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|
/* $OpenBSD: bus_dma.c,v 1.28 2012/05/20 11:41:11 miod Exp $ */
/*
* Copyright (c) 2003-2004 Opsycon AB (www.opsycon.se / www.opsycon.com)
*
* 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 AUTHOR ``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 AUTHOR 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) 1996, 1997, 1998 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.
*
* 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/proc.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <uvm/uvm.h>
#include <mips64/archtype.h>
#include <mips64/cache.h>
#include <machine/cpu.h>
#include <machine/autoconf.h>
#include <machine/bus.h>
/*
* Common function for DMA map creation. May be called by bus-specific
* DMA map creation functions.
*/
int
_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 machine_bus_dmamap *map;
void *mapstore;
size_t 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).
*/
mapsize = sizeof(struct machine_bus_dmamap) +
(sizeof(bus_dma_segment_t) * (nsegments - 1));
if ((mapstore = malloc(mapsize, M_DEVBUF, (flags & BUS_DMA_NOWAIT) ?
(M_NOWAIT | M_ZERO) : (M_WAITOK | M_ZERO))) == NULL)
return (ENOMEM);
map = (struct machine_bus_dmamap *)mapstore;
map->_dm_size = size;
map->_dm_segcnt = nsegments;
map->_dm_maxsegsz = maxsegsz;
map->_dm_boundary = boundary;
map->_dm_flags = flags & ~(BUS_DMA_WAITOK|BUS_DMA_NOWAIT);
*dmamp = map;
return (0);
}
/*
* Common function for DMA map destruction. May be called by bus-specific
* DMA map destruction functions.
*/
void
_dmamap_destroy(bus_dma_tag_t t, bus_dmamap_t map)
{
free(map, M_DEVBUF);
}
/*
* Common function for loading a DMA map with a linear buffer. May
* be called by bus-specific DMA map load functions.
*/
int
_dmamap_load(bus_dma_tag_t t, bus_dmamap_t map, void *buf, bus_size_t buflen,
struct proc *p, int flags)
{
paddr_t lastaddr;
int seg, error;
/*
* Make sure that on error condition we return "no valid mappings".
*/
map->dm_nsegs = 0;
map->dm_mapsize = 0;
if (buflen > map->_dm_size)
return (EINVAL);
seg = 0;
error = (*t->_dmamap_load_buffer)(t, map, buf, buflen, p, flags,
&lastaddr, &seg, 1);
if (error == 0) {
map->dm_nsegs = seg + 1;
map->dm_mapsize = buflen;
}
return (error);
}
/*
* Like _bus_dmamap_load(), but for mbufs.
*/
int
_dmamap_load_mbuf(bus_dma_tag_t t, bus_dmamap_t map, struct mbuf *m0, int flags)
{
paddr_t lastaddr;
int seg, error, first;
struct mbuf *m;
/*
* Make sure that on error condition we return "no valid mappings".
*/
map->dm_nsegs = 0;
map->dm_mapsize = 0;
#ifdef DIAGNOSTIC
if ((m0->m_flags & M_PKTHDR) == 0)
panic("_dmamap_load_mbuf: no packet header");
#endif
if (m0->m_pkthdr.len > map->_dm_size)
return (EINVAL);
first = 1;
seg = 0;
error = 0;
for (m = m0; m != NULL && error == 0; m = m->m_next) {
if (m->m_len == 0)
continue;
error = (*t->_dmamap_load_buffer)(t, map, m->m_data, m->m_len,
NULL, flags, &lastaddr, &seg, first);
first = 0;
}
if (error == 0) {
map->dm_nsegs = seg + 1;
map->dm_mapsize = m0->m_pkthdr.len;
}
return (error);
}
/*
* Like _dmamap_load(), but for uios.
*/
int
_dmamap_load_uio(bus_dma_tag_t t, bus_dmamap_t map, struct uio *uio, int flags)
{
paddr_t lastaddr;
int seg, i, error, first;
bus_size_t minlen, resid;
struct proc *p = NULL;
struct iovec *iov;
void *addr;
/*
* Make sure that on error condition we return "no valid mappings".
