diff options
author | Paul Cercueil <paul@crapouillou.net> | 2021-05-28 00:03:34 +0100 |
---|---|---|
committer | Paul Cercueil <paul@crapouillou.net> | 2021-05-28 09:47:53 +0100 |
commit | 162ba3bd9dce61889eb739adf2923811dcbeff94 (patch) | |
tree | 51042243cb6553794e3632d6f6af6ecb1b5bb07c /drivers/gpu/drm/drm_gem_cma_helper.c | |
parent | 71b970c8680732b3dec1f9506087ef56bd6a123d (diff) |
drm: Fix for GEM buffers with write-combine memory
The previous commit wrongly assumed that dma_mmap_wc() could be replaced
by pgprot_writecombine() + dma_mmap_pages(). It did work on my setup,
but did not work everywhere.
Use dma_mmap_wc() when the buffer has the write-combine cache attribute,
and dma_mmap_pages() when it has the non-coherent cache attribute.
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Reported-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Tested-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Fixes: cf8ccbc72d61 ("drm: Add support for GEM buffers backed by non-coherent memory")
Link: https://patchwork.freedesktop.org/patch/msgid/20210527230334.151947-1-paul@crapouillou.net
Diffstat (limited to 'drivers/gpu/drm/drm_gem_cma_helper.c')
-rw-r--r-- | drivers/gpu/drm/drm_gem_cma_helper.c | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/drivers/gpu/drm/drm_gem_cma_helper.c b/drivers/gpu/drm/drm_gem_cma_helper.c index 235c7a63da2b..4a24af2c5c43 100644 --- a/drivers/gpu/drm/drm_gem_cma_helper.c +++ b/drivers/gpu/drm/drm_gem_cma_helper.c @@ -514,13 +514,16 @@ int drm_gem_cma_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma) cma_obj = to_drm_gem_cma_obj(obj); - vma->vm_page_prot = vm_get_page_prot(vma->vm_flags); - if (!cma_obj->map_noncoherent) - vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot); + if (cma_obj->map_noncoherent) { + vma->vm_page_prot = vm_get_page_prot(vma->vm_flags); - ret = dma_mmap_pages(cma_obj->base.dev->dev, - vma, vma->vm_end - vma->vm_start, - virt_to_page(cma_obj->vaddr)); + ret = dma_mmap_pages(cma_obj->base.dev->dev, + vma, vma->vm_end - vma->vm_start, + virt_to_page(cma_obj->vaddr)); + } else { + ret = dma_mmap_wc(cma_obj->base.dev->dev, vma, cma_obj->vaddr, + cma_obj->paddr, vma->vm_end - vma->vm_start); + } if (ret) drm_gem_vm_close(vma); |