hw/s390x/sclp.c

   1 /*
   2  * SCLP Support
   3  *
   4  * Copyright IBM, Corp. 2012
   5  *
   6  * Authors:
   7  *  Christian Borntraeger <borntraeger@de.ibm.com>
   8  *  Heinz Graalfs <graalfs@linux.vnet.ibm.com>
   9  *
  10  * This work is licensed under the terms of the GNU GPL, version 2 or (at your
  11  * option) any later version.  See the COPYING file in the top-level directory.
  12  *
  13  */
  14
  15 #include "cpu.h"
  16 #include "kvm.h"
  17 #include "memory.h"
  18
  19 #include "sclp.h"
  20
  21 /* Provide information about the configuration, CPUs and storage */
  22 static void read_SCP_info(SCCB *sccb)
  23 {
  24     ReadInfo *read_info = (ReadInfo *) sccb;
  25     int shift = 0;
  26
  27     while ((ram_size >> (20 + shift)) > 65535) {
  28         shift++;
  29     }
  30     read_info->rnmax = cpu_to_be16(ram_size >> (20 + shift));
  31     read_info->rnsize = 1 << shift;
  32     sccb->h.response_code = cpu_to_be16(SCLP_RC_NORMAL_READ_COMPLETION);
  33 }
  34
  35 static void sclp_execute(SCCB *sccb, uint64_t code)
  36 {
  37     switch (code) {
  38     case SCLP_CMDW_READ_SCP_INFO:
  39     case SCLP_CMDW_READ_SCP_INFO_FORCED:
  40         read_SCP_info(sccb);
  41         break;
  42     default:
  43         sccb->h.response_code = cpu_to_be16(SCLP_RC_INVALID_SCLP_COMMAND);
  44         break;
  45     }
  46 }
  47
  48 int sclp_service_call(uint32_t sccb, uint64_t code)
  49 {
  50     int r = 0;
  51     SCCB work_sccb;
  52
  53     hwaddr sccb_len = sizeof(SCCB);
  54
  55     /* first some basic checks on program checks */
  56     if (cpu_physical_memory_is_io(sccb)) {
  57         r = -PGM_ADDRESSING;
  58         goto out;
  59     }
  60     if (sccb & ~0x7ffffff8ul) {
  61         r = -PGM_SPECIFICATION;
  62         goto out;
  63     }
  64
  65     /*
  66      * we want to work on a private copy of the sccb, to prevent guests
  67      * from playing dirty tricks by modifying the memory content after
  68      * the host has checked the values
  69      */
  70     cpu_physical_memory_read(sccb, &work_sccb, sccb_len);
  71
  72     /* Valid sccb sizes */
  73     if (be16_to_cpu(work_sccb.h.length) < sizeof(SCCBHeader) ||
  74         be16_to_cpu(work_sccb.h.length) > SCCB_SIZE) {
  75         r = -PGM_SPECIFICATION;
  76         goto out;
  77     }
  78
  79     sclp_execute((SCCB *)&work_sccb, code);
  80
  81     cpu_physical_memory_write(sccb, &work_sccb,
  82                               be16_to_cpu(work_sccb.h.length));
  83
  84     sclp_service_interrupt(sccb);
  85
  86 out:
  87     return r;
  88 }
  89
  90 void sclp_service_interrupt(uint32_t sccb)
  91 {
  92     s390_sclp_extint(sccb & ~3);
  93 }
  94
  95 /* qemu object creation and initialization functions */
  96
  97 static void s390_sclp_device_class_init(ObjectClass *klass, void *data)
  98 {
  99     SysBusDeviceClass *dc = SYS_BUS_DEVICE_CLASS(klass);
 100
 101     dc->init = s390_sclp_dev_init;
 102 }
 103
 104 static TypeInfo s390_sclp_device_info = {
 105     .name = TYPE_DEVICE_S390_SCLP,
 106     .parent = TYPE_SYS_BUS_DEVICE,
 107     .instance_size = sizeof(S390SCLPDevice),
 108     .class_init = s390_sclp_device_class_init,
 109     .class_size = sizeof(S390SCLPDeviceClass),
 110     .abstract = true,
 111 };
 112
 113 static void s390_sclp_register_types(void)
 114 {
 115     type_register_static(&s390_sclp_device_info);
 116 }
 117
 118 type_init(s390_sclp_register_types)