NetBSD/sys/arch/atari/isa/isa_dma.c

694 lines
18 KiB
C

/* $NetBSD: isa_dma.c,v 1.1 2001/03/09 20:55:47 leo Exp $ */
#define ISA_DMA_STATS
/*-
* Copyright (c) 1996, 1997, 1998 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Charles M. Hannum and by Jason R. Thorpe of the Numerical Aerospace
* Simulation Facility, NASA Ames Research Center.
*
* 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 the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``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 FOUNDATION OR CONTRIBUTORS
* 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/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/syslog.h>
#include <sys/device.h>
#include <sys/malloc.h>
#include <sys/proc.h>
#include <sys/mbuf.h>
#define _ATARI_BUS_DMA_PRIVATE
#include <machine/bus.h>
#include <dev/isa/isareg.h>
#include <dev/isa/isavar.h>
#include <uvm/uvm_extern.h>
/*
* ISA can only DMA to 0-16M.
*/
#define ISA_DMA_BOUNCE_THRESHOLD (16 * 1024 * 1024)
extern paddr_t avail_end;
/*
* Cookie used by ISA dma. A pointer to one of these it stashed in
* the DMA map.
*/
struct atari_isa_dma_cookie {
int id_flags; /* flags; see below */
/*
* Information about the original buffer used during
* DMA map syncs. Note that origibuflen is only used
* for ID_BUFTYPE_LINEAR.
*/
void *id_origbuf; /* pointer to orig buffer if
bouncing */
bus_size_t id_origbuflen; /* ...and size */
int id_buftype; /* type of buffer */
void *id_bouncebuf; /* pointer to the bounce buffer */
bus_size_t id_bouncebuflen; /* ...and size */
int id_nbouncesegs; /* number of valid bounce segs */
bus_dma_segment_t id_bouncesegs[0]; /* array of bounce buffer
physical memory segments */
};
/* id_flags */
#define ID_MIGHT_NEED_BOUNCE 0x01 /* map could need bounce buffers */
#define ID_HAS_BOUNCE 0x02 /* map currently has bounce buffers */
#define ID_IS_BOUNCING 0x04 /* map is bouncing current xfer */
/* id_buftype */
#define ID_BUFTYPE_INVALID 0
#define ID_BUFTYPE_LINEAR 1
#define ID_BUFTYPE_MBUF 2
#define ID_BUFTYPE_UIO 3
#define ID_BUFTYPE_RAW 4
int _isa_bus_dmamap_create __P((bus_dma_tag_t, bus_size_t, int,
bus_size_t, bus_size_t, int, bus_dmamap_t *));
void _isa_bus_dmamap_destroy __P((bus_dma_tag_t, bus_dmamap_t));
int _isa_bus_dmamap_load __P((bus_dma_tag_t, bus_dmamap_t, void *,
bus_size_t, struct proc *, int));
int _isa_bus_dmamap_load_mbuf __P((bus_dma_tag_t, bus_dmamap_t,
struct mbuf *, int));
int _isa_bus_dmamap_load_uio __P((bus_dma_tag_t, bus_dmamap_t,
struct uio *, int));
int _isa_bus_dmamap_load_raw __P((bus_dma_tag_t, bus_dmamap_t,
bus_dma_segment_t *, int, bus_size_t, int));
void _isa_bus_dmamap_unload __P((bus_dma_tag_t, bus_dmamap_t));
void _isa_bus_dmamap_sync __P((bus_dma_tag_t, bus_dmamap_t,
bus_addr_t, bus_size_t, int));
int _isa_bus_dmamem_alloc __P((bus_dma_tag_t, bus_size_t, bus_size_t,
bus_size_t, bus_dma_segment_t *, int, int *, int));
int _isa_dma_alloc_bouncebuf __P((bus_dma_tag_t, bus_dmamap_t,
bus_size_t, int));
void _isa_dma_free_bouncebuf __P((bus_dma_tag_t, bus_dmamap_t));
/*
* Entry points for ISA DMA. These are mostly wrappers around
* the generic functions that understand how to deal with bounce
* buffers, if necessary.
