hw/s390x/sclpcpu.c

   1 /*
   2  * SCLP event type
   3  *    Signal CPU - Trigger SCLP interrupt for system CPU configure or
   4  *    de-configure
   5  *
   6  * Copyright IBM, Corp. 2013
   7  *
   8  * Authors:
   9  *  Thang Pham <thang.pham@us.ibm.com>
  10  *
  11  * This work is licensed under the terms of the GNU GPL, version 2 or (at your
  12  * option) any later version.  See the COPYING file in the top-level directory.
  13  *
  14  */
  15 #include "sysemu/sysemu.h"
  16 #include "hw/s390x/sclp.h"
  17 #include "hw/s390x/event-facility.h"
  18 #include "cpu.h"
  19 #include "sysemu/cpus.h"
  20 #include "sysemu/kvm.h"
  21
  22 typedef struct ConfigMgtData {
  23     EventBufferHeader ebh;
  24     uint8_t reserved;
  25     uint8_t event_qualifier;
  26 } QEMU_PACKED ConfigMgtData;
  27
  28 static qemu_irq *irq_cpu_hotplug; /* Only used in this file */
  29
  30 #define EVENT_QUAL_CPU_CHANGE  1
  31
  32 void raise_irq_cpu_hotplug(void)
  33 {
  34     qemu_irq_raise(*irq_cpu_hotplug);
  35 }
  36
  37 static unsigned int send_mask(void)
  38 {
  39     return SCLP_EVENT_MASK_CONFIG_MGT_DATA;
  40 }
  41
  42 static unsigned int receive_mask(void)
  43 {
  44     return 0;
  45 }
  46
  47 static int read_event_data(SCLPEvent *event, EventBufferHeader *evt_buf_hdr,
  48                            int *slen)
  49 {
  50     ConfigMgtData *cdata = (ConfigMgtData *) evt_buf_hdr;
  51     if (*slen < sizeof(ConfigMgtData)) {
  52         return 0;
  53     }
  54
  55     /* Event is no longer pending */
  56     if (!event->event_pending) {
  57         return 0;
  58     }
  59     event->event_pending = false;
  60
  61     /* Event header data */
  62     cdata->ebh.length = cpu_to_be16(sizeof(ConfigMgtData));
  63     cdata->ebh.type = SCLP_EVENT_CONFIG_MGT_DATA;
  64     cdata->ebh.flags |= SCLP_EVENT_BUFFER_ACCEPTED;
  65
  66     /* Trigger a rescan of CPUs by setting event qualifier */
  67     cdata->event_qualifier = EVENT_QUAL_CPU_CHANGE;
  68     *slen -= sizeof(ConfigMgtData);
  69
  70     return 1;
  71 }
  72
  73 static void trigger_signal(void *opaque, int n, int level)
  74 {
  75     SCLPEvent *event = opaque;
  76     event->event_pending = true;
  77
  78     /* Trigger SCLP read operation */
  79     sclp_service_interrupt(0);
  80 }
  81
  82 static int irq_cpu_hotplug_init(SCLPEvent *event)
  83 {
  84     irq_cpu_hotplug = qemu_allocate_irqs(trigger_signal, event, 1);
  85     return 0;
  86 }
  87
  88 static void cpu_class_init(ObjectClass *oc, void *data)
  89 {
  90     SCLPEventClass *k = SCLP_EVENT_CLASS(oc);
  91
  92     k->init = irq_cpu_hotplug_init;
  93     k->get_send_mask = send_mask;
  94     k->get_receive_mask = receive_mask;
  95     k->read_event_data = read_event_data;
  96     k->write_event_data = NULL;
  97 }
  98
  99 static const TypeInfo sclp_cpu_info = {
 100     .name          = "sclp-cpu-hotplug",
 101     .parent        = TYPE_SCLP_EVENT,
 102     .instance_size = sizeof(SCLPEvent),
 103     .class_init    = cpu_class_init,
 104     .class_size    = sizeof(SCLPEventClass),
 105 };
 106
 107 static void sclp_cpu_register_types(void)
 108 {
 109     type_register_static(&sclp_cpu_info);
 110 }
 111
 112 type_init(sclp_cpu_register_types)