xref: /linux/drivers/gpu/drm/panthor/panthor_gem.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0 or MIT
2 /* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
3 /* Copyright 2023 Collabora ltd. */
4 
5 #include <linux/dma-buf.h>
6 #include <linux/dma-mapping.h>
7 #include <linux/err.h>
8 #include <linux/slab.h>
9 
10 #include <drm/panthor_drm.h>
11 
12 #include "panthor_device.h"
13 #include "panthor_gem.h"
14 #include "panthor_mmu.h"
15 
16 static void panthor_gem_free_object(struct drm_gem_object *obj)
17 {
18 	struct panthor_gem_object *bo = to_panthor_bo(obj);
19 	struct drm_gem_object *vm_root_gem = bo->exclusive_vm_root_gem;
20 
21 	drm_gem_free_mmap_offset(&bo->base.base);
22 	mutex_destroy(&bo->gpuva_list_lock);
23 	drm_gem_shmem_free(&bo->base);
24 	drm_gem_object_put(vm_root_gem);
25 }
26 
27 /**
28  * panthor_kernel_bo_destroy() - Destroy a kernel buffer object
29  * @bo: Kernel buffer object to destroy. If NULL or an ERR_PTR(), the destruction
30  * is skipped.
31  */
32 void panthor_kernel_bo_destroy(struct panthor_kernel_bo *bo)
33 {
34 	struct panthor_vm *vm;
35 	int ret;
36 
37 	if (IS_ERR_OR_NULL(bo))
38 		return;
39 
40 	vm = bo->vm;
41 	panthor_kernel_bo_vunmap(bo);
42 
43 	if (drm_WARN_ON(bo->obj->dev,
44 			to_panthor_bo(bo->obj)->exclusive_vm_root_gem != panthor_vm_root_gem(vm)))
45 		goto out_free_bo;
46 
47 	ret = panthor_vm_unmap_range(vm, bo->va_node.start, bo->va_node.size);
48 	if (ret)
49 		goto out_free_bo;
50 
51 	panthor_vm_free_va(vm, &bo->va_node);
52 	drm_gem_object_put(bo->obj);
53 
54 out_free_bo:
55 	panthor_vm_put(vm);
56 	kfree(bo);
57 }
58 
59 /**
60  * panthor_kernel_bo_create() - Create and map a GEM object to a VM
61  * @ptdev: Device.
62  * @vm: VM to map the GEM to. If NULL, the kernel object is not GPU mapped.
63  * @size: Size of the buffer object.
64  * @bo_flags: Combination of drm_panthor_bo_flags flags.
65  * @vm_map_flags: Combination of drm_panthor_vm_bind_op_flags (only those
66  * that are related to map operations).
67  * @gpu_va: GPU address assigned when mapping to the VM.
68  * If gpu_va == PANTHOR_VM_KERNEL_AUTO_VA, the virtual address will be
69  * automatically allocated.
70  *
71  * Return: A valid pointer in case of success, an ERR_PTR() otherwise.
72  */
73 struct panthor_kernel_bo *
74 panthor_kernel_bo_create(struct panthor_device *ptdev, struct panthor_vm *vm,
75 			 size_t size, u32 bo_flags, u32 vm_map_flags,
76 			 u64 gpu_va)
77 {
78 	struct drm_gem_shmem_object *obj;
79 	struct panthor_kernel_bo *kbo;
80 	struct panthor_gem_object *bo;
81 	int ret;
82 
83 	if (drm_WARN_ON(&ptdev->base, !vm))
84 		return ERR_PTR(-EINVAL);
85 
86 	kbo = kzalloc(sizeof(*kbo), GFP_KERNEL);
87 	if (!kbo)
88 		return ERR_PTR(-ENOMEM);
89 
90 	obj = drm_gem_shmem_create(&ptdev->base, size);
91 	if (IS_ERR(obj)) {
92 		ret = PTR_ERR(obj);
93 		goto err_free_bo;
94 	}
95 
96 	bo = to_panthor_bo(&obj->base);
97 	kbo->obj = &obj->base;
98 	bo->flags = bo_flags;
99 
100 	/* The system and GPU MMU page size might differ, which becomes a
101 	 * problem for FW sections that need to be mapped at explicit address
102 	 * since our PAGE_SIZE alignment might cover a VA range that's
103 	 * expected to be used for another section.
104 	 * Make sure we never map more than we need.
