drm/exynos: add exynos drm specific fb_mmap function
Changelog v3:
Passing the actual buffer size instead of vm_size to dma_mmap_attrs.
Changelog v2:
Extracting the private data from fb_info structure to obtain the exynos
gem buffer structure. Now, dma address is obtained from the exynos gem
buffer structure and not from smem_start. Also calling dma_mmap_attrs
(instead of dma_mmap_writecombine) with the same attributes used
during allocation.
Changelog v1:
This patch adds a exynos drm specific implementation of fb_mmap
which supports mapping a non-contiguous buffer to user space.
This new function does not assume that the frame buffer is contiguous
and calls dma_mmap_writecombine for mapping the buffer to user space.
dma_mmap_writecombine will be able to map a contiguous buffer as well
as non-contig buffer depending on whether an IOMMU mapping is created
for drm or not.
Signed-off-by: Prathyush K <prathyush.k@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
diff --git a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
index e7466c4..151c4c9 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
@@ -46,8 +46,38 @@
struct exynos_drm_gem_obj *exynos_gem_obj;
};
+static int exynos_drm_fb_mmap(struct fb_info *info,
+ struct vm_area_struct *vma)
+{
+ struct drm_fb_helper *helper = info->par;
+ struct exynos_drm_fbdev *exynos_fbd = to_exynos_fbdev(helper);
+ struct exynos_drm_gem_obj *exynos_gem_obj = exynos_fbd->exynos_gem_obj;
+ struct exynos_drm_gem_buf *buffer = exynos_gem_obj->buffer;
+ unsigned long vm_size;
+ int ret;
+
+ DRM_DEBUG_KMS("%s\n", __func__);
+
+ vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
+
+ vm_size = vma->vm_end - vma->vm_start;
+
+ if (vm_size > buffer->size)
+ return -EINVAL;
+
+ ret = dma_mmap_attrs(helper->dev->dev, vma, buffer->kvaddr,
+ buffer->dma_addr, buffer->size, &buffer->dma_attrs);
+ if (ret < 0) {
+ DRM_ERROR("failed to mmap.\n");
+ return ret;
+ }
+
+ return 0;
+}
+
static struct fb_ops exynos_drm_fb_ops = {
.owner = THIS_MODULE,
+ .fb_mmap = exynos_drm_fb_mmap,
.fb_fillrect = cfb_fillrect,
.fb_copyarea = cfb_copyarea,
.fb_imageblit = cfb_imageblit,