From 02abe246889398a108a3f92428b9f1f87e32de81 Mon Sep 17 00:00:00 2001
From: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Date: Thu, 4 Mar 2021 22:10:46 +0000
Subject: [PATCH] esp: remove CMD pdma_origin
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The cmdbuf is really just a copy of FIFO data (including extra message phase
bytes) so its pdma_origin is effectively TI. Fortunately we already know when
we are receiving a SCSI command since do_cmd == 1 which enables us to
distinguish between the two cases in esp_pdma_read()/esp_pdma_write().

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20210304221103.6369-26-mark.cave-ayland@ilande.co.uk>
---
 hw/scsi/esp.c         | 22 ++++++++++++----------
 include/hw/scsi/esp.h |  1 -
 2 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/hw/scsi/esp.c b/hw/scsi/esp.c
index c80dc606e8..d5c03f9697 100644
--- a/hw/scsi/esp.c
+++ b/hw/scsi/esp.c
@@ -143,10 +143,11 @@ static uint8_t esp_pdma_read(ESPState *s)
 
     switch (s->pdma_origin) {
     case TI:
-        val = s->ti_buf[s->ti_rptr++];
-        break;
-    case CMD:
-        val = s->cmdbuf[s->cmdlen++];
+        if (s->do_cmd) {
+            val = s->cmdbuf[s->cmdlen++];
+        } else {
+            val = s->ti_buf[s->ti_rptr++];
+        }
         break;
     case ASYNC:
         val = s->async_buf[0];
@@ -176,10 +177,11 @@ static void esp_pdma_write(ESPState *s, uint8_t val)
 
     switch (s->pdma_origin) {
     case TI:
-        s->ti_buf[s->ti_wptr++] = val;
-        break;
-    case CMD:
-        s->cmdbuf[s->cmdlen++] = val;
+        if (s->do_cmd) {
+            s->cmdbuf[s->cmdlen++] = val;
+        } else {
+            s->ti_buf[s->ti_wptr++] = val;
+        }
         break;
     case ASYNC:
         s->async_buf[0] = val;
@@ -240,7 +242,7 @@ static uint32_t get_cmd(ESPState *s)
         if (s->dma_memory_read) {
             s->dma_memory_read(s->dma_opaque, buf, dmalen);
         } else {
-            set_pdma(s, CMD);
+            set_pdma(s, TI);
             esp_raise_drq(s);
             return 0;
         }
@@ -471,7 +473,7 @@ static void esp_do_dma(ESPState *s)
         if (s->dma_memory_read) {
             s->dma_memory_read(s->dma_opaque, &s->cmdbuf[s->cmdlen], len);
         } else {
-            set_pdma(s, CMD);
+            set_pdma(s, TI);
             s->pdma_cb = do_dma_pdma_cb;
             esp_raise_drq(s);
             return;
diff --git a/include/hw/scsi/esp.h b/include/hw/scsi/esp.h
index 1be4586aff..dbbbb3fc52 100644
--- a/include/hw/scsi/esp.h
+++ b/include/hw/scsi/esp.h
@@ -17,7 +17,6 @@ typedef struct ESPState ESPState;
 
 enum pdma_origin_id {
     TI,
-    CMD,
     ASYNC,
 };
 
-- 
2.11.0