NetBSD-5.0.2/sys/arch/x86/x86/bus_dma.c
/* $NetBSD: bus_dma.c,v 1.45 2008/06/28 17:23:01 bouyer Exp $ */
/*-
* Copyright (c) 1996, 1997, 1998, 2007 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, and by Andrew Doran.
*
* 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.
*
* 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/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: bus_dma.c,v 1.45 2008/06/28 17:23:01 bouyer Exp $");
/*
* The following is included because _bus_dma_uiomove is derived from
* uiomove() in kern_subr.c.
*/
/*
* Copyright (c) 1982, 1986, 1991, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Copyright (c) 1992, 1993
* The Regents of the University of California. All rights reserved.
*
* This software was developed by the Computer Systems Engineering group
* at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
* contributed to Berkeley.
*
* All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Lawrence Berkeley Laboratory.
*
* 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. Neither the name of the University 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 REGENTS 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 REGENTS 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 "ioapic.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/proc.h>
#include <machine/bus.h>
#include <machine/bus_private.h>
#include <machine/i82093var.h>
#include <machine/mpbiosvar.h>
#include <dev/isa/isareg.h>
#include <dev/isa/isavar.h>
#include <uvm/uvm_extern.h>
extern paddr_t avail_end;
#define IDTVEC(name) __CONCAT(X,name)
typedef void (vector) __P((void));
extern vector *IDTVEC(intr)[];
#define BUSDMA_BOUNCESTATS
#ifdef BUSDMA_BOUNCESTATS
#define BUSDMA_EVCNT_DECL(name) \
static struct evcnt bus_dma_ev_##name = \
EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, "bus_dma", #name); \
EVCNT_ATTACH_STATIC(bus_dma_ev_##name)
#define STAT_INCR(name) \
bus_dma_ev_##name.ev_count++
#define STAT_DECR(name) \
bus_dma_ev_##name.ev_count--
BUSDMA_EVCNT_DECL(nbouncebufs);
BUSDMA_EVCNT_DECL(loads);
BUSDMA_EVCNT_DECL(bounces);
#else
#define STAT_INCR(x)
#define STAT_DECR(x)
#endif
static int _bus_dma_uiomove(void *, struct uio *, size_t, int);
static int _bus_dma_alloc_bouncebuf(bus_dma_tag_t t, bus_dmamap_t map,
bus_size_t size, int flags);
static void _bus_dma_free_bouncebuf(bus_dma_tag_t t, bus_dmamap_t map);
static int _bus_dmamap_load_buffer(bus_dma_tag_t t, bus_dmamap_t map,
void *buf, bus_size_t buflen, struct vmspace *vm, int flags);
static inline int _bus_dmamap_load_busaddr(bus_dma_tag_t, bus_dmamap_t,
bus_addr_t, int);
#ifndef _BUS_DMAMEM_ALLOC_RANGE
#define _BUS_DMAMEM_ALLOC_RANGE _bus_dmamem_alloc_range
/*
* Allocate physical memory from the given physical address range.
* Called by DMA-safe memory allocation methods.
*/
int
_bus_dmamem_alloc_range(bus_dma_tag_t t, bus_size_t size,
bus_size_t alignment, bus_size_t boundary, bus_dma_segment_t *segs,
int nsegs, int *rsegs, int flags, bus_addr_t low, bus_addr_t high)
{
paddr_t curaddr, lastaddr;
struct vm_page *m;
struct pglist mlist;
int curseg, error;
/* Always round the size. */
size = round_page(size);
/*
* Allocate pages from the VM system.
*/
error = uvm_pglistalloc(size, low, high, alignment, boundary,
&mlist, nsegs, (flags & BUS_DMA_NOWAIT) == 0);
if (error)
return (error);
/*
* Compute the location, size, and number of segments actually
* returned by the VM code.
*/
m = TAILQ_FIRST(&mlist);
curseg = 0;
lastaddr = segs[curseg].ds_addr = VM_PAGE_TO_PHYS(m);
segs[curseg].ds_len = PAGE_SIZE;
m = m->pageq.queue.tqe_next;
for (; m != NULL; m = m->pageq.queue.tqe_next) {
curaddr = VM_PAGE_TO_PHYS(m);
#ifdef DIAGNOSTIC
if (curaddr < low || curaddr >= high) {
printf("vm_page_alloc_memory returned non-sensical"
" address 0x%lx\n", curaddr);
panic("_bus_dmamem_alloc_range");
}
#endif
if (curaddr == (lastaddr + PAGE_SIZE))
segs[curseg].ds_len += PAGE_SIZE;
else {
curseg++;
segs[curseg].ds_addr = curaddr;
segs[curseg].ds_len = PAGE_SIZE;
}
lastaddr = curaddr;
}
*rsegs = curseg + 1;
return (0);
}
#endif /* _BUS_DMAMEM_ALLOC_RANGE */
/*
* Create a DMA map.
