plan 9 kernel history: overview | file list | diff list

1999/0415/alphapc/dma.c (diff list | history)

1999/0415/sys/src/9/alphapc/dma.c:9,31 – 1999/0423/sys/src/9/alphapc/dma.c:9,14 (short | long)
1999/0415    
typedef struct DMA	DMA; 
typedef struct DMAxfer	DMAxfer; 
 
enum 
{ 
	/* 
	 *  the byte registers for DMA0 are all one byte apart 
	 */ 
	Dma0=		0x00, 
	Dma0status=	Dma0+0x8,	/* status port */ 
	Dma0reset=	Dma0+0xD,	/* reset port */ 
                 
	/* 
	 *  the byte registers for DMA1 are all two bytes apart (why?) 
	 */ 
	Dma1=		0xC0, 
	Dma1status=	Dma1+2*0x8,	/* status port */ 
	Dma1reset=	Dma1+2*0xD,	/* reset port */ 
}; 
                 
/* 
 *  state of a dma transfer 
 */
1999/0415/sys/src/9/alphapc/dma.c:33,38 – 1999/0423/sys/src/9/alphapc/dma.c:16,22
1999/0415    
{ 
	ulong	bpa;		/* bounce buffer physical address */ 
	void*	bva;		/* bounce buffer virtual address */
1999/0423    
	int	blen;		/* bounce buffer length */
1999/0415    
	void*	va;		/* virtual address destination/src */ 
	long	len;		/* bytes to be transferred */ 
	int	isread;
1999/0415/sys/src/9/alphapc/dma.c:84,112 – 1999/0423/sys/src/9/alphapc/dma.c:68,109
1999/0415    
 *  initialisation routines of any devices which require DMA to ensure 
 *  the allocated bounce buffers are below the 16MB limit. 
 */ 
void 
dmainit(int chan)
1999/0423    
int 
dmainit(int chan, int maxtransfer)
1999/0415    
{ 
	DMA *dp; 
	DMAxfer *xp; 
	ulong v;
1999/0423    
	if(maxtransfer > 64*1024) 
		maxtransfer = 64*1024;
1999/0415    
	dp = &dma[(chan>>2)&1]; 
	chan = chan & 3; 
	xp = &dp->x[chan]; 
	if(xp->bva != nil) 
		return; 
                 
	v = (ulong)xalloc(BY2PG+BY2PG); 
	if(v == 0 || PADDR(v) >= 16*MB){ 
		print("dmainit: chan %d: 0x%luX out of range\n", chan, v); 
		xfree((void*)v); 
		v = 0;
1999/0423    
	if(xp->bva != nil){ 
		if(xp->blen < maxtransfer) 
			return 1; 
		return 0;
1999/0415    
	} 
	xp->bva = (void*)ROUND(v, BY2PG);
1999/0423    
 
	xp->bva = xspanalloc(maxtransfer, BY2PG, 64*1024); 
	if(xp->bva == nil) 
		return 1;
1999/0415    
	xp->bpa = PADDR(xp->bva);
1999/0423    
	if(xp->bpa >= 16*MB){ 
		/* 
		 * This will panic with the current 
		 * implementation of xspanalloc(). 
		xfree(xp->bva); 
		 */ 
		xp->bva = nil; 
		return 1; 
	} 
	xp->blen = maxtransfer;
1999/0415    
	xp->len = 0; 
	xp->isread = 0;
1999/0423    
 
	return 0;
1999/0415    
} 
 
/*
1999/0415/sys/src/9/alphapc/dma.c:133,140 – 1999/0423/sys/src/9/alphapc/dma.c:130,138
1999/0415    
 
