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On arm64 always create a bus_dmamap_t object. This will be use to hold the

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list of memory that the kernel will need to sync when operating with a
non-cache coherent DMA engine.

Obtained from:	ABT Systems Ltd
Sponsored by:	The FreeBSD Foundation
This commit is contained in:
andrew 2016-05-11 16:53:41 +00:00
parent 027fd46f7c
commit 4ec608a6fe
1 changed files with 72 additions and 44 deletions
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116
sys/arm64/arm64/busdma_bounce.c
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@ -122,11 +122,13 @@ struct bus_dmamap {
bus_dmamap_callback_t *callback;
void *callback_arg;
STAILQ_ENTRY(bus_dmamap) links;
u_int flags;
#define DMAMAP_COULD_BOUNCE (1 << 0)
#define DMAMAP_FROM_DMAMEM (1 << 1)
};
static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
static struct bus_dmamap nobounce_dmamap;
static void init_bounce_pages(void *dummy);
static int alloc_bounce_zone(bus_dma_tag_t dmat);
@ -248,6 +250,21 @@ bounce_bus_dma_tag_destroy(bus_dma_tag_t dmat)
return (error);
}
static bus_dmamap_t
alloc_dmamap(int flags)
{
bus_dmamap_t map;
map = malloc(sizeof(*map), M_DEVBUF, flags | M_ZERO);
if (map == NULL)
return (NULL);
/* Initialize the new map */
STAILQ_INIT(&map->bpages);
return (map);
}
/*
* Allocate a handle for mapping from kva/uva/physical
* address space into bus device space.
@ -271,6 +288,13 @@ bounce_bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
}
}
*mapp = alloc_dmamap(M_NOWAIT);
if (*mapp == NULL) {
CTR3(KTR_BUSDMA, "%s: tag %p error %d",
__func__, dmat, ENOMEM);
return (ENOMEM);
}
/*
* Bouncing might be required if the driver asks for an active
* exclusion region, a data alignment that is stricter than 1, and/or
@ -279,21 +303,14 @@ bounce_bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
if (dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) {
/* Must bounce */
if (dmat->bounce_zone == NULL) {
if ((error = alloc_bounce_zone(dmat)) != 0)
if ((error = alloc_bounce_zone(dmat)) != 0) {
free(*mapp, M_DEVBUF);
return (error);
}
}
bz = dmat->bounce_zone;
*mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF,
M_NOWAIT | M_ZERO);
if (*mapp == NULL) {
CTR3(KTR_BUSDMA, "%s: tag %p error %d",
__func__, dmat, ENOMEM);
return (ENOMEM);
}
/* Initialize the new map */
STAILQ_INIT(&((*mapp)->bpages));
(*mapp)->flags = DMAMAP_COULD_BOUNCE;
/*
* Attempt to add pages to our pool on a per-instance
@ -321,11 +338,11 @@ bounce_bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
error = 0;
}
bz->map_count++;
} else {
*mapp = NULL;
}
if (error == 0)
dmat->map_count++;
else
free(*mapp, M_DEVBUF);
CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
__func__, dmat, dmat->common.flags, error);
return (error);
@ -339,16 +356,20 @@ static int
bounce_bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
{
if (map != NULL && map != &nobounce_dmamap) {
if (STAILQ_FIRST(&map->bpages) != NULL) {
CTR3(KTR_BUSDMA, "%s: tag %p error %d",
__func__, dmat, EBUSY);
return (EBUSY);
}
if (dmat->bounce_zone)
dmat->bounce_zone->map_count--;
free(map, M_DEVBUF);
/* Check we are destroying the correct map type */
if ((map->flags & DMAMAP_FROM_DMAMEM) != 0)
panic("bounce_bus_dmamap_destroy: Invalid map freed\n");
if (STAILQ_FIRST(&map->bpages) != NULL) {
CTR3(KTR_BUSDMA, "%s: tag %p error %d", __func__, dmat, EBUSY);
return (EBUSY);
}
if (dmat->bounce_zone) {
KASSERT((map->flags & DMAMAP_COULD_BOUNCE) != 0,
("%s: Bounce zone when cannot bounce", __func__));
dmat->bounce_zone->map_count--;
}
free(map, M_DEVBUF);
dmat->map_count--;
CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat);
return (0);
@ -379,9 +400,6 @@ bounce_bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
else
mflags = M_WAITOK;
/* If we succeed, no mapping/bouncing will be required */
*mapp = NULL;
if (dmat->segments == NULL) {
dmat->segments = (bus_dma_segment_t *)malloc(
sizeof(bus_dma_segment_t) * dmat->common.nsegments,
@ -399,6 +417,18 @@ bounce_bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
else
attr = VM_MEMATTR_DEFAULT;
/*
* Create the map, but don't set the could bounce flag as
* this allocation should never bounce;
*/
*mapp = alloc_dmamap(mflags);
if (*mapp == NULL) {
CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
__func__, dmat, dmat->common.flags, ENOMEM);
return (ENOMEM);
}
(*mapp)->flags = DMAMAP_FROM_DMAMEM;
/*
* XXX:
* (dmat->alignment <= dmat->maxsize) is just a quick hack; the exact
@ -431,10 +461,12 @@ bounce_bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
if (*vaddr == NULL) {
CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
__func__, dmat, dmat->common.flags, ENOMEM);
free(*mapp, M_DEVBUF);
return (ENOMEM);
} else if (vtophys(*vaddr) & (dmat->common.alignment - 1)) {
printf("bus_dmamem_alloc failed to align memory properly.\n");
}
dmat->map_count++;
CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
__func__, dmat, dmat->common.flags, 0);
return (0);
@ -447,18 +479,21 @@ bounce_bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
static void
bounce_bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
{
/*
* dmamem does not need to be bounced, so the map should be
* NULL and the BUS_DMA_KMEM_ALLOC flag cleared if malloc()
* Check the map came from bounce_bus_dmamem_alloc, so the map
* should be NULL and the BUS_DMA_KMEM_ALLOC flag cleared if malloc()
* was used and set if kmem_alloc_contig() was used.