*/
map->dm_nsegs = 0;
map->dm_mapsize = 0;
resid = uio->uio_resid;
iov = uio->uio_iov;
if (uio->uio_segflg == UIO_USERSPACE) {
p = uio->uio_procp;
#ifdef DIAGNOSTIC
if (p == NULL)
panic("_dmamap_load_uio: USERSPACE but no proc");
#endif
}
first = 1;
seg = 0;
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 = (*t->_dmamap_load_buffer)(t, map, addr, minlen,
p, flags, &lastaddr, &seg, first);
first = 0;
resid -= minlen;
}
if (error == 0) {
map->dm_nsegs = seg + 1;
map->dm_mapsize = uio->uio_resid;
}
return (error);
}
/*
* Like _dmamap_load(), but for raw memory allocated with
* bus_dmamem_alloc().
*/
int
_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)
{
if (nsegs > map->_dm_segcnt || size > map->_dm_size)
return (EINVAL);
/*
* Make sure we don't cross any boundaries.
*/
if (map->_dm_boundary) {
bus_addr_t bmask = ~(map->_dm_boundary - 1);
int i;
if (t->_dma_mask != 0)
bmask &= t->_dma_mask;
for (i = 0; i < nsegs; i++) {
if (segs[i].ds_len > map->_dm_maxsegsz)
return (EINVAL);
if ((segs[i].ds_addr & bmask) !=
((segs[i].ds_addr + segs[i].ds_len - 1) & bmask))
return (EINVAL);
}
}
bcopy(segs, map->dm_segs, nsegs * sizeof(*segs));
map->dm_nsegs = nsegs;
map->dm_mapsize = size;
return (0);
}
/*
* Common function for unloading a DMA map. May be called by
* bus-specific DMA map unload functions.
*/
void
_dmamap_unload(bus_dma_tag_t t, bus_dmamap_t map)
{
/*
* No resources to free; just mark the mappings as
* invalid.
*/
map->dm_nsegs = 0;
map->dm_mapsize = 0;
}
/*
* Common function for DMA map synchronization. May be called
* by bus-specific DMA map synchronization functions.
*/
void
_dmamap_sync(bus_dma_tag_t t, bus_dmamap_t map, bus_addr_t addr,
bus_size_t size, int op)
{
int nsegs;
int curseg;
struct cpu_info *ci;
#ifdef TGT_COHERENT
if ((op & BUS_DMASYNC_PREWRITE) == 0)
return;
#endif
ci = curcpu();
nsegs = map->dm_nsegs;
curseg = 0;
while (size && nsegs) {
paddr_t paddr;
vaddr_t vaddr;
bus_size_t ssize;
ssize = map->dm_segs[curseg].ds_len;
paddr = map->dm_segs[curseg]._ds_paddr;
vaddr = map->dm_segs[curseg]._ds_vaddr;
if (addr != 0) {
if (addr >= ssize) {
addr -= ssize;
ssize = 0;
} else {
vaddr += addr;
paddr += addr;
ssize -= addr;
addr = 0;
}
}
if (ssize > size)
ssize = size;
if (IS_XKPHYS(vaddr) && XKPHYS_TO_CCA(vaddr) == CCA_NC) {
size -= ssize;
ssize = 0;
}
if (ssize != 0) {
#ifdef TGT_COHERENT
/* we only need to writeback here */
Mips_IOSyncDCache(ci, vaddr, ssize, CACHE_SYNC_W);
#else
/*
* If only PREWRITE is requested, writeback.
* PREWRITE with PREREAD writebacks
* and invalidates (if noncoherent) *all* cache levels.
* Otherwise, just invalidate (if noncoherent).
*/
if (op & BUS_DMASYNC_PREWRITE) {
if (op & BUS_DMASYNC_PREREAD)
Mips_IOSyncDCache(ci, vaddr,
ssize, CACHE_SYNC_X);
else
Mips_IOSyncDCache(ci, vaddr,
ssize, CACHE_SYNC_W);
} else
if (op & (BUS_DMASYNC_PREREAD | BUS_DMASYNC_POSTREAD)) {
Mips_IOSyncDCache(ci, vaddr,
ssize, CACHE_SYNC_R);
}
#endif
size -= ssize;
}
curseg++;
nsegs--;
}
#ifdef DIAGNOSTIC
if (size != 0)
panic("_dmamap_sync: ran off map!");
#endif
}
/*
* Common function for DMA-safe memory allocation. May be called
* by bus-specific DMA memory allocation functions.