	/* 
	 *  if this isn't kernel memory or crossing 64k boundary or above 16 meg 
	 *  use the allocated low memory page.
1999/0423    
	 *  use the bounce buffer.
1999/0415    
	 */
1999/0423    
#ifdef notdef
1999/0415    
	pa = PADDR(va); 
	if((((ulong)va)&0xF0000000) != KZERO 
	|| (pa&0xFFFF0000) != ((pa+len)&0xFFFF0000)
1999/0415/sys/src/9/alphapc/dma.c:141,148 – 1999/0423/sys/src/9/alphapc/dma.c:139,146
1999/0415    
	|| pa >= 16*MB) { 
		if(xp->bva == nil) 
			return -1; 
		if(len > BY2PG) 
			len = BY2PG;
1999/0423    
		if(len > xp->blen) 
			len = xp->blen;
1999/0415    
		if(!isread) 
			memmove(xp->bva, va, len); 
		xp->va = va;
1999/0415/sys/src/9/alphapc/dma.c:152,168 – 1999/0423/sys/src/9/alphapc/dma.c:150,170
1999/0415    
	} 
	else 
		xp->len = 0;
1999/0423    
#else 
	pa = PCIWADDR(va); 
#endif /* notdef */
1999/0415    
 
	/* 
	 * this setup must be atomic 
	 */ 
	ilock(dp); 
	mode = (isread ? 0x44 : 0x48) | chan; 
	outb(dp->mode, mode);	/* single mode dma (give CPU a chance at mem) */ 
	outb(dp->page[chan], pa>>16);
1999/0423    
	ilock(dp);
1999/0415    
	outb(dp->cbp, 0);		/* set count & address to their first byte */
1999/0423    
	outb(dp->mode, mode);	/* single mode dma (give CPU a chance at mem) */
1999/0415    
	outb(dp->addr[chan], pa>>dp->shift);		/* set address */ 
	outb(dp->addr[chan], pa>>(8+dp->shift));
1999/0423    
	outb(dp->page[chan], pa>>16); 
outb(0x400|dp->page[chan], pa>>24);
1999/0415    
	outb(dp->count[chan], (len>>dp->shift)-1);		/* set count */ 
	outb(dp->count[chan], ((len>>dp->shift)-1)>>8); 
	outb(dp->sbm, chan);		/* enable the channel */
1999/0423/sys/src/9/alphapc/dma.c:132,137 – 1999/0424/sys/src/9/alphapc/dma.c:132,138 (short | long)
1999/0415    
	 *  if this isn't kernel memory or crossing 64k boundary or above 16 meg
1999/0423    
	 *  use the bounce buffer.
1999/0415    
	 */
1999/0424    
print("va%lux+", va);
1999/0423    
#ifdef notdef
1999/0415    
	pa = PADDR(va); 
	if((((ulong)va)&0xF0000000) != KZERO
1999/0423/sys/src/9/alphapc/dma.c:151,157 – 1999/0424/sys/src/9/alphapc/dma.c:152,158
1999/0415    
	else 
		xp->len = 0;
1999/0423    
#else 
	pa = PCIWADDR(va);
1999/0424    
	pa = ISAWADDR(va);
1999/0423    
#endif /* notdef */
1999/0415    
 
	/*
1999/0423/sys/src/9/alphapc/dma.c:164,174 – 1999/0424/sys/src/9/alphapc/dma.c:165,176
1999/0415    
	outb(dp->addr[chan], pa>>dp->shift);		/* set address */ 
	outb(dp->addr[chan], pa>>(8+dp->shift));
1999/0423    
	outb(dp->page[chan], pa>>16); 
outb(0x400|dp->page[chan], pa>>24);
1999/0424    
//outb(0x400|dp->page[chan], pa>>24);
1999/0415    
	outb(dp->count[chan], (len>>dp->shift)-1);		/* set count */ 
	outb(dp->count[chan], ((len>>dp->shift)-1)>>8); 
	outb(dp->sbm, chan);		/* enable the channel */ 
	iunlock(dp);
1999/0424    
print("pa%lux+", pa);
1999/0415    
 
	return len; 
}
1999/0423/sys/src/9/alphapc/dma.c:206,211 – 1999/0424/sys/src/9/alphapc/dma.c:208,222
1999/0415    
	ilock(dp); 
	outb(dp->sbm, 4|chan); 
	iunlock(dp);
1999/0424    
 