*/
int
_bus_dmamap_create(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 x86_bus_dma_cookie *cookie;
bus_dmamap_t map;
int error, cookieflags;
void *cookiestore, *mapstore;
size_t cookiesize, mapsize;
/*
* Allocate and initialize the DMA map. The end of the map
* is a variable-sized array of segments, so we allocate enough
* room for them in one shot.
*
* Note we don't preserve the WAITOK or NOWAIT flags. Preservation
* of ALLOCNOW notifies others that we've reserved these resources,
* and they are not to be freed.
*
* The bus_dmamap_t includes one bus_dma_segment_t, hence
* the (nsegments - 1).
*/
error = 0;
mapsize = sizeof(struct x86_bus_dmamap) +
(sizeof(bus_dma_segment_t) * (nsegments - 1));
if ((mapstore = malloc(mapsize, M_DMAMAP,
(flags & BUS_DMA_NOWAIT) ? M_NOWAIT : M_WAITOK)) == NULL)
return (ENOMEM);
memset(mapstore, 0, mapsize);
map = (struct x86_bus_dmamap *)mapstore;
map->_dm_size = size;
map->_dm_segcnt = nsegments;
map->_dm_maxmaxsegsz = maxsegsz;
map->_dm_boundary = boundary;
map->_dm_bounce_thresh = t->_bounce_thresh;
map->_dm_flags = flags & ~(BUS_DMA_WAITOK|BUS_DMA_NOWAIT);
map->dm_maxsegsz = maxsegsz;
map->dm_mapsize = 0; /* no valid mappings */
map->dm_nsegs = 0;
*dmamp = map;
if (t->_bounce_thresh == 0 || _BUS_AVAIL_END <= t->_bounce_thresh)
map->_dm_bounce_thresh = 0;
cookieflags = 0;
if (t->_may_bounce != NULL) {
error = t->_may_bounce(t, map, flags, &cookieflags);
if (error != 0)
goto out;
}
if (map->_dm_bounce_thresh != 0)
cookieflags |= X86_DMA_MIGHT_NEED_BOUNCE;
if ((cookieflags & X86_DMA_MIGHT_NEED_BOUNCE) == 0)
return 0;
cookiesize = sizeof(struct x86_bus_dma_cookie) +
(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 x86_bus_dma_cookie *)cookiestore;
cookie->id_flags = cookieflags;
map->_dm_cookie = cookie;
error = _bus_dma_alloc_bouncebuf(t, map, size, flags);
out:
if (error)
_bus_dmamap_destroy(t, map);
return (error);
}
/*
* Destroy a DMA map.
*/
void
_bus_dmamap_destroy(bus_dma_tag_t t, bus_dmamap_t map)
{
struct x86_bus_dma_cookie *cookie = map->_dm_cookie;
/*
* Free any bounce pages this map might hold.
*/
if (cookie != NULL) {
if (cookie->id_flags & X86_DMA_HAS_BOUNCE)
_bus_dma_free_bouncebuf(t, map);
free(cookie, M_DMAMAP);
}
free(map, M_DMAMAP);
}
/*
* Load a DMA map with a linear buffer.
*/
int
_bus_dmamap_load(bus_dma_tag_t t, bus_dmamap_t map, void *buf,
bus_size_t buflen, struct proc *p, int flags)
{
struct x86_bus_dma_cookie *cookie = map->_dm_cookie;
int error;
struct vmspace *vm;
STAT_INCR(loads);
/*
* Make sure that on error condition we return "no valid mappings."
*/
map->dm_mapsize = 0;
map->dm_nsegs = 0;
KASSERT(map->dm_maxsegsz <= map->_dm_maxmaxsegsz);
if (buflen > map->_dm_size)
return EINVAL;
if (p != NULL) {
vm = p->p_vmspace;
} else {
vm = vmspace_kernel();
}
error = _bus_dmamap_load_buffer(t, map, buf, buflen, vm, flags);
if (error == 0) {
map->dm_mapsize = buflen;
return 0;
}
if (cookie == NULL)
return error;
if ((cookie->id_flags & X86_DMA_MIGHT_NEED_BOUNCE) == 0)
return error;
/*
* First attempt failed; bounce it.
