On 2019-12-02 20:49, Cornelia Huck wrote:
On Mon, 2 Dec 2019 19:33:59 +0100
Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote:
On 2019-12-02 19:15, Cornelia Huck wrote:
On Mon, 2 Dec 2019 18:53:16 +0100
Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote:
On 2019-12-02 15:22, Cornelia Huck wrote:
On Thu, 28 Nov 2019 13:46:04 +0100
Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote:
+static int test_device_sid;
+
+static void test_enumerate(void)
+{
+ struct pmcw *pmcw = &schib.pmcw;
+ int sid;
+ int ret, i;
+ int found = 0;
+
+ for (sid = 0; sid < 0xffff; sid++) {
+ ret = stsch(sid|SID_ONE, &schib);
This seems a bit odd. You are basically putting the subchannel number
into sid, OR in the one, and then use the resulting value as the sid
(subchannel identifier).
+ if (!ret && (pmcw->flags & PMCW_DNV)) {
+ report_info("SID %04x Type %s PIM %x", sid,
That's not a sid, but the subchannel number (see above).
+ Channel_type[pmcw->st], pmcw->pim);
+ for (i = 0; i < 8; i++) {
+ if ((pmcw->pim << i) & 0x80) {
+ report_info("CHPID[%d]: %02x", i,
+ pmcw->chpid[i]);
+ break;
+ }
+ }
+ found++;
+
+ }
Here, you iterate over the 0-0xffff range, even if you got a condition
code 3 (indicating no more subchannels in that set). Is that
intentional?
I thought there could be more subchannels.
I need then a break in the loop when this happens.
I will reread the PoP to see how to find that no more subchannel are in
that set.
The fact that cc 3 for stsch == no more subchannels is unfortunately a
bit scattered across the PoP :/ Dug it out some time ago, maybe it's
still in the archives somewhere...
So the the subchannel are always one after the other?
While QEMU (and z/VM) usually do that, they can really be scattered
around. For the in-between I/O subchannels that don't lead to a device,
you'll still get cc 0, it's just the dnv bit that is 0. The cc 3
basically just tells you that you can stop looking.
Thanks for the explanation, I will change the code accordingly.
Regards,
Pierre
--
Pierre Morel
IBM Lab Boeblingen
