/* $NetBSD: bus_dma.c,v 1.74 2022/07/26 20:08:54 andvar Exp $ */
/*-
* Copyright (c) 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/cdefs.h> /* RCS ID & Copyright macro defns */
__KERNEL_RCSID(0, "$NetBSD: bus_dma.c,v 1.74 2022/07/26 20:08:54 andvar Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/device.h>
#include <sys/kmem.h>
#include <sys/proc.h>
#include <sys/mbuf.h>
#include <uvm/uvm_extern.h>
#define _ALPHA_BUS_DMA_PRIVATE
#include <sys/bus.h>
#include <machine/intr.h>
#include <dev/bus_dma/bus_dmamem_common.h>
static int _bus_dmamap_load_buffer_direct(bus_dma_tag_t,
bus_dmamap_t, void *, bus_size_t, struct vmspace *, int,
paddr_t *, int *, int);
extern paddr_t avail_start, avail_end; /* from pmap.c */
#define DMA_COUNT_DECL(cnt) _DMA_COUNT_DECL(dma_direct, cnt)
#define DMA_COUNT(cnt) _DMA_COUNT(dma_direct, cnt)
static size_t
_bus_dmamap_mapsize(int const nsegments)
{
KASSERT(nsegments > 0);
return sizeof(struct alpha_bus_dmamap) +
(sizeof(bus_dma_segment_t) * (nsegments - 1));
}
/*
* Common function for DMA map creation. May be called by bus-specific
* DMA map creation functions.
*/
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 alpha_bus_dmamap *map;
void *mapstore;
/*
* 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).
*/
if ((mapstore = kmem_zalloc(_bus_dmamap_mapsize(nsegments),
(flags & BUS_DMA_NOWAIT) ? KM_NOSLEEP : KM_SLEEP)) == NULL)
return (ENOMEM);
map = (struct alpha_bus_dmamap *)mapstore;
map->_dm_size = size;
map->_dm_segcnt = nsegments;
map->_dm_maxmaxsegsz = maxsegsz;
if (t->_boundary != 0 && t->_boundary < boundary)
map->_dm_boundary = t->_boundary;
else
map->_dm_boundary = boundary;
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;
map->_dm_window = NULL;
*dmamp = map;
return (0);
}
/*
* Common function for DMA map destruction. May be called by bus-specific
* DMA map destruction functions.
*/
void
_bus_dmamap_destroy(bus_dma_tag_t t, bus_dmamap_t map)
{
kmem_free(map, _bus_dmamap_mapsize(map->_dm_segcnt));
}
/*
* 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.
*/
static int
_bus_dmamap_load_buffer_direct(bus_dma_tag_t t, bus_dmamap_t map,
void *buf, size_t buflen, struct vmspace *vm, int flags, paddr_t *lastaddrp,
int *segp, int first)
{
bus_size_t sgsize;
bus_addr_t curaddr, lastaddr, baddr, bmask;
vaddr_t vaddr = (vaddr_t)buf;
int seg;
bool address_is_valid __diagused;
lastaddr = *lastaddrp;
bmask = ~(map->_dm_boundary - 1);
for (seg = *segp; buflen > 0 ; ) {
/*
* Get the physical address for this segment.
*/
address_is_valid =
pmap_extract(vm->vm_map.pmap, vaddr, &curaddr);
KASSERT(address_is_valid);
/*
* If we're beyond the current DMA window, indicate
* that and try to fall back into SGMAPs.
*/
if (t->_wsize != 0 && curaddr >= t->_wsize)
return (EINVAL);
curaddr |= t->_wbase;
/*
* Compute the segment size, and adjust counts.
*/
sgsize = PAGE_SIZE - ((u_long)vaddr & PGOFSET);
if (buflen < sgsize)
sgsize = buflen;
if (map->dm_maxsegsz < sgsize)
sgsize = map->dm_maxsegsz;
/*
* Make sure we don't cross any boundaries.
*/
if (map->_dm_boundary > 0) {
baddr = (curaddr + map->_dm_boundary) & bmask;
if (sgsize > (baddr - curaddr))
sgsize = (baddr - curaddr);
}
/*
* Insert chunk into a segment, coalescing with
* the previous segment if possible.
