The s390-ccw bios creates the the virtqueue at 100MB. For
big ramdisks or offsets (via zipl) this gets overwritten.
As a quick band-aid, lets move the virtqueue into the bss
section, which is at 0x7f00000. As the bios code (text) is
at 0x7e00000 we can now handle ramdisk which are ~27MB
bigger.
Long term we want to make the s390-ccw bios position
independent and load of at the end of memory.
Reported-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Message-Id: <1425310029-53396-2-git-send-email-borntraeger@de.ibm.com>
Fix some sparse warnings in the s390-ccw bios.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
POP chapter 17 requires to store a subsystem information word at 184
during IPL. Furthermore bytes 188-191 should be zero. The bootmap might
contain data blocks that are written to the first page. We have to
write these values after we processed the bootmap and before the final
IPL.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
We have to set the cssid to 0, otherwise the stsch code will
return an operand exception without the m bit. In the same way
we should set m=0.
This case was triggered in some cases during reboot, if for some
reason the location of blk_schid.cssid contains 1 and m was 0.
Turns out that the qemu elf loader does not zero out the bss section
on reboot.
The symptom was an dump of the old kernel with several areas
overwritten. The bootloader does not register a program check
handler, so bios exception jumped back into the old kernel.
Lets just use a local struct with a designed initializer. That
will guarantee that all other subelements are initialized to 0.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
We now take the subchannel set id also into account to find the boot device.
If we want to use a subchannel set other than the default set 0, we first
need to enable the mss facility.
Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Use the passed device, if there is no device, use the first applicable device.
Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
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>
dont waste cpu power on an error condition. Lets stop the guest
with a disabled wait.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
This C file is the main driving piece of the s390 ccw firmware. It
provides a search for a workable block device, sets it as the default
to boot off of and boots from it.
Signed-off-by: Alexander Graf <agraf@suse.de>
Christian Borntraeger