xref: /linux/drivers/gpu/drm/panfrost/panfrost_gem.c (revision 72251fac062c0b4fe98670ec9e3db3f0702c50ae)
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 	if (bo->sgts) {
23 		int i;
24 		int n_sgt = bo->base.base.size / SZ_2M;
25 
26 		for (i = 0; i < n_sgt; i++) {
27 			if (bo->sgts[i].sgl) {
28 				dma_unmap_sg(pfdev->dev, bo->sgts[i].sgl,
29 					     bo->sgts[i].nents, DMA_BIDIRECTIONAL);
30 				sg_free_table(&bo->sgts[i]);
31 			}
32 		}
33 		kfree(bo->sgts);
34 	}
35 
36 	mutex_lock(&pfdev->shrinker_lock);
37 	if (!list_empty(&bo->base.madv_list))
38 		list_del(&bo->base.madv_list);
39 	mutex_unlock(&pfdev->shrinker_lock);
40 
41 	drm_gem_shmem_free_object(obj);
42 }
43 
44 static int panfrost_gem_open(struct drm_gem_object *obj, struct drm_file *file_priv)
45 {
46 	int ret;
47 	size_t size = obj->size;
48 	u64 align;
49 	struct panfrost_gem_object *bo = to_panfrost_bo(obj);
50 	struct panfrost_device *pfdev = obj->dev->dev_private;
51 	unsigned long color = bo->noexec ? PANFROST_BO_NOEXEC : 0;
52 
53 	/*
54 	 * Executable buffers cannot cross a 16MB boundary as the program
55 	 * counter is 24-bits. We assume executable buffers will be less than
56 	 * 16MB and aligning executable buffers to their size will avoid
57 	 * crossing a 16MB boundary.
58 	 */
59 	if (!bo->noexec)
60 		align = size >> PAGE_SHIFT;
61 	else
62 		align = size >= SZ_2M ? SZ_2M >> PAGE_SHIFT : 0;
63 
64 	spin_lock(&pfdev->mm_lock);
65 	ret = drm_mm_insert_node_generic(&pfdev->mm, &bo->node,
66 					 size >> PAGE_SHIFT, align, color, 0);
67 	if (ret)
68 		goto out;
69 
70 	if (!bo->is_heap) {
71 		ret = panfrost_mmu_map(bo);
72 		if (ret)
73 			drm_mm_remove_node(&bo->node);
74 	}
75 out:
76 	spin_unlock(&pfdev->mm_lock);
77 	return ret;
78 }
79 
80 static void panfrost_gem_close(struct drm_gem_object *obj, struct drm_file *file_priv)
81 {
82 	struct panfrost_gem_object *bo = to_panfrost_bo(obj);
83 	struct panfrost_device *pfdev = obj->dev->dev_private;
84 
85 	if (bo->is_mapped)
86 		panfrost_mmu_unmap(bo);
87 
88 	spin_lock(&pfdev->mm_lock);
89 	if (drm_mm_node_allocated(&bo->node))
90 		drm_mm_remove_node(&bo->node);
91 	spin_unlock(&pfdev->mm_lock);
92 }
93 
94 static int panfrost_gem_pin(struct drm_gem_object *obj)
95 {
96 	if (to_panfrost_bo(obj)->is_heap)
97 		return -EINVAL;
98 
99 	return drm_gem_shmem_pin(obj);
100 }
101 
102 static const struct drm_gem_object_funcs panfrost_gem_funcs = {
103 	.free = panfrost_gem_free_object,
104 	.open = panfrost_gem_open,
105 	.close = panfrost_gem_close,
106 	.print_info = drm_gem_shmem_print_info,
107 	.pin = panfrost_gem_pin,
108 	.unpin = drm_gem_shmem_unpin,
109 	.get_sg_table = drm_gem_shmem_get_sg_table,
110 	.vmap = drm_gem_shmem_vmap,
111 	.vunmap = drm_gem_shmem_vunmap,
112 	.vm_ops = &drm_gem_shmem_vm_ops,
113 };
114 
115 /**
116  * panfrost_gem_create_object - Implementation of driver->gem_create_object.
117  * @dev: DRM device
118  * @size: Size in bytes of the memory the object will reference
119  *
120  * This lets the GEM helpers allocate object structs for us, and keep
121  * our BO stats correct.
122  */
123 struct drm_gem_object *panfrost_gem_create_object(struct drm_device *dev, size_t size)
124 {
125 	struct panfrost_gem_object *obj;
126 
127 	obj = kzalloc(sizeof(*obj), GFP_KERNEL);
128 	if (!obj)
129 		return NULL;
130 
131 	obj->base.base.funcs = &panfrost_gem_funcs;
132 
133 	return &obj->base.base;
134 }
135 
136 struct panfrost_gem_object *
137 panfrost_gem_create_with_handle(struct drm_file *file_priv,
138 				struct drm_device *dev, size_t size,
139 				u32 flags,
140 				uint32_t *handle)
141 {
142 	int ret;
143 	struct drm_gem_shmem_object *shmem;
144 	struct panfrost_gem_object *bo;
145 
146 	/* Round up heap allocations to 2MB to keep fault handling simple */
147 	if (flags & PANFROST_BO_HEAP)
148 		size = roundup(size, SZ_2M);
149 
150 	shmem = drm_gem_shmem_create(dev, size);
151 	if (IS_ERR(shmem))
152 		return ERR_CAST(shmem);
153 
154 	bo = to_panfrost_bo(&shmem->base);
155 	bo->noexec = !!(flags & PANFROST_BO_NOEXEC);
156 	bo->is_heap = !!(flags & PANFROST_BO_HEAP);
157 
158 	/*
159 	 * Allocate an id of idr table where the obj is registered
160 	 * and handle has the id what user can see.
161 	 */
162 	ret = drm_gem_handle_create(file_priv, &shmem->base, handle);
163 	/* drop reference from allocate - handle holds it now. */
164 	drm_gem_object_put_unlocked(&shmem->base);
165 	if (ret)
166 		return ERR_PTR(ret);
167 
168 	return bo;
169 }
170 
171 struct drm_gem_object *
172 panfrost_gem_prime_import_sg_table(struct drm_device *dev,
173 				   struct dma_buf_attachment *attach,
174 				   struct sg_table *sgt)
175 {
176 	struct drm_gem_object *obj;
177 	struct panfrost_gem_object *bo;
178 
179 	obj = drm_gem_shmem_prime_import_sg_table(dev, attach, sgt);
180 	if (IS_ERR(obj))
181 		return ERR_CAST(obj);
182 
183 	bo = to_panfrost_bo(obj);
184 	bo->noexec = true;
185 
186 	return obj;
187 }
188