From 5f104d447d6329166c50108701d3021a41e6947d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Arnim=20L=C3=A4uger?= <arniml@users.sourceforge.net>
Date: Thu, 14 Feb 2008 22:44:00 +0000
Subject: [PATCH] flush todo queue for transfers without output capture (if
 conservative flush strategy is not disabled)

git-svn-id: https://urjtag.svn.sourceforge.net/svnroot/urjtag/trunk@1016 b68d4a1b-bc3d-0410-92ed-d4ac073336b7
---
 jtag/ChangeLog       |  6 ++++++
 jtag/configure.ac    | 15 +++++++++++++++
 jtag/include/cable.h |  1 +
 jtag/src/tap/cable.c |  9 +++++++++
 jtag/src/tap/chain.c |  9 +++++++--
 5 files changed, 38 insertions(+), 2 deletions(-)

diff --git a/jtag/ChangeLog b/jtag/ChangeLog
index 072f0b56..dcce6259 100644
--- a/jtag/ChangeLog
+++ b/jtag/ChangeLog
@@ -1,3 +1,9 @@
+2008-02-14  Arnim Laeuger  <arniml@users.sourceforge.net>
+
+    * src/tap/cable.c (cable_flush), src/tap/chain.c (chain_shift_data_registers_mode),
+        include/cable.h, configure.ac: follow conservative flush strategy for transfers
+        without output capture (if not disabled via configure --disable-conservative-flush)
+
 2008-02-14  Kolja Waschk <kawk>
 
     * src/tap/chain.c: Enabled the new^2 implementation in tap_shift_register
diff --git a/jtag/configure.ac b/jtag/configure.ac
index 354a531e..5a602d11 100644
--- a/jtag/configure.ac
+++ b/jtag/configure.ac
@@ -381,6 +381,21 @@ AS_IF([test "x$jim" = xtrue], [
   AM_CONDITIONAL(ENABLE_JIM, false)
 ])
 
+
+dnl Use conservative flush?
+AC_ARG_ENABLE(conservative_flush,
+[  --enable-conservative-flush  Perform conservative queue flushing (default is enabled)],
+[case "${enableval}" in
+   yes) conservative_flush=true ;;
+   no)  conservative_flush=false ;;
+   *)   AC_MSG_ERROR(cab value ${enableval} for --enable-conservative-flush) ;;
+ esac],
+[conservative_flush=true])
+AS_IF([test "x$conservative_flush" = xtrue], [
+  AC_DEFINE(CONSERVATIVE_FLUSH, 1, [define if conservative queue flushing is enabled])
+])
+
+
 AC_OUTPUT
 
 dnl
diff --git a/jtag/include/cable.h b/jtag/include/cable.h
index f6251444..53d4983e 100644
--- a/jtag/include/cable.h
+++ b/jtag/include/cable.h
@@ -38,6 +38,7 @@ typedef struct cable_driver_t cable_driver_t;
 typedef enum
 {
    OPTIONALLY,
+   CONSERVATIVELY,
    TO_OUTPUT,
    COMPLETELY
 }
diff --git a/jtag/src/tap/cable.c b/jtag/src/tap/cable.c
index 2aa51d70..f546cde5 100644
--- a/jtag/src/tap/cable.c
+++ b/jtag/src/tap/cable.c
@@ -142,6 +142,15 @@ cable_init( cable_t *cable )
 void
 cable_flush ( cable_t *cable, cable_flush_amount_t how_much )
 {
+	if (how_much == CONSERVATIVELY)
+	{
+#ifdef CONSERVATIVE_FLUSH
+		how_much = COMPLETELY;
+#else
+		how_much = OPTIONALLY;
+#endif
+	}
+
 	cable->driver->flush( cable, how_much );
 }
 
diff --git a/jtag/src/tap/chain.c b/jtag/src/tap/chain.c
index f6d67f19..9152157b 100644
--- a/jtag/src/tap/chain.c
+++ b/jtag/src/tap/chain.c
@@ -173,7 +173,6 @@ chain_shift_data_registers_mode( chain_t *chain, int capture_output, int capture
 	   shift the data register of each part in the chain one by one */
 
 	for (i = 0; i < ps->len; i++) {
-		puts("tap_defer_shift_register");
 		tap_defer_shift_register( chain, ps->parts[i]->active_instruction->data_register->in,
 				capture_output ? ps->parts[i]->active_instruction->data_register->out : NULL,
 				(i + 1) == ps->len ? exit : EXITMODE_SHIFT );
@@ -182,12 +181,18 @@ chain_shift_data_registers_mode( chain_t *chain, int capture_output, int capture
 	if(capture_output)
 	{
 		for (i = 0; i < ps->len; i++) {
-			puts("tap_shift_register_output");
 			tap_shift_register_output( chain, ps->parts[i]->active_instruction->data_register->in,
 				ps->parts[i]->active_instruction->data_register->out,
 				(i + 1) == ps->len ? exit : EXITMODE_SHIFT );
 		}
 	}
+	else
+	{
+		/* the todo queue should be flushed here when following a conservative strategy
+		   since otherwise transfers without output capture wouldn't be submitted until
+		   a transfer with output capture is executed */
+		cable_flush( chain->cable, CONSERVATIVELY );
+	}
 }
 
 void