xref: /openbmc/qemu/pc-bios/s390-ccw/main.c (revision 01c22f2c)
1 /*
2  * S390 virtio-ccw loading program
3  *
4  * Copyright (c) 2013 Alexander Graf <agraf@suse.de>
5  *
6  * This work is licensed under the terms of the GNU GPL, version 2 or (at
7  * your option) any later version. See the COPYING file in the top-level
8  * directory.
9  */
10 
11 #include "s390-ccw.h"
12 
13 char stack[PAGE_SIZE * 8] __attribute__((__aligned__(PAGE_SIZE)));
14 uint64_t boot_value;
15 
16 void virtio_panic(const char *string)
17 {
18     sclp_print(string);
19     disabled_wait();
20     while (1) { }
21 }
22 
23 static void virtio_setup(uint64_t dev_info)
24 {
25     struct subchannel_id blk_schid = { .one = 1 };
26     struct schib schib;
27     int i;
28     int r;
29     bool found = false;
30     bool check_devno = false;
31     uint16_t dev_no = -1;
32 
33     if (dev_info != -1) {
34         check_devno = true;
35         dev_no = dev_info & 0xffff;
36         debug_print_int("device no. ", dev_no);
37         blk_schid.ssid = (dev_info >> 16) & 0x3;
38         if (blk_schid.ssid != 0) {
39             debug_print_int("ssid ", blk_schid.ssid);
40             if (enable_mss_facility() != 0) {
41                 virtio_panic("Failed to enable mss facility\n");
42             }
43         }
44     }
45 
46     for (i = 0; i < 0x10000; i++) {
47         blk_schid.sch_no = i;
48         r = stsch_err(blk_schid, &schib);
49         if (r == 3) {
50             break;
51         }
52         if (schib.pmcw.dnv) {
53             if (!check_devno || (schib.pmcw.dev == dev_no)) {
54                 if (virtio_is_blk(blk_schid)) {
55                     found = true;
56                     break;
57                 }
58             }
59         }
60     }
61 
62     if (!found) {
63         virtio_panic("No virtio-blk device found!\n");
64     }
65 
66     virtio_setup_block(blk_schid);
67 }
68 
69 int main(void)
70 {
71     sclp_setup();
72     debug_print_int("boot reg[7] ", boot_value);
73     virtio_setup(boot_value);
74 
75     if (zipl_load() < 0)
76         sclp_print("Failed to load OS from hard disk\n");
77     disabled_wait();
78     while (1) { }
79 }
80