{ int i; 
outb(dp->cbp, 0); 
i = inb(dp->addr[chan]); 
i |= inb(dp->addr[chan])<<8; 
i |= inb(dp->page[chan])<<16; 
i |= inb(0x400|dp->page[chan])<<24; 
print("X%uX+", i); 
}
1999/0415    
 
	xp = &dp->x[chan]; 
	if(xp->len == 0 || !xp->isread)
1999/0424/sys/src/9/alphapc/dma.c:85,90 – 1999/0501/sys/src/9/alphapc/dma.c:85,91 (short | long)
1999/0423    
			return 1; 
		return 0;
1999/0415    
	}
1999/0501    
outb(dp->mc, 0);
1999/0423    
 
	xp->bva = xspanalloc(maxtransfer, BY2PG, 64*1024); 
	if(xp->bva == nil)
1999/0424/sys/src/9/alphapc/dma.c:126,131 – 1999/0501/sys/src/9/alphapc/dma.c:127,135
1999/0415    
 
	dp = &dma[(chan>>2)&1]; 
	chan = chan & 3;
1999/0501    
//print("va%lux+", va); 
#define tryPCI 
#ifdef notdef
1999/0415    
	xp = &dp->x[chan]; 
 
	/*
1999/0424/sys/src/9/alphapc/dma.c:132,139 – 1999/0501/sys/src/9/alphapc/dma.c:136,141
1999/0415    
	 *  if this isn't kernel memory or crossing 64k boundary or above 16 meg
1999/0423    
	 *  use the bounce buffer.
1999/0415    
	 */
1999/0424    
print("va%lux+", va);
1999/0423    
#ifdef notdef
1999/0415    
	pa = PADDR(va); 
	if((((ulong)va)&0xF0000000) != KZERO 
	|| (pa&0xFFFF0000) != ((pa+len)&0xFFFF0000)
1999/0424/sys/src/9/alphapc/dma.c:151,159 – 1999/0501/sys/src/9/alphapc/dma.c:153,165
1999/0415    
	} 
	else 
		xp->len = 0;
1999/0423    
#else
1999/0424    
	pa = ISAWADDR(va);
1999/0423    
#endif /* notdef */
1999/0501    
#ifdef tryISA 
	pa = ISAWADDR(va); 
#endif /* tryISA */ 
#ifdef tryPCI 
	pa = PCIWADDR(va); 
#endif /* tryPCI */
1999/0415    
 
	/* 
	 * this setup must be atomic
1999/0424/sys/src/9/alphapc/dma.c:165,176 – 1999/0501/sys/src/9/alphapc/dma.c:171,184
1999/0415    
	outb(dp->addr[chan], pa>>dp->shift);		/* set address */ 
	outb(dp->addr[chan], pa>>(8+dp->shift));
1999/0423    
	outb(dp->page[chan], pa>>16);
1999/0424    
//outb(0x400|dp->page[chan], pa>>24);
1999/0501    
#ifdef tryPCI 
	outb(0x400|dp->page[chan], pa>>24); 
#endif /* tryPCI */
1999/0415    
	outb(dp->count[chan], (len>>dp->shift)-1);		/* set count */ 
	outb(dp->count[chan], ((len>>dp->shift)-1)>>8); 
	outb(dp->sbm, chan);		/* enable the channel */ 
	iunlock(dp);
1999/0424    
print("pa%lux+", pa);
1999/0501    
//print("pa%lux+", pa);
1999/0415    
 
	return len; 
}
1999/0424/sys/src/9/alphapc/dma.c:215,221 – 1999/0501/sys/src/9/alphapc/dma.c:223,229
1999/0424    
i |= inb(dp->addr[chan])<<8; 
i |= inb(dp->page[chan])<<16; 
i |= inb(0x400|dp->page[chan])<<24; 
print("X%uX+", i);
1999/0501    
//print("X%uX+", i);
1999/0424    
}
1999/0415    
 
