[Qemu-devel] [PATCH v1 1/1] xilinx_spips: send dummy only if cmd requires it

[Sai Pavan Boddu <sai.pavan.boddu@xilinx.com>]

For all the commands, which do not have an entry in
xilinx_spips_num_dummies, present logic sends dummy byte when ever we
are in SNOOP_NONE state, fix it to send only if cmd requires them.

Only transmit max of 1 dummy byte(i.e 8 cycles) is a single snoop cycle.
And also convert dummy bytes to cycles (required by m25p80).

Signed-off-by: Sai Pavan Boddu <saipava@xilinx.com>
---
 hw/ssi/xilinx_spips.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/hw/ssi/xilinx_spips.c b/hw/ssi/xilinx_spips.c
index 426f971..8278930 100644
--- a/hw/ssi/xilinx_spips.c
+++ b/hw/ssi/xilinx_spips.c
@@ -627,10 +627,17 @@ static void xilinx_spips_flush_txfifo(XilinxSPIPS *s)
                 tx_rx[i] = tx;
             }
         } else {
-            /* Extract a dummy byte and generate dummy cycles according to the
-             * link state */
             tx = fifo8_pop(&s->tx_fifo);
-            dummy_cycles = 8 / s->link_state;
+            if (s->cmd_dummies > 0) {
+                /* Extract a dummy byte and generate dummy cycles according to
+                 * the link state */
+                 dummy_cycles = (s->cmd_dummies ? 1 : 0) * 8 / s->link_state;
+                 s->cmd_dummies--;
+            } else {
+                for (i = 0; i < num_effective_busses(s); ++i) {
+                    tx_rx[i] = tx;
+                }
+            }
         }
 
         for (i = 0; i < num_effective_busses(s); ++i) {
-- 
2.7.4