s390: Add CPU reset handler

Add a CPU reset handler to have all CPUs in a PoP compliant
state.

Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
[agraf: move hw/hw.h into existing ifdef]
Signed-off-by: Alexander Graf <agraf@suse.de>

target-s390x/cpu.c

@@ -4,6 +4,7 @@
  * Copyright (c) 2009 Ulrich Hecht
  * Copyright (c) 2011 Alexander Graf
  * Copyright (c) 2012 SUSE LINUX Products GmbH
+ * Copyright (c) 2012 IBM Corp.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -18,15 +19,21 @@
  * You should have received a copy of the GNU Lesser General Public
  * License along with this library; if not, see
  * <http://www.gnu.org/licenses/lgpl-2.1.html>
+ * Contributions after 2012-12-11 are licensed under the terms of the
+ * GNU GPL, version 2 or (at your option) any later version.
  */
 
 #include "cpu.h"
 #include "qemu-common.h"
 #include "qemu/timer.h"
 #ifndef CONFIG_USER_ONLY
+#include "hw/hw.h"
 #include "sysemu/arch_init.h"
 #endif
 
+#define CR0_RESET       0xE0UL
+#define CR14_RESET      0xC2000000UL;
+
 /* generate CPU information for cpu -? */
 void s390_cpu_list(FILE *f, fprintf_function cpu_fprintf)
 {
@@ -63,14 +70,33 @@ static void s390_cpu_reset(CPUState *s)
         log_cpu_state(env, 0);
     }
 
+    s390_del_running_cpu(env);
+
     scc->parent_reset(s);
 
     memset(env, 0, offsetof(CPUS390XState, breakpoints));
-    /* FIXME: reset vector? */
+
+    /* architectured initial values for CR 0 and 14 */
+    env->cregs[0] = CR0_RESET;
+    env->cregs[14] = CR14_RESET;
+    /* set halted to 1 to make sure we can add the cpu in
+     * s390_ipl_cpu code, where env->halted is set back to 0
+     * after incrementing the cpu counter */
+#if !defined(CONFIG_USER_ONLY)
+    env->halted = 1;
+#endif
     tlb_flush(env, 1);
-    s390_add_running_cpu(env);
 }
 
+#if !defined(CONFIG_USER_ONLY)
+static void s390_cpu_machine_reset_cb(void *opaque)
+{
+    S390CPU *cpu = opaque;
+
+    cpu_reset(CPU(cpu));
+}
+#endif
+
 static void s390_cpu_initfn(Object *obj)
 {
     S390CPU *cpu = S390_CPU(obj);
@@ -82,12 +108,17 @@ static void s390_cpu_initfn(Object *obj)
 
     cpu_exec_init(env);
 #if !defined(CONFIG_USER_ONLY)
+    qemu_register_reset(s390_cpu_machine_reset_cb, cpu);
     qemu_get_timedate(&tm, 0);
     env->tod_offset = TOD_UNIX_EPOCH +
                       (time2tod(mktimegm(&tm)) * 1000000000ULL);
     env->tod_basetime = 0;
     env->tod_timer = qemu_new_timer_ns(vm_clock, s390x_tod_timer, cpu);
     env->cpu_timer = qemu_new_timer_ns(vm_clock, s390x_cpu_timer, cpu);
+    /* set env->halted state to 1 to avoid decrementing the running
+     * cpu counter in s390_cpu_reset to a negative number at
+     * initial ipl */
+    env->halted = 1;
 #endif
     env->cpu_num = cpu_num++;
     env->ext_index = -1;

target-s390x/kvm.c

@@ -89,7 +89,14 @@ int kvm_arch_init_vcpu(CPUState *cpu)
 
 void kvm_arch_reset_vcpu(CPUState *cpu)
 {
-    /* FIXME: add code to reset vcpu. */
+   /* The initial reset call is needed here to reset in-kernel
+    * vcpu data that we can't access directly from QEMU
+    * (i.e. with older kernels which don't support sync_regs/ONE_REG).
+    * Before this ioctl cpu_synchronize_state() is called in common kvm
+    * code (kvm-all) */
+    if (kvm_vcpu_ioctl(cpu, KVM_S390_INITIAL_RESET, NULL)) {
+        perror("Can't reset vcpu\n");
+    }
 }
 
 int kvm_arch_put_registers(CPUState *cs, int level)