xref: /openbmc/qemu/hw/s390x/s390-virtio-ccw.c (revision 2c9b15ca)
1 /*
2  * virtio ccw machine
3  *
4  * Copyright 2012 IBM Corp.
5  * Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
6  *
7  * This work is licensed under the terms of the GNU GPL, version 2 or (at
8  * your option) any later version. See the COPYING file in the top-level
9  * directory.
10  */
11 
12 #include "hw/boards.h"
13 #include "exec/address-spaces.h"
14 #include "s390-virtio.h"
15 #include "hw/s390x/sclp.h"
16 #include "ioinst.h"
17 #include "css.h"
18 #include "virtio-ccw.h"
19 
20 static int virtio_ccw_hcall_notify(const uint64_t *args)
21 {
22     uint64_t subch_id = args[0];
23     uint64_t queue = args[1];
24     SubchDev *sch;
25     int cssid, ssid, schid, m;
26 
27     if (ioinst_disassemble_sch_ident(subch_id, &m, &cssid, &ssid, &schid)) {
28         return -EINVAL;
29     }
30     sch = css_find_subch(m, cssid, ssid, schid);
31     if (!sch || !css_subch_visible(sch)) {
32         return -EINVAL;
33     }
34     if (queue >= VIRTIO_PCI_QUEUE_MAX) {
35         return -EINVAL;
36     }
37     virtio_queue_notify(virtio_ccw_get_vdev(sch), queue);
38     return 0;
39 
40 }
41 
42 static int virtio_ccw_hcall_early_printk(const uint64_t *args)
43 {
44     uint64_t mem = args[0];
45 
46     if (mem < ram_size) {
47         /* Early printk */
48         return 0;
49     }
50     return -EINVAL;
51 }
52 
53 static void virtio_ccw_register_hcalls(void)
54 {
55     s390_register_virtio_hypercall(KVM_S390_VIRTIO_CCW_NOTIFY,
56                                    virtio_ccw_hcall_notify);
57     /* Tolerate early printk. */
58     s390_register_virtio_hypercall(KVM_S390_VIRTIO_NOTIFY,
59                                    virtio_ccw_hcall_early_printk);
60 }
61 
62 static void ccw_init(QEMUMachineInitArgs *args)
63 {
64     ram_addr_t my_ram_size = args->ram_size;
65     MemoryRegion *sysmem = get_system_memory();
66     MemoryRegion *ram = g_new(MemoryRegion, 1);
67     int shift = 0;
68     uint8_t *storage_keys;
69     int ret;
70     VirtualCssBus *css_bus;
71 
72     /* s390x ram size detection needs a 16bit multiplier + an increment. So
73        guests > 64GB can be specified in 2MB steps etc. */
74     while ((my_ram_size >> (20 + shift)) > 65535) {
75         shift++;
76     }
77     my_ram_size = my_ram_size >> (20 + shift) << (20 + shift);
78 
79     /* let's propagate the changed ram size into the global variable. */
80     ram_size = my_ram_size;
81 
82     /* get a BUS */
83     css_bus = virtual_css_bus_init();
84     s390_sclp_init();
85     s390_init_ipl_dev(args->kernel_filename, args->kernel_cmdline,
86                       args->initrd_filename, "s390-ccw.img");
87 
88     /* register hypercalls */
89     virtio_ccw_register_hcalls();
90 
91     /* allocate RAM */
92     memory_region_init_ram(ram, NULL, "s390.ram", my_ram_size);
93     vmstate_register_ram_global(ram);
94     memory_region_add_subregion(sysmem, 0, ram);
95 
96     /* allocate storage keys */
97     storage_keys = g_malloc0(my_ram_size / TARGET_PAGE_SIZE);
98 
99     /* init CPUs */
100     s390_init_cpus(args->cpu_model, storage_keys);
101 
102     if (kvm_enabled()) {
103         kvm_s390_enable_css_support(s390_cpu_addr2state(0));
104     }
105     /*
106      * Create virtual css and set it as default so that non mcss-e
107      * enabled guests only see virtio devices.
108      */
109     ret = css_create_css_image(VIRTUAL_CSSID, true);
110     assert(ret == 0);
111 
112     /* Create VirtIO network adapters */
113     s390_create_virtio_net(BUS(css_bus), "virtio-net-ccw");
114 }
115 
116 static QEMUMachine ccw_machine = {
117     .name = "s390-ccw-virtio",
118     .alias = "s390-ccw",
119     .desc = "VirtIO-ccw based S390 machine",
120     .init = ccw_init,
121     .block_default_type = IF_VIRTIO,
122     .no_cdrom = 1,
123     .no_floppy = 1,
124     .no_serial = 1,
125     .no_parallel = 1,
126     .no_sdcard = 1,
127     .use_sclp = 1,
128     .max_cpus = 255,
129     DEFAULT_MACHINE_OPTIONS,
130 };
131 
132 static void ccw_machine_init(void)
133 {
134     qemu_register_machine(&ccw_machine);
135 }
136 
137 machine_init(ccw_machine_init)
138