ivshmem-test: Improve test case /ivshmem/single

Test state of registers after reset.

Test reading Interrupt Status clears it.

Test (invalid) read of Doorbell.

Add more comments.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1458066895-20632-8-git-send-email-armbru@redhat.com>

1 files changed, 16 insertions, 7 deletions

diff --git a/tests/ivshmem-test.c b/tests/ivshmem-test.c
index da6ca0dd9e..a48dc49cd0 100644
--- a/tests/ivshmem-test.c
+++ b/tests/ivshmem-test.c
@@ -143,32 +143,41 @@ static void test_ivshmem_single(void)
     setup_vm(&state);
     s = &state;
 
-    /* valid io */
-    out_reg(s, INTRMASK, 0);
-    in_reg(s, INTRSTATUS);
-    in_reg(s, IVPOSITION);
+    /* initial state of readable registers */
+    g_assert_cmpuint(in_reg(s, INTRMASK), ==, 0);
+    g_assert_cmpuint(in_reg(s, INTRSTATUS), ==, 0);
+    g_assert_cmpuint(in_reg(s, IVPOSITION), ==, 0);
 
+    /* trigger interrupt via registers */
     out_reg(s, INTRMASK, 0xffffffff);
     g_assert_cmpuint(in_reg(s, INTRMASK), ==, 0xffffffff);
     out_reg(s, INTRSTATUS, 1);
-    /* XXX: intercept IRQ, not seen in resp */
+    /* check interrupt status */
     g_assert_cmpuint(in_reg(s, INTRSTATUS), ==, 1);
+    /* reading clears */
+    g_assert_cmpuint(in_reg(s, INTRSTATUS), ==, 0);
+    /* TODO intercept actual interrupt (needs qtest work) */
 
-    /* invalid io */
+    /* invalid register access */
     out_reg(s, IVPOSITION, 1);
+    in_reg(s, DOORBELL);
+
+    /* ring the (non-functional) doorbell */
     out_reg(s, DOORBELL, 8 << 16);
 
+    /* write shared memory */
     for (i = 0; i < G_N_ELEMENTS(data); i++) {
         data[i] = i;
     }
     qtest_memwrite(s->qtest, (uintptr_t)s->mem_base, data, sizeof(data));
 
+    /* verify write */
     for (i = 0; i < G_N_ELEMENTS(data); i++) {
         g_assert_cmpuint(((uint32_t *)tmpshmem)[i], ==, i);
     }
 
+    /* read it back and verify read */
     memset(data, 0, sizeof(data));
-
     qtest_memread(s->qtest, (uintptr_t)s->mem_base, data, sizeof(data));
     for (i = 0; i < G_N_ELEMENTS(data); i++) {
         g_assert_cmpuint(data[i], ==, i);