On 2020-05-27 10:55, Cornelia Huck wrote:
On Mon, 18 May 2020 18:07:27 +0200
Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote:
First step for testing the channel subsystem is to enumerate the css and
retrieve the css devices.
This tests the success of STSCH I/O instruction, we do not test the
reaction of the VM for an instruction with wrong parameters.
Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
---
s390x/Makefile | 1 +
s390x/css.c | 89 +++++++++++++++++++++++++++++++++++++++++++++
s390x/unittests.cfg | 4 ++
3 files changed, 94 insertions(+)
create mode 100644 s390x/css.c
(...)
+static void test_enumerate(void)
+{
+ struct pmcw *pmcw = &schib.pmcw;
+ int cc;
+ int scn;
+ int scn_found = 0;
+ int dev_found = 0;
+
+ for (scn = 0; scn < 0xffff; scn++) {
+ cc = stsch(scn|SID_ONE, &schib);
+ switch (cc) {
+ case 0: /* 0 means SCHIB stored */
+ break;
+ case 3: /* 3 means no more channels */
+ goto out;
+ default: /* 1 or 2 should never happened for STSCH */
+ report(0, "Unexpected cc=%d on subchannel number 0x%x",
+ cc, scn);
+ return;
+ }
+
+ /* We currently only support type 0, a.k.a. I/O channels */
+ if (PMCW_CHANNEL_TYPE(pmcw) != 0)
+ continue;
+
+ /* We ignore I/O channels without valid devices */
+ scn_found++;
+ if (!(pmcw->flags & PMCW_DNV))
+ continue;
+
+ /* We keep track of the first device as our test device */
+ if (!test_device_sid)
+ test_device_sid = scn | SID_ONE;
+
+ dev_found++;
+ }
+
+out:
+ report(dev_found,
+ "Tested subchannels: %d, I/O subchannels: %d, I/O devices: %d",
+ scn, scn_found, dev_found);
Just wondering: with the current invocation, you expect to find exactly
one subchannel with a valid device, right?
...snip...
diff --git a/s390x/unittests.cfg b/s390x/unittests.cfg
index 07013b2..a436ec0 100644
--- a/s390x/unittests.cfg
+++ b/s390x/unittests.cfg
@@ -83,3 +83,7 @@ extra_params = -m 1G
[sclp-3g]
file = sclp.elf
extra_params = -m 3G
+
+[css]
+file = css.elf
+extra_params =-device ccw-pong
Hm... you could test enumeration even with a QEMU that does not include
support for the pong device, right? Would it be worthwhile to split out
a set of css tests that use e.g. a virtio-net-ccw device, and have a
css-pong set of tests that require the pong device?
Yes, you are right, using a virtio-net-ccw will allow to keep this test
without waiting for the PONG device to exist.
@Thomas, what do you think? I will still have to figure something out
for PONG tests but here, it should be OK with virtio-net-ccw.
Thanks a lot for the solution, :)
Regards,
Pierre
--
Pierre Morel
IBM Lab Boeblingen