*/
STAT_INCR(bounces);
/*
* Allocate bounce pages, if necessary.
*/
if ((cookie->id_flags & X86_DMA_HAS_BOUNCE) == 0) {
error = _bus_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 = X86_DMA_BUFTYPE_LINEAR;
map->dm_nsegs = 0;
error = _bus_dmamap_load(t, map, cookie->id_bouncebuf, buflen,
p, flags);
if (error)
return (error);
/* ...so _bus_dmamap_sync() knows we're bouncing */
cookie->id_flags |= X86_DMA_IS_BOUNCING;
return (0);
}
static inline int
_bus_dmamap_load_busaddr(bus_dma_tag_t t, bus_dmamap_t map,
bus_addr_t addr, int size)
{
bus_dma_segment_t * const segs = map->dm_segs;
int nseg = map->dm_nsegs;
bus_addr_t bmask = ~(map->_dm_boundary - 1);
bus_addr_t lastaddr = 0xdead; /* XXX gcc */
int sgsize;
int error = 0;
if (nseg > 0)
lastaddr = segs[nseg-1].ds_addr + segs[nseg-1].ds_len;
again:
sgsize = size;
/*
* Make sure we don't cross any boundaries.
*/
if (map->_dm_boundary > 0) {
bus_addr_t baddr; /* next boundary address */
baddr = (addr + map->_dm_boundary) & bmask;
if (sgsize > (baddr - addr))
sgsize = (baddr - addr);
}
/*
* Insert chunk into a segment, coalescing with
* previous segment if possible.
*/
if (nseg > 0 && addr == lastaddr &&
segs[nseg-1].ds_len + sgsize <= map->dm_maxsegsz &&
(map->_dm_boundary == 0 ||
(segs[nseg-1].ds_addr & bmask) == (addr & bmask))) {
/* coalesce */
segs[nseg-1].ds_len += sgsize;
} else if (nseg >= map->_dm_segcnt) {
return EFBIG;
} else {
/* new segment */
segs[nseg].ds_addr = addr;
segs[nseg].ds_len = sgsize;
nseg++;
}
lastaddr = addr + sgsize;
if (map->_dm_bounce_thresh != 0 && lastaddr > map->_dm_bounce_thresh)
return EINVAL;
addr += sgsize;
size -= sgsize;
if (size > 0)
goto again;
map->dm_nsegs = nseg;
return error;
}
/*
* Like _bus_dmamap_load(), but for mbufs.
*/
int
_bus_dmamap_load_mbuf(bus_dma_tag_t t, bus_dmamap_t map, struct mbuf *m0,
int flags)
{
struct x86_bus_dma_cookie *cookie = map->_dm_cookie;
int error;
struct mbuf *m;
/*
* Make sure on error condition we return "no valid mappings."
*/
map->dm_mapsize = 0;
map->dm_nsegs = 0;
KASSERT(map->dm_maxsegsz <= map->_dm_maxmaxsegsz);
#ifdef DIAGNOSTIC
if ((m0->m_flags & M_PKTHDR) == 0)
panic("_bus_dmamap_load_mbuf: no packet header");
#endif
if (m0->m_pkthdr.len > map->_dm_size)
return (EINVAL);
error = 0;
for (m = m0; m != NULL && error == 0; m = m->m_next) {
int offset;
int remainbytes;
const struct vm_page * const *pgs;
paddr_t paddr;
int size;
if (m->m_len == 0)
continue;
switch (m->m_flags & (M_EXT|M_EXT_CLUSTER|M_EXT_PAGES)) {
case M_EXT|M_EXT_CLUSTER:
/* XXX KDASSERT */
KASSERT(m->m_ext.ext_paddr != M_PADDR_INVALID);
paddr = m->m_ext.ext_paddr +
(m->m_data - m->m_ext.ext_buf);
size = m->m_len;
error = _bus_dmamap_load_busaddr(t, map,
_BUS_PHYS_TO_BUS(paddr), size);
break;
case M_EXT|M_EXT_PAGES:
KASSERT(m->m_ext.ext_buf <= m->m_data);
KASSERT(m->m_data <=
m->m_ext.ext_buf + m->m_ext.ext_size);
offset = (vaddr_t)m->m_data -
trunc_page((vaddr_t)m->m_ext.ext_buf);
remainbytes = m->m_len;
/* skip uninteresting pages */
pgs = (const struct vm_page * const *)
m->m_ext.ext_pgs + (offset >> PAGE_SHIFT);
offset &= PAGE_MASK; /* offset in the first page */
