[kvm-unit-tests PATCH v2 9/9] s390x: css: ping pong

Pierre Morel
2019-11-28T12:46:26Z

To test a write command with the SSCH instruction we need a QEMU device,
with control unit type 0xC0CA. The PONG device is such a device.

This type of device respond to PONG_WRITE requests by incrementing an
integer, stored as a string at offset 0 of the CCW data.

This is only a success test, no error expected.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
---
s390x/css.c | 46 +++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 45 insertions(+), 1 deletion(-)

diff --git a/s390x/css.c b/s390x/css.c
index 534864f..0761e70 100644
--- a/s390x/css.c
+++ b/s390x/css.c
@@ -23,6 +23,10 @@
#define SID_ONE 0x00010000
#define PSW_PRG_MASK (PSW_MASK_IO | PSW_MASK_EA | PSW_MASK_BA)

+/* Local Channel Commands */
+#define PONG_WRITE 0x21 /* Write */
+#define PONG_READ 0x22 /* Read buffer */
+
struct lowcore *lowcore = (void *)0x0;

static struct schib schib;
@@ -31,7 +35,8 @@ static struct ccw ccw[NB_CCW];
#define NB_ORB 100
static struct orb orb[NB_ORB];
static struct irb irb;
-static char buffer[0x1000] __attribute__ ((aligned(8)));
+#define BUF_SZ 0x1000
+static char buffer[BUF_SZ] __attribute__ ((aligned(8)));
static struct senseid senseid;

static const char *Channel_type[3] = {
@@ -224,6 +229,44 @@ static void test_sense(void)
report("cu_type: expect c0ca, got %04x", 0, senseid.cu_type);
}

+static void test_ping(void)
+{
+ int success, result;
+ int cnt = 0, max = 4;
+
+ if (senseid.cu_type != PONG_CU) {
+ report_skip("No PONG, no ping-pong");
+ return;
+ }
+
+ enable_io_irq();
+
+ while (cnt++ < max) {
+report_info("cnt..: %08x", cnt);
+ snprintf(buffer, BUF_SZ, "%08x\n", cnt);
+ success = start_subchannel(PONG_WRITE, buffer, 8);
+ if (!success) {
+ report("start_subchannel failed", 0);
+ return;
+ }
+ delay(100);
+ success = start_subchannel(PONG_READ, buffer, 8);
+ if (!success) {
+ report("start_subchannel failed", 0);
+ return;
+ }
+ result = atol(buffer);
+ if (result != (cnt + 1)) {
+ report("Bad answer from pong: %08x - %08x", 0, cnt, result);
+ return;
+ } else
+ report_info("%08x - %08x", cnt, result);
+
+ delay(100);
+ }
+ report("ping-pong count 0x%08x", 1, cnt);
+}
+
static struct {
const char *name;
void (*func)(void);
@@ -231,6 +274,7 @@ static struct {
{ "enumerate (stsch)", test_enumerate },
{ "enable (msch)", test_enable },
{ "sense (ssch/tsch)", test_sense },
+ { "ping-pong (ssch/tsch)", test_ping },
{ NULL, NULL }
};

--
2.17.0