1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
3 
4 #include <linux/err.h>
5 #include <linux/slab.h>
6 #include <linux/dma-buf.h>
7 #include <linux/dma-mapping.h>
8 
9 #include <drm/panfrost_drm.h>
10 #include "panfrost_device.h"
11 #include "panfrost_gem.h"
12 #include "panfrost_mmu.h"
13 
14 /* Called DRM core on the last userspace/kernel unreference of the
15  * BO.
16  */
17 static void panfrost_gem_free_object(struct drm_gem_object *obj)
18 {
19 	struct panfrost_gem_object *bo = to_panfrost_bo(obj);
20 	struct panfrost_device *pfdev = obj->dev->dev_private;
21 
22 	panfrost_mmu_unmap(bo);
23 
24 	spin_lock(&pfdev->mm_lock);
25 	drm_mm_remove_node(&bo->node);
26 	spin_unlock(&pfdev->mm_lock);
27 
28 	drm_gem_shmem_free_object(obj);
29 }
30 
31 static const struct drm_gem_object_funcs panfrost_gem_funcs = {
32 	.free = panfrost_gem_free_object,
33 	.print_info = drm_gem_shmem_print_info,
34 	.pin = drm_gem_shmem_pin,
35 	.unpin = drm_gem_shmem_unpin,
36 	.get_sg_table = drm_gem_shmem_get_sg_table,
37 	.vmap = drm_gem_shmem_vmap,
38 	.vunmap = drm_gem_shmem_vunmap,
39 	.vm_ops = &drm_gem_shmem_vm_ops,
40 };
41 
42 /**
43  * panfrost_gem_create_object - Implementation of driver->gem_create_object.
44  * @dev: DRM device
45  * @size: Size in bytes of the memory the object will reference
46  *
47  * This lets the GEM helpers allocate object structs for us, and keep
48  * our BO stats correct.
49  */
50 struct drm_gem_object *panfrost_gem_create_object(struct drm_device *dev, size_t size)
51 {
52 	int ret;
53 	struct panfrost_device *pfdev = dev->dev_private;
54 	struct panfrost_gem_object *obj;
55 
56 	obj = kzalloc(sizeof(*obj), GFP_KERNEL);
57 	if (!obj)
58 		return NULL;
59 
60 	obj->base.base.funcs = &panfrost_gem_funcs;
61 
62 	spin_lock(&pfdev->mm_lock);
63 	ret = drm_mm_insert_node(&pfdev->mm, &obj->node,
64 				 roundup(size, PAGE_SIZE) >> PAGE_SHIFT);
65 	spin_unlock(&pfdev->mm_lock);
66 	if (ret)
67 		goto free_obj;
68 
69 	return &obj->base.base;
70 
71 free_obj:
72 	kfree(obj);
73 	return ERR_PTR(ret);
74 }
75 
76 struct drm_gem_object *
77 panfrost_gem_prime_import_sg_table(struct drm_device *dev,
78 				   struct dma_buf_attachment *attach,
79 				   struct sg_table *sgt)
80 {
81 	struct drm_gem_object *obj;
82 	struct panfrost_gem_object *pobj;
83 
84 	obj = drm_gem_shmem_prime_import_sg_table(dev, attach, sgt);
85 	if (IS_ERR(obj))
86 		return ERR_CAST(obj);
87 
88 	pobj = to_panfrost_bo(obj);
89 
90 	obj->resv = attach->dmabuf->resv;
91 
92 	panfrost_mmu_map(pobj);
93 
94 	return obj;
95 }
96