4 files changed, 43 insertions(+), 26 deletions(-)

M pc/devvga.c
M power/l.s
M power/main.c
M power/trap.c

@@ 103,6 103,7 @@ VGAmode mode13 =
 static	Rectangle mbb;
 static	Rectangle NULLMBB = {10000, 10000, -10000, -10000};
 static	void nopage(int), tsengpage(int), tridentpage(int), parapage(int);
+static	void atipage(int);
 static	void vgaupdate(void);
 
 /*


@@ 124,9 125,9 @@ enum
 	Generic,
 };
 
-Vgacard vgacards[] =
+Vgacard vgachips[] =
 {
-[Ati]		{ "ati", nopage, },
+[Ati]		{ "ati", atipage, },
 [Pvga1a]	{ "pvga1a", parapage, },
 [Trident]	{ "trident", tridentpage, },
 [Tseng]		{ "tseng", tsengpage, },


@@ 145,7 146,7 @@ enum
 	Qvgasize=	1,
 	Qvgatype=	2,
 	Qvgaport=	3,
-	Nvga=		4,
+	Nvga=		3,
 };
 Dirtab vgadir[]={
 	"vgasize",	{Qvgasize},	0,		0666,


@@ 156,7 157,7 @@ Dirtab vgadir[]={
 void
 vgareset(void)
 {
-	vgacard = &vgacards[Generic];
+	vgacard = &vgachips[Generic];
 }
 
 void


@@ 253,7 254,7 @@ vgawrite(Chan *c, void *buf, long n, ulong offset)
 		cbuf[n] = 0;
 		if(cp = strchr(cbuf, '\n'))
 			*cp = 0;
-		for(vp = vgacards; vp->name; vp++)
+		for(vp = vgachips; vp->name; vp++)
 			if(strcmp(cbuf, vp->name) == 0){
 				vgacard = vp;
 				return n;


@@ 629,10 630,26 @@ nopage(int page)
 {
 	USED(page);
 }
+/*
+ * The following code is unproven: we haven't got the
+ * ATI stuff to work yet.
+ */
+static void
+atipage(int page)
+{
+	/* the ext register is in the ATI ROM at a fixed address */
+	ushort extreg = *((ushort *)0x800C0010);
+	uchar v;
+
+	outb(extreg, 0xb2);
+	v = (inb(extreg+1) & 0xe1) | (page<<1);
+	outb(extreg, 0xb2);
+	outb(extreg+1, v);
+}
 static void
 tridentpage(int page)
 {
-	srout(0x0e, page^0x02);	/* yes, the page bit needs to be toggled! */
+	srout(0x0e, page^0x02);
 }
 static void
 tsengpage(int page)

@@ 493,19 493,18 @@ TEXT	clrfpintr(SB), $0
 	OR	$CU1, R3
 	MOVW	R3, M(STATUS)
 	WAIT
-
-	MOVW	FCR31, R1
-	MOVW	R1, R2
-	AND	$~(0x3F<<12), R2
-	MOVW	R2, FCR31
-
+	MOVW	FCR31, R1		/* Read it to stall the fpu */
+	WAIT
+	MOVW	R0, FCR31
+	WAIT
 	AND	$~CU1, R3
 	MOVW	R3, M(STATUS)
 	RET
 
 TEXT	savefpregs(SB), $0
 	MOVW	M(STATUS), R3
-	MOVW	FCR31, R2
+	MOVW	FCR31, R2		/* Read stalls the fpu until inst. complete. */
+	WAIT
 
 	MOVD	F0, 0x00(R1)
 	MOVD	F2, 0x08(R1)


@@ 523,6 522,7 @@ TEXT	savefpregs(SB), $0
 	MOVD	F26, 0x68(R1)
 	MOVD	F28, 0x70(R1)
 	MOVD	F30, 0x78(R1)
+	WAIT
 
 	MOVW	R2, 0x80(R1)
 	AND	$~CU1, R3

@@ 537,7 537,7 @@ confinit(void)
 	/*
 	 *  set minimal default values
 	 */
-	conf.nmach = 1;
+	conf.nmach = 2;
 	conf.nproc = 100;
 	conf.nswap = 262144;
 	conf.nimage = 200;

@@ 76,18 76,18 @@ m->ur = ur;
 
 	ecode = (ur->cause>>2)&0xf;
 	user = ur->status&KUP;
-	if(user)
-		u->dbgreg = ur;
-
 	fpchk = 0;
-	if(u && u->p->fpstate == FPactive) {
-		if((ur->status&CU1) == 0)		/* Paranoid */
-			panic("FPactive but no CU1");
-		u->p->fpstate = FPinactive;
-		ur->status &= ~CU1;
-		savefpregs(&u->fpsave);
-		fptrap(ur);
-		fpchk = 1;
+	if(user) {
+		u->dbgreg = ur;
+		if(u->p->fpstate == FPactive) {
+			if((ur->status&CU1) == 0)		/* Paranoid */
+				panic("FPactive but no CU1");
+			u->p->fpstate = FPinactive;
+			ur->status &= ~CU1;
+			savefpregs(&u->fpsave);
+			fptrap(ur);
+			fpchk = 1;
+		}
 	}
 
 	switch(ecode){


@@ 115,7 115,7 @@ m->ur = ur;
 
 	case CCPU:
 		cop = (ur->cause>>28)&3;
-		if(user && u && cop == 1) {
+		if(user && cop == 1) {
 			if(u->p->fpstate == FPinit) {
 				u->p->fpstate = FPinactive;
 				fcr31 = u->fpsave.fpstatus;