1/*
  2 * Copyright (c) 2015 MediaTek Inc.
  3 *
  4 * This program is free software; you can redistribute it and/or modify
  5 * it under the terms of the GNU General Public License version 2 as
  6 * published by the Free Software Foundation.
  7 *
  8 * This program is distributed in the hope that it will be useful,
  9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 11 * GNU General Public License for more details.
 12 */
 13
 14#include <drm/drmP.h>
 15#include <drm/drm_gem.h>
 16#include <linux/dma-buf.h>
 17
 18#include "mtk_drm_drv.h"
 19#include "mtk_drm_gem.h"
 20
 21static struct mtk_drm_gem_obj *mtk_drm_gem_init(struct drm_device *dev,
 22						unsigned long size)
 23{
 24	struct mtk_drm_gem_obj *mtk_gem_obj;
 25	int ret;
 26
 27	size = round_up(size, PAGE_SIZE);
 28
 29	mtk_gem_obj = kzalloc(sizeof(*mtk_gem_obj), GFP_KERNEL);
 30	if (!mtk_gem_obj)
 31		return ERR_PTR(-ENOMEM);
 32
 33	ret = drm_gem_object_init(dev, &mtk_gem_obj->base, size);
 34	if (ret < 0) {
 35		DRM_ERROR("failed to initialize gem object\n");
 36		kfree(mtk_gem_obj);
 37		return ERR_PTR(ret);
 38	}
 39
 40	return mtk_gem_obj;
 41}
 42
 43struct mtk_drm_gem_obj *mtk_drm_gem_create(struct drm_device *dev,
 44					   size_t size, bool alloc_kmap)
 45{
 46	struct mtk_drm_private *priv = dev->dev_private;
 47	struct mtk_drm_gem_obj *mtk_gem;
 48	struct drm_gem_object *obj;
 49	int ret;
 50
 51	mtk_gem = mtk_drm_gem_init(dev, size);
 52	if (IS_ERR(mtk_gem))
 53		return ERR_CAST(mtk_gem);
 54
 55	obj = &mtk_gem->base;
 56
 57	mtk_gem->dma_attrs = DMA_ATTR_WRITE_COMBINE;
 58
 59	if (!alloc_kmap)
 60		mtk_gem->dma_attrs |= DMA_ATTR_NO_KERNEL_MAPPING;
 61
 62	mtk_gem->cookie = dma_alloc_attrs(priv->dma_dev, obj->size,
 63					  &mtk_gem->dma_addr, GFP_KERNEL,
 64					  mtk_gem->dma_attrs);
 65	if (!mtk_gem->cookie) {
 66		DRM_ERROR("failed to allocate %zx byte dma buffer", obj->size);
 67		ret = -ENOMEM;
 68		goto err_gem_free;
 69	}
 70
 71	if (alloc_kmap)
 72		mtk_gem->kvaddr = mtk_gem->cookie;
 73
 74	DRM_DEBUG_DRIVER("cookie = %p dma_addr = %pad size = %zu\n",
 75			 mtk_gem->cookie, &mtk_gem->dma_addr,
 76			 size);
 77
 78	return mtk_gem;
 79
 80err_gem_free:
 81	drm_gem_object_release(obj);
 82	kfree(mtk_gem);
 83	return ERR_PTR(ret);
 84}
 85
 86void mtk_drm_gem_free_object(struct drm_gem_object *obj)
 87{
 88	struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
 89	struct mtk_drm_private *priv = obj->dev->dev_private;
 90
 91	if (mtk_gem->sg)
 92		drm_prime_gem_destroy(obj, mtk_gem->sg);
 93	else
 94		dma_free_attrs(priv->dma_dev, obj->size, mtk_gem->cookie,
 95			       mtk_gem->dma_addr, mtk_gem->dma_attrs);
 96
 97	/* release file pointer to gem object. */
 98	drm_gem_object_release(obj);
 99
100	kfree(mtk_gem);
101}
102
103int mtk_drm_gem_dumb_create(struct drm_file *file_priv, struct drm_device *dev,
104			    struct drm_mode_create_dumb *args)
105{
106	struct mtk_drm_gem_obj *mtk_gem;
107	int ret;
108
109	args->pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
110	args->size = args->pitch * args->height;
111
112	mtk_gem = mtk_drm_gem_create(dev, args->size, false);
113	if (IS_ERR(mtk_gem))
114		return PTR_ERR(mtk_gem);
115
116	/*
117	 * allocate a id of idr table where the obj is registered
118	 * and handle has the id what user can see.
