1 // SPDX-License-Identifier: GPL-2.0+
2 /* Copyright (C) 2015-2018 Broadcom */
5 * DOC: V3D GEM BO management support
7 * Compared to VC4 (V3D 2.x), V3D 3.3 introduces an MMU between the
8 * GPU and the bus, allowing us to use shmem objects for our storage
11 * Physically contiguous objects may still be imported to V3D, but the
12 * driver doesn't allocate physