/* $OpenBSD: isa_machdep.c,v 1.12 2007/04/28 03:55:40 jsg Exp $ */
/* $NetBSD: isa_machdep.c,v 1.22 1997/06/12 23:57:32 thorpej Exp $ */
#define ISA_DMA_STATS
/*-
* Copyright (c) 1996, 1997 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* 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.
*/
/*-
* Copyright (c) 1993, 1994, 1996, 1997
* Charles M. Hannum. All rights reserved.
* Copyright (c) 1991 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* William Jolitz.
*
* 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.
*
* @(#)isa.c 7.2 (Berkeley) 5/13/91
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/syslog.h>
#include <sys/device.h>
#include <sys/malloc.h>
#include <sys/proc.h>
#include <uvm/uvm_extern.h>
#include "ioapic.h"
#if NIOAPIC > 0
#include <machine/i82093var.h>
#include <machine/mpbiosvar.h>
#endif
#define _X86_BUS_DMA_PRIVATE
#include <machine/bus.h>
#include <machine/intr.h>
#include <machine/pio.h>
#include <machine/cpufunc.h>
#include <machine/i8259.h>
#include <dev/isa/isareg.h>
#include <dev/isa/isavar.h>
#if 0
#include <dev/isa/isadmavar.h>
#endif
#include <i386/isa/isa_machdep.h>
#include "isadma.h"
extern paddr_t avail_end;
#define IDTVEC(name) __CONCAT(X,name)
/* default interrupt vector table entries */
typedef int (*vector)(void);
extern vector IDTVEC(intr)[];
void isa_strayintr(int);
int fakeintr(void *);
#if NISADMA > 0
int _isa_bus_dmamap_create(bus_dma_tag_t, bus_size_t, int,
bus_size_t, bus_size_t, int, bus_dmamap_t *);
void _isa_bus_dmamap_destroy(bus_dma_tag_t, bus_dmamap_t);
int _isa_bus_dmamap_load(bus_dma_tag_t, bus_dmamap_t, void *,
bus_size_t, struct proc *, int);
int _isa_bus_dmamap_load_mbuf(bus_dma_tag_t, bus_dmamap_t,
struct mbuf *, int);
int _isa_bus_dmamap_load_uio(bus_dma_tag_t, bus_dmamap_t,
struct uio *, int);
int _isa_bus_dmamap_load_raw(bus_dma_tag_t, bus_dmamap_t,
bus_dma_segment_t *, int, bus_size_t, int);
void _isa_bus_dmamap_unload(bus_dma_tag_t, bus_dmamap_t);
void _isa_bus_dmamap_sync(bus_dma_tag_t, bus_dmamap_t,
bus_addr_t, bus_size_t, int);
int _isa_bus_dmamem_alloc(bus_dma_tag_t, bus_size_t, bus_size_t,
bus_size_t, bus_dma_segment_t *, int, int *, int);
void _isa_bus_dmamem_free(bus_dma_tag_t,
bus_dma_segment_t *, int);
int _isa_bus_dmamem_map(bus_dma_tag_t, bus_dma_segment_t *,
int, size_t, caddr_t *, int);
void _isa_bus_dmamem_unmap(bus_dma_tag_t, caddr_t, size_t);
paddr_t _isa_bus_dmamem_mmap(bus_dma_tag_t, bus_dma_segment_t *,
int, off_t, int, int);
int _isa_dma_check_buffer(void *, bus_size_t, int, bus_size_t,
struct proc *);
int _isa_dma_alloc_bouncebuf(bus_dma_tag_t, bus_dmamap_t,
bus_size_t, int);
void _isa_dma_free_bouncebuf(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 x86_bus_dma_tag isa_bus_dma_tag = {
NULL, /* _cookie */
_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,
_isa_bus_dmamem_alloc,
_isa_bus_dmamem_free,
_isa_bus_dmamem_map,
_isa_bus_dmamem_unmap,
_isa_bus_dmamem_mmap,
};
#endif /* NISADMA > 0 */
#define GICODE_SEL 10
u_long intrstray[ICU_LEN];
/*
* Caught a stray interrupt, notify
*/
void
isa_strayintr(int irq)
{
/*
* Stray interrupts on irq 7 occur when an interrupt line is raised
* and then lowered before the CPU acknowledges it. This generally
* means either the device is screwed or something is cli'ing too
* long and it's timing out.
