1 files changed, 58 insertions, 12 deletions

diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
index 259b7b0de1d2..b04a3c2b111e 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
@@ -1,20 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright (c) 2015 MediaTek Inc.
- *
- * 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.
  */
 
-#include <drm/drmP.h>
-#include <drm/drm_gem.h>
 #include <linux/dma-buf.h>
 
+#include <drm/drm.h>
+#include <drm/drm_device.h>
+#include <drm/drm_gem.h>
+#include <drm/drm_prime.h>
+
 #include "mtk_drm_drv.h"
 #include "mtk_drm_gem.h"
 
@@ -144,7 +139,6 @@ static int mtk_drm_gem_object_mmap(struct drm_gem_object *obj,
 	 * VM_PFNMAP flag that was set by drm_gem_mmap_obj()/drm_gem_mmap().
 	 */
 	vma->vm_flags &= ~VM_PFNMAP;
-	vma->vm_pgoff = 0;
 
 	ret = dma_mmap_attrs(priv->dma_dev, vma, mtk_gem->cookie,
 			     mtk_gem->dma_addr, obj->size, mtk_gem->dma_attrs);
@@ -176,6 +170,12 @@ int mtk_drm_gem_mmap(struct file *filp, struct vm_area_struct *vma)
 
 	obj = vma->vm_private_data;
 
+	/*
+	 * Set vm_pgoff (used as a fake buffer offset by DRM) to 0 and map the
+	 * whole buffer from the start.
+	 */
+	vma->vm_pgoff = 0;
+
 	return mtk_drm_gem_object_mmap(obj, vma);
 }
 
@@ -241,3 +241,49 @@ err_gem_free:
 	kfree(mtk_gem);
 	return ERR_PTR(ret);
 }
+
+void *mtk_drm_gem_prime_vmap(struct drm_gem_object *obj)
+{
+	struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
+	struct sg_table *sgt;
+	struct sg_page_iter iter;
+	unsigned int npages;
+	unsigned int i = 0;
+
+	if (mtk_gem->kvaddr)
+		return mtk_gem->kvaddr;
+
+	sgt = mtk_gem_prime_get_sg_table(obj);
+	if (IS_ERR(sgt))
+		return NULL;
+
+	npages = obj->size >> PAGE_SHIFT;
+	mtk_gem->pages = kcalloc(npages, sizeof(*mtk_gem->pages), GFP_KERNEL);
+	if (!mtk_gem->pages)
+		goto out;
+
+	for_each_sg_page(sgt->sgl, &iter, sgt->orig_nents, 0) {
+		mtk_gem->pages[i++] = sg_page_iter_page(&iter);
+		if (i > npages)
+			break;
+	}
+	mtk_gem->kvaddr = vmap(mtk_gem->pages, npages, VM_MAP,
+			       pgprot_writecombine(PAGE_KERNEL));
+
+out:
+	kfree(sgt);
+
+	return mtk_gem->kvaddr;
+}
+
+void mtk_drm_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
+{
+	struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
+
+	if (!mtk_gem->pages)
+		return;
+
+	vunmap(vaddr);
+	mtk_gem->kvaddr = 0;
+	kfree(mtk_gem->pages);
+}