/* load each pages */
while (remainbytes > 0) {
const struct vm_page *pg;
bus_addr_t busaddr;
size = MIN(remainbytes, PAGE_SIZE - offset);
pg = *pgs++;
KASSERT(pg);
busaddr = _BUS_VM_PAGE_TO_BUS(pg) + offset;
error = _bus_dmamap_load_busaddr(t, map,
busaddr, size);
if (error)
break;
offset = 0;
remainbytes -= size;
}
break;
case 0:
paddr = m->m_paddr + M_BUFOFFSET(m) +
(m->m_data - M_BUFADDR(m));
size = m->m_len;
error = _bus_dmamap_load_busaddr(t, map,
_BUS_PHYS_TO_BUS(paddr), size);
break;
default:
error = _bus_dmamap_load_buffer(t, map, m->m_data,
m->m_len, vmspace_kernel(), flags);
}
}
if (error == 0) {
map->dm_mapsize = m0->m_pkthdr.len;
return 0;
}
map->dm_nsegs = 0;
if (cookie == NULL ||
((cookie->id_flags & X86_DMA_MIGHT_NEED_BOUNCE) == 0))
return error;
/*
* First attempt failed; bounce it.
*/
STAT_INCR(bounces);
/*
* Allocate bounce pages, if necessary.
*/
if ((cookie->id_flags & X86_DMA_HAS_BOUNCE) == 0) {
error = _bus_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 = X86_DMA_BUFTYPE_MBUF;
error = _bus_dmamap_load(t, map, cookie->id_bouncebuf,
m0->m_pkthdr.len, NULL, flags);
if (error)
return (error);
/* ...so _bus_dmamap_sync() knows we're bouncing */
cookie->id_flags |= X86_DMA_IS_BOUNCING;
return (0);
}
/*
* Like _bus_dmamap_load(), but for uios.
*/
int
_bus_dmamap_load_uio(bus_dma_tag_t t, bus_dmamap_t map, struct uio *uio,
int flags)
{
int i, error;
bus_size_t minlen, resid;
struct vmspace *vm;
struct iovec *iov;
void *addr;
struct x86_bus_dma_cookie *cookie = map->_dm_cookie;
/*
* Make sure that on error condition we return "no valid mappings."
*/
map->dm_mapsize = 0;
map->dm_nsegs = 0;
KASSERT(map->dm_maxsegsz <= map->_dm_maxmaxsegsz);
resid = uio->uio_resid;
iov = uio->uio_iov;
vm = uio->uio_vmspace;
error = 0;
for (i = 0; i < uio->uio_iovcnt && resid != 0 && error == 0; i++) {
/*
* Now at the first iovec to load. Load each iovec
* until we have exhausted the residual count.
*/
minlen = resid < iov[i].iov_len ? resid : iov[i].iov_len;
addr = (void *)iov[i].iov_base;
error = _bus_dmamap_load_buffer(t, map, addr, minlen,
vm, flags);
resid -= minlen;
}
if (error == 0) {
map->dm_mapsize = uio->uio_resid;
return 0;
}
map->dm_nsegs = 0;
if (cookie == NULL ||
((cookie->id_flags & X86_DMA_MIGHT_NEED_BOUNCE) == 0))
return error;
STAT_INCR(bounces);
/*
* Allocate bounce pages, if necessary.
*/
if ((cookie->id_flags & X86_DMA_HAS_BOUNCE) == 0) {
error = _bus_dma_alloc_bouncebuf(t, map, uio->uio_resid,
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 = uio;
cookie->id_origbuflen = uio->uio_resid;
cookie->id_buftype = X86_DMA_BUFTYPE_UIO;
error = _bus_dmamap_load(t, map, cookie->id_bouncebuf,
uio->uio_resid, NULL, flags);
if (error)
return (error);
/* ...so _bus_dmamap_sync() knows we're bouncing */
cookie->id_flags |= X86_DMA_IS_BOUNCING;
return (0);
}
/*
* Like _bus_dmamap_load(), but for raw memory allocated with
* bus_dmamem_alloc().
*/
int
_bus_dmamap_load_raw(bus_dma_tag_t t, bus_dmamap_t map,
bus_dma_segment_t *segs, int nsegs,
bus_size_t size, int flags)
{
panic("_bus_dmamap_load_raw: not implemented");
}
/*
* Unload a DMA map.
*/
void
_bus_dmamap_unload(bus_dma_tag_t t, bus_dmamap_t map)
{
struct x86_bus_dma_cookie *cookie = map->_dm_cookie;
/*
* If we have bounce pages, free them, unless they're
* reserved for our exclusive use.
*/
if (cookie != NULL) {
cookie->id_flags &= ~X86_DMA_IS_BOUNCING;
cookie->id_buftype = X86_DMA_BUFTYPE_INVALID;
}
map->dm_maxsegsz = map->_dm_maxmaxsegsz;
map->dm_mapsize = 0;
map->dm_nsegs = 0;
}
/*
* Synchronize a DMA map.
*/
void
_bus_dmamap_sync(bus_dma_tag_t t, bus_dmamap_t map, bus_addr_t offset,
bus_size_t len, int ops)
{
struct x86_bus_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("_bus_dmamap_sync: mix PRE and POST");
#ifdef DIAGNOSTIC
if ((ops & (BUS_DMASYNC_PREWRITE|BUS_DMASYNC_POSTREAD)) != 0) {
if (offset >= map->dm_mapsize)
panic("_bus_dmamap_sync: bad offset");
if ((offset + len) > map->dm_mapsize)
panic("_bus_dmamap_sync: bad length");
}
#endif
/*
* If we're not bouncing, just return; nothing to do.
*/
if (len == 0 || cookie == NULL ||
(cookie->id_flags & X86_DMA_IS_BOUNCING) == 0)
goto end;
switch (cookie->id_buftype) {
case X86_DMA_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 X86_DMA_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, char *) + moff,
(char *)cookie->id_bouncebuf + offset,
minlen);
moff = 0;
len -= minlen;
offset += minlen;
}
}
/*
* Nothing to do for post-write.
*/
break;
}
case X86_DMA_BUFTYPE_UIO:
{
struct uio *uio;
uio = (struct uio *)cookie->id_origbuf;
/*
* Nothing to do for pre-read.
*/
if (ops & BUS_DMASYNC_PREWRITE) {
/*
* Copy the caller's buffer to the bounce buffer.
*/
_bus_dma_uiomove((char *)cookie->id_bouncebuf + offset,
uio, len, UIO_WRITE);
}
if (ops & BUS_DMASYNC_POSTREAD) {
_bus_dma_uiomove((char *)cookie->id_bouncebuf + offset,
uio, len, UIO_READ);
}
/*
* Nothing to do for post-write.
*/
break;
}
case X86_DMA_BUFTYPE_RAW:
panic("_bus_dmamap_sync: X86_DMA_BUFTYPE_RAW");
break;
case X86_DMA_BUFTYPE_INVALID:
panic("_bus_dmamap_sync: X86_DMA_BUFTYPE_INVALID");
break;
default:
printf("unknown buffer type %d\n", cookie->id_buftype);
panic("_bus_dmamap_sync");
}
end:
if (ops & (BUS_DMASYNC_PREWRITE|BUS_DMASYNC_POSTWRITE)) {
/*
* from the memory POV a load can be reordered before a store
* (a load can fetch data from the write buffers, before
* data hits the cache or memory), a mfence avoids it.
*/
x86_mfence();
} else if (ops & (BUS_DMASYNC_PREREAD|BUS_DMASYNC_POSTREAD)) {
/*
* all past reads should have completed at before this point,
* and futur reads should not have started yet.
*/
x86_lfence();
}
}
/*
* Allocate memory safe for DMA.
*/
int
_bus_dmamem_alloc(bus_dma_tag_t t, bus_size_t size, bus_size_t alignment,
bus_size_t boundary, bus_dma_segment_t *segs, int nsegs, int *rsegs,
int flags)
{
bus_addr_t high;
if (t->_bounce_alloc_hi != 0 && _BUS_AVAIL_END > t->_bounce_alloc_hi)
high = trunc_page(t->_bounce_alloc_hi);
else
high = trunc_page(_BUS_AVAIL_END);
return (_BUS_DMAMEM_ALLOC_RANGE(t, size, alignment, boundary,
segs, nsegs, rsegs, flags, t->_bounce_alloc_lo, high));
}
static int
_bus_dma_alloc_bouncebuf(bus_dma_tag_t t, bus_dmamap_t map,
bus_size_t size, int flags)
{
struct x86_bus_dma_cookie *cookie = map->_dm_cookie;
int error = 0;
#ifdef DIAGNOSTIC
if (cookie == NULL)
panic("_bus_dma_alloc_bouncebuf: no cookie");
#endif
cookie->id_bouncebuflen = round_page(size);
error = _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,
(void **)&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 |= X86_DMA_HAS_BOUNCE;
STAT_INCR(nbouncebufs);
}
return (error);
}
static void
_bus_dma_free_bouncebuf(bus_dma_tag_t t, bus_dmamap_t map)
{
struct x86_bus_dma_cookie *cookie = map->_dm_cookie;
#ifdef DIAGNOSTIC
if (cookie == NULL)
panic("_bus_dma_alloc_bouncebuf: no cookie");
#endif
STAT_DECR(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 &= ~X86_DMA_HAS_BOUNCE;
}
/*
* This function does the same as uiomove, but takes an explicit
* direction, and does not update the uio structure.
