---
 debug/mcdstub/mcdstub.c | 154 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 154 insertions(+)

diff --git a/debug/mcdstub/mcdstub.c b/debug/mcdstub/mcdstub.c
index 32f4d1980f..176d5d2311 100644
--- a/debug/mcdstub/mcdstub.c
+++ b/debug/mcdstub/mcdstub.c
@@ -22,9 +22,12 @@
 #include "qemu/cutils.h"
 #include "qemu/module.h"
 #include "qemu/error-report.h"
+#include "qemu/debug.h"
 #include "qapi/error.h"
 #include "chardev/char.h"
 #include "chardev/char-fe.h"
+#include "hw/cpu/cluster.h"
+#include "hw/boards.h"
 #include "sysemu/cpus.h"
 #include "sysemu/hw_accel.h"
 #include "sysemu/runstate.h"
@@ -109,6 +112,39 @@ static void mcd_chr_event(void *opaque, QEMUChrEvent event)
 {
 }
 
+/**
+ * init_query_cmds_table() - Initializes all query functions.
+ *
+ * This function adds all query functions to the mcd_query_cmds_table. This
+ * includes their command string, handler function and parameter schema.
+ * @mcd_query_cmds_table: Lookup table with all query commands.
+ */
+static void init_query_cmds_table(MCDCmdParseEntry *mcd_query_cmds_table)
+{}
+
+/**
+ * mcd_set_stop_cpu() - Sets c_cpu to the just stopped CPU.
+ *
+ * @cpu: The CPU state.
+ */
+static void mcd_set_stop_cpu(CPUState *cpu)
+{
+    mcdserver_state.c_cpu = cpu;
+}
+
+/**
+ * mcd_init_debug_class() - initialize mcd-specific DebugClass
+ */
+static void mcd_init_debug_class(void){
+    Object *obj;
+    obj = object_new(TYPE_DEBUG);
+    DebugState *ds = DEBUG(obj);
+    DebugClass *dc = DEBUG_GET_CLASS(ds);
+    dc->set_stop_cpu = mcd_set_stop_cpu;
+    MachineState *ms = MACHINE(qdev_get_machine());
+    ms->debug_state = ds;
+}
+
 /**
  * mcd_init_mcdserver_state() - Initializes the mcdserver_state struct.
  *
@@ -119,6 +155,35 @@ static void mcd_chr_event(void *opaque, QEMUChrEvent event)
  */
 static void mcd_init_mcdserver_state(void)
 {
+    g_assert(!mcdserver_state.init);
+    memset(&mcdserver_state, 0, sizeof(MCDState));
+    mcdserver_state.init = true;
+    mcdserver_state.str_buf = g_string_new(NULL);
+    mcdserver_state.mem_buf = g_byte_array_sized_new(MAX_PACKET_LENGTH);
+    mcdserver_state.last_packet = g_byte_array_sized_new(MAX_PACKET_LENGTH + 4);
+
+    /*
+     * What single-step modes are supported is accelerator dependent.
+     * By default try to use no IRQs and no timers while single
+     * stepping so as to make single stepping like a typical ICE HW step.
+     */
+    mcdserver_state.supported_sstep_flags =
+        accel_supported_gdbstub_sstep_flags();
+    mcdserver_state.sstep_flags = SSTEP_ENABLE | SSTEP_NOIRQ | SSTEP_NOTIMER;
+    mcdserver_state.sstep_flags &= mcdserver_state.supported_sstep_flags;
+
+    /* init query table */
+    init_query_cmds_table(mcdserver_state.mcd_query_cmds_table);
+
+    /* at this time the cpu hans't been started! -> set cpu_state */
+    mcd_cpu_state_st cpu_state =  {
+            .state = CORE_STATE_HALTED,
+            .info_str = STATE_STR_INIT_HALTED,
+    };
+    mcdserver_state.cpu_state = cpu_state;
+
+    /* create new debug object */
+    mcd_init_debug_class();
 }
 
 /**
@@ -128,6 +193,84 @@ static void mcd_init_mcdserver_state(void)
  */
 static void reset_mcdserver_state(void)
 {
+    g_free(mcdserver_state.processes);
+    mcdserver_state.processes = NULL;
+    mcdserver_state.process_num = 0;
+}
+
+/**
+ * mcd_create_default_process() - Creates a default process for debugging.
+ *
+ * This function creates a new, not yet attached, process with an ID one above
+ * the previous maximum ID.
+ * @s: A MCDState object.
+ */
+static void mcd_create_default_process(MCDState *s)
+{
+    MCDProcess *process;
+    int max_pid = 0;
+
+    if (mcdserver_state.process_num) {
+        max_pid = s->processes[s->process_num - 1].pid;
+    }
+
+    s->processes = g_renew(MCDProcess, s->processes, ++s->process_num);
+    process = &s->processes[s->process_num - 1];
+
+    /* We need an available PID slot for this process */
+    assert(max_pid < UINT32_MAX);
+
+    process->pid = max_pid + 1;
+    process->attached = false;
+}
+
+/**
+ * find_cpu_clusters() - Returns the CPU cluster of the child object.
+ *
+ * @param[in] child Object with unknown CPU cluster.
+ * @param[in] opaque Pointer to an MCDState object.
+ */
+static int find_cpu_clusters(Object *child, void *opaque)
+{
+    if (object_dynamic_cast(child, TYPE_CPU_CLUSTER)) {
+        MCDState *s = (MCDState *) opaque;
+        CPUClusterState *cluster = CPU_CLUSTER(child);
+        MCDProcess *process;
+
+        s->processes = g_renew(MCDProcess, s->processes, ++s->process_num);
+
+        process = &s->processes[s->process_num - 1];
+        assert(cluster->cluster_id != UINT32_MAX);
+        process->pid = cluster->cluster_id + 1;
+        process->attached = false;
+
+        return 0;
+    }
+
+    return object_child_foreach(child, find_cpu_clusters, opaque);
+}
+
+/**
+ * pid_order() - Compares process IDs.
+ *
+ * This function returns -1 if process "a" has a ower process ID than "b".
+ * If "b" has a lower ID than "a" 1 is returned and if they are qual 0 is
+ * returned.
+ * @a: Process a.
+ * @b: Process b.
+ */
+static int pid_order(const void *a, const void *b)
+{
+    MCDProcess *pa = (MCDProcess *) a;
+    MCDProcess *pb = (MCDProcess *) b;
+
+    if (pa->pid < pb->pid) {
+        return -1;
+    } else if (pa->pid > pb->pid) {
+        return 1;
+    } else {
+        return 0;
+    }
 }
 
 /**
@@ -141,6 +284,17 @@ static void reset_mcdserver_state(void)
  */
 static void create_processes(MCDState *s)
 {
+    object_child_foreach(object_get_root(), find_cpu_clusters, s);
+
+    if (mcdserver_state.processes) {
+        /* Sort by PID */
+        qsort(mcdserver_state.processes,
+              mcdserver_state.process_num,
+              sizeof(mcdserver_state.processes[0]),
+              pid_order);
+    }
+
+    mcd_create_default_process(s);
 }
 
 int mcdserver_start(const char *device)
-- 
2.34.1