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 --- drivers/gpu/drm/exynos/exynos_drm_fbdev.c | 16 ++++++++++++++++ 1 files changed, 16 insertions(+), 0 deletions(-)
diff --git a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c index d5586cc..b53e638 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c +++ b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c @@ -46,8 +46,24 @@ struct exynos_drm_fbdev { struct exynos_drm_gem_obj *exynos_gem_obj; };
+static int exynos_drm_fb_mmap(struct fb_info *info, + struct vm_area_struct *vma) +{ + if ((vma->vm_end - vma->vm_start) > info->fix.smem_len) + return -EINVAL; + + vma->vm_pgoff = 0; + vma->vm_flags |= VM_IO | VM_RESERVED; + if (dma_mmap_writecombine(info->device, vma, info->screen_base, + info->fix.smem_start, vma->vm_end - vma->vm_start)) + return -EAGAIN; + + 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,