*/
if (first) {
map->dm_segs[seg].ds_addr = curaddr;
map->dm_segs[seg].ds_len = sgsize;
first = 0;
} else {
if ((map->_dm_flags & DMAMAP_NO_COALESCE) == 0 &&
curaddr == lastaddr &&
(map->dm_segs[seg].ds_len + sgsize) <=
map->dm_maxsegsz &&
(map->_dm_boundary == 0 ||
(map->dm_segs[seg].ds_addr & bmask) ==
(curaddr & bmask)))
map->dm_segs[seg].ds_len += sgsize;
else {
if (++seg >= map->_dm_segcnt)
break;
map->dm_segs[seg].ds_addr = curaddr;
map->dm_segs[seg].ds_len = sgsize;
}
}
lastaddr = curaddr + sgsize;
vaddr += sgsize;
buflen -= sgsize;
}
*segp = seg;
*lastaddrp = lastaddr;
/*
* Did we fit?
*/
if (buflen != 0) {
/*
* If there is a chained window, we will automatically
* fall back to it.
*/
return (EFBIG); /* XXX better return value here? */
}
return (0);
}
DMA_COUNT_DECL(load);
DMA_COUNT_DECL(load_next_window);
/*
* Common function for loading a direct-mapped DMA map with a linear
* buffer. Called by bus-specific DMA map load functions with the
* OR value appropriate for indicating "direct-mapped" for that
* chipset.
*/
int
_bus_dmamap_load_direct(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;
struct vmspace *vm;
/*
* 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);
KASSERT((map->_dm_flags & (BUS_DMA_READ|BUS_DMA_WRITE)) == 0);
if (buflen > map->_dm_size)
return (EINVAL);
if (p != NULL) {
vm = p->p_vmspace;
} else {
vm = vmspace_kernel();
}
seg = 0;
error = _bus_dmamap_load_buffer_direct(t, map, buf, buflen,
vm, flags, &lastaddr, &seg, 1);
if (error == 0) {
DMA_COUNT(load);
map->dm_mapsize = buflen;
map->dm_nsegs = seg + 1;
map->_dm_window = t;
} else if (t->_next_window != NULL) {
/*
* Give the next window a chance.
*/
DMA_COUNT(load_next_window);
error = bus_dmamap_load(t->_next_window, map, buf, buflen,
p, flags);
}
return (error);
}
DMA_COUNT_DECL(load_mbuf);
DMA_COUNT_DECL(load_mbuf_next_window);
/*
* Like _bus_dmamap_load_direct(), but for mbufs.
*/
int
_bus_dmamap_load_mbuf_direct(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_mapsize = 0;
map->dm_nsegs = 0;
KASSERT(map->dm_maxsegsz <= map->_dm_maxmaxsegsz);
KASSERT((map->_dm_flags & (BUS_DMA_READ|BUS_DMA_WRITE)) == 0);
#ifdef DIAGNOSTIC
if ((m0->m_flags & M_PKTHDR) == 0)
panic("_bus_dmamap_load_mbuf_direct: 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;
/* XXX Could be better about coalescing. */
/* XXX Doesn't check boundaries. */
switch (m->m_flags & (M_EXT|M_EXT_CLUSTER)) {
case M_EXT|M_EXT_CLUSTER:
/* XXX KDASSERT */
KASSERT(m->m_ext.ext_paddr != M_PADDR_INVALID);
lastaddr = m->m_ext.ext_paddr +
(m->m_data - m->m_ext.ext_buf);
have_addr:
if (first == 0 &&
++seg >= map->_dm_segcnt) {
error = EFBIG;
break;
}
/*
* If we're beyond the current DMA window, indicate
* that and try to fall back into SGMAPs.
*/
if (t->_wsize != 0 && lastaddr >= t->_wsize) {
error = EINVAL;
break;
}
lastaddr |= t->_wbase;
map->dm_segs[seg].ds_addr = lastaddr;
map->dm_segs[seg].ds_len = m->m_len;
lastaddr += m->m_len;
break;
case 0:
lastaddr = m->m_paddr + M_BUFOFFSET(m) +
(m->m_data - M_BUFADDR(m));
goto have_addr;
default:
error = _bus_dmamap_load_buffer_direct(t, map,
m->m_data, m->m_len, vmspace_kernel(), flags,
&lastaddr, &seg, first);
}
first = 0;
}
if (error == 0) {
DMA_COUNT(load_mbuf);
map->dm_mapsize = m0->m_pkthdr.len;
map->dm_nsegs = seg + 1;
map->_dm_window = t;
} else if (t->_next_window != NULL) {
/*
* Give the next window a chance.