*/
struct atari_bus_dma_tag isa_bus_dma_tag = {
ISA_DMA_BOUNCE_THRESHOLD,
0,
_isa_bus_dmamap_create,
_isa_bus_dmamap_destroy,
_isa_bus_dmamap_load,
_isa_bus_dmamap_load_mbuf,
_isa_bus_dmamap_load_uio,
_isa_bus_dmamap_load_raw,
_isa_bus_dmamap_unload,
_isa_bus_dmamap_sync,
};
/**********************************************************************
* bus.h dma interface entry points
**********************************************************************/
#ifdef ISA_DMA_STATS
#define STAT_INCR(v) (v)++
#define STAT_DECR(v) do { \
if ((v) == 0) \
printf("%s:%d -- Already 0!\n", __FILE__, __LINE__); \
else \
(v)--; \
} while (0)
u_long isa_dma_stats_loads;
u_long isa_dma_stats_bounces;
u_long isa_dma_stats_nbouncebufs;
#else
#define STAT_INCR(v)
#define STAT_DECR(v)
#endif
/*
* Create an ISA DMA map.
*/
int
_isa_bus_dmamap_create(t, size, nsegments, maxsegsz, boundary, flags, dmamp)
bus_dma_tag_t t;
bus_size_t size;
int nsegments;
bus_size_t maxsegsz;
bus_size_t boundary;
int flags;
bus_dmamap_t *dmamp;
{
struct atari_isa_dma_cookie *cookie;
bus_dmamap_t map;
int error, cookieflags;
void *cookiestore;
size_t cookiesize;
/* Call common function to create the basic map. */
error = _bus_dmamap_create(t, size, nsegments, maxsegsz, boundary,
flags, dmamp);
if (error)
return (error);
map = *dmamp;
map->_dm_cookie = NULL;
cookiesize = sizeof(struct atari_isa_dma_cookie);
/*
* ISA only has 24-bits of address space. This means
* we can't DMA to pages over 16M. In order to DMA to
* arbitrary buffers, we use "bounce buffers" - pages
* in memory below the 16M boundary. On DMA reads,
* DMA happens to the bounce buffers, and is copied into
* the caller's buffer. On writes, data is copied into
* but bounce buffer, and the DMA happens from those
* pages. To software using the DMA mapping interface,
* this looks simply like a data cache.
*
* If we have more than 16M of RAM in the system, we may
* need bounce buffers. We check and remember that here.
*
* There are exceptions, however. VLB devices can do
* 32-bit DMA, and indicate that here.
*
* ...or, there is an opposite case. The most segments
* a transfer will require is (maxxfer / PAGE_SIZE) + 1. If
* the caller can't handle that many segments (e.g. the
* ISA DMA controller), we may have to bounce it as well.
*/
if (avail_end <= t->_bounce_thresh ||
(flags & ISABUS_DMA_32BIT) != 0) {
/* Bouncing not necessary due to memory size. */
map->_dm_bounce_thresh = 0;
}
cookieflags = 0;
if (map->_dm_bounce_thresh != 0 ||
((map->_dm_size / PAGE_SIZE) + 1) > map->_dm_segcnt) {
cookieflags |= ID_MIGHT_NEED_BOUNCE;
cookiesize += (sizeof(bus_dma_segment_t) * map->_dm_segcnt);
}
/*
* Allocate our cookie.
*/
if ((cookiestore = malloc(cookiesize, M_DMAMAP,
(flags & BUS_DMA_NOWAIT) ? M_NOWAIT : M_WAITOK)) == NULL) {
error = ENOMEM;
goto out;
}
memset(cookiestore, 0, cookiesize);
cookie = (struct atari_isa_dma_cookie *)cookiestore;
cookie->id_flags = cookieflags;
map->_dm_cookie = cookie;
if (cookieflags & ID_MIGHT_NEED_BOUNCE) {
/*
* Allocate the bounce pages now if the caller
* wishes us to do so.
*/
if ((flags & BUS_DMA_ALLOCNOW) == 0)
goto out;
error = _isa_dma_alloc_bouncebuf(t, map, size, flags);
}
out:
if (error) {
if (map->_dm_cookie != NULL)
free(map->_dm_cookie, M_DMAMAP);
_bus_dmamap_destroy(t, map);
}
return (error);
}
/*
* Destroy an ISA DMA map.