*/
int
_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)
{
return _dmamem_alloc_range(t, size, alignment, boundary,
segs, nsegs, rsegs, flags,
dma_constraint.ucr_low, dma_constraint.ucr_high);
}
/*
* Common function for freeing DMA-safe memory. May be called by
* bus-specific DMA memory free functions.
*/
void
_dmamem_free(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs)
{
vm_page_t 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 = PHYS_TO_VM_PAGE((*t->_device_to_pa)(addr));
TAILQ_INSERT_TAIL(&mlist, m, pageq);
}
}
uvm_pglistfree(&mlist);
}
/*
* Common function for mapping DMA-safe memory. May be called by
* bus-specific DMA memory map functions.
*/
int
_dmamem_map(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs, size_t size,
caddr_t *kvap, int flags)
{
vaddr_t va, sva;
size_t ssize;
paddr_t pa;
bus_addr_t addr;
int curseg, error;
if (nsegs == 1) {
pa = (*t->_device_to_pa)(segs[0].ds_addr);
#ifndef TGT_COHERENT
if (flags & BUS_DMA_COHERENT)
*kvap = (caddr_t)PHYS_TO_XKPHYS(pa, CCA_NC);
else
#endif
*kvap = (caddr_t)PHYS_TO_XKPHYS(pa, CCA_CACHED);
return (0);
}
size = round_page(size);
va = uvm_km_valloc(kernel_map, size);
if (va == 0)
return (ENOMEM);
*kvap = (caddr_t)va;
sva = va;
ssize = size;
for (curseg = 0; curseg < nsegs; curseg++) {
for (addr = segs[curseg].ds_addr;
addr < (segs[curseg].ds_addr + segs[curseg].ds_len);
addr += NBPG, va += NBPG, size -= NBPG) {
#ifdef DIAGNOSTIC
if (size == 0)
panic("_dmamem_map: size botch");
#endif
pa = (*t->_device_to_pa)(addr);
error = pmap_enter(pmap_kernel(), va, pa,
VM_PROT_READ | VM_PROT_WRITE, VM_PROT_READ |
VM_PROT_WRITE | PMAP_WIRED | PMAP_CANFAIL);
if (error) {
pmap_update(pmap_kernel());
uvm_km_free(kernel_map, sva, ssize);
return (error);
}
#ifndef TGT_COHERENT
if (flags & BUS_DMA_COHERENT)
pmap_page_cache(PHYS_TO_VM_PAGE(pa),
PV_UNCACHED);
#endif
}
pmap_update(pmap_kernel());
}
return (0);
}
/*
* Common function for unmapping DMA-safe memory. May be called by
* bus-specific DMA memory unmapping functions.
*/
void
_dmamem_unmap(bus_dma_tag_t t, caddr_t kva, size_t size)
{
if (IS_XKPHYS((vaddr_t)kva))
return;
size = round_page(size);
uvm_km_free(kernel_map, (vaddr_t)kva, size);
}
/*
* Common function for mmap(2)'ing DMA-safe memory. May be called by
* bus-specific DMA mmap(2)'ing functions.
*/
paddr_t
_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 & PAGE_MASK)
panic("_dmamem_mmap: offset unaligned");
if (segs[i].ds_addr & PAGE_MASK)
panic("_dmamem_mmap: segment unaligned");
if (segs[i].ds_len & PAGE_MASK)
panic("_dmamem_mmap: segment size not multiple"
" of page size");
#endif
if (off >= segs[i].ds_len) {
off -= segs[i].ds_len;
continue;
}
return ((*t->_device_to_pa)(segs[i].ds_addr) + off);
}
/* Page not found. */
return (-1);
}
/**********************************************************************
* DMA utility functions
**********************************************************************/
/*
* Utility function to load a linear buffer. lastaddrp holds state
* between invocations (for multiple-buffer loads). segp contains
* the starting segment on entrance, and the ending segment on exit.
* first indicates if this is the first invocation of this function.
