NetBSD-5.0.2/sys/arch/atari/atari/bus.c
/* $NetBSD: bus.c,v 1.47 2008/06/04 12:41:40 ad Exp $ */
/*-
* Copyright (c) 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 and by Chris G. Demetriou.
*
* 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.c,v 1.47 2008/06/04 12:41:40 ad Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/extent.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/proc.h>
#include <uvm/uvm_extern.h>
#include <machine/cpu.h>
#include <m68k/cacheops.h>
#define _ATARI_BUS_DMA_PRIVATE
#include <machine/bus.h>
int bus_dmamem_alloc_range __P((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,
paddr_t low, paddr_t high));
static int _bus_dmamap_load_buffer __P((bus_dma_tag_t tag, bus_dmamap_t,
void *, bus_size_t, struct vmspace *, int, paddr_t *,
int *, int));
static int bus_mem_add_mapping __P((bus_space_tag_t t, bus_addr_t bpa,
bus_size_t size, int flags, bus_space_handle_t *bsph));
extern struct extent *iomem_ex;
extern int iomem_malloc_safe;
extern paddr_t avail_end;
/*
* We need these for the early memory allocator. The idea is this:
* Allocate VA-space through ptextra (atari_init.c:startc()). When
* The VA & size of this space are known, call bootm_init().
* Until the VM-system is up, bus_mem_add_mapping() allocates it's virtual
* addresses from this extent-map.
*
* This allows for the console code to use the bus_space interface at a
* very early stage of the system configuration.
*/
static pt_entry_t *bootm_ptep;
static long bootm_ex_storage[EXTENT_FIXED_STORAGE_SIZE(32) /
sizeof(long)];
static struct extent *bootm_ex;
void bootm_init(vaddr_t, pt_entry_t *, u_long);
static vaddr_t bootm_alloc(paddr_t pa, u_long size, int flags);
static int bootm_free(vaddr_t va, u_long size);
void
bootm_init(va, ptep, size)
vaddr_t va;
pt_entry_t *ptep;
u_long size;
{
bootm_ex = extent_create("bootmem", va, va + size, M_DEVBUF,
(void *)bootm_ex_storage, sizeof(bootm_ex_storage),
EX_NOCOALESCE|EX_NOWAIT);
bootm_ptep = ptep;
}
vaddr_t
bootm_alloc(pa, size, flags)
paddr_t pa;
u_long size;
int flags;
{
pt_entry_t *pg, *epg;
pt_entry_t pg_proto;
vaddr_t va, rva;
if (extent_alloc(bootm_ex, size, PAGE_SIZE, 0, EX_NOWAIT, &rva)) {
printf("bootm_alloc fails! Not enough fixed extents?\n");
printf("Requested extent: pa=%lx, size=%lx\n",
(u_long)pa, size);
return 0;
}
pg = &bootm_ptep[btoc(rva - bootm_ex->ex_start)];
epg = &pg[btoc(size)];
va = rva;
pg_proto = pa | PG_RW | PG_V;
if (!(flags & BUS_SPACE_MAP_CACHEABLE))
pg_proto |= PG_CI;
while(pg < epg) {
*pg++ = pg_proto;
pg_proto += PAGE_SIZE;
#if defined(M68040) || defined(M68060)
if (mmutype == MMU_68040) {
DCFP(pa);
pa += PAGE_SIZE;
}
#endif
TBIS(va);
va += PAGE_SIZE;
}
return rva;
}
int
bootm_free(va, size)
vaddr_t va;
u_long size;
{
if ((va < bootm_ex->ex_start) || ((va + size) > bootm_ex->ex_end))
return 0; /* Not for us! */
extent_free(bootm_ex, va, size, EX_NOWAIT);
return 1;
}
int
bus_space_map(t, bpa, size, flags, mhp)
bus_space_tag_t t;
bus_addr_t bpa;
bus_size_t size;
int flags;
bus_space_handle_t *mhp;
{
int error;
/*
* Before we go any further, let's make sure that this
* region is available.
*/
error = extent_alloc_region(iomem_ex, bpa + t->base, size,
EX_NOWAIT | (iomem_malloc_safe ? EX_MALLOCOK : 0));
if (error)
return (error);
error = bus_mem_add_mapping(t, bpa, size, flags, mhp);
if (error) {
if (extent_free(iomem_ex, bpa + t->base, size, EX_NOWAIT |
(iomem_malloc_safe ? EX_MALLOCOK : 0))) {
printf("bus_space_map: pa 0x%lx, size 0x%lx\n", bpa, size);
printf("bus_space_map: can't free region\n");
}
}
return (error);
}
int
bus_space_alloc(t, rstart, rend, size, alignment, boundary, flags, bpap, bshp)
bus_space_tag_t t;
bus_addr_t rstart, rend;
bus_size_t size, alignment, boundary;
int flags;
bus_addr_t *bpap;
bus_space_handle_t *bshp;
{
u_long bpa;
int error;
#ifdef DIAGNOSTIC
/*
* Sanity check the allocation against the extent's boundaries.