119	 */
120	ret = drm_gem_handle_create(file_priv, &mtk_gem->base, &args->handle);
121	if (ret)
122		goto err_handle_create;
123
124	/* drop reference from allocate - handle holds it now. */
125	drm_gem_object_unreference_unlocked(&mtk_gem->base);
126
127	return 0;
128
129err_handle_create:
130	mtk_drm_gem_free_object(&mtk_gem->base);
131	return ret;
132}
133
134int mtk_drm_gem_dumb_map_offset(struct drm_file *file_priv,
135				struct drm_device *dev, uint32_t handle,
136				uint64_t *offset)
137{
138	struct drm_gem_object *obj;
139	int ret;
140
141	obj = drm_gem_object_lookup(file_priv, handle);
142	if (!obj) {
143		DRM_ERROR("failed to lookup gem object.\n");
144		return -EINVAL;
145	}
146
147	ret = drm_gem_create_mmap_offset(obj);
148	if (ret)
149		goto out;
150
151	*offset = drm_vma_node_offset_addr(&obj->vma_node);
152	DRM_DEBUG_KMS("offset = 0x%llx\n", *offset);
153
154out:
155	drm_gem_object_unreference_unlocked(obj);
156	return ret;
157}
158
159static int mtk_drm_gem_object_mmap(struct drm_gem_object *obj,
160				   struct vm_area_struct *vma)
161
162{
163	int ret;
164	struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
165	struct mtk_drm_private *priv = obj->dev->dev_private;
166
167	/*
168	 * dma_alloc_attrs() allocated a struct page table for mtk_gem, so clear
169	 * VM_PFNMAP flag that was set by drm_gem_mmap_obj()/drm_gem_mmap().
170	 */
171	vma->vm_flags &= ~VM_PFNMAP;
172	vma->vm_pgoff = 0;
173
174	ret = dma_mmap_attrs(priv->dma_dev, vma, mtk_gem->cookie,
175			     mtk_gem->dma_addr, obj->size, mtk_gem->dma_attrs);
176	if (ret)
177		drm_gem_vm_close(vma);
178
179	return ret;
180}
181
182int mtk_drm_gem_mmap_buf(struct drm_gem_object *obj, struct vm_area_struct *vma)
183{
184	int ret;
185
186	ret = drm_gem_mmap_obj(obj, obj->size, vma);
187	if (ret)
188		return ret;
189
190	return mtk_drm_gem_object_mmap(obj, vma);
191}
192
193int mtk_drm_gem_mmap(struct file *filp, struct vm_area_struct *vma)
194{
195	struct drm_gem_object *obj;
196	int ret;
197
198	ret = drm_gem_mmap(filp, vma);
199	if (ret)
200		return ret;
201
202	obj = vma->vm_private_data;
203
204	return mtk_drm_gem_object_mmap(obj, vma);
205}
206
207/*
208 * Allocate a sg_table for this GEM object.
209 * Note: Both the table's contents, and the sg_table itself must be freed by
210 *       the caller.
211 * Returns a pointer to the newly allocated sg_table, or an ERR_PTR() error.
212 */
213struct sg_table *mtk_gem_prime_get_sg_table(struct drm_gem_object *obj)
214{
215	struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
216	struct mtk_drm_private *priv = obj->dev->dev_private;
217	struct sg_table *sgt;
218	int ret;
219
220	sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
221	if (!sgt)
222		return ERR_PTR(-ENOMEM);
223
224	ret = dma_get_sgtable_attrs(priv->dma_dev, sgt, mtk_gem->cookie,
225				    mtk_gem->dma_addr, obj->size,
226				    mtk_gem->dma_attrs);
227	if (ret) {
228		DRM_ERROR("failed to allocate sgt, %d\n", ret);
229		kfree(sgt);
230		return ERR_PTR(ret);
231	}
232
233	return sgt;
234}
235
236struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev,
237			struct dma_buf_attachment *attach, struct sg_table *sg)
238{
239	struct mtk_drm_gem_obj *mtk_gem;
240	int ret;
241	struct scatterlist *s;
242	unsigned int i;
243	dma_addr_t expected;
244
245	mtk_gem = mtk_drm_gem_init(dev, attach->dmabuf->size);
246
247	if (IS_ERR(mtk_gem))
248		return ERR_PTR(PTR_ERR(mtk_gem));
249
250	expected = sg_dma_address(sg->sgl);
251	for_each_sg(sg->sgl, s, sg->nents, i) {
252		if (sg_dma_address(s) != expected) {
253			DRM_ERROR("sg_table is not contiguous");
254			ret = -EINVAL;
255			goto err_gem_free;
256		}
257		expected = sg_dma_address(s) + sg_dma_len(s);
258	}
259
260	mtk_gem->dma_addr = sg_dma_address(sg->sgl);
261	mtk_gem->sg = sg;
262
263	return &mtk_gem->base;
264
265err_gem_free:
266	kfree(mtk_gem);
267	return ERR_PTR(ret);
268}