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
  16 #include "qemu/osdep.h"
  17 #include "hw/s390x/sclp.h"
  18 #include "qemu/module.h"
  19 #include "hw/s390x/event-facility.h"
  20 #include "sysemu/cpus.h"
  21
  22 typedef struct ConfigMgtData {
  23     EventBufferHeader ebh;
  24     uint8_t reserved;
  25     uint8_t event_qualifier;
  26 } QEMU_PACKED ConfigMgtData;
  27
  28 #define EVENT_QUAL_CPU_CHANGE  1
  29
  30 void raise_irq_cpu_hotplug(void)
  31 {
  32     Object *obj = object_resolve_path_type("", TYPE_SCLP_CPU_HOTPLUG, NULL);
  33
  34     SCLP_EVENT(obj)->event_pending = true;
  35
  36     /* Trigger SCLP read operation */
  37     sclp_service_interrupt(0);
  38 }
  39
  40 static sccb_mask_t send_mask(void)
  41 {
  42     return SCLP_EVENT_MASK_CONFIG_MGT_DATA;
  43 }
  44
  45 static sccb_mask_t receive_mask(void)
  46 {
  47     return 0;
  48 }
  49
  50 static int read_event_data(SCLPEvent *event, EventBufferHeader *evt_buf_hdr,
  51                            int *slen)
  52 {
  53     ConfigMgtData *cdata = (ConfigMgtData *) evt_buf_hdr;
  54     if (*slen < sizeof(ConfigMgtData)) {
  55         return 0;
  56     }
  57
  58     /* Event is no longer pending */
  59     if (!event->event_pending) {
  60         return 0;
  61     }
  62     event->event_pending = false;
  63
  64     /* Event header data */
  65     cdata->ebh.length = cpu_to_be16(sizeof(ConfigMgtData));
  66     cdata->ebh.type = SCLP_EVENT_CONFIG_MGT_DATA;
  67     cdata->ebh.flags |= SCLP_EVENT_BUFFER_ACCEPTED;
  68
  69     /* Trigger a rescan of CPUs by setting event qualifier */
  70     cdata->event_qualifier = EVENT_QUAL_CPU_CHANGE;
  71     *slen -= sizeof(ConfigMgtData);
  72
  73     return 1;
  74 }
  75
  76 static void cpu_class_init(ObjectClass *oc, void *data)
  77 {
  78     SCLPEventClass *k = SCLP_EVENT_CLASS(oc);
  79     DeviceClass *dc = DEVICE_CLASS(oc);
  80
  81     k->get_send_mask = send_mask;
  82     k->get_receive_mask = receive_mask;
  83     k->read_event_data = read_event_data;
  84     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
  85     /*
  86      * Reason: raise_irq_cpu_hotplug() depends on an unique
  87      * TYPE_SCLP_CPU_HOTPLUG device, which is already created
  88      * by the sclp event facility
  89      */
  90     dc->user_creatable = false;
  91 }
  92
  93 static const TypeInfo sclp_cpu_info = {
  94     .name          = TYPE_SCLP_CPU_HOTPLUG,
  95     .parent        = TYPE_SCLP_EVENT,
  96     .instance_size = sizeof(SCLPEvent),
  97     .class_init    = cpu_class_init,
  98     .class_size    = sizeof(SCLPEventClass),
  99 };
 100
 101 static void sclp_cpu_register_types(void)
 102 {
 103     type_register_static(&sclp_cpu_info);
 104 }
 105
 106 type_init(sclp_cpu_register_types)