	xp = &dp->x[chan];
1999/0501/sys/src/9/alphapc/dma.c:107,112 – 1999/0504/sys/src/9/alphapc/dma.c:107,142 (short | long)
1999/0423    
	return 0;
1999/0415    
}
1999/0504    
static void 
dmastatus(DMA *dp, int chan) 
{ 
	int a, l, s; 
 
	ilock(dp); 
	outb(dp->cbp, 0); 
	a = inb(dp->addr[chan]); 
	a |= inb(dp->addr[chan])<<8; 
	a |= inb(dp->page[chan])<<16; 
	a |= inb(0x400|dp->page[chan])<<24; 
	outb(dp->cbp, 0); 
	l = inb(dp->count[chan]); 
	l |= inb(dp->count[chan])<<8; 
	s = inb(dp->cmd); 
	iunlock(dp); 
	print("addr %uX len %uX stat %uX\n", a, l, s); 
} 
 
void 
xdmastatus(int chan) 
{ 
	DMA *dp; 
 
	dp = &dma[(chan>>2)&1]; 
	chan = chan & 3; 
 
	dmastatus(dp, chan); 
}
1999/0415    
/* 
 *  setup a dma transfer.  if the destination is not in kernel 
 *  memory, allocate a page for the transfer.
1999/0501/sys/src/9/alphapc/dma.c:174,184 – 1999/0504/sys/src/9/alphapc/dma.c:204,215
1999/0501    
#ifdef tryPCI 
	outb(0x400|dp->page[chan], pa>>24); 
#endif /* tryPCI */
1999/0504    
	outb(dp->cbp, 0);		/* set count & address to their first byte */
1999/0415    
	outb(dp->count[chan], (len>>dp->shift)-1);		/* set count */ 
	outb(dp->count[chan], ((len>>dp->shift)-1)>>8); 
	outb(dp->sbm, chan);		/* enable the channel */ 
	iunlock(dp);
1999/0501    
//print("pa%lux+", pa);
1999/0504    
dmastatus(dp, chan);
1999/0415    
 
	return len; 
}
1999/0501/sys/src/9/alphapc/dma.c:210,215 – 1999/0504/sys/src/9/alphapc/dma.c:241,247
1999/0415    
	dp = &dma[(chan>>2)&1]; 
	chan = chan & 3;
1999/0504    
dmastatus(dp, chan);
1999/0415    
	/* 
	 *  disable the channel 
	 */
1999/0501/sys/src/9/alphapc/dma.c:216,230 – 1999/0504/sys/src/9/alphapc/dma.c:248,253
1999/0415    
	ilock(dp); 
	outb(dp->sbm, 4|chan); 
	iunlock(dp);
1999/0424    
                 
{ int i; 
outb(dp->cbp, 0); 
i = inb(dp->addr[chan]); 
i |= inb(dp->addr[chan])<<8; 
i |= inb(dp->page[chan])<<16; 
i |= inb(0x400|dp->page[chan])<<24;
1999/0501    
//print("X%uX+", i);
1999/0424    
}
1999/0415    
 
	xp = &dp->x[chan]; 
	if(xp->len == 0 || !xp->isread)
1999/0504/sys/src/9/alphapc/dma.c:108,114 – 1999/0505/sys/src/9/alphapc/dma.c:108,114 (short | long)
1999/0415    
}
1999/0504    
static void 
dmastatus(DMA *dp, int chan)
1999/0505    
dmastatus(DMA *dp, int chan, char c)
1999/0504    
{ 
	int a, l, s;
1999/0504/sys/src/9/alphapc/dma.c:123,129 – 1999/0505/sys/src/9/alphapc/dma.c:123,129
1999/0504    
	l |= inb(dp->count[chan])<<8; 
	s = inb(dp->cmd); 
	iunlock(dp); 
	print("addr %uX len %uX stat %uX\n", a, l, s);
1999/0505    
	print("%c: addr %uX len %uX stat %uX\n", c, a, l, s);
1999/0504    
} 
 
