esp.c: start removal of manual STAT_TC setting when transfer counter …

…reaches zero

This should be exclusively managed by esp_set_tc() rather than being manually
set in multiple places. Start by removing the occurrences exclusive to PDMA
and command completion which are those that can be currently removed without
affecting any test images.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Tested-by: Helge Deller <deller@gmx.de>
Tested-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20240112125420.514425-8-mark.cave-ayland@ilande.co.uk>
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>

hw/scsi/esp.c

@@ -611,11 +611,6 @@ static void do_dma_pdma_cb(ESPState *s)
             s->async_len -= len;
             s->ti_size -= len;
             esp_set_tc(s, esp_get_tc(s) - len);
-
-            if (esp_get_tc(s) == 0) {
-                /* Indicate transfer to FIFO is complete */
-                 s->rregs[ESP_RSTAT] |= STAT_TC;
-            }
             return;
         }
 
@@ -720,9 +715,6 @@ static void esp_do_dma(ESPState *s)
             esp_set_tc(s, esp_get_tc(s) - len);
             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
             esp_raise_drq(s);
-
-            /* Indicate transfer to FIFO is complete */
-            s->rregs[ESP_RSTAT] |= STAT_TC;
             return;
         }
     }
@@ -870,7 +862,8 @@ void esp_command_complete(SCSIRequest *req, size_t resid)
      * transfers from the target the last byte is still in the FIFO
      */
     if (s->ti_size == 0) {
-        s->rregs[ESP_RSTAT] = STAT_TC | STAT_ST;
+        s->rregs[ESP_RSTAT] &= ~7;
+        s->rregs[ESP_RSTAT] |= STAT_ST;
         esp_dma_done(s);
         esp_lower_drq(s);
     }