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11#include "s390-ccw.h"
12#include "virtio.h"
13
14char stack[PAGE_SIZE * 8] __attribute__((__aligned__(PAGE_SIZE)));
15uint64_t boot_value;
16static SubChannelId blk_schid = { .one = 1 };
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22
23void write_subsystem_identification(void)
24{
25 SubChannelId *schid = (SubChannelId *) 184;
26 uint32_t *zeroes = (uint32_t *) 188;
27
28 *schid = blk_schid;
29 *zeroes = 0;
30}
31
32
33void panic(const char *string)
34{
35 sclp_print(string);
36 disabled_wait();
37 while (1) { }
38}
39
40static bool find_dev(Schib *schib, int dev_no)
41{
42 int i, r;
43
44 for (i = 0; i < 0x10000; i++) {
45 blk_schid.sch_no = i;
46 r = stsch_err(blk_schid, schib);
47 if ((r == 3) || (r == -EIO)) {
48 break;
49 }
50 if (!schib->pmcw.dnv) {
51 continue;
52 }
53 if (!virtio_is_supported(blk_schid)) {
54 continue;
55 }
56 if ((dev_no < 0) || (schib->pmcw.dev == dev_no)) {
57 return true;
58 }
59 }
60
61 return false;
62}
63
64static void virtio_setup(uint64_t dev_info)
65{
66 Schib schib;
67 int ssid;
68 bool found = false;
69 uint16_t dev_no;
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76 enable_mss_facility();
77
78 if (dev_info != -1) {
79 dev_no = dev_info & 0xffff;
80 debug_print_int("device no. ", dev_no);
81 blk_schid.ssid = (dev_info >> 16) & 0x3;
82 debug_print_int("ssid ", blk_schid.ssid);
83 found = find_dev(&schib, dev_no);
84 } else {
85 for (ssid = 0; ssid < 0x3; ssid++) {
86 blk_schid.ssid = ssid;
87 found = find_dev(&schib, -1);
88 if (found) {
89 break;
90 }
91 }
92 }
93
94 IPL_assert(found, "No virtio device found");
95
96 virtio_setup_device(blk_schid);
97
98 IPL_assert(virtio_ipl_disk_is_valid(), "No valid IPL device detected");
99}
100
101int main(void)
102{
103 sclp_setup();
104 debug_print_int("boot reg[7] ", boot_value);
105 virtio_setup(boot_value);
106
107 zipl_load();
108
109 panic("Failed to load OS from hard disk\n");
110 return 0;
111}
112