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 "sysemu/sysemu.h"
  18 #include "hw/s390x/sclp.h"
  19 #include "qemu/module.h"
  20 #include "hw/s390x/event-facility.h"
  21 #include "cpu.h"
  22 #include "sysemu/cpus.h"
  23
  24 typedef struct ConfigMgtData {
  25     EventBufferHeader ebh;
  26     uint8_t reserved;
  27     uint8_t event_qualifier;
  28 } QEMU_PACKED ConfigMgtData;
  29
  30 #define EVENT_QUAL_CPU_CHANGE  1
  31
  32 void raise_irq_cpu_hotplug(void)
  33 {
  34     Object *obj = object_resolve_path_type("", TYPE_SCLP_CPU_HOTPLUG, NULL);
  35
  36     SCLP_EVENT(obj)->event_pending = true;
  37
  38     /* Trigger SCLP read operation */
  39     sclp_service_interrupt(0);
  40 }
  41
  42 static sccb_mask_t send_mask(void)
  43 {
  44     return SCLP_EVENT_MASK_CONFIG_MGT_DATA;
  45 }
  46
  47 static sccb_mask_t receive_mask(void)
  48 {
  49     return 0;
  50 }
  51
  52 static int read_event_data(SCLPEvent *event, EventBufferHeader *evt_buf_hdr,
  53                            int *slen)
  54 {
  55     ConfigMgtData *cdata = (ConfigMgtData *) evt_buf_hdr;
  56     if (*slen < sizeof(ConfigMgtData)) {
  57         return 0;
  58     }
  59
  60     /* Event is no longer pending */
  61     if (!event->event_pending) {
  62         return 0;
  63     }
  64     event->event_pending = false;
  65
  66     /* Event header data */
  67     cdata->ebh.length = cpu_to_be16(sizeof(ConfigMgtData));
  68     cdata->ebh.type = SCLP_EVENT_CONFIG_MGT_DATA;
  69     cdata->ebh.flags |= SCLP_EVENT_BUFFER_ACCEPTED;
  70
  71     /* Trigger a rescan of CPUs by setting event qualifier */
  72     cdata->event_qualifier = EVENT_QUAL_CPU_CHANGE;
  73     *slen -= sizeof(ConfigMgtData);
  74
  75     return 1;
  76 }
  77
  78 static void cpu_class_init(ObjectClass *oc, void *data)
  79 {
  80     SCLPEventClass *k = SCLP_EVENT_CLASS(oc);
  81     DeviceClass *dc = DEVICE_CLASS(oc);
  82
  83     k->get_send_mask = send_mask;
  84     k->get_receive_mask = receive_mask;
  85     k->read_event_data = read_event_data;
  86     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
  87     /*
  88      * Reason: raise_irq_cpu_hotplug() depends on an unique
  89      * TYPE_SCLP_CPU_HOTPLUG device, which is already created
  90      * by the sclp event facility
  91      */
  92     dc->user_creatable = false;
  93 }
  94
  95 static const TypeInfo sclp_cpu_info = {
  96     .name          = TYPE_SCLP_CPU_HOTPLUG,
  97     .parent        = TYPE_SCLP_EVENT,
  98     .instance_size = sizeof(SCLPEvent),
  99     .class_init    = cpu_class_init,
 100     .class_size    = sizeof(SCLPEventClass),
 101 };
 102
 103 static void sclp_cpu_register_types(void)
 104 {
 105     type_register_static(&sclp_cpu_info);
 106 }
 107
 108 type_init(sclp_cpu_register_types)