void
1999/0504/sys/src/9/alphapc/dma.c:134,140 – 1999/0505/sys/src/9/alphapc/dma.c:134,140
1999/0504    
	dp = &dma[(chan>>2)&1]; 
	chan = chan & 3; 
 
	dmastatus(dp, chan);
1999/0505    
	dmastatus(dp, chan, 'X');
1999/0504    
}
1999/0415    
/*
1999/0504/sys/src/9/alphapc/dma.c:209,215 – 1999/0505/sys/src/9/alphapc/dma.c:209,215
1999/0415    
	outb(dp->count[chan], ((len>>dp->shift)-1)>>8); 
	outb(dp->sbm, chan);		/* enable the channel */ 
	iunlock(dp);
1999/0504    
dmastatus(dp, chan);
1999/0505    
dmastatus(dp, chan, 'S');
1999/0415    
 
	return len; 
}
1999/0504/sys/src/9/alphapc/dma.c:241,247 – 1999/0505/sys/src/9/alphapc/dma.c:241,247
1999/0415    
	dp = &dma[(chan>>2)&1]; 
	chan = chan & 3;
1999/0504    
dmastatus(dp, chan);
1999/0505    
dmastatus(dp, chan, 'E');
1999/0415    
	/* 
	 *  disable the channel 
	 */
1999/0505/sys/src/9/alphapc/dma.c:3,9 – 1999/0506/sys/src/9/alphapc/dma.c:3,8 (short | long)
1999/0415    
#include	"mem.h" 
#include	"dat.h" 
#include	"fns.h" 
#include	"io.h" 
 
typedef struct DMAport	DMAport; 
typedef struct DMA	DMA;
1999/0505/sys/src/9/alphapc/dma.c:63,68 – 1999/0506/sys/src/9/alphapc/dma.c:62,86
1999/0415    
	 1 }, 
};
1999/0506    
static void 
dmastatus(DMA *dp, int chan, char c) 
{ 
	int a, l, s; 
 
	ilock(dp); 
	outb(dp->cbp, 0); 
	a = inb(dp->addr[chan]); 
	a |= inb(dp->addr[chan])<<8; 
	a |= inb(dp->page[chan])<<16; 
	a |= inb(0x400|dp->page[chan])<<24; 
	outb(dp->cbp, 0); 
	l = inb(dp->count[chan]); 
	l |= inb(dp->count[chan])<<8; 
	s = inb(dp->cmd); 
	iunlock(dp); 
	print("%c: addr %uX len %uX stat %uX\n", c, a, l, s); 
}
1999/0415    
/* 
 *  DMA must be in the first 16MB.  This gets called early by the 
 *  initialisation routines of any devices which require DMA to ensure
1999/0505/sys/src/9/alphapc/dma.c:73,79 – 1999/0506/sys/src/9/alphapc/dma.c:91,107
1999/0415    
{ 
	DMA *dp; 
	DMAxfer *xp;
1999/0506    
	static int once;
1999/0415    
1999/0506    
	if(once == 0){ 
		outb(dma[0].mc, 0); 
		outb(dma[1].mc, 0); 
		outb(dma[0].cmask, 0); 
		outb(dma[1].cmask, 0); 
		outb(dma[1].mode, 0xC0); 
		once = 1; 
	}
1999/0423    
	if(maxtransfer > 64*1024) 
		maxtransfer = 64*1024;
1999/0505/sys/src/9/alphapc/dma.c:85,91 – 1999/0506/sys/src/9/alphapc/dma.c:113,119
1999/0423    
			return 1; 
		return 0;
1999/0415    
	}
1999/0501    
outb(dp->mc, 0);
1999/0506    
//dmastatus(dp, chan, 'I');
1999/0423    
 
	xp->bva = xspanalloc(maxtransfer, BY2PG, 64*1024); 
	if(xp->bva == nil)
1999/0505/sys/src/9/alphapc/dma.c:107,131 – 1999/0506/sys/src/9/alphapc/dma.c:135,140
1999/0423    
	return 0;
1999/0415    
}
1999/0504    
static void
1999/0505    
dmastatus(DMA *dp, int chan, char c)
1999/0504    
{ 
	int a, l, s; 
                 