*/
static int
_bus_dma_uiomove(void *buf, struct uio *uio, size_t n, int direction)
{
struct iovec *iov;
int error;
struct vmspace *vm;
char *cp;
size_t resid, cnt;
int i;
iov = uio->uio_iov;
vm = uio->uio_vmspace;
cp = buf;
resid = n;
for (i = 0; i < uio->uio_iovcnt && resid > 0; i++) {
iov = &uio->uio_iov[i];
if (iov->iov_len == 0)
continue;
cnt = MIN(resid, iov->iov_len);
if (!VMSPACE_IS_KERNEL_P(vm) &&
(curlwp->l_cpu->ci_schedstate.spc_flags & SPCF_SHOULDYIELD)
!= 0) {
preempt();
}
if (direction == UIO_READ) {
error = copyout_vmspace(vm, cp, iov->iov_base, cnt);
} else {
error = copyin_vmspace(vm, iov->iov_base, cp, cnt);
}
if (error)
return (error);
cp += cnt;
resid -= cnt;
}
return (0);
}
/*
* Common function for freeing DMA-safe memory. May be called by
* bus-specific DMA memory free functions.
*/
void
_bus_dmamem_free(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs)
{
struct vm_page *m;
bus_addr_t addr;
struct pglist mlist;
int curseg;
/*
* Build a list of pages to free back to the VM system.
*/
TAILQ_INIT(&mlist);
for (curseg = 0; curseg < nsegs; curseg++) {
for (addr = segs[curseg].ds_addr;
addr < (segs[curseg].ds_addr + segs[curseg].ds_len);
addr += PAGE_SIZE) {
m = _BUS_BUS_TO_VM_PAGE(addr);
TAILQ_INSERT_TAIL(&mlist, m, pageq.queue);
}
}
uvm_pglistfree(&mlist);
}
/*
* Common function for mapping DMA-safe memory. May be called by
* bus-specific DMA memory map functions.
* This supports BUS_DMA_NOCACHE.
*/
int
_bus_dmamem_map(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs,
size_t size, void **kvap, int flags)
{
vaddr_t sva, va, eva;
bus_addr_t addr;
int curseg;
int nocache;
pt_entry_t *pte, opte, xpte;
const uvm_flag_t kmflags =
(flags & BUS_DMA_NOWAIT) != 0 ? UVM_KMF_NOWAIT : 0;
size = round_page(size);
nocache = (flags & BUS_DMA_NOCACHE) != 0;
va = uvm_km_alloc(kernel_map, size, 0, UVM_KMF_VAONLY | kmflags);
if (va == 0)
return (ENOMEM);
*kvap = (void *)va;
sva = va;
eva = sva + size;
xpte = 0;
for (curseg = 0; curseg < nsegs; curseg++) {
for (addr = segs[curseg].ds_addr;
addr < (segs[curseg].ds_addr + segs[curseg].ds_len);
addr += PAGE_SIZE, va += PAGE_SIZE, size -= PAGE_SIZE) {
if (size == 0)
panic("_bus_dmamem_map: size botch");
_BUS_PMAP_ENTER(pmap_kernel(), va, addr,
VM_PROT_READ | VM_PROT_WRITE,
PMAP_WIRED | VM_PROT_READ | VM_PROT_WRITE);
/*
* mark page as non-cacheable
*/
if (nocache) {
pte = kvtopte(va);
opte = *pte;
if ((opte & PG_N) == 0) {
pmap_pte_setbits(pte, PG_N);
xpte |= opte;
}
}
}
}
#ifndef XEN /* XXX */
if ((xpte & (PG_V | PG_U)) == (PG_V | PG_U)) {
kpreempt_disable();
pmap_tlb_shootdown(pmap_kernel(), sva, eva, xpte);
kpreempt_enable();
}
pmap_update(pmap_kernel());
#endif
return (0);
}
/*
* Common function for unmapping DMA-safe memory. May be called by
* bus-specific DMA memory unmapping functions.
