blob: d5fe4cea1d61c5f2db606341158502f728e4218d (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
|
/*
* S390 virtio-ccw loading program
*
* Copyright (c) 2013 Alexander Graf <agraf@suse.de>
*
* This work is licensed under the terms of the GNU GPL, version 2 or (at
* your option) any later version. See the COPYING file in the top-level
* directory.
*/
#include "s390-ccw.h"
#include "virtio.h"
char stack[PAGE_SIZE * 8] __attribute__((__aligned__(PAGE_SIZE)));
char ring_area[PAGE_SIZE * 8] __attribute__((__aligned__(PAGE_SIZE)));
uint64_t boot_value;
static struct subchannel_id blk_schid = { .one = 1 };
/*
* Priniciples of Operations (SA22-7832-09) chapter 17 requires that
* a subsystem-identification is at 184-187 and bytes 188-191 are zero
* after list-directed-IPL and ccw-IPL.
*/
void write_subsystem_identification(void)
{
struct subchannel_id *schid = (struct subchannel_id *) 184;
uint32_t *zeroes = (uint32_t *) 188;
*schid = blk_schid;
*zeroes = 0;
}
void virtio_panic(const char *string)
{
sclp_print(string);
disabled_wait();
while (1) { }
}
static bool find_dev(struct schib *schib, int dev_no)
{
int i, r;
for (i = 0; i < 0x10000; i++) {
blk_schid.sch_no = i;
r = stsch_err(blk_schid, schib);
if ((r == 3) || (r == -EIO)) {
break;
}
if (!schib->pmcw.dnv) {
continue;
}
if (!virtio_is_blk(blk_schid)) {
continue;
}
if ((dev_no < 0) || (schib->pmcw.dev == dev_no)) {
return true;
}
}
return false;
}
static void virtio_setup(uint64_t dev_info)
{
struct schib schib;
int ssid;
bool found = false;
uint16_t dev_no;
/*
* We unconditionally enable mss support. In every sane configuration,
* this will succeed; and even if it doesn't, stsch_err() can deal
* with the consequences.
*/
enable_mss_facility();
if (dev_info != -1) {
dev_no = dev_info & 0xffff;
debug_print_int("device no. ", dev_no);
blk_schid.ssid = (dev_info >> 16) & 0x3;
debug_print_int("ssid ", blk_schid.ssid);
found = find_dev(&schib, dev_no);
} else {
for (ssid = 0; ssid < 0x3; ssid++) {
blk_schid.ssid = ssid;
found = find_dev(&schib, -1);
if (found) {
break;
}
}
}
if (!found) {
virtio_panic("No virtio-blk device found!\n");
}
virtio_setup_block(blk_schid);
if (!virtio_ipl_disk_is_valid()) {
virtio_panic("No valid hard disk detected.\n");
}
}
int main(void)
{
sclp_setup();
debug_print_int("boot reg[7] ", boot_value);
virtio_setup(boot_value);
zipl_load(); /* no return */
virtio_panic("Failed to load OS from hard disk\n");
return 0; /* make compiler happy */
}
|