	ilock(dp); 
	outb(dp->cbp, 0); 
	a = inb(dp->addr[chan]); 
	a |= inb(dp->addr[chan])<<8; 
	a |= inb(dp->page[chan])<<16; 
	a |= inb(0x400|dp->page[chan])<<24; 
	outb(dp->cbp, 0); 
	l = inb(dp->count[chan]); 
	l |= inb(dp->count[chan])<<8; 
	s = inb(dp->cmd); 
	iunlock(dp);
1999/0505    
	print("%c: addr %uX len %uX stat %uX\n", c, a, l, s);
1999/0504    
} 
                 
void 
xdmastatus(int chan) 
{
1999/0505/sys/src/9/alphapc/dma.c:159,164 – 1999/0506/sys/src/9/alphapc/dma.c:168,176
1999/0415    
	chan = chan & 3;
1999/0501    
//print("va%lux+", va); 
#define tryPCI
1999/0506    
#ifndef PCIWADDR 
#define PCIWADDR(va)	PADDR(va) 
#endif /* PCIWADDR */
1999/0501    
#ifdef notdef
1999/0415    
	xp = &dp->x[chan];
1999/0505/sys/src/9/alphapc/dma.c:209,215 – 1999/0506/sys/src/9/alphapc/dma.c:221,227
1999/0415    
	outb(dp->count[chan], ((len>>dp->shift)-1)>>8); 
	outb(dp->sbm, chan);		/* enable the channel */ 
	iunlock(dp);
1999/0505    
dmastatus(dp, chan, 'S');
1999/0506    
//dmastatus(dp, chan, 'S');
1999/0415    
 
	return len; 
}
1999/0505/sys/src/9/alphapc/dma.c:241,247 – 1999/0506/sys/src/9/alphapc/dma.c:253,259
1999/0415    
	dp = &dma[(chan>>2)&1]; 
	chan = chan & 3;
1999/0505    
dmastatus(dp, chan, 'E');
1999/0506    
//dmastatus(dp, chan, 'E');
1999/0415    
	/* 
	 *  disable the channel 
	 */
1999/0506/sys/src/9/alphapc/dma.c:4,9 – 1999/0507/sys/src/9/alphapc/dma.c:4,11 (short | long)
1999/0415    
#include	"dat.h" 
#include	"fns.h"
1999/0507    
#include	"io.h"
1999/0415    
typedef struct DMAport	DMAport; 
typedef struct DMA	DMA; 
typedef struct DMAxfer	DMAxfer;
1999/0506/sys/src/9/alphapc/dma.c:166,171 – 1999/0507/sys/src/9/alphapc/dma.c:168,174
1999/0415    
 
	dp = &dma[(chan>>2)&1]; 
	chan = chan & 3;
1999/0507    
	xp = &dp->x[chan];
1999/0501    
//print("va%lux+", va); 
#define tryPCI
1999/0506    
#ifndef PCIWADDR
1999/0506/sys/src/9/alphapc/dma.c:172,178 – 1999/0507/sys/src/9/alphapc/dma.c:175,180
1999/0506    
#define PCIWADDR(va)	PADDR(va) 
#endif /* PCIWADDR */
1999/0501    
#ifdef notdef
1999/0415    
	xp = &dp->x[chan]; 
 
	/* 
	 *  if this isn't kernel memory or crossing 64k boundary or above 16 meg
1999/0506/sys/src/9/alphapc/dma.c:201,206 – 1999/0507/sys/src/9/alphapc/dma.c:203,222
1999/0501    
#endif /* tryISA */ 
#ifdef tryPCI 
	pa = PCIWADDR(va);
1999/0507    
	if((((ulong)va)&0xF0000000) != KZERO){ 
		if(xp->bva == nil) 
			return -1; 
		if(len > xp->blen) 
			len = xp->blen; 
		if(!isread) 
			memmove(xp->bva, va, len); 
		xp->va = va; 
		xp->len = len; 
		xp->isread = isread; 
		pa = PCIWADDR(xp->bva); 
	} 
	else 
		xp->len = 0;
1999/0501    
#endif /* tryPCI */
1999/0415    
 
