qemu/pc-bios/s390-ccw/main.c
Eugene (jno) Dvurechenski b39b7718dc pc-bios/s390-ccw: Pass selected SCSI device to IPL
There is ,bootindex=%d argument to specify the lookup order of
boot devices.

If a bootindex assigned to the device, then IPL Parameter Info Block
is created for that device when it is IPLed from.

If it is a mere SCSI device (not FCP), then IPIB is created with a
special SCSI type and its fields are used to store SCSI address of the
device. This new ipl block is private to qemu for now.

If the device to IPL from is specified this way, then SCSI bus lookup
is bypassed and prescribed devices uses the address specified.

Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com>
Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-07-11 09:48:05 +02:00

129 lines
3.2 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"
#include "virtio.h"
char stack[PAGE_SIZE * 8] __attribute__((__aligned__(PAGE_SIZE)));
static SubChannelId blk_schid = { .one = 1 };
IplParameterBlock iplb __attribute__((__aligned__(PAGE_SIZE)));
/*
* 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)
{
SubChannelId *schid = (SubChannelId *) 184;
uint32_t *zeroes = (uint32_t *) 188;
*schid = blk_schid;
*zeroes = 0;
}
void panic(const char *string)
{
sclp_print(string);
disabled_wait();
while (1) { }
}
static bool find_dev(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_supported(blk_schid)) {
continue;
}
if ((dev_no < 0) || (schib->pmcw.dev == dev_no)) {
return true;
}
}
return false;
}
static void virtio_setup(void)
{
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 (store_iplb(&iplb)) {
switch (iplb.pbt) {
case S390_IPL_TYPE_CCW:
dev_no = iplb.ccw.devno;
debug_print_int("device no. ", dev_no);
blk_schid.ssid = iplb.ccw.ssid & 0x3;
debug_print_int("ssid ", blk_schid.ssid);
found = find_dev(&schib, dev_no);
break;
case S390_IPL_TYPE_QEMU_SCSI:
{
VDev *vdev = virtio_get_device();
vdev->scsi_device_selected = true;
vdev->selected_scsi_device.channel = iplb.scsi.channel;
vdev->selected_scsi_device.target = iplb.scsi.target;
vdev->selected_scsi_device.lun = iplb.scsi.lun;
blk_schid.ssid = iplb.scsi.ssid & 0x3;
found = find_dev(&schib, iplb.scsi.devno);
break;
}
default:
panic("List-directed IPL not supported yet!\n");
}
} else {
for (ssid = 0; ssid < 0x3; ssid++) {
blk_schid.ssid = ssid;
found = find_dev(&schib, -1);
if (found) {
break;
}
}
}
IPL_assert(found, "No virtio device found");
virtio_setup_device(blk_schid);
IPL_assert(virtio_ipl_disk_is_valid(), "No valid IPL device detected");
}
int main(void)
{
sclp_setup();
virtio_setup();
zipl_load(); /* no return */
panic("Failed to load OS from hard disk\n");
return 0; /* make compiler happy */
}