*/
if (++intrstray[irq] <= 5)
log(LOG_ERR, "stray interrupt %d%s\n", irq,
intrstray[irq] >= 5 ? "; stopped logging" : "");
}
int intrtype[ICU_LEN], intrmask[ICU_LEN], intrlevel[ICU_LEN];
int iminlevel[ICU_LEN], imaxlevel[ICU_LEN];
struct intrhand *intrhand[ICU_LEN];
int
fakeintr(void *arg)
{
return 0;
}
#define LEGAL_IRQ(x) ((x) >= 0 && (x) < ICU_LEN && (x) != 2)
int
isa_intr_alloc(isa_chipset_tag_t ic, int mask, int type, int *irq)
{
int i, bestirq, count;
int tmp;
struct intrhand **p, *q;
if (type == IST_NONE)
panic("intr_alloc: bogus type");
bestirq = -1;
count = -1;
/* some interrupts should never be dynamically allocated */
mask &= 0xdef8;
/*
* XXX some interrupts will be used later (6 for fdc, 12 for pms).
* the right answer is to do "breadth-first" searching of devices.
*/
mask &= 0xefbf;
for (i = 0; i < ICU_LEN; i++) {
if (LEGAL_IRQ(i) == 0 || (mask & (1<<i)) == 0)
continue;
switch(intrtype[i]) {
case IST_NONE:
/*
* if nothing's using the irq, just return it
*/
*irq = i;
return (0);
case IST_EDGE:
case IST_LEVEL:
if (type != intrtype[i])
continue;
/*
* if the irq is shareable, count the number of other
* handlers, and if it's smaller than the last irq like
* this, remember it
*
* XXX We should probably also consider the
* interrupt level and stick IPL_TTY with other
* IPL_TTY, etc.
*/
for (p = &intrhand[i], tmp = 0; (q = *p) != NULL;
p = &q->ih_next, tmp++)
;
if ((bestirq == -1) || (count > tmp)) {
bestirq = i;
count = tmp;
}
break;
case IST_PULSE:
/* this just isn't shareable */
continue;
}
}
if (bestirq == -1)
return (1);
*irq = bestirq;
return (0);
}
/*
* Just check to see if an IRQ is available/can be shared.
* 0 = interrupt not available
* 1 = interrupt shareable
* 2 = interrupt all to ourself
*/
int
isa_intr_check(isa_chipset_tag_t ic, int irq, int type)
{
if (!LEGAL_IRQ(irq) || type == IST_NONE)
return (0);
switch (intrtype[irq]) {
case IST_NONE:
return (2);
break;
case IST_LEVEL:
if (type != intrtype[irq])
return (0);
return (1);
break;
case IST_EDGE:
case IST_PULSE:
if (type != IST_NONE)
return (0);
}
return (1);
}
/*
* Set up an interrupt handler to start being called.
* XXX PRONE TO RACE CONDITIONS, UGLY, 'INTERESTING' INSERTION ALGORITHM.
*/
void *
isa_intr_establish(isa_chipset_tag_t ic, int irq, int type, int level,
int (*ih_fun)(void *), void *ih_arg, char *ih_what)
{
struct pic *pic = &i8259_pic;
int pin = irq;
#if NIOAPIC > 0
struct mp_intr_map *mip;
if (mp_busses != NULL) {
if (mp_isa_bus == NULL)
panic("no isa bus");
for (mip = mp_isa_bus->mb_intrs; mip != NULL;
mip = mip->next) {
if (mip->bus_pin == pin) {
pin = APIC_IRQ_PIN(mip->ioapic_ih);
pic = &mip->ioapic->sc_pic;
break;
}
}
}
#endif
KASSERT(pic);
return intr_establish(irq, pic, pin, type, level, ih_fun,
ih_arg, ih_what);
}
/*
* Deregister an interrupt handler.
*/
void
isa_intr_disestablish(isa_chipset_tag_t ic, void *arg)
{
intr_disestablish(arg);
return;
}
void
isa_attach_hook(struct device *parent, struct device *self,
struct isabus_attach_args *iba)
{
extern int isa_has_been_seen;
/*
* Notify others that might need to know that the ISA bus
* has now been attached.