*/
DMA_COUNT(load_mbuf_next_window);
error = bus_dmamap_load_mbuf(t->_next_window, map, m0, flags);
}
return (error);
}
DMA_COUNT_DECL(load_uio);
DMA_COUNT_DECL(load_uio_next_window);
/*
* Like _bus_dmamap_load_direct(), but for uios.
*/
int
_bus_dmamap_load_uio_direct(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 vmspace *vm;
struct iovec *iov;
void *addr;
/*
* 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);
KASSERT((map->_dm_flags & (BUS_DMA_READ|BUS_DMA_WRITE)) == 0);
resid = uio->uio_resid;
iov = uio->uio_iov;
vm = uio->uio_vmspace;
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 = _bus_dmamap_load_buffer_direct(t, map,
addr, minlen, vm, flags, &lastaddr, &seg, first);
first = 0;
resid -= minlen;
}
if (error == 0) {
DMA_COUNT(load_uio);
map->dm_mapsize = uio->uio_resid;
map->dm_nsegs = seg + 1;
map->_dm_window = t;
} else if (t->_next_window != NULL) {
/*
* Give the next window a chance.
*/
DMA_COUNT(load_uio_next_window);
error = bus_dmamap_load_uio(t->_next_window, map, uio, flags);
}
return (error);
}
/*
* Like _bus_dmamap_load_direct(), but for raw memory.
*/
int
_bus_dmamap_load_raw_direct(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_direct: not implemented");
}
/*
* Common function for unloading a DMA map. May be called by
* chipset-specific DMA map unload functions.
*/
void
_bus_dmamap_unload_common(bus_dma_tag_t t, bus_dmamap_t map)
{
/*
* No resources to free; just mark the mappings as
* invalid.
*/
map->dm_maxsegsz = map->_dm_maxmaxsegsz;
map->dm_mapsize = 0;
map->dm_nsegs = 0;
map->_dm_window = NULL;
map->_dm_flags &= ~(BUS_DMA_READ|BUS_DMA_WRITE);
}
DMA_COUNT_DECL(unload);
void
_bus_dmamap_unload(bus_dma_tag_t t, bus_dmamap_t map)
{
KASSERT(map->_dm_window == t);
DMA_COUNT(unload);
_bus_dmamap_unload_common(t, map);
}
/*
* Common function for DMA map synchronization. May be called
* by chipset-specific DMA map synchronization functions.
*/
void
_bus_dmamap_sync(bus_dma_tag_t t, bus_dmamap_t map, bus_addr_t offset,
bus_size_t len, int ops)
{
alpha_mb();
}
/*
* Common function for DMA-safe memory allocation. May be called
* by bus-specific DMA memory allocation functions.
*/
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)
{
return (_bus_dmamem_alloc_range(t, size, alignment, boundary,
segs, nsegs, rsegs, flags, 0, trunc_page(avail_end)));
}
/*
* 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, paddr_t low, paddr_t high)
{
return (_bus_dmamem_alloc_range_common(t, size, alignment, boundary,
segs, nsegs, rsegs, flags,
low, high));
}
/*
* 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)
{
_bus_dmamem_free_common(t, segs, nsegs);
}
/*
* Common function for mapping DMA-safe memory. May be called by
* bus-specific DMA memory map functions.
*/
int
_bus_dmamem_map(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs,
size_t size, void **kvap, int flags)
{
/*
* If we're only mapping 1 segment, use K0SEG, to avoid
* TLB thrashing.
*/
if (nsegs == 1) {
*kvap = (void *)ALPHA_PHYS_TO_K0SEG(segs[0].ds_addr);
return (0);
}
return (_bus_dmamem_map_common(t, segs, nsegs, size, kvap, flags, 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)
{
/*
* Nothing to do if we mapped it with K0SEG.
*/
if (kva >= (void *)ALPHA_K0SEG_BASE &&
kva <= (void *)ALPHA_K0SEG_END)
return;
_bus_dmamem_unmap_common(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
_bus_dmamem_mmap(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs,
off_t off, int prot, int flags)
{
bus_addr_t rv;
rv = _bus_dmamem_mmap_common(t, segs, nsegs, off, prot, flags);
if (rv == (bus_addr_t)-1)
return (-1);
return (alpha_btop((char *)rv));
}