* XXX: Since we manage the whole of memory in a single map,
* this is nonsense for now! Brace it DIAGNOSTIC....
*/
if ((rstart + t->base) < iomem_ex->ex_start
|| (rend + t->base) > iomem_ex->ex_end)
panic("bus_space_alloc: bad region start/end");
#endif /* DIAGNOSTIC */
/*
* Do the requested allocation.
*/
error = extent_alloc_subregion(iomem_ex, rstart + t->base,
rend + t->base, size, alignment, boundary,
EX_FAST | EX_NOWAIT | (iomem_malloc_safe ? EX_MALLOCOK : 0),
&bpa);
if (error)
return (error);
/*
* Map the bus physical address to a kernel virtual address.
*/
error = bus_mem_add_mapping(t, bpa, size, flags, bshp);
if (error) {
if (extent_free(iomem_ex, bpa, size, EX_NOWAIT |
(iomem_malloc_safe ? EX_MALLOCOK : 0))) {
printf("bus_space_alloc: pa 0x%lx, size 0x%lx\n",
bpa, size);
printf("bus_space_alloc: can't free region\n");
}
}
*bpap = bpa;
return (error);
}
static int
bus_mem_add_mapping(t, bpa, size, flags, bshp)
bus_space_tag_t t;
bus_addr_t bpa;
bus_size_t size;
int flags;
bus_space_handle_t *bshp;
{
vaddr_t va;
paddr_t pa, endpa;
pa = m68k_trunc_page(bpa + t->base);
endpa = m68k_round_page((bpa + t->base + size) - 1);
#ifdef DIAGNOSTIC
if (endpa <= pa)
panic("bus_mem_add_mapping: overflow");
#endif
if (kernel_map == NULL) {
/*
* The VM-system is not yet operational, allocate from
* a special pool.
*/
va = bootm_alloc(pa, endpa - pa, flags);
if (va == 0)
return (ENOMEM);
*bshp = va + (bpa & PGOFSET);
return (0);
}
va = uvm_km_alloc(kernel_map, endpa - pa, 0,
UVM_KMF_VAONLY | UVM_KMF_NOWAIT);
if (va == 0)
return (ENOMEM);
*bshp = va + (bpa & PGOFSET);
for(; pa < endpa; pa += PAGE_SIZE, va += PAGE_SIZE) {
u_int *ptep, npte;
pmap_enter(pmap_kernel(), (vaddr_t)va, pa,
VM_PROT_READ|VM_PROT_WRITE, PMAP_WIRED);
ptep = kvtopte(va);
npte = *ptep & ~PG_CMASK;
if (!(flags & BUS_SPACE_MAP_CACHEABLE))
npte |= PG_CI;
else if (mmutype == MMU_68040)
npte |= PG_CCB;
*ptep = npte;
}
pmap_update(pmap_kernel());
TBIAS();
return (0);
}
void
bus_space_unmap(t, bsh, size)
bus_space_tag_t t;
bus_space_handle_t bsh;
bus_size_t size;
{
vaddr_t va, endva;
paddr_t bpa;
va = m68k_trunc_page(bsh);
endva = m68k_round_page(((char *)bsh + size) - 1);
#ifdef DIAGNOSTIC
if (endva < va)
panic("unmap_iospace: overflow");
#endif
(void) pmap_extract(pmap_kernel(), va, &bpa);
bpa += ((u_long)bsh & PGOFSET);
/*
* Free the kernel virtual mapping.
*/
if (!bootm_free(va, endva - va)) {
pmap_remove(pmap_kernel(), va, endva);
pmap_update(pmap_kernel());
uvm_km_free(kernel_map, va, endva - va, UVM_KMF_VAONLY);
}
/*
* Mark as free in the extent map.
*/
if (extent_free(iomem_ex, bpa, size,
EX_NOWAIT | (iomem_malloc_safe ? EX_MALLOCOK : 0))) {
printf("bus_space_unmap: pa 0x%lx, size 0x%lx\n", bpa, size);
printf("bus_space_unmap: can't free region\n");
}
}
/*
* Get a new handle for a subregion of an already-mapped area of bus space.