*/
void
_bus_dmamem_unmap(bus_dma_tag_t t, void *kva, size_t size)
{
pt_entry_t *pte, opte;
vaddr_t va, sva, eva;
#ifdef DIAGNOSTIC
if ((u_long)kva & PGOFSET)
panic("_bus_dmamem_unmap");
#endif
size = round_page(size);
sva = (vaddr_t)kva;
eva = sva + size;
/*
* mark pages cacheable again.
*/
for (va = sva; va < eva; va += PAGE_SIZE) {
pte = kvtopte(va);
opte = *pte;
if ((opte & PG_N) != 0)
pmap_pte_clearbits(pte, PG_N);
}
pmap_remove(pmap_kernel(), (vaddr_t)kva, (vaddr_t)kva + size);
pmap_update(pmap_kernel());
uvm_km_free(kernel_map, (vaddr_t)kva, size, UVM_KMF_VAONLY);
}
/*
* Common function for mmap(2)'ing DMA-safe memory. May be called by
* bus-specific DMA mmap(2)'ing functions.
*/
paddr_t
_bus_dmamem_mmap(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs,
off_t off, int prot, int flags)
{
int i;
for (i = 0; i < nsegs; i++) {
#ifdef DIAGNOSTIC
if (off & PGOFSET)
panic("_bus_dmamem_mmap: offset unaligned");
if (segs[i].ds_addr & PGOFSET)
panic("_bus_dmamem_mmap: segment unaligned");
if (segs[i].ds_len & PGOFSET)
panic("_bus_dmamem_mmap: segment size not multiple"
" of page size");
#endif
if (off >= segs[i].ds_len) {
off -= segs[i].ds_len;
continue;
}
return (x86_btop(_BUS_BUS_TO_PHYS(segs[i].ds_addr + off)));
}
/* Page not found. */
return (-1);
}
/**********************************************************************
* DMA utility functions
**********************************************************************/
/*
* Utility function to load a linear buffer.
*/
static int
_bus_dmamap_load_buffer(bus_dma_tag_t t, bus_dmamap_t map, void *buf,
bus_size_t buflen, struct vmspace *vm, int flags)
{
bus_size_t sgsize;
bus_addr_t curaddr;
vaddr_t vaddr = (vaddr_t)buf;
pmap_t pmap;
if (vm != NULL)
pmap = vm_map_pmap(&vm->vm_map);
else
pmap = pmap_kernel();
while (buflen > 0) {
int error;
/*
* Get the bus address for this segment.
*/
curaddr = _BUS_VIRT_TO_BUS(pmap, vaddr);
/*
* If we're beyond the bounce threshold, notify
* the caller.
*/
if (map->_dm_bounce_thresh != 0 &&
curaddr >= map->_dm_bounce_thresh)
return (EINVAL);
/*
* Compute the segment size, and adjust counts.