*/
if (map != NULL)
if ((map->flags & DMAMAP_FROM_DMAMEM) == 0)
panic("bus_dmamem_free: Invalid map freed\n");
if ((dmat->bounce_flags & BUS_DMA_KMEM_ALLOC) == 0)
free(vaddr, M_DEVBUF);
else
kmem_free(kernel_arena, (vm_offset_t)vaddr,
dmat->common.maxsize);
free(map, M_DEVBUF);
dmat->map_count--;
CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat,
dmat->bounce_flags);
}
@ -470,7 +505,7 @@ _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t buf,
bus_addr_t curaddr;
bus_size_t sgsize;
if ((map != &nobounce_dmamap && map->pagesneeded == 0)) {
if ((map->flags & DMAMAP_COULD_BOUNCE) != 0 && map->pagesneeded == 0) {
/*
* Count the number of bounce pages
* needed in order to complete this transfer
@ -499,13 +534,13 @@ _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap,
bus_addr_t paddr;
bus_size_t sg_len;
if ((map != &nobounce_dmamap && map->pagesneeded == 0)) {
if ((map->flags & DMAMAP_COULD_BOUNCE) != 0 && map->pagesneeded == 0) {
CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
"alignment= %d", dmat->common.lowaddr,
ptoa((vm_paddr_t)Maxmem),
dmat->common.boundary, dmat->common.alignment);
CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d",
map, &nobounce_dmamap, map->pagesneeded);
CTR2(KTR_BUSDMA, "map= %p, pagesneeded= %d", map,
map->pagesneeded);
/*
* Count the number of bounce pages
* needed in order to complete this transfer
@ -613,9 +648,6 @@ bounce_bus_dmamap_load_phys(bus_dma_tag_t dmat, bus_dmamap_t map,
bus_addr_t curaddr;
int error;
if (map == NULL)
map = &nobounce_dmamap;
if (segs == NULL)
segs = dmat->segments;
@ -666,9 +698,6 @@ bounce_bus_dmamap_load_buffer(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
vm_offset_t kvaddr, vaddr;
int error;
if (map == NULL)
map = &nobounce_dmamap;
if (segs == NULL)
segs = dmat->segments;
@ -728,7 +757,7 @@ bounce_bus_dmamap_waitok(bus_dma_tag_t dmat, bus_dmamap_t map,
struct memdesc *mem, bus_dmamap_callback_t *callback, void *callback_arg)
{
if (map == NULL)
if ((map->flags & DMAMAP_COULD_BOUNCE) == 0)
return;
map->mem = *mem;
map->dmat = dmat;
@ -754,7 +783,7 @@ bounce_bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
{
struct bounce_page *bpage;
if (map == NULL)
if ((map->flags & DMAMAP_COULD_BOUNCE) == 0)
return;
while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
@ -770,7 +799,7 @@ bounce_bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map,
struct bounce_page *bpage;
vm_offset_t datavaddr, tempvaddr;
if (map == NULL || (bpage = STAILQ_FIRST(&map->bpages)) == NULL) {
if ((bpage = STAILQ_FIRST(&map->bpages)) == NULL) {
/* Wait for any memory access to complete */
dsb(sy);
return;
@ -798,7 +827,6 @@ bounce_bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map,
bcopy((void *)datavaddr,
(void *)bpage->vaddr, bpage->datacount);
if (tempvaddr != 0)
pmap_quick_remove_page(tempvaddr);
bpage = STAILQ_NEXT(bpage, links);
@ -999,7 +1027,7 @@ add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
struct bounce_page *bpage;
KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag"));
KASSERT(map != NULL && map != &nobounce_dmamap,
KASSERT((map->flags & DMAMAP_COULD_BOUNCE) != 0,
("add_bounce_page: bad map %p", map));
bz = dmat->bounce_zone;