ide-test: cdrom_pio_impl fixup

Final tidying: move the interrupt wait into the loop,
document that the status read clears the IRQ, and move
the final interrupt check outside of the loop.

This should be functionally equivalent to how it works
currently, but a little less ambiguous and slightly more
explicit about the state transitions.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1448060035-31973-3-git-send-email-jsnow@redhat.com

1 files changed, 11 insertions, 5 deletions

diff --git a/tests/ide-test.c b/tests/ide-test.c
index fc1ce52..46763db 100644
--- a/tests/ide-test.c
+++ b/tests/ide-test.c
@@ -709,9 +709,6 @@ static void cdrom_pio_impl(int nblocks)
     /* SCSI CDB (READ10) -- read n*2048 bytes from block 0 */
     send_scsi_cdb_read10(0, nblocks);
 
-    /* HP3: INTRQ_Wait */
-    ide_wait_intr(IDE_PRIMARY_IRQ);
-
     /* Read data back: occurs in bursts of 'BYTE_COUNT_LIMIT' bytes.
      * If BYTE_COUNT_LIMIT is odd, we transfer BYTE_COUNT_LIMIT - 1 bytes.
      * We allow an odd limit only when the remaining transfer size is
@@ -723,16 +720,25 @@ static void cdrom_pio_impl(int nblocks)
     for (i = 0; i < DIV_ROUND_UP(rxsize, limit); i++) {
         size_t offset = i * (limit / 2);
         size_t rem = (rxsize / 2) - offset;
-        /* HP2: Check_Status_B */
+
+        /* HP3: INTRQ_Wait */
+        ide_wait_intr(IDE_PRIMARY_IRQ);
+
+        /* HP2: Check_Status_B (and clear IRQ) */
         data = ide_wait_clear(BSY);
         assert_bit_set(data, DRQ | DRDY);
         assert_bit_clear(data, ERR | DF | BSY);
+
         /* HP4: Transfer_Data */
         for (j = 0; j < MIN((limit / 2), rem); j++) {
             rx[offset + j] = le16_to_cpu(inw(IDE_BASE + reg_data));
         }
-        ide_wait_intr(IDE_PRIMARY_IRQ);
     }
+
+    /* Check for final completion IRQ */
+    ide_wait_intr(IDE_PRIMARY_IRQ);
+
+    /* Sanity check final state */
     data = ide_wait_clear(DRQ);
     assert_bit_set(data, DRDY);
     assert_bit_clear(data, DRQ | ERR | DF | BSY);