[PATCH v2] drm/exynos: use DMA_ATTR_NO_KERNEL_MAPPING attribute
Inki Dae
inki.dae at samsung.com
Sun Dec 9 17:55:54 PST 2012
Changelog v2:
fix argument to dma_mmap_attr function.
- use pages instead of kvaddr because kvaddr is 0 with
DMA_ATTR_NO_KERNEL_MAPPING.
Changelog v1:
When gem allocation is requested, kernel space mapping isn't needed.
But if need, such as console framebuffer, the physical pages would be
mapped with kernel space though vmap function.
Signed-off-by: Inki Dae <inki.dae at samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park at samsung.com>
---
drivers/gpu/drm/exynos/exynos_drm_buf.c | 28 ++++++++++------------------
drivers/gpu/drm/exynos/exynos_drm_fbdev.c | 18 +++++++++++++++++-
drivers/gpu/drm/exynos/exynos_drm_gem.c | 2 +-
drivers/gpu/drm/exynos/exynos_drm_gem.h | 2 ++
4 files changed, 30 insertions(+), 20 deletions(-)
diff --git a/drivers/gpu/drm/exynos/exynos_drm_buf.c b/drivers/gpu/drm/exynos/exynos_drm_buf.c
index 72bf97b..2774e9b 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_buf.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_buf.c
@@ -35,6 +35,7 @@ static int lowlevel_buffer_allocate(struct drm_device *dev,
{
int ret = 0;
enum dma_attr attr = DMA_ATTR_FORCE_CONTIGUOUS;
+ unsigned int nr_pages;
DRM_DEBUG_KMS("%s\n", __FILE__);
@@ -49,40 +50,31 @@ static int lowlevel_buffer_allocate(struct drm_device *dev,
attr = DMA_ATTR_WRITE_COMBINE;
dma_set_attr(attr, &buf->dma_attrs);
+ dma_set_attr(DMA_ATTR_NO_KERNEL_MAPPING, &buf->dma_attrs);
- buf->kvaddr = dma_alloc_attrs(dev->dev, buf->size,
+ buf->pages = dma_alloc_attrs(dev->dev, buf->size,
&buf->dma_addr, GFP_KERNEL, &buf->dma_attrs);
- if (!buf->kvaddr) {
+ if (!buf->pages) {
DRM_ERROR("failed to allocate buffer.\n");
return -ENOMEM;
}
- buf->sgt = kzalloc(sizeof(struct sg_table), GFP_KERNEL);
+ nr_pages = buf->size >> PAGE_SHIFT;
+ buf->sgt = drm_prime_pages_to_sg(buf->pages, nr_pages);
if (!buf->sgt) {
- DRM_ERROR("failed to allocate sg table.\n");
+ DRM_ERROR("failed to get sg table.\n");
ret = -ENOMEM;
goto err_free_attrs;
}
- ret = dma_get_sgtable(dev->dev, buf->sgt, buf->kvaddr, buf->dma_addr,
- buf->size);
- if (ret < 0) {
- DRM_ERROR("failed to get sgtable.\n");
- goto err_free_sgt;
- }
-
- DRM_DEBUG_KMS("vaddr(0x%lx), dma_addr(0x%lx), size(0x%lx)\n",
- (unsigned long)buf->kvaddr,
+ DRM_DEBUG_KMS("dma_addr(0x%lx), size(0x%lx)\n",
(unsigned long)buf->dma_addr,
buf->size);
return ret;
-err_free_sgt:
- kfree(buf->sgt);
- buf->sgt = NULL;
err_free_attrs:
- dma_free_attrs(dev->dev, buf->size, buf->kvaddr,
+ dma_free_attrs(dev->dev, buf->size, buf->pages,
(dma_addr_t)buf->dma_addr, &buf->dma_attrs);
buf->dma_addr = (dma_addr_t)NULL;
@@ -109,7 +101,7 @@ static void lowlevel_buffer_deallocate(struct drm_device *dev,
kfree(buf->sgt);
buf->sgt = NULL;
- dma_free_attrs(dev->dev, buf->size, buf->kvaddr,
+ dma_free_attrs(dev->dev, buf->size, buf->pages,
(dma_addr_t)buf->dma_addr, &buf->dma_attrs);