	/*
1999/0507/sys/src/9/alphapc/dma.c:96,101 – 2000/0401/sys/src/9/alphapc/dma.c:96,105 (short | long)
1999/0506    
	static int once;
1999/0415    
1999/0506    
	if(once == 0){
2000/0401    
		if(ioalloc(0x00, 0x10, 0, "dma") < 0 
		|| ioalloc(0x80, 0x10, 0, "dma") < 0 
		|| ioalloc(0xd0, 0x10, 0, "dma") < 0) 
			panic("dmainit");
1999/0506    
		outb(dma[0].mc, 0); 
		outb(dma[1].mc, 0); 
		outb(dma[0].cmask, 0);
2000/0401/sys/src/9/alphapc/dma.c:119,125 – 2001/1208/sys/src/9/alphapc/dma.c:119,125 (short | long)
1999/0423    
			return 1; 
		return 0;
1999/0415    
	}
1999/0506    
//dmastatus(dp, chan, 'I');
2001/1208    
dmastatus(dp, chan, 'I');
1999/0423    
 
	xp->bva = xspanalloc(maxtransfer, BY2PG, 64*1024); 
	if(xp->bva == nil)
2000/0401/sys/src/9/alphapc/dma.c:241,247 – 2001/1208/sys/src/9/alphapc/dma.c:241,247
1999/0415    
	outb(dp->count[chan], ((len>>dp->shift)-1)>>8); 
	outb(dp->sbm, chan);		/* enable the channel */ 
	iunlock(dp);
1999/0506    
//dmastatus(dp, chan, 'S');
2001/1208    
dmastatus(dp, chan, 'S');
1999/0415    
 
	return len; 
}
2000/0401/sys/src/9/alphapc/dma.c:273,279 – 2001/1208/sys/src/9/alphapc/dma.c:273,279
1999/0415    
	dp = &dma[(chan>>2)&1]; 
	chan = chan & 3;
1999/0506    
//dmastatus(dp, chan, 'E');
2001/1208    
dmastatus(dp, chan, 'E');
1999/0415    
	/* 
	 *  disable the channel 
	 */
2001/1208/sys/src/9/alphapc/dma.c:119,125 – 2001/1210/sys/src/9/alphapc/dma.c:119,125 (short | long)
1999/0423    
			return 1; 
		return 0;
1999/0415    
	}
2001/1208    
dmastatus(dp, chan, 'I');
2001/1210    
//dmastatus(dp, chan, 'I');
1999/0423    
 
	xp->bva = xspanalloc(maxtransfer, BY2PG, 64*1024); 
	if(xp->bva == nil)
2001/1208/sys/src/9/alphapc/dma.c:241,247 – 2001/1210/sys/src/9/alphapc/dma.c:241,247
1999/0415    
	outb(dp->count[chan], ((len>>dp->shift)-1)>>8); 
	outb(dp->sbm, chan);		/* enable the channel */ 
	iunlock(dp);
2001/1208    
dmastatus(dp, chan, 'S');
2001/1210    
//dmastatus(dp, chan, 'S');
1999/0415    
 
	return len; 
}
2001/1208/sys/src/9/alphapc/dma.c:273,279 – 2001/1210/sys/src/9/alphapc/dma.c:273,279
1999/0415    
	dp = &dma[(chan>>2)&1]; 
	chan = chan & 3;
2001/1208    
dmastatus(dp, chan, 'E');
2001/1210    
//dmastatus(dp, chan, 'E');
1999/0415    
	/* 
	 *  disable the channel 
	 */


source code copyright © 1990-2005 Lucent Technologies; see license
Plan 9 distribution
comments to russ cox (rsc@swtch.com)