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Implement bus_dmamap_load_mbuf().

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This commit is contained in:
thorpej 1998-01-27 03:31:54 +00:00
parent 5ac7e550d1
commit 5d3fc3e8bc
1 changed files with 121 additions and 66 deletions
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187
sys/arch/i386/i386/machdep.c
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@ -1,7 +1,7 @@
/* $NetBSD: machdep.c,v 1.276 1998/01/24 13:19:50 mycroft Exp $ */
/* $NetBSD: machdep.c,v 1.277 1998/01/27 03:31:54 thorpej Exp $ */
/*-
* Copyright (c) 1996, 1997 The NetBSD Foundation, Inc.
* Copyright (c) 1996, 1997, 1998 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
@ -310,6 +310,9 @@ static int exec_nomid __P((struct proc *, struct exec_package *));
int i386_mem_add_mapping __P((bus_addr_t, bus_size_t,
int, bus_space_handle_t *));
int _bus_dmamap_load_buffer __P((bus_dmamap_t, void *, bus_size_t,
struct proc *, int, vm_offset_t *, int *, int));
void cyrix6x86_cpu_setup __P((void));
static __inline u_char
@ -2293,11 +2296,8 @@ _bus_dmamap_load(t, map, buf, buflen, p, flags)
struct proc *p;
int flags;
{
bus_size_t sgsize;
bus_addr_t curaddr, lastaddr;
caddr_t vaddr = buf;
int first, seg;
pmap_t pmap;
vm_offset_t lastaddr;
int seg, error;
/*
* Make sure that on error condition we return "no valid mappings".
@ -2307,76 +2307,52 @@ _bus_dmamap_load(t, map, buf, buflen, p, flags)
if (buflen > map->_dm_size)
return (EINVAL);
/*
* XXX Need to implement "don't dma across this boundry".
*/
if (p != NULL)
pmap = p->p_vmspace->vm_map.pmap;
else
pmap = pmap_kernel();
lastaddr = ~0; /* XXX gcc */
for (first = 1, seg = 0; buflen > 0 && seg < map->_dm_segcnt; ) {
/*
* Get the physical address for this segment.
*/
curaddr = (bus_addr_t)pmap_extract(pmap, (vm_offset_t)vaddr);
/*
* Compute the segment size, and adjust counts.
*/
sgsize = NBPG - ((u_long)vaddr & PGOFSET);
if (buflen < sgsize)
sgsize = buflen;
/*
* Insert chunk into a segment, coalescing with
* previous segment if possible.
*/
if (first) {
map->dm_segs[seg].ds_addr = curaddr;
map->dm_segs[seg].ds_len = sgsize;
first = 0;
} else {
if (curaddr == lastaddr &&
(map->dm_segs[seg].ds_len + sgsize) <=
map->_dm_maxsegsz)
map->dm_segs[seg].ds_len += sgsize;
else {
seg++;
map->dm_segs[seg].ds_addr = curaddr;
map->dm_segs[seg].ds_len = sgsize;
}
}
lastaddr = curaddr + sgsize;
vaddr += sgsize;
buflen -= sgsize;
}
/*
* Did we fit?
*/
if (buflen != 0)
return (EFBIG); /* XXX better return value here? */
map->dm_nsegs = seg + 1;
return (0);
seg = 0;
error = _bus_dmamap_load_buffer(map, buf, buflen, p, flags,
&lastaddr, &seg, 1);
if (error == 0)
map->dm_nsegs = seg + 1;
return (error);
}
/*
* Like _bus_dmamap_load(), but for mbufs.
*/
int
_bus_dmamap_load_mbuf(t, map, m, flags)
_bus_dmamap_load_mbuf(t, map, m0, flags)
bus_dma_tag_t t;
bus_dmamap_t map;
struct mbuf *m;
struct mbuf *m0;
int flags;
{
vm_offset_t lastaddr;
int seg, error, first;
struct mbuf *m;
panic("_bus_dmamap_load: not implemented");
/*
* Make sure that on error condition we return "no valid mappings."
*/
map->dm_nsegs = 0;
#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);
first = 1;
seg = 0;
error = 0;
for (m = m0; m != NULL && error == 0; m = m->m_next) {
error = _bus_dmamap_load_buffer(map, m->m_data, m->m_len,
NULL, flags, &lastaddr, &seg, first);
first = 0;
}
if (error == 0)
map->dm_nsegs = seg + 1;
return (error);
}
/*
@ -2601,6 +2577,85 @@ _bus_dmamem_mmap(t, segs, nsegs, off, prot, flags)
* 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 entrace, and the ending segment on exit.
* first indicates if this is the first invocation of this function.
*/
int
_bus_dmamap_load_buffer(map, buf, buflen, p, flags, lastaddrp, segp, first)
bus_dmamap_t map;
void *buf;
bus_size_t buflen;
struct proc *p;
int flags;
vm_offset_t *lastaddrp;
int *segp;
int first;
{
bus_size_t sgsize;
bus_addr_t curaddr, lastaddr;
caddr_t vaddr = buf;
int seg;
pmap_t pmap;
if (p != NULL)
pmap = p->p_vmspace->vm_map.pmap;
else
pmap = pmap_kernel();
lastaddr = *lastaddrp;
for (seg = *segp; buflen > 0 && seg < map->_dm_segcnt; ) {
/*
* Get the physical address for this segment.
*/
curaddr = (bus_addr_t)pmap_extract(pmap, (vm_offset_t)vaddr);
/*
* Compute the segment size, and adjust counts.
*/
sgsize = NBPG - ((u_long)vaddr & PGOFSET);
if (buflen < sgsize)
sgsize = buflen;
/*
* Insert chunk into a segment, coalescing with
* previous segment if possible.
*/
if (first) {
map->dm_segs[seg].ds_addr = curaddr;
map->dm_segs[seg].ds_len = sgsize;
first = 0;
} else {
if (curaddr == lastaddr &&
(map->dm_segs[seg].ds_len + sgsize) <=
map->_dm_maxsegsz)
map->dm_segs[seg].ds_len += sgsize;
else {
seg++;
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)
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.