buf->dma_addr = (dma_addr_t)NULL;
}
diff --git a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
index 885ef23..f433eb7 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
@@ -65,7 +65,7 @@ static int exynos_drm_fb_mmap(struct fb_info *info,
if (vm_size > buffer->size)
return -EINVAL;
- ret = dma_mmap_attrs(helper->dev->dev, vma, buffer->kvaddr,
+ ret = dma_mmap_attrs(helper->dev->dev, vma, buffer->pages,
buffer->dma_addr, buffer->size, &buffer->dma_attrs);
if (ret < 0) {
DRM_ERROR("failed to mmap.\n");
@@ -109,6 +109,17 @@ static int exynos_drm_fbdev_update(struct drm_fb_helper *helper,
return -EFAULT;
}
+ /* map pages with kernel virtual space. */
+ if (!buffer->kvaddr) {
+ unsigned int nr_pages = buffer->size >> PAGE_SHIFT;
+ buffer->kvaddr = vmap(buffer->pages, nr_pages, VM_MAP,
+ pgprot_writecombine(PAGE_KERNEL));
+ if (!buffer->kvaddr) {
+ DRM_ERROR("failed to map pages to kernel space.\n");
+ return -EIO;
+ }
+ }
+
/* buffer count to framebuffer always is 1 at booting time. */
exynos_drm_fb_set_buf_cnt(fb, 1);
@@ -305,8 +316,13 @@ err_init:
static void exynos_drm_fbdev_destroy(struct drm_device *dev,
struct drm_fb_helper *fb_helper)
{
+ struct exynos_drm_fbdev *exynos_fbd = to_exynos_fbdev(fb_helper);
+ struct exynos_drm_gem_obj *exynos_gem_obj = exynos_fbd->exynos_gem_obj;
struct drm_framebuffer *fb;
+ if (exynos_gem_obj->buffer->kvaddr)
+ vunmap(exynos_gem_obj->buffer->kvaddr);
+
/* release drm framebuffer and real buffer */
if (fb_helper->fb && fb_helper->fb->funcs) {
fb = fb_helper->fb;
diff --git a/drivers/gpu/drm/exynos/exynos_drm_gem.c b/drivers/gpu/drm/exynos/exynos_drm_gem.c
index 9922724..d48183e 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_gem.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_gem.c
@@ -400,7 +400,7 @@ static int exynos_drm_gem_mmap_buffer(struct file *filp,
if (vm_size > buffer->size)
return -EINVAL;
- ret = dma_mmap_attrs(drm_dev->dev, vma, buffer->kvaddr,
+ ret = dma_mmap_attrs(drm_dev->dev, vma, buffer->pages,
buffer->dma_addr, buffer->size,
&buffer->dma_attrs);
if (ret < 0) {
diff --git a/drivers/gpu/drm/exynos/exynos_drm_gem.h b/drivers/gpu/drm/exynos/exynos_drm_gem.h
index d3ea106..f11f2af 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_gem.h
+++ b/drivers/gpu/drm/exynos/exynos_drm_gem.h
@@ -40,6 +40,7 @@
* - this address could be physical address without IOMMU and
* device address with IOMMU.
* @write: whether pages will be written to by the caller.
+ * @pages: Array of backing pages.
* @sgt: sg table to transfer page data.
* @size: size of allocated memory region.
* @pfnmap: indicate whether memory region from userptr is mmaped with
@@ -51,6 +52,7 @@ struct exynos_drm_gem_buf {
dma_addr_t dma_addr;
struct dma_attrs dma_attrs;
unsigned int write;
+ struct page **pages;
struct sg_table *sgt;
unsigned long size;
bool pfnmap;
--
1.7.4.1
More information about the dri-devel
mailing list