*/
int
_dmamap_load_buffer(bus_dma_tag_t t, bus_dmamap_t map, void *buf,
bus_size_t buflen, struct proc *p, int flags, paddr_t *lastaddrp,
int *segp, int first)
{
bus_size_t sgsize;
bus_addr_t lastaddr, baddr, bmask;
paddr_t curaddr;
vaddr_t vaddr = (vaddr_t)buf;
int seg;
pmap_t pmap;
if (p != NULL)
pmap = p->p_vmspace->vm_map.pmap;
else
pmap = pmap_kernel();
lastaddr = *lastaddrp;
bmask = ~(map->_dm_boundary - 1);
if (t->_dma_mask != 0)
bmask &= t->_dma_mask;
for (seg = *segp; buflen > 0; ) {
/*
* Get the physical address for this segment.
*/
if (pmap_extract(pmap, vaddr, &curaddr) == FALSE)
panic("_dmapmap_load_buffer: pmap_extract(%x, %x) failed!",
pmap, vaddr);
#ifdef DIAGNOSTIC
if (curaddr > dma_constraint.ucr_high ||
curaddr < dma_constraint.ucr_low)
panic("Non DMA-reachable buffer at curaddr %p (raw)",
curaddr);
#endif
/*
* Compute the segment size, and adjust counts.
*/
sgsize = NBPG - ((u_long)vaddr & PGOFSET);
if (buflen < sgsize)
sgsize = buflen;
/*
* Make sure we don't cross any boundaries.
*/
if (map->_dm_boundary > 0) {
baddr = ((bus_addr_t)curaddr + map->_dm_boundary) &
bmask;
if (sgsize > (baddr - (bus_addr_t)curaddr))
sgsize = (baddr - (bus_addr_t)curaddr);
}
/*
* Insert chunk into a segment, coalescing with
* previous segment if possible.
*/
if (first) {
map->dm_segs[seg].ds_addr =
(*t->_pa_to_device)(curaddr);
map->dm_segs[seg].ds_len = sgsize;
map->dm_segs[seg]._ds_paddr = curaddr;
map->dm_segs[seg]._ds_vaddr = vaddr;
first = 0;
} else {
if ((bus_addr_t)curaddr == lastaddr + 1 &&
(map->dm_segs[seg].ds_len + sgsize) <=
map->_dm_maxsegsz &&
(map->_dm_boundary == 0 ||
(map->dm_segs[seg].ds_addr & bmask) ==
((bus_addr_t)curaddr & bmask)))
map->dm_segs[seg].ds_len += sgsize;
else {
if (++seg >= map->_dm_segcnt)
break;
map->dm_segs[seg].ds_addr =
(*t->_pa_to_device)(curaddr);
map->dm_segs[seg].ds_len = sgsize;
map->dm_segs[seg]._ds_paddr = curaddr;
map->dm_segs[seg]._ds_vaddr = vaddr;
}
}
lastaddr = (bus_addr_t)curaddr + sgsize - 1;
vaddr += sgsize;
buflen -= sgsize;
}
*segp = seg;
*lastaddrp = lastaddr;
/*
* Did we fit?
*/
if (buflen != 0)
return (EFBIG); /* XXX better return value here? */
return (0);
}
/*
* Allocate physical memory from the given physical address range.
* Called by DMA-safe memory allocation methods.
*/
int
_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, paddr_t low, paddr_t high)
{
vaddr_t curaddr, lastaddr;
vm_page_t m;
struct pglist mlist;
int curseg, error, plaflag;
/* Always round the size. */
size = round_page(size);
/*
* Allocate pages from the VM system.
*/
plaflag = flags & BUS_DMA_NOWAIT ? UVM_PLA_NOWAIT : UVM_PLA_WAITOK;
if (flags & BUS_DMA_ZERO)
plaflag |= UVM_PLA_ZERO;
TAILQ_INIT(&mlist);
error = uvm_pglistalloc(size, low, high, alignment, boundary,
&mlist, nsegs, plaflag);
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 =
(*t->_pa_to_device)(VM_PAGE_TO_PHYS(m));
segs[curseg].ds_len = PAGE_SIZE;
m = TAILQ_NEXT(m, pageq);
for (; m != TAILQ_END(&mlist); m = TAILQ_NEXT(m, pageq)) {
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("_dmamem_alloc_range");
}
#endif
curaddr = (*t->_pa_to_device)(curaddr);
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);
}
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