From 253f3bc660d946ec005b3997c104657bac1ff1bc Mon Sep 17 00:00:00 2001
From: steve <steve>
Date: Thu, 26 Jun 2003 03:57:05 +0000
Subject: [PATCH]  Add Xilinx support for A/B MUX devices.

---
 tgt-fpga/d-virtex.c  |  7 ++++--
 tgt-fpga/d-virtex2.c |  7 ++++--
 tgt-fpga/xilinx.c    | 55 +++++++++++++++++++++++++++++++++++++++++++-
 tgt-fpga/xilinx.h    |  6 ++++-
 4 files changed, 69 insertions(+), 6 deletions(-)

diff --git a/tgt-fpga/d-virtex.c b/tgt-fpga/d-virtex.c
index f3dda88ca..90bbbe920 100644
--- a/tgt-fpga/d-virtex.c
+++ b/tgt-fpga/d-virtex.c
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #ifdef HAVE_CVS_IDENT
-#ident "$Id: d-virtex.c,v 1.25 2003/06/25 02:55:57 steve Exp $"
+#ident "$Id: d-virtex.c,v 1.26 2003/06/26 03:57:05 steve Exp $"
 #endif
 
 # include  "device.h"
@@ -670,7 +670,7 @@ const struct device_s d_virtex_edif = {
       virtex_eq,
       virtex_eq,
       virtex_ge,
-      0,
+      xilinx_mux,
       virtex_add,
       virtex_add,
       xilinx_shiftl,
@@ -680,6 +680,9 @@ const struct device_s d_virtex_edif = {
 
 /*
  * $Log: d-virtex.c,v $
+ * Revision 1.26  2003/06/26 03:57:05  steve
+ *  Add Xilinx support for A/B MUX devices.
+ *
  * Revision 1.25  2003/06/25 02:55:57  steve
  *  Virtex and Virtex2 share much code.
  *
diff --git a/tgt-fpga/d-virtex2.c b/tgt-fpga/d-virtex2.c
index 932e0775d..c920e74e1 100644
--- a/tgt-fpga/d-virtex2.c
+++ b/tgt-fpga/d-virtex2.c
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #ifdef HAVE_CVS_IDENT
-#ident "$Id: d-virtex2.c,v 1.14 2003/06/25 02:55:57 steve Exp $"
+#ident "$Id: d-virtex2.c,v 1.15 2003/06/26 03:57:05 steve Exp $"
 #endif
 
 # include  "device.h"
@@ -141,7 +141,7 @@ const struct device_s d_virtex2_edif = {
       virtex_eq,
       virtex_eq,
       virtex_ge,
-      0,
+      xilinx_mux,
       virtex_add,
       virtex_add,
       xilinx_shiftl, /* show_shiftl */
@@ -151,6 +151,9 @@ const struct device_s d_virtex2_edif = {
 
 /*
  * $Log: d-virtex2.c,v $
+ * Revision 1.15  2003/06/26 03:57:05  steve
+ *  Add Xilinx support for A/B MUX devices.
+ *
  * Revision 1.14  2003/06/25 02:55:57  steve
  *  Virtex and Virtex2 share much code.
  *
diff --git a/tgt-fpga/xilinx.c b/tgt-fpga/xilinx.c
index 3219c0a19..a2510ff16 100644
--- a/tgt-fpga/xilinx.c
+++ b/tgt-fpga/xilinx.c
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #ifdef HAVE_CVS_IDENT
-#ident "$Id: xilinx.c,v 1.2 2003/06/25 02:55:57 steve Exp $"
+#ident "$Id: xilinx.c,v 1.3 2003/06/26 03:57:05 steve Exp $"
 #endif
 
 # include  "edif.h"
@@ -485,6 +485,56 @@ void xilinx_logic(ivl_net_logic_t net)
       }
 }
 
+/*
+ * A fully generic Xilinx MUX is implemented entirely from LUT
+ * devices.
+ */
+void xilinx_mux(ivl_lpm_t net)
+{
+      unsigned idx;
+
+      edif_cellref_t lut;
+      edif_joint_t jnt;
+
+      assert(ivl_lpm_selects(net) == 1);
+
+	/* A/B Mux devices are made from LUT3 devices. I0 is connected
+	   to A, I1 to B, and I2 to the Select input. Create as many
+	   as are needed to implement the requested width.
+
+	   S B A | Q
+	   ------+--
+	   0 0 0 | 0
+	   0 0 1 | 1
+	   0 1 0 | 0
+	   0 1 1 | 1
+	   1 0 0 | 0
+	   1 0 1 | 0
+	   1 1 0 | 1
+	   1 1 1 | 1
+
+	   INIT = "CA" */
+
+      for (idx = 0 ;  idx < ivl_lpm_width(net) ;  idx += 1) {
+
+	    lut = edif_cellref_create(edf, xilinx_cell_lut3(xlib));
+
+	    jnt = edif_joint_of_nexus(edf, ivl_lpm_q(net, idx));
+	    edif_add_to_joint(jnt, lut, LUT_O);
+
+	    jnt = edif_joint_of_nexus(edf, ivl_lpm_data2(net, 0, idx));
+	    edif_add_to_joint(jnt, lut, LUT_I0);
+
+	    jnt = edif_joint_of_nexus(edf, ivl_lpm_data2(net, 1, idx));
+	    edif_add_to_joint(jnt, lut, LUT_I1);
+
+	    jnt = edif_joint_of_nexus(edf, ivl_lpm_select(net, 0));
+	    edif_add_to_joint(jnt, lut, LUT_I2);
+
+	    edif_cellref_pstring(lut, "INIT", "CA");
+      }
+}
+
 /*
  * Any Xilinx device works with this adder.
  * Generic Xilinx add only works for single bit slices.
@@ -682,6 +732,9 @@ void xilinx_shiftl(ivl_lpm_t net)
 
 /*
  * $Log: xilinx.c,v $
+ * Revision 1.3  2003/06/26 03:57:05  steve
+ *  Add Xilinx support for A/B MUX devices.
+ *
  * Revision 1.2  2003/06/25 02:55:57  steve
  *  Virtex and Virtex2 share much code.
  *
diff --git a/tgt-fpga/xilinx.h b/tgt-fpga/xilinx.h
index 04fb29dee..26edc6491 100644
--- a/tgt-fpga/xilinx.h
+++ b/tgt-fpga/xilinx.h
@@ -19,7 +19,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #ifdef HAVE_CVS_IDENT
-#ident "$Id: xilinx.h,v 1.2 2003/06/25 02:55:57 steve Exp $"
+#ident "$Id: xilinx.h,v 1.3 2003/06/26 03:57:05 steve Exp $"
 #endif
 
 /*
@@ -104,11 +104,15 @@ extern void virtex_add(ivl_lpm_t net);
 extern void xilinx_show_scope(ivl_scope_t scope);
 extern void xilinx_pad(ivl_signal_t, const char*str);
 extern void xilinx_logic(ivl_net_logic_t net);
+extern void xilinx_mux(ivl_lpm_t net);
 extern void xilinx_add(ivl_lpm_t net);
 extern void xilinx_shiftl(ivl_lpm_t net);
 
 /*
  * $Log: xilinx.h,v $
+ * Revision 1.3  2003/06/26 03:57:05  steve
+ *  Add Xilinx support for A/B MUX devices.
+ *
  * Revision 1.2  2003/06/25 02:55:57  steve
  *  Virtex and Virtex2 share much code.
  *