From: ian <ian>
Date: Mon, 19 Dec 2005 11:58:38 +0000 (+0000)
Subject: compute cycles etc. in perl, not asm ifdefs (wip)
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ijackson/git?a=commitdiff_plain;h=9e09060e61511124d6bf081c622fe4c524147521;p=trains.git

compute cycles etc. in perl, not asm ifdefs (wip)
---

diff --git a/detpic/Makefile b/detpic/Makefile
index 9617b97..3636637 100644
--- a/detpic/Makefile
+++ b/detpic/Makefile
@@ -33,6 +33,6 @@ syncwrite.asm:	../iwjpictest/syncwrite.asm
 		cp $< $@
 
 %+clocks.inc:	make-clocks %.clocks
-		./$+ $o
+		./$+ $(CLOCKS) $o
 
 clean:		manypic-clean
diff --git a/detpic/make-clocks b/detpic/make-clocks
index a121e62..b8708b1 100755
--- a/detpic/make-clocks
+++ b/detpic/make-clocks
@@ -3,6 +3,14 @@
 use strict qw(vars);
 use POSIX;
 
+our (%defs);
+while ($ARGV[$#ARGV] =~ m/^\-/) {
+    $_ = pop @argv;
+    last if m/^\-\-$/;
+    die unless m/^\-D(\w+)\=(\w+)$/;
+    $defs{$1}= $2;
+}
+
 our ($name,$ms,$interval,$msclock);
 # $interval is in seconds
 # mclock or sclock is in kHz
@@ -17,19 +25,19 @@ sub p ($) { print $_[0] or die $!; }
 
 sub scaleable ($$$$$) {
     my ($width, $foscscale, $scalebitnums, $scales, $deadcycles) = @_;
-    my ($maxcycles, $scalespec, $scalebits, $maxmsclock);
-    my ($lastmaxmsclock, $cycles_per_msclock, $cyclesexpr, @scalebits);
-    my ($prescale, $shift);
+    my ($maxcycles, $scalespec, $scalebits);
+    my ($cycles, $cyequ, @scalebits);
+    my ($prescale);
     $maxcycles = (1 << $width) - $deadcycles;
     foreach $scalespec (@$scales) {
 	$scalespec =~ m/^(\d+)\:([01]+)$/;
 	($prescale,$scalebits) = ($1,$2);
 	length($scalebits) == @$scalebitnums
 	    or die "$scalespec @$scalebitnums";
-	$maxmsclock= floor($maxcycles * $prescale / ($foscscale * $interval));
-	p(" if");
-	p(" $msclock > $lastmaxmsclock &&") if defined $lastmaxmsclock;
-	p(" $msclock <= $maxmsclock\n");
+
+	$cycles= $interval * $foscscale * $msclock / $prescale;
+	next if $cycles > $maxcycles;
+
 	if (length($scalebits)) {
 	    p("${name}scale equ ");
 	    @scalebits = (map { "(1<<$_)" }
@@ -39,26 +47,20 @@ sub scaleable ($$$$$) {
 	    p(join '|', @scalebits);
 	    p("; $prescale:1\n");
 	}
-	$cycles_per_msclock = $interval * $foscscale / $prescale;
-	$shift = 31 - ceil(log($maxmsclock * $cycles_per_msclock) / log(2.0));
-	p(sprintf "%scycles equ (%s * %d) >> %d\n",
-	  $name, $msclock, $cycles_per_msclock * (1<<$shift), $shift);
-	$cyclesexpr= sprintf("(%d - %scycles)",
-			     (1<<$width) - $deadcycles, $name);
+
+	$cyequ= "${name}cycles";
+	p(sprintf "%s equ %d\n", $cyequ, $cycles);
 	if ($width == 16) {
-	    p("${name}inith equ $cyclesexpr / 256\n");
-	    p("${name}initl equ $cyclesexpr & 255\n");
+	    p("${name}inith equ $cyequ / 256\n");
+	    p("${name}initl equ $cyequ & 255\n");
 	} elsif ($width == 8) {
-	    p("${name}init equ $cyclesexpr\n");
+	    p("${name}init equ $cyequ\n");
 	} else {
 	    die "$width";
 	}
-	p(" endif\n");
-	$lastmaxmsclock= $maxmsclock;
+	return;
     }
-    p(" if $msclock > $lastmaxmsclock\n");
-    p("  error \"clock speed too high for $name\"\n");
-    p(" endif\n");
+    warn "clock speed too high for $name\n";
 }
 
 sub do_T13ov ($) {
@@ -98,6 +100,8 @@ sub doline () {
     foreach $ms (qw(m s)) {
 	next unless $mswant =~ m/$ms/i;
 	$msclock= "${ms}clock";
+	die $msclock unless exists $defs{$msclock};
+	$msclock= $defs{$msclock};
 	$name = $orgname.'_'.($ms eq 'm' ? 'master' : 'slave');
 	p(";---------- $name ----------\n");
 	&{ "do_$how" };