From NetBSD:

remove floating point expressions.  gen_cvtab.c generates a conversion
table to replace a specific floating point expression in grf_cv.c

3 files changed, 105 insertions, 9 deletions

diff --git a/sys/arch/amiga/dev/gen_cvtab.c b/sys/arch/amiga/dev/gen_cvtab.c
new file mode 100644
index 00000000000..a78f9e4c867
--- /dev/null
+++ b/sys/arch/amiga/dev/gen_cvtab.c
@@ -0,0 +1,66 @@
+/*	$OpenBSD: gen_cvtab.c,v 1.1 1996/02/26 21:08:03 niklas Exp $	*/
+/*	$NetBSD: gen_cvtab.c,v 1.1 1996/02/24 20:13:00 chopps Exp $	*/
+
+/*
+ * Copyright (c) 1996 Christian E. Hopps
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *      This product includes software developed by Christian E. Hopps.
+ * 4. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#include <sys/types.h>
+#include <stdio.h>
+
+/*
+ * generate a conversion table to replace the use of the
+ * floating point expression below in grf_cv.c
+ */
+int
+main(int argc, char** argv)
+{
+	u_long vals[31];
+	u_long clock;
+	int m = 33;
+	int lastm = -1;
+
+	for (clock = 0; clock < 1080 && m > 0; ++clock) {
+		m = ((55 * .72 + 16.867) * 89.736 / (clock + 39) - 21.1543);	
+		m = m / 2 - 1;
+		if (m > 31)
+			continue;
+		if (m != lastm)  {
+			vals[m] = clock;
+			lastm = m;
+		}
+	}
+	printf("/* generated by gen_cvtab */\n");
+	printf("static int cv_convtab[31] = {");
+	for (m = 0; m < 31; ++m) {
+		if (m % 5 == 0)
+			printf("\n");
+		printf("\t%ld,", vals[m]);
+	}
+	printf("\n};\n");
+}
diff --git a/sys/arch/amiga/dev/grf_cv.c b/sys/arch/amiga/dev/grf_cv.c
index 2e8e0a78057..ea2cf5f15ab 100644
--- a/sys/arch/amiga/dev/grf_cv.c
+++ b/sys/arch/amiga/dev/grf_cv.c
@@ -1,4 +1,5 @@
-/*	$NetBSD: grf_cv.c,v 1.5 1995/12/27 07:15:53 chopps Exp $	*/
+/*	$OpenBSD: grf_cv.c,v 1.5 1996/02/26 21:08:00 niklas Exp $	*/
+/*	$NetBSD: grf_cv.c,v 1.6 1996/02/24 20:13:01 chopps Exp $	*/
 
 /*
  * Copyright (c) 1995 Michael Teske
@@ -109,6 +110,16 @@ static struct grfvideo_mode monitor_def[8] = {
 static struct grfvideo_mode *monitor_current = &monitor_def[0];
 #define MAXPIXELCLOCK 135000000 /* safety */
 
+/* generated by gen_cvtab.c */
+static int cv_convtab[31] = {
+	163,	148,	135,	124,	114,
+	106,	98,	91,	85,	79,
+	74,	69,	65,	61,	57,
+	53,	50,	47,	44,	42,
+	39,	37,	35,	33,	31,
+	29,	27,	26,	24,	22,
+	21,
+};
 
 /* Console display definition.
  *   Default hardcoded text mode.  This grf_cv is set up to
@@ -885,7 +896,7 @@ cv_load_mon(gp, md)
 	char LACE, DBLSCAN, TEXT;
 	int uplim, lowlim;
 	int cr33, sr15, sr18, clock_mode, test;
-	int m, n, clock;	/* For calc'ing display FIFO */
+	int m, n, clock, i;	/* For calc'ing display FIFO */
 
 	/* identity */
 	gv = &md->gv;
@@ -1124,20 +1135,31 @@ cv_load_mon(gp, md)
 
 	n = 0xff;
 	if (gv->depth < 9)
-		clock = gv->pixel_clock / 500000.0;
+		clock = gv->pixel_clock / 500000;
 	else if (gv->depth == 15)
-		clock = gv->pixel_clock / 250000.0;
+		clock = gv->pixel_clock / 250000;
 	else
-		clock = (gv->pixel_clock * (gv->depth / 8)) / 500000.0;
-
-	m = ((int)((55 * .72 + 16.867) * 89.736 / (clock + 39) - 21.1543) / 2) - 1;
-
+		clock = (gv->pixel_clock * (gv->depth / 8)) / 500000;
+#if 0
+	/*
+	 * Note: if you change this you should change it in
+	 * gen_cvtab.c and regenerate the conversion table
+	 * rerun gen_cvtab
+	 */
+	m = (int)((55 * .72 + 16.867) * 89.736 / (clock + 39) - 21.1543)
+	m = (m / 2) - 1;
 	if (m > 31)
 		m = 31;
 	else if (m <= 0) {
 		m = 0;
 		n = 16;
 	}
+#endif
+	for (m = 0; m < 31; ++m)
+		if (clock >= cv_convtab[m])
+			break;
+	if (m == 0)
+		n = 16;
 
 	m = m << 3;
 	WCrt(ba, CRT_ID_EXT_MEM_CNTL_2, m);
diff --git a/sys/arch/amiga/dev/sfas.c b/sys/arch/amiga/dev/sfas.c
index 5e9eedaafba..06e483a5a04 100644
--- a/sys/arch/amiga/dev/sfas.c
+++ b/sys/arch/amiga/dev/sfas.c
@@ -1,3 +1,5 @@
+/*    $OpenBSD: sfas.c,v 1.4 1996/02/26 21:08:02 niklas Exp $  */
+
 /*
  * Copyright (c) 1995 Daniel Widenfalk
  * Copyright (c) 1994 Christian E. Hopps
@@ -165,9 +167,15 @@ sfasinitialize(dev)
 	dev->sc_config2 = SFAS_CFG2_FEATURES_ENABLE;
 	dev->sc_config3 = (dev->sc_clock_freq > 25 ? SFAS_CFG3_FASTCLK : 0);
 
-/* Precalculate timeout value and clock period. */
+#if 0	/* don't use floating point */
 	dev->sc_timeout_val  = 1+dev->sc_timeout*dev->sc_clock_freq/
 				 (7.682*dev->sc_clock_conv_fact);
+#endif
+	/* Precalculate timeout value and clock period. */
+	dev->sc_timeout_val  = 1 +
+	    (dev->sc_timeout * dev->sc_clock_freq * 1000)
+	    / (7682 * dev->sc_clock_conv_fact);
+
 	dev->sc_clock_period = 1000/dev->sc_clock_freq;
 
 	sfasreset(dev, 1 | 2);	/* Reset Chip and Bus */