*/
int bus_space_subregion(t, memh, off, sz, mhp)
bus_space_tag_t t;
bus_space_handle_t memh;
bus_size_t off, sz;
bus_space_handle_t *mhp;
{
*mhp = memh + off;
return 0;
}
paddr_t
bus_space_mmap(t, addr, off, prot, flags)
bus_space_tag_t t;
bus_addr_t addr;
off_t off;
int prot;
int flags;
{
/*
* "addr" is the base address of the device we're mapping.
* "off" is the offset into that device.
*
* Note we are called for each "page" in the device that
* the upper layers want to map.
*/
return (m68k_btop(addr + off));
}
/*
* Common function for DMA map creation. May be called by bus-specific
* DMA map creation functions.
*/
int
_bus_dmamap_create(t, size, nsegments, maxsegsz, boundary, flags, dmamp)
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 atari_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 atari_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);
bzero(mapstore, mapsize);
map = (struct atari_bus_dmamap *)mapstore;
map->_dm_size = size;
map->_dm_segcnt = nsegments;
map->_dm_maxmaxsegsz = maxsegsz;
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;
*dmamp = map;
return (0);
}
/*
* Common function for DMA map destruction. May be called by bus-specific
* DMA map destruction functions.
*/
void
_bus_dmamap_destroy(t, map)
bus_dma_tag_t t;
bus_dmamap_t map;
{
free(map, M_DMAMAP);
}
/*
* Common function for loading a DMA map with a linear buffer. May
* be called by bus-specific DMA map load functions.
*/
int
_bus_dmamap_load(t, map, buf, buflen, p, flags)
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);
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(t, map, buf, buflen, vm, flags,
&lastaddr, &seg, 1);
if (error == 0) {
map->dm_mapsize = buflen;
map->dm_nsegs = seg + 1;
}
return (error);
}
/*
* Like _bus_dmamap_load(), but for mbufs.
*/
int
_bus_dmamap_load_mbuf(t, map, m0, flags)
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);
#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) {
if (m->m_len == 0)
continue;
error = _bus_dmamap_load_buffer(t, map, m->m_data, m->m_len,
vmspace_kernel(), flags, &lastaddr, &seg, first);
first = 0;
}
if (error == 0) {
map->dm_mapsize = m0->m_pkthdr.len;
map->dm_nsegs = seg + 1;
}
return (error);
}
/*
* Like _bus_dmamap_load(), but for uios.
*/
int
_bus_dmamap_load_uio(t, map, uio, flags)
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 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);
resid = uio->uio_resid;
iov = uio->uio_iov;
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(t, map, addr, minlen,
uio->uio_vmspace, flags, &lastaddr, &seg, first);
first = 0;
resid -= minlen;
}
if (error == 0) {
map->dm_mapsize = uio->uio_resid;
map->dm_nsegs = seg + 1;
}
return (error);
}
/*
* Like _bus_dmamap_load(), but for raw memory allocated with
* bus_dmamem_alloc().
*/
int
_bus_dmamap_load_raw(t, map, segs, nsegs, size, flags)
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");
}
/*
* Common function for unloading a DMA map. May be called by
* bus-specific DMA map unload functions.
*/
void
_bus_dmamap_unload(t, map)
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;
}
/*
* Common function for DMA map synchronization. May be called
* by bus-specific DMA map synchronization functions.
*/
void
_bus_dmamap_sync(t, map, off, len, ops)
bus_dma_tag_t t;
bus_dmamap_t map;
bus_addr_t off;
bus_size_t len;
int ops;
{
#if defined(M68040) || defined(M68060)
int i, pa_off, inc, seglen;
u_long pa, end_pa;
pa_off = t->_displacement;
/* Flush granularity */
inc = (len > 1024) ? PAGE_SIZE : 16;
for (i = 0; i < map->dm_nsegs && len > 0; i++) {
if (map->dm_segs[i].ds_len <= off) {
/* Segment irrelevant - before requested offset */
off -= map->dm_segs[i].ds_len;
continue;
}
seglen = map->dm_segs[i].ds_len - off;
if (seglen > len)
seglen = len;
len -= seglen;
pa = map->dm_segs[i].ds_addr + off - pa_off;
end_pa = pa + seglen;
if (inc == 16) {
pa &= ~15;
while (pa < end_pa) {
DCFL(pa);
pa += 16;
}
} else {
pa &= ~PGOFSET;
while (pa < end_pa) {
DCFP(pa);
pa += PAGE_SIZE;
}
}
}
#endif
}
/*
* Common function for DMA-safe memory allocation. May be called
* by bus-specific DMA memory allocation functions.
