From f3e78e417fdafa4b145c67c819c6c1e9512d1195 Mon Sep 17 00:00:00 2001
From: Brett Gordon <beretta42@gmail.com>
Date: Wed, 23 Mar 2016 09:12:22 -0400
Subject: [PATCH] coco3: dwtime: fake a ___mulsi3 and use to simplify code.

---
 Kernel/platform-coco3/dwtime.c | 126 ++++++++++-----------------------
 1 file changed, 38 insertions(+), 88 deletions(-)

diff --git a/Kernel/platform-coco3/dwtime.c b/Kernel/platform-coco3/dwtime.c
index 4d4e2237..becfccac 100644
--- a/Kernel/platform-coco3/dwtime.c
+++ b/Kernel/platform-coco3/dwtime.c
@@ -3,16 +3,11 @@
 #include <kernel.h>
 #include <drivewire.h>
 #include <printf.h>
+#include <kdata.h>
 
 #define DISC __attribute__((section(".discard")))
 
 
-struct my_uint32_t {
-	uint16_t hi;
-	uint16_t low;
-};
-
-
 
 static const uint16_t mktime_moffset[12]= { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 };
 
@@ -28,65 +23,27 @@ static int get_time( char *tbuf )
 }
 
 
-/* shift 32 to left */
-DISC void shift_left ( struct my_uint32_t *a )
-{
-	uint16_t test=a->low & 0x8000;
-	a->low <<= 1;
-	a->hi <<= 1;
-	if( test ) a->hi |= 1;
-	return;
-}
-
-/* accumulate b into a */
-DISC void acc( struct my_uint32_t *a, struct my_uint32_t *b )
-{
-	uint16_t t;
-	t = a->low + b->low;
-	if( t < a->low || t < b->low )
-		a->hi += 1;
-	a->low = t;
-	a->hi = a->hi + b->hi;
-}
-
-DISC void acc0( struct my_uint32_t *b )
-{
-	memset( b, 0, sizeof( struct my_uint32_t ) );
-}
-
-
-
-DISC void multiply_8x32( int8_t a, struct my_uint32_t *b)
+/* A Clasic, as stolen from Gnu */
+uint32_t __mulsi3( uint32_t a, uint32_t b)
 {
-	struct my_uint32_t r;
-	acc0( &r );
+	uint32_t r=0;
 	while (a)
 		{
 			if (a & 1)
-				acc( &r, b );
+				r += b;
 			a >>= 1;
-			shift_left( b );
+			b <<= 1;
 		}
-	memcpy( b, &r, sizeof( struct my_uint32_t ) );
+	b=r;
+	return b;	
 }
 
-DISC void acc16( struct my_uint32_t *a, int16_t b )
-{
-	uint16_t t;
-	t = b + a->low;
-	if( t < b || t < a->low )
-		a->hi += 1;
-	a->low = t ;
-}
 
 
 DISC int dwtime_init( void )
 {
 	char buffer[6];
-	struct my_uint32_t tbuf;
-	struct my_uint32_t *tptr=&tbuf;
-
-	acc0( tptr );
+	uint32_t ret;
 
 	/* get time packet */
 	if ( get_time( buffer ) ) return -1;
@@ -102,52 +59,45 @@ DISC int dwtime_init( void )
 
 	if(year < 70)
 		year += 100;
-	
-	/* following code is based on utc_mktime() from ELKS 
-	   https://github.com/jbruchon/elks/blob/master/elkscmd/sh_utils/date.c */
-	
+
+	/* following code is based on utc_mktime() from ELKS
+	   https://github.com/jbruchon/elks/blob/master/elkscmd/sh_utils/date.c 
+	*/
+
 	/* uses zero-based month index */
 	month--;
-	
+
 	/* calculate days from years */
-	tbuf.low=365;
-	multiply_8x32(year - 70, tptr);
-	
+	ret=365;
+	ret *= year - 70;
+
 	/* count leap days in preceding years */
-	acc16( tptr, (year - 69) >> 2 );
-	
+	ret += (year - 69) >> 2;
+
 	/* calculate days from months */
-	acc16( tptr,  mktime_moffset[month] );
-	
+	ret += mktime_moffset[month];
+
 	/* add in this year's leap day, if any */
-	if (((year & 3) == 0) && (month > 1)) {
-		acc16( tptr, 1 );
-	}
-	
+	if (((year & 3) == 0) && (month > 1)) 
+		ret++;
+
 	/* add in days in this month */
-	acc16( tptr, day - 1);
+	ret += day - 1;
 	/* convert to hours */
-	multiply_8x32(24, tptr);
-	acc16( tptr, hour);
-	
+	ret *= 24;
+	ret += hour;
+
 	/* convert to minutes */
-	multiply_8x32(60, tptr);
-	acc16( tptr, minute);
-	
+	ret *= 60;
+	ret += minute;
+
 	/* convert to seconds */
-	multiply_8x32(60, tptr);
-	acc16( tptr, second);
-	
-
-	/* Set Kernel's TOD */
-	{
-		uint16_t tod[4];
-		tod[0]=tbuf.hi;
-		tod[1]=tbuf.low;
-		tod[2]=0;
-		tod[3]=0;
-		wrtime((time_t *)tod);
-	}
+	ret *= 60;
+	ret += second;
+
+	tod.low=ret;
+	tod.high=0;
+
 	return 0;
 }
 
-- 
2.34.1