freebsd-skq/sys/dev/drm/drm_pci.c
2014-06-13 18:20:44 +00:00

130 lines
3.7 KiB
C

/*-
* Copyright 2003 Eric Anholt.
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/**
* \file drm_pci.h
* \brief PCI consistent, DMA-accessible memory allocation.
*
* \author Eric Anholt <anholt@FreeBSD.org>
*/
#include "dev/drm/drmP.h"
/**********************************************************************/
/** \name PCI memory */
/*@{*/
static void
drm_pci_busdma_callback(void *arg, bus_dma_segment_t *segs, int nsegs, int error)
{
drm_dma_handle_t *dmah = arg;
if (error != 0)
return;
KASSERT(nsegs == 1, ("drm_pci_busdma_callback: bad dma segment count"));
dmah->busaddr = segs[0].ds_addr;
}
/**
* \brief Allocate a physically contiguous DMA-accessible consistent
* memory block.
*/
drm_dma_handle_t *
drm_pci_alloc(struct drm_device *dev, size_t size,
size_t align, dma_addr_t maxaddr)
{
drm_dma_handle_t *dmah;
int ret;
/* Need power-of-two alignment, so fail the allocation if it isn't. */
if ((align & (align - 1)) != 0) {
DRM_ERROR("drm_pci_alloc with non-power-of-two alignment %d\n",
(int)align);
return NULL;
}
dmah = malloc(sizeof(drm_dma_handle_t), DRM_MEM_DMA, M_ZERO | M_NOWAIT);
if (dmah == NULL)
return NULL;
/* Make sure we aren't holding locks here */
mtx_assert(&dev->dev_lock, MA_NOTOWNED);
if (mtx_owned(&dev->dev_lock))
DRM_ERROR("called while holding dev_lock\n");
mtx_assert(&dev->dma_lock, MA_NOTOWNED);
if (mtx_owned(&dev->dma_lock))
DRM_ERROR("called while holding dma_lock\n");
ret = bus_dma_tag_create(NULL, align, 0, /* tag, align, boundary */
maxaddr, BUS_SPACE_MAXADDR, /* lowaddr, highaddr */
NULL, NULL, /* filtfunc, filtfuncargs */
size, 1, size, /* maxsize, nsegs, maxsegsize */
0, NULL, NULL, /* flags, lockfunc, lockfuncargs */
&dmah->tag);
if (ret != 0) {
free(dmah, DRM_MEM_DMA);
return NULL;
}
ret = bus_dmamem_alloc(dmah->tag, &dmah->vaddr,
BUS_DMA_WAITOK | BUS_DMA_ZERO | BUS_DMA_NOCACHE, &dmah->map);
if (ret != 0) {
bus_dma_tag_destroy(dmah->tag);
free(dmah, DRM_MEM_DMA);
return NULL;
}
ret = bus_dmamap_load(dmah->tag, dmah->map, dmah->vaddr, size,
drm_pci_busdma_callback, dmah, BUS_DMA_NOWAIT);
if (ret != 0) {
bus_dmamem_free(dmah->tag, dmah->vaddr, dmah->map);
bus_dma_tag_destroy(dmah->tag);
free(dmah, DRM_MEM_DMA);
return NULL;
}
return dmah;
}
/**
* \brief Free a DMA-accessible consistent memory block.
*/
void
drm_pci_free(struct drm_device *dev, drm_dma_handle_t *dmah)
{
if (dmah == NULL)
return;
bus_dmamap_unload(dmah->tag, dmah->map);
bus_dmamem_free(dmah->tag, dmah->vaddr, dmah->map);
bus_dma_tag_destroy(dmah->tag);
free(dmah, DRM_MEM_DMA);
}
/*@}*/