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