*/
void
_isa_bus_dmamap_destroy(t, map)
bus_dma_tag_t t;
bus_dmamap_t map;
{
struct atari_isa_dma_cookie *cookie = map->_dm_cookie;
/*
* Free any bounce pages this map might hold.
*/
if (cookie->id_flags & ID_HAS_BOUNCE)
_isa_dma_free_bouncebuf(t, map);
free(cookie, M_DMAMAP);
_bus_dmamap_destroy(t, map);
}
/*
* Load an ISA DMA map with a linear buffer.
*/
int
_isa_bus_dmamap_load(t, map, buf, buflen, p, flags)
bus_dma_tag_t t;
bus_dmamap_t map;
void *buf;
bus_size_t buflen;
struct proc *p;
int flags;
{
struct atari_isa_dma_cookie *cookie = map->_dm_cookie;
int error;
STAT_INCR(isa_dma_stats_loads);
/*
* Make sure that on error condition we return "no valid mappings."
*/
map->dm_mapsize = 0;
map->dm_nsegs = 0;
/*
* Try to load the map the normal way. If this errors out,
* and we can bounce, we will.
*/
error = _bus_dmamap_load(t, map, buf, buflen, p, flags);
if (error == 0 ||
(error != 0 && (cookie->id_flags & ID_MIGHT_NEED_BOUNCE) == 0))
return (error);
/*
* First attempt failed; bounce it.
*/
STAT_INCR(isa_dma_stats_bounces);
/*
* Allocate bounce pages, if necessary.
*/
if ((cookie->id_flags & ID_HAS_BOUNCE) == 0) {
error = _isa_dma_alloc_bouncebuf(t, map, buflen, flags);
if (error)
return (error);
}
/*
* Cache a pointer to the caller's buffer and load the DMA map
* with the bounce buffer.
*/
cookie->id_origbuf = buf;
cookie->id_origbuflen = buflen;
cookie->id_buftype = ID_BUFTYPE_LINEAR;
error = _bus_dmamap_load(t, map, cookie->id_bouncebuf, buflen,
p, flags);
if (error) {
/*
* Free the bounce pages, unless our resources
* are reserved for our exclusive use.
*/
if ((map->_dm_flags & BUS_DMA_ALLOCNOW) == 0)
_isa_dma_free_bouncebuf(t, map);
return (error);
}
/* ...so _isa_bus_dmamap_sync() knows we're bouncing */
cookie->id_flags |= ID_IS_BOUNCING;
return (0);
}
/*
* Like _isa_bus_dmamap_load(), but for mbufs.
*/
int
_isa_bus_dmamap_load_mbuf(t, map, m0, flags)
bus_dma_tag_t t;
bus_dmamap_t map;
struct mbuf *m0;
int flags;
{
struct atari_isa_dma_cookie *cookie = map->_dm_cookie;
int error;
/*
* Make sure on error condition we return "no valid mappings."
*/
map->dm_mapsize = 0;
map->dm_nsegs = 0;
#ifdef DIAGNOSTIC
if ((m0->m_flags & M_PKTHDR) == 0)
panic("_isa_bus_dmamap_load_mbuf: no packet header");
#endif
if (m0->m_pkthdr.len > map->_dm_size)
return (EINVAL);
/*
* Try to load the map the normal way. If this errors out,
* and we can bounce, we will.
*/
error = _bus_dmamap_load_mbuf(t, map, m0, flags);
if (error == 0 ||
(error != 0 && (cookie->id_flags & ID_MIGHT_NEED_BOUNCE) == 0))
return (error);
/*
* First attempt failed; bounce it.
*/
STAT_INCR(isa_dma_stats_bounces);
/*
* Allocate bounce pages, if necessary.
*/
if ((cookie->id_flags & ID_HAS_BOUNCE) == 0) {
error = _isa_dma_alloc_bouncebuf(t, map, m0->m_pkthdr.len,
flags);
if (error)
return (error);
}
/*
* Cache a pointer to the caller's buffer and load the DMA map
* with the bounce buffer.
