blob: ac74d1bc67bfc885e740e6adc809a0bd5c8d2b1d [file] [log] [blame]
/*
* drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c
*
* Copyright (C) 2011 Texas Instruments
* Author: Rob Clark <rob.clark@linaro.org>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "omap_drv.h"
#include <linux/dma-buf.h>
static struct sg_table *omap_gem_map_dma_buf(
struct dma_buf_attachment *attachment,
enum dma_data_direction dir)
{
struct drm_gem_object *obj = attachment->dmabuf->priv;
struct sg_table *sg;
dma_addr_t paddr;
int ret;
sg = kzalloc(sizeof(*sg), GFP_KERNEL);
if (!sg)
return ERR_PTR(-ENOMEM);
/* camera, etc, need physically contiguous.. but we need a
* better way to know this..
*/
ret = omap_gem_get_paddr(obj, &paddr, true);
if (ret)
goto out;
ret = sg_alloc_table(sg, 1, GFP_KERNEL);
if (ret)
goto out;
sg_init_table(sg->sgl, 1);
sg_dma_len(sg->sgl) = obj->size;
sg_set_page(sg->sgl, pfn_to_page(PFN_DOWN(paddr)), obj->size, 0);
sg_dma_address(sg->sgl) = paddr;
/* this should be after _get_paddr() to ensure we have pages attached */
omap_gem_dma_sync(obj, dir);
return sg;
out:
kfree(sg);
return ERR_PTR(ret);
}
static void omap_gem_unmap_dma_buf(struct dma_buf_attachment *attachment,
struct sg_table *sg, enum dma_data_direction dir)
{
struct drm_gem_object *obj = attachment->dmabuf->priv;
omap_gem_put_paddr(obj);
sg_free_table(sg);
kfree(sg);
}
static void omap_gem_dmabuf_release(struct dma_buf *buffer)
{
struct drm_gem_object *obj = buffer->priv;
/* release reference that was taken when dmabuf was exported
* in omap_gem_prime_set()..
*/
drm_gem_object_unreference_unlocked(obj);
}
static int omap_gem_dmabuf_begin_cpu_access(struct dma_buf *buffer,
size_t start, size_t len, enum dma_data_direction dir)
{
struct drm_gem_object *obj = buffer->priv;
struct page **pages;
if (omap_gem_flags(obj) & OMAP_BO_TILED) {
/* TODO we would need to pin at least part of the buffer to
* get de-tiled view. For now just reject it.
*/
return -ENOMEM;
}
/* make sure we have the pages: */
return omap_gem_get_pages(obj, &pages, true);
}
static void omap_gem_dmabuf_end_cpu_access(struct dma_buf *buffer,
size_t start, size_t len, enum dma_data_direction dir)
{
struct drm_gem_object *obj = buffer->priv;
omap_gem_put_pages(obj);
}
static void *omap_gem_dmabuf_kmap_atomic(struct dma_buf *buffer,
unsigned long page_num)
{
struct drm_gem_object *obj = buffer->priv;
struct page **pages;
omap_gem_get_pages(obj, &pages, false);
omap_gem_cpu_sync(obj, page_num);
return kmap_atomic(pages[page_num]);
}
static void omap_gem_dmabuf_kunmap_atomic(struct dma_buf *buffer,
unsigned long page_num, void *addr)
{
kunmap_atomic(addr);
}
static void *omap_gem_dmabuf_kmap(struct dma_buf *buffer,
unsigned long page_num)
{
struct drm_gem_object *obj = buffer->priv;
struct page **pages;
omap_gem_get_pages(obj, &pages, false);
omap_gem_cpu_sync(obj, page_num);
return kmap(pages[page_num]);
}
static void omap_gem_dmabuf_kunmap(struct dma_buf *buffer,
unsigned long page_num, void *addr)
{
struct drm_gem_object *obj = buffer->priv;
struct page **pages;
omap_gem_get_pages(obj, &pages, false);
kunmap(pages[page_num]);
}
/*
* TODO maybe we can split up drm_gem_mmap to avoid duplicating
* some here.. or at least have a drm_dmabuf_mmap helper.
*/
static int omap_gem_dmabuf_mmap(struct dma_buf *buffer,
struct vm_area_struct *vma)
{
struct drm_gem_object *obj = buffer->priv;
int ret = 0;
if (WARN_ON(!obj->filp))
return -EINVAL;
/* Check for valid size. */
if (omap_gem_mmap_size(obj) < vma->vm_end - vma->vm_start) {
ret = -EINVAL;
goto out_unlock;
}
if (!obj->dev->driver->gem_vm_ops) {
ret = -EINVAL;
goto out_unlock;
}
vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
vma->vm_ops = obj->dev->driver->gem_vm_ops;
vma->vm_private_data = obj;
vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
/* Take a ref for this mapping of the object, so that the fault
* handler can dereference the mmap offset's pointer to the object.
* This reference is cleaned up by the corresponding vm_close
* (which should happen whether the vma was created by this call, or
* by a vm_open due to mremap or partial unmap or whatever).
*/
vma->vm_ops->open(vma);
out_unlock:
return omap_gem_mmap_obj(obj, vma);
}
struct dma_buf_ops omap_dmabuf_ops = {
.map_dma_buf = omap_gem_map_dma_buf,
.unmap_dma_buf = omap_gem_unmap_dma_buf,
.release = omap_gem_dmabuf_release,
.begin_cpu_access = omap_gem_dmabuf_begin_cpu_access,
.end_cpu_access = omap_gem_dmabuf_end_cpu_access,
.kmap_atomic = omap_gem_dmabuf_kmap_atomic,
.kunmap_atomic = omap_gem_dmabuf_kunmap_atomic,
.kmap = omap_gem_dmabuf_kmap,
.kunmap = omap_gem_dmabuf_kunmap,
.mmap = omap_gem_dmabuf_mmap,
};
struct dma_buf *omap_gem_prime_export(struct drm_device *dev,
struct drm_gem_object *obj, int flags)
{
return dma_buf_export(obj, &omap_dmabuf_ops, obj->size, flags);
}
struct drm_gem_object *omap_gem_prime_import(struct drm_device *dev,
struct dma_buf *buffer)
{
struct drm_gem_object *obj;
/* is this one of own objects? */
if (buffer->ops == &omap_dmabuf_ops) {
obj = buffer->priv;
/* is it from our device? */
if (obj->dev == dev) {
/*
* Importing dmabuf exported from out own gem increases
* refcount on gem itself instead of f_count of dmabuf.
*/
drm_gem_object_reference(obj);
dma_buf_put(buffer);
return obj;
}
}
/*
* TODO add support for importing buffers from other devices..
* for now we don't need this but would be nice to add eventually
*/
return ERR_PTR(-EINVAL);
}