*/
sgsize = PAGE_SIZE - ((u_long)vaddr & PGOFSET);
if (buflen < sgsize)
sgsize = buflen;
error = _bus_dmamap_load_busaddr(t, map, curaddr, sgsize);
if (error)
return error;
vaddr += sgsize;
buflen -= sgsize;
}
return (0);
}
int
_bus_dmatag_subregion(bus_dma_tag_t tag, bus_addr_t min_addr,
bus_addr_t max_addr, bus_dma_tag_t *newtag, int flags)
{
if ((tag->_bounce_thresh != 0 && max_addr >= tag->_bounce_thresh) &&
(tag->_bounce_alloc_hi != 0 && max_addr >= tag->_bounce_alloc_hi) &&
(min_addr <= tag->_bounce_alloc_lo)) {
*newtag = tag;
/* if the tag must be freed, add a reference */
if (tag->_tag_needs_free)
(tag->_tag_needs_free)++;
return 0;
}
if ((*newtag = malloc(sizeof(struct x86_bus_dma_tag), M_DMAMAP,
(flags & BUS_DMA_NOWAIT) ? M_NOWAIT : M_WAITOK)) == NULL)
return ENOMEM;
**newtag = *tag;
(*newtag)->_tag_needs_free = 1;
if (tag->_bounce_thresh == 0 || max_addr < tag->_bounce_thresh)
(*newtag)->_bounce_thresh = max_addr;
if (tag->_bounce_alloc_hi == 0 || max_addr < tag->_bounce_alloc_hi)
(*newtag)->_bounce_alloc_hi = max_addr;
if (min_addr > tag->_bounce_alloc_lo)
(*newtag)->_bounce_alloc_lo = min_addr;
return 0;
}
void
_bus_dmatag_destroy(bus_dma_tag_t tag)
{
switch (tag->_tag_needs_free) {
case 0:
break; /* not allocated with malloc */
case 1:
free(tag, M_DMAMAP); /* last reference to tag */
break;
default:
(tag->_tag_needs_free)--; /* one less reference */
}
}
void
bus_dmamap_sync(bus_dma_tag_t t, bus_dmamap_t p, bus_addr_t o, bus_size_t l,
int ops)
{
if (ops & BUS_DMASYNC_POSTREAD)
x86_lfence();
if (t->_dmamap_sync)
(*t->_dmamap_sync)(t, p, o, l, ops);
}
int
bus_dmamap_create(bus_dma_tag_t tag, bus_size_t size, int nsegments,
bus_size_t maxsegsz, bus_size_t boundary, int flags,
bus_dmamap_t *dmamp)
{
return (*tag->_dmamap_create)(tag, size, nsegments, maxsegsz,
boundary, flags, dmamp);
}
void
bus_dmamap_destroy(bus_dma_tag_t tag, bus_dmamap_t dmam)
{
(*tag->_dmamap_destroy)(tag, dmam);
}
int
bus_dmamap_load(bus_dma_tag_t tag, bus_dmamap_t dmam, void *buf,
bus_size_t buflen, struct proc *p, int flags)
{
return (*tag->_dmamap_load)(tag, dmam, buf, buflen, p, flags);
}
int
bus_dmamap_load_mbuf(bus_dma_tag_t tag, bus_dmamap_t dmam,
struct mbuf *chain, int flags)
{
return (*tag->_dmamap_load_mbuf)(tag, dmam, chain, flags);
}
int
bus_dmamap_load_uio(bus_dma_tag_t tag, bus_dmamap_t dmam,
struct uio *uio, int flags)
{
return (*tag->_dmamap_load_uio)(tag, dmam, uio, flags);
}
int
bus_dmamap_load_raw(bus_dma_tag_t tag, bus_dmamap_t dmam,
bus_dma_segment_t *segs, int nsegs,
bus_size_t size, int flags)
{
return (*tag->_dmamap_load_raw)(tag, dmam, segs, nsegs,
size, flags);
}
void
bus_dmamap_unload(bus_dma_tag_t tag, bus_dmamap_t dmam)
{
(*tag->_dmamap_unload)(tag, dmam);
}
int
bus_dmamem_alloc(bus_dma_tag_t tag, bus_size_t size, bus_size_t alignment,
bus_size_t boundary, bus_dma_segment_t *segs, int nsegs,
int *rsegs, int flags)
{
return (*tag->_dmamem_alloc)(tag, size, alignment, boundary, segs,
nsegs, rsegs, flags);
}
void
bus_dmamem_free(bus_dma_tag_t tag, bus_dma_segment_t *segs, int nsegs)
{
(*tag->_dmamem_free)(tag, segs, nsegs);
}
int
bus_dmamem_map(bus_dma_tag_t tag, bus_dma_segment_t *segs, int nsegs,
size_t size, void **kvap, int flags)
{
return (*tag->_dmamem_map)(tag, segs, nsegs, size, kvap, flags);
}
void
bus_dmamem_unmap(bus_dma_tag_t tag, void *kva, size_t size)
{
(*tag->_dmamem_unmap)(tag, kva, size);
}
paddr_t
bus_dmamem_mmap(bus_dma_tag_t tag, bus_dma_segment_t *segs, int nsegs,
off_t off, int prot, int flags)
{
return (*tag->_dmamem_mmap)(tag, segs, nsegs, off, prot, flags);
}
int
bus_dmatag_subregion(bus_dma_tag_t tag, bus_addr_t min_addr,
bus_addr_t max_addr, bus_dma_tag_t *newtag, int flags)
{
return (*tag->_dmatag_subregion)(tag, min_addr, max_addr, newtag,
flags);
}
void
bus_dmatag_destroy(bus_dma_tag_t tag)
{
(*tag->_dmatag_destroy)(tag);
}