*/
cookie->id_origbuf = m0;
cookie->id_origbuflen = m0->m_pkthdr.len; /* not really used */
cookie->id_buftype = ID_BUFTYPE_MBUF;
error = _bus_dmamap_load(t, map, cookie->id_bouncebuf,
m0->m_pkthdr.len, NULL, flags);
if (error) {
/*
* Free the bounce pages, unless our resources
* are reserved for our exclusive use.
*/
if ((map->_dm_flags & BUS_DMA_ALLOCNOW) == 0)
_isa_dma_free_bouncebuf(t, map);
return (error);
}
/* ...so _isa_bus_dmamap_sync() knows we're bouncing */
cookie->id_flags |= ID_IS_BOUNCING;
return (0);
}
/*
* Like _isa_bus_dmamap_load(), but for uios.
*/
int
_isa_bus_dmamap_load_uio(t, map, uio, flags)
bus_dma_tag_t t;
bus_dmamap_t map;
struct uio *uio;
int flags;
{
panic("_isa_bus_dmamap_load_uio: not implemented");
}
/*
* Like _isa_bus_dmamap_load(), but for raw memory allocated with
* bus_dmamem_alloc().
*/
int
_isa_bus_dmamap_load_raw(t, map, segs, nsegs, size, flags)
bus_dma_tag_t t;
bus_dmamap_t map;
bus_dma_segment_t *segs;
int nsegs;
bus_size_t size;
int flags;
{
panic("_isa_bus_dmamap_load_raw: not implemented");
}
/*
* Unload an ISA DMA map.
*/
void
_isa_bus_dmamap_unload(t, map)
bus_dma_tag_t t;
bus_dmamap_t map;
{
struct atari_isa_dma_cookie *cookie = map->_dm_cookie;
/*
* If we have bounce pages, free them, unless they're
* reserved for our exclusive use.
*/
if ((cookie->id_flags & ID_HAS_BOUNCE) &&
(map->_dm_flags & BUS_DMA_ALLOCNOW) == 0)
_isa_dma_free_bouncebuf(t, map);
cookie->id_flags &= ~ID_IS_BOUNCING;
cookie->id_buftype = ID_BUFTYPE_INVALID;
/*
* Do the generic bits of the unload.
*/
_bus_dmamap_unload(t, map);
}
/*
* Synchronize an ISA DMA map.
*/
void
_isa_bus_dmamap_sync(t, map, offset, len, ops)
bus_dma_tag_t t;
bus_dmamap_t map;
bus_addr_t offset;
bus_size_t len;
int ops;
{
struct atari_isa_dma_cookie *cookie = map->_dm_cookie;
/*
* Mixing PRE and POST operations is not allowed.
*/
if ((ops & (BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE)) != 0 &&
(ops & (BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE)) != 0)
panic("_isa_bus_dmamap_sync: mix PRE and POST");
#ifdef DIAGNOSTIC
if ((ops & (BUS_DMASYNC_PREWRITE|BUS_DMASYNC_POSTREAD)) != 0) {
if (offset >= map->dm_mapsize)
panic("_isa_bus_dmamap_sync: bad offset");
if (len == 0 || (offset + len) > map->dm_mapsize)
panic("_isa_bus_dmamap_sync: bad length");
}
#endif
/*
* If we're not bouncing, just return; nothing to do.
*/
if ((cookie->id_flags & ID_IS_BOUNCING) == 0)
return;
switch (cookie->id_buftype) {
case ID_BUFTYPE_LINEAR:
/*
* Nothing to do for pre-read.
*/
if (ops & BUS_DMASYNC_PREWRITE) {
/*
* Copy the caller's buffer to the bounce buffer.
*/
memcpy((char *)cookie->id_bouncebuf + offset,
(char *)cookie->id_origbuf + offset, len);
}
if (ops & BUS_DMASYNC_POSTREAD) {
/*
* Copy the bounce buffer to the caller's buffer.
*/
memcpy((char *)cookie->id_origbuf + offset,
(char *)cookie->id_bouncebuf + offset, len);
}
/*
* Nothing to do for post-write.
*/
break;
case ID_BUFTYPE_MBUF:
{
struct mbuf *m, *m0 = cookie->id_origbuf;
bus_size_t minlen, moff;
/*
* Nothing to do for pre-read.