*/
int
bus_dmamem_alloc(t, size, alignment, boundary, segs, nsegs, rsegs, flags)
bus_dma_tag_t t;
bus_size_t size, alignment, 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)));
}
/*
* Common function for freeing DMA-safe memory. May be called by
* bus-specific DMA memory free functions.
*/
void
bus_dmamem_free(t, segs, nsegs)
bus_dma_tag_t t;
bus_dma_segment_t *segs;
int nsegs;
{
struct vm_page *m;
bus_addr_t addr, offset;
struct pglist mlist;
int curseg;
offset = t->_displacement;
/*
* 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(addr - offset);
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.
*/
int
bus_dmamem_map(t, segs, nsegs, size, kvap, flags)
bus_dma_tag_t t;
bus_dma_segment_t *segs;
int nsegs;
size_t size;
void **kvap;
int flags;
{
vaddr_t va;
bus_addr_t addr, offset;
int curseg;
const uvm_flag_t kmflags =
(flags & BUS_DMA_NOWAIT) != 0 ? UVM_KMF_NOWAIT : 0;
offset = t->_displacement;
size = round_page(size);
va = uvm_km_alloc(kernel_map, size, 0, UVM_KMF_VAONLY | kmflags);
if (va == 0)
return (ENOMEM);
*kvap = (void *)va;
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");
pmap_enter(pmap_kernel(), va, addr - offset,
VM_PROT_READ | VM_PROT_WRITE,
VM_PROT_READ | VM_PROT_WRITE | PMAP_WIRED);
}
}
pmap_update(pmap_kernel());
return (0);
}
/*
* Common function for unmapping DMA-safe memory. May be called by
* bus-specific DMA memory unmapping functions.
*/
void
bus_dmamem_unmap(t, kva, size)
bus_dma_tag_t t;
void *kva;
size_t size;
{
#ifdef DIAGNOSTIC
if ((u_long)kva & PGOFSET)
panic("_bus_dmamem_unmap");
#endif
size = round_page(size);
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 functin for mmap(2)'ing DMA-safe memory. May be called by
* bus-specific DMA mmap(2)'ing functions.
*/
paddr_t
bus_dmamem_mmap(t, segs, nsegs, off, prot, flags)
bus_dma_tag_t t;
bus_dma_segment_t *segs;
int nsegs;
off_t off;
int prot, flags;
{
int i, offset;
offset = t->_displacement;
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 (m68k_btop((char *)segs[i].ds_addr - offset + 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 entrace, and the ending segment on exit.
* first indicates if this is the first invocation of this function.
*/
static int
_bus_dmamap_load_buffer(t, map, buf, buflen, vm, flags, lastaddrp, segp, first)
bus_dma_tag_t t;
bus_dmamap_t map;
void *buf;
bus_size_t buflen;
struct vmspace *vm;
int flags;
paddr_t *lastaddrp;
int *segp;
int first;
{
bus_size_t sgsize;
bus_addr_t curaddr, lastaddr, offset, baddr, bmask;
vaddr_t vaddr = (vaddr_t)buf;
int seg;
pmap_t pmap;
offset = t->_displacement;
pmap = vm_map_pmap(&vm->vm_map);
lastaddr = *lastaddrp;
bmask = ~(map->_dm_boundary - 1);
for (seg = *segp; buflen > 0 ; ) {
/*
* Get the physical address for this segment.
*/
(void) pmap_extract(pmap, vaddr, &curaddr);
/*
* Compute the segment size, and adjust counts.
*/
sgsize = PAGE_SIZE - ((u_long)vaddr & PGOFSET);
if (buflen < sgsize)
sgsize = buflen;
/*
* 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
* previous segment if possible.
*/
if (first) {
map->dm_segs[seg].ds_addr = curaddr + offset;
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_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 + offset;
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.
*/
int
bus_dmamem_alloc_range(t, size, alignment, boundary, segs, nsegs, rsegs,
flags, low, high)
bus_dma_tag_t t;
bus_size_t size, alignment, boundary;
bus_dma_segment_t *segs;
int nsegs;
int *rsegs;
int flags;
paddr_t low;
paddr_t high;
{
paddr_t curaddr, lastaddr;
bus_addr_t offset;
struct vm_page *m;
struct pglist mlist;
int curseg, error;
offset = t->_displacement;
/* 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 = mlist.tqh_first;
curseg = 0;
lastaddr = VM_PAGE_TO_PHYS(m);
segs[curseg].ds_addr = lastaddr + offset;
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("uvm_pglistalloc 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 + offset;
segs[curseg].ds_len = PAGE_SIZE;
}
lastaddr = curaddr;
}
*rsegs = curseg + 1;
return (0);
}