*/
if (isa_has_been_seen)
panic("isaattach: ISA bus already seen!");
isa_has_been_seen = 1;
}
#if NISADMA > 0
/**********************************************************************
* 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(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_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 x86_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 / NBPG) + 1. If
* the caller can't handle that many segments (e.g. the
* ISA DMA controller), we may have to bounce it as well.
*/
cookieflags = 0;
if ((avail_end > ISA_DMA_BOUNCE_THRESHOLD &&
(flags & ISABUS_DMA_32BIT) == 0) ||
((map->_dm_size / NBPG) + 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_DEVBUF,
(flags & BUS_DMA_NOWAIT) ? M_NOWAIT : M_WAITOK)) == NULL) {
error = ENOMEM;
goto out;
}
bzero(cookiestore, cookiesize);
cookie = (struct x86_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_DEVBUF);
_bus_dmamap_destroy(t, map);
}
return (error);
}
/*
* Destroy an ISA DMA map.
*/
void
_isa_bus_dmamap_destroy(bus_dma_tag_t t, bus_dmamap_t map)
{
struct x86_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_DEVBUF);
_bus_dmamap_destroy(t, map);
}
/*
* Load an ISA DMA map with a linear buffer.
*/
int
_isa_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_isa_dma_cookie *cookie = map->_dm_cookie;
int error;
STAT_INCR(isa_dma_stats_loads);
/*
* Check to see if we might need to bounce the transfer.
*/
if (cookie->id_flags & ID_MIGHT_NEED_BOUNCE) {
/*
* Check if all pages are below the bounce
* threshold. If they are, don't bother bouncing.
*/
if (_isa_dma_check_buffer(buf, buflen,
map->_dm_segcnt, map->_dm_boundary, p) == 0)
return (_bus_dmamap_load(t, map, buf, buflen,
p, flags));
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;
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);
}
/* ...so _isa_bus_dmamap_sync() knows we're bouncing */
cookie->id_flags |= ID_IS_BOUNCING;
} else {
/*
* Just use the generic load function.
*/
error = _bus_dmamap_load(t, map, buf, buflen, p, flags);
}
return (error);
}
/*
* Like _isa_bus_dmamap_load(), but for mbufs.
*/
int
_isa_bus_dmamap_load_mbuf(bus_dma_tag_t t, bus_dmamap_t map, struct mbuf *m,
int flags)
{
panic("_isa_bus_dmamap_load_mbuf: not implemented");
}
/*
* Like _isa_bus_dmamap_load(), but for uios.
*/
int
_isa_bus_dmamap_load_uio(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(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(bus_dma_tag_t t, bus_dmamap_t map)
{
struct x86_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;
/*
* Do the generic bits of the unload.
*/
_bus_dmamap_unload(t, map);
}
/*
* Synchronize an ISA DMA map.
*/
void
_isa_bus_dmamap_sync(bus_dma_tag_t t, bus_dmamap_t map, bus_addr_t offset,
bus_size_t len, int op)
{
struct x86_isa_dma_cookie *cookie = map->_dm_cookie;
#ifdef DEBUG
if ((op & (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
switch (op) {
case BUS_DMASYNC_PREREAD:
/*
* Nothing to do for pre-read.
*/
break;
case BUS_DMASYNC_PREWRITE:
/*
* If we're bouncing this transfer, copy the
* caller's buffer to the bounce buffer.
*/
if (cookie->id_flags & ID_IS_BOUNCING)
bcopy(cookie->id_origbuf + offset,
cookie->id_bouncebuf + offset,
len);
break;
case BUS_DMASYNC_POSTREAD:
/*
* If we're bouncing this transfer, copy the
* bounce buffer to the caller's buffer.
*/
if (cookie->id_flags & ID_IS_BOUNCING)
bcopy(cookie->id_bouncebuf + offset,
cookie->id_origbuf + offset,
len);
break;
case BUS_DMASYNC_POSTWRITE:
/*
* Nothing to do for post-write.
*/
break;
}
#if 0
/* This is a noop anyhow, so why bother calling it? */
_bus_dmamap_sync(t, map, op);
#endif
}
/*
* Allocate memory safe for ISA DMA.