*/
if (ops & BUS_DMASYNC_PREWRITE) {
/*
* Copy the caller's buffer to the bounce buffer.
*/
m_copydata(m0, offset, len,
(char *)cookie->id_bouncebuf + offset);
}
if (ops & BUS_DMASYNC_POSTREAD) {
/*
* Copy the bounce buffer to the caller's buffer.
*/
for (moff = offset, m = m0; m != NULL && len != 0;
m = m->m_next) {
/* Find the beginning mbuf. */
if (moff >= m->m_len) {
moff -= m->m_len;
continue;
}
/*
* Now at the first mbuf to sync; nail
* each one until we have exhausted the
* length.
*/
minlen = len < m->m_len - moff ?
len : m->m_len - moff;
memcpy(mtod(m, caddr_t) + moff,
(char *)cookie->id_bouncebuf + offset,
minlen);
moff = 0;
len -= minlen;
offset += minlen;
}
}
/*
* Nothing to do for post-write.
*/
break;
}
case ID_BUFTYPE_UIO:
panic("_isa_bus_dmamap_sync: ID_BUFTYPE_UIO");
break;
case ID_BUFTYPE_RAW:
panic("_isa_bus_dmamap_sync: ID_BUFTYPE_RAW");
break;
case ID_BUFTYPE_INVALID:
panic("_isa_bus_dmamap_sync: ID_BUFTYPE_INVALID");
break;
default:
printf("unknown buffer type %d\n", cookie->id_buftype);
panic("_isa_bus_dmamap_sync");
}
}
/*
* Allocate memory safe for ISA DMA.
*/
int
_isa_bus_dmamem_alloc(t, size, alignment, boundary, segs, nsegs, rsegs, flags)
bus_dma_tag_t t;
bus_size_t size, alignment, boundary;
bus_dma_segment_t *segs;
int nsegs;
int *rsegs;
int flags;
{
paddr_t high;
if (avail_end > ISA_DMA_BOUNCE_THRESHOLD)
high = trunc_page(ISA_DMA_BOUNCE_THRESHOLD);
else
high = trunc_page(avail_end);
return (bus_dmamem_alloc_range(t, size, alignment, boundary,
segs, nsegs, rsegs, flags, 0, high));
}
/**********************************************************************
* ISA DMA utility functions
**********************************************************************/
int
_isa_dma_alloc_bouncebuf(t, map, size, flags)
bus_dma_tag_t t;
bus_dmamap_t map;
bus_size_t size;
int flags;
{
struct atari_isa_dma_cookie *cookie = map->_dm_cookie;
int error = 0;
cookie->id_bouncebuflen = round_page(size);
error = _isa_bus_dmamem_alloc(t, cookie->id_bouncebuflen,
PAGE_SIZE, map->_dm_boundary, cookie->id_bouncesegs,
map->_dm_segcnt, &cookie->id_nbouncesegs, flags);
if (error)
goto out;
error = bus_dmamem_map(t, cookie->id_bouncesegs,
cookie->id_nbouncesegs, cookie->id_bouncebuflen,
(caddr_t *)&cookie->id_bouncebuf, flags);
out:
if (error) {
bus_dmamem_free(t, cookie->id_bouncesegs,
cookie->id_nbouncesegs);
cookie->id_bouncebuflen = 0;
cookie->id_nbouncesegs = 0;
} else {
cookie->id_flags |= ID_HAS_BOUNCE;
STAT_INCR(isa_dma_stats_nbouncebufs);
}
return (error);
}
void
_isa_dma_free_bouncebuf(t, map)
bus_dma_tag_t t;
bus_dmamap_t map;
{
struct atari_isa_dma_cookie *cookie = map->_dm_cookie;
STAT_DECR(isa_dma_stats_nbouncebufs);
bus_dmamem_unmap(t, cookie->id_bouncebuf,
cookie->id_bouncebuflen);
bus_dmamem_free(t, cookie->id_bouncesegs,
cookie->id_nbouncesegs);
cookie->id_bouncebuflen = 0;
cookie->id_nbouncesegs = 0;
cookie->id_flags &= ~ID_HAS_BOUNCE;
}