_get_typename(obj));
+        return;
+    }
+
+    visit_type_int(v, &value, name, &error);
+    if (error) {
+        error_propagate(errp, error);
+        return;
+    }
+    if (value < min || value > max) {
+        error_setg(errp, "Property %s.%s doesn't take value %" PRId64
+                   " (minimum: %" PRId64 ", maximum: %" PRId64 ")" ,
+                   object_get_typename(obj), name, value, min, max);
+        return;
+    }
+
+    if ((value != cpu->apic_id) && cpu_exists(value)) {
+        error_setg(errp, "CPU with APIC ID %" PRIi64 " exists", value);
+        return;
+    }
+    cpu->apic_id = value;
+}
+
+/* Calculates initial APIC ID for a specific CPU index
+ *
+ * Currently we need to be able to calculate the APIC ID from the CPU index
+ * alone (without requiring a CPU object), as the QEMU<->Seabios interfaces 
have
+ * no concept of "CPU index", and the NUMA tables on fw_cfg need the APIC ID of
+ * all CPUs up to max_cpus.
+ */
+uint32_t arm_cpu_apic_id_from_index(unsigned int cpu_index)
+{
+    uint32_t correct_id;
+
+    correct_id = apicid_from_cpu_idx(smp_cores, smp_threads, cpu_index);
+    return correct_id;
+}
+
 static void arm_cpu_initfn(Object *obj)
 {
     CPUState *cs = CPU(obj);
@@ -343,6 +407,11 @@ static void arm_cpu_initfn(Object *obj)
     cpu->cp_regs = g_hash_table_new_full(g_int_hash, g_int_equal,
                                          g_free, g_free);
 
+    object_property_add(obj, "apic-id", "int",
+                    arm_cpuid_get_apic_id,
+                    arm_cpuid_set_apic_id, NULL, NULL, NULL);
+
+     cpu->apic_id = arm_cpu_apic_id_from_index(cs->cpu_index);
 #ifndef CONFIG_USER_ONLY
     /* Our inbound IRQ and FIQ lines */
     if (kvm_enabled()) {
@@ -379,6 +448,13 @@ static void arm_cpu_initfn(Object *obj)
     }
 }
 
+static int64_t arm_cpu_get_arch_id(CPUState *cs)
+{
+    ARMCPU *cpu = ARM_CPU(cs);
+
+    return cpu->apic_id;
+}
+
 static Property arm_cpu_reset_cbar_property =
             DEFINE_PROP_UINT64("reset-cbar", ARMCPU, reset_cbar, 0);
 
@@ -1183,6 +1259,7 @@ static void arm_cpu_class_init(ObjectClass *oc, void 
*data)
     cc->set_pc = arm_cpu_set_pc;
     cc->gdb_read_register = arm_cpu_gdb_read_register;
     cc->gdb_write_register = arm_cpu_gdb_write_register;
+    cc->get_arch_id = arm_cpu_get_arch_id;
 #ifdef CONFIG_USER_ONLY
     cc->handle_mmu_fault = arm_cpu_handle_mmu_fault;
 #else
diff --git a/target-arm/cpu.h b/target-arm/cpu.h
index cd7a9e8..9e60972 100644
--- a/target-arm/cpu.h
+++ b/target-arm/cpu.h
@@ -1819,4 +1819,6 @@ enum {
     QEMU_PSCI_CONDUIT_HVC = 2,
 };
 
+uint32_t arm_cpu_apic_id_from_index(unsigned int cpu_index);
+
 #endif
-- 
1.7.1