105 	 */
106 	size = ALIGN(size, panthor_vm_page_size(vm));
107 	ret = panthor_vm_alloc_va(vm, gpu_va, size, &kbo->va_node);
108 	if (ret)
109 		goto err_put_obj;
110 
111 	ret = panthor_vm_map_bo_range(vm, bo, 0, size, kbo->va_node.start, vm_map_flags);
112 	if (ret)
113 		goto err_free_va;
114 
115 	kbo->vm = panthor_vm_get(vm);
116 	bo->exclusive_vm_root_gem = panthor_vm_root_gem(vm);
117 	drm_gem_object_get(bo->exclusive_vm_root_gem);
118 	bo->base.base.resv = bo->exclusive_vm_root_gem->resv;
119 	return kbo;
120 
121 err_free_va:
122 	panthor_vm_free_va(vm, &kbo->va_node);
123 
124 err_put_obj:
125 	drm_gem_object_put(&obj->base);
126 
127 err_free_bo:
128 	kfree(kbo);
129 	return ERR_PTR(ret);
130 }
131 
132 static int panthor_gem_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
133 {
134 	struct panthor_gem_object *bo = to_panthor_bo(obj);
135 
136 	/* Don't allow mmap on objects that have the NO_MMAP flag set. */
137 	if (bo->flags & DRM_PANTHOR_BO_NO_MMAP)
138 		return -EINVAL;
139 
140 	return drm_gem_shmem_object_mmap(obj, vma);
141 }
142 
143 static struct dma_buf *
144 panthor_gem_prime_export(struct drm_gem_object *obj, int flags)
145 {
146 	/* We can't export GEMs that have an exclusive VM. */
147 	if (to_panthor_bo(obj)->exclusive_vm_root_gem)
148 		return ERR_PTR(-EINVAL);
149 
150 	return drm_gem_prime_export(obj, flags);
151 }
152 
153 static const struct drm_gem_object_funcs panthor_gem_funcs = {
154 	.free = panthor_gem_free_object,
155 	.print_info = drm_gem_shmem_object_print_info,
156 	.pin = drm_gem_shmem_object_pin,
157 	.unpin = drm_gem_shmem_object_unpin,
158 	.get_sg_table = drm_gem_shmem_object_get_sg_table,
159 	.vmap = drm_gem_shmem_object_vmap,
160 	.vunmap = drm_gem_shmem_object_vunmap,
161 	.mmap = panthor_gem_mmap,
162 	.export = panthor_gem_prime_export,
163 	.vm_ops = &drm_gem_shmem_vm_ops,
164 };
165 
166 /**
167  * panthor_gem_create_object - Implementation of driver->gem_create_object.
168  * @ddev: DRM device
169  * @size: Size in bytes of the memory the object will reference
170  *
171  * This lets the GEM helpers allocate object structs for us, and keep
172  * our BO stats correct.
173  */
174 struct drm_gem_object *panthor_gem_create_object(struct drm_device *ddev, size_t size)
175 {
176 	struct panthor_device *ptdev = container_of(ddev, struct panthor_device, base);
177 	struct panthor_gem_object *obj;
178 
179 	obj = kzalloc(sizeof(*obj), GFP_KERNEL);
180 	if (!obj)
181 		return ERR_PTR(-ENOMEM);
182 
183 	obj->base.base.funcs = &panthor_gem_funcs;
184 	obj->base.map_wc = !ptdev->coherent;
185 	mutex_init(&obj->gpuva_list_lock);
186 	drm_gem_gpuva_set_lock(&obj->base.base, &obj->gpuva_list_lock);
187 
188 	return &obj->base.base;
189 }
190 
191 /**
192  * panthor_gem_create_with_handle() - Create a GEM object and attach it to a handle.
193  * @file: DRM file.
194  * @ddev: DRM device.
195  * @exclusive_vm: Exclusive VM. Not NULL if the GEM object can't be shared.
196  * @size: Size of the GEM object to allocate.
197  * @flags: Combination of drm_panthor_bo_flags flags.
198  * @handle: Pointer holding the handle pointing to the new GEM object.
199  *
200  * Return: Zero on success
201  */
202 int
203 panthor_gem_create_with_handle(struct drm_file *file,
204 			       struct drm_device *ddev,
205 			       struct panthor_vm *exclusive_vm,
206 			       u64 *size, u32 flags, u32 *handle)
207 {
208 	int ret;
209 	struct drm_gem_shmem_object *shmem;
210 	struct panthor_gem_object *bo;
211 
212 	shmem = drm_gem_shmem_create(ddev, *size);
213 	if (IS_ERR(shmem))
214 		return PTR_ERR(shmem);
215 
216 	bo = to_panthor_bo(&shmem->base);
217 	bo->flags = flags;
218 
219 	if (exclusive_vm) {
220 		bo->exclusive_vm_root_gem = panthor_vm_root_gem(exclusive_vm);
221 		drm_gem_object_get(bo->exclusive_vm_root_gem);
222 		bo->base.base.resv = bo->exclusive_vm_root_gem->resv;
223 	}
224 
225 	/*
226 	 * Allocate an id of idr table where the obj is registered
227 	 * and handle has the id what user can see.
228 	 */
229 	ret = drm_gem_handle_create(file, &shmem->base, handle);
230 	if (!ret)
231 		*size = bo->base.base.size;
232 
233 	/* drop reference from allocate - handle holds it now. */
234 	drm_gem_object_put(&shmem->base);
235 
236 	return ret;
237 }
238