xemu/pc-bios/s390-ccw/main.c
Cornelia Huck 22d67ab55a s390-ccw.img: Detect devices with stsch.
stsch is the canonical way to detect devices. As a bonus, we can
abort the loop if we get cc 3, and we need to check only the valid
devices (dnv set).

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-04-26 20:18:24 +02:00

62 lines
1.2 KiB
C

/*
* 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"
struct subchannel_id blk_schid;
char stack[PAGE_SIZE * 8] __attribute__((__aligned__(PAGE_SIZE)));
void virtio_panic(const char *string)
{
sclp_print(string);
disabled_wait();
while (1) { }
}
static void virtio_setup(void)
{
struct schib schib;
int i;
int r;
bool found = false;
blk_schid.one = 1;
for (i = 0; i < 0x10000; i++) {
blk_schid.sch_no = i;
r = stsch_err(blk_schid, &schib);
if (r == 3) {
break;
}
if (schib.pmcw.dnv) {
if (virtio_is_blk(blk_schid)) {
found = true;
break;
}
}
}
if (!found) {
virtio_panic("No virtio-blk device found!\n");
}
virtio_setup_block(blk_schid);
}
int main(void)
{
sclp_setup();
virtio_setup();
if (zipl_load() < 0)
sclp_print("Failed to load OS from hard disk\n");
disabled_wait();
while (1) { }
}