*/
int
_isa_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)
{
int error;
/* Try in ISA addressable region first */
error = _bus_dmamem_alloc_range(t, size, alignment, boundary,
segs, nsegs, rsegs, flags, 0, ISA_DMA_BOUNCE_THRESHOLD);
if (!error)
return (error);
/* Otherwise try anywhere (we'll bounce later) */
error = _bus_dmamem_alloc_range(t, size, alignment, boundary,
segs, nsegs, rsegs, flags, 0, trunc_page(avail_end));
return (error);
}
/*
* Free memory safe for ISA DMA.
*/
void
_isa_bus_dmamem_free(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs)
{
_bus_dmamem_free(t, segs, nsegs);
}
/*
* Map ISA DMA-safe memory into kernel virtual address space.
*/
int
_isa_bus_dmamem_map(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs,
size_t size, caddr_t *kvap, int flags)
{
return (_bus_dmamem_map(t, segs, nsegs, size, kvap, flags));
}
/*
* Unmap ISA DMA-safe memory from kernel virtual address space.
*/
void
_isa_bus_dmamem_unmap(bus_dma_tag_t t, caddr_t kva, size_t size)
{
_bus_dmamem_unmap(t, kva, size);
}
/*
* mmap(2) ISA DMA-safe memory.
*/
paddr_t
_isa_bus_dmamem_mmap(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs,
off_t off, int prot, int flags)
{
return (_bus_dmamem_mmap(t, segs, nsegs, off, prot, flags));
}
/**********************************************************************
* ISA DMA utility functions
**********************************************************************/
/*
* Return 0 if all pages in the passed buffer lie within the DMA'able
* range RAM.
*/
int
_isa_dma_check_buffer(void *buf, bus_size_t buflen, int segcnt,
bus_size_t boundary, struct proc *p)
{
vaddr_t vaddr = (vaddr_t)buf;
vaddr_t endva;
paddr_t pa, lastpa;
u_long pagemask = ~(boundary - 1);
pmap_t pmap;
int nsegs;
endva = round_page(vaddr + buflen);
nsegs = 1;
lastpa = 0;
if (p != NULL)
pmap = p->p_vmspace->vm_map.pmap;
else
pmap = pmap_kernel();
for (; vaddr < endva; vaddr += NBPG) {
/*
* Get physical address for this segment.
*/
pmap_extract(pmap, (vaddr_t)vaddr, &pa);
pa = trunc_page(pa);
/*
* Is it below the DMA'able threshold?
*/
if (pa > ISA_DMA_BOUNCE_THRESHOLD)
return (EINVAL);
if (lastpa) {
/*
* Check excessive segment count.
*/
if (lastpa + NBPG != pa) {
if (++nsegs > segcnt)
return (EFBIG);
}
/*
* Check boundary restriction.
*/
if (boundary) {
if ((lastpa ^ pa) & pagemask)
return (EINVAL);
}
}
lastpa = pa;
}
return (0);
}
int
_isa_dma_alloc_bouncebuf(bus_dma_tag_t t, bus_dmamap_t map, bus_size_t size,
int flags)
{
struct x86_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,
NBPG, map->_dm_boundary, cookie->id_bouncesegs,
map->_dm_segcnt, &cookie->id_nbouncesegs, flags);
if (error)
goto out;
error = _isa_bus_dmamem_map(t, cookie->id_bouncesegs,
cookie->id_nbouncesegs, cookie->id_bouncebuflen,
(caddr_t *)&cookie->id_bouncebuf, flags);
out:
if (error) {
_isa_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(bus_dma_tag_t t, bus_dmamap_t map)
{
struct x86_isa_dma_cookie *cookie = map->_dm_cookie;
STAT_DECR(isa_dma_stats_nbouncebufs);
_isa_bus_dmamem_unmap(t, cookie->id_bouncebuf,
cookie->id_bouncebuflen);
_isa_bus_dmamem_free(t, cookie->id_bouncesegs,
cookie->id_nbouncesegs);
cookie->id_bouncebuflen = 0;
cookie->id_nbouncesegs = 0;
cookie->id_flags &= ~ID_HAS_BOUNCE;
}
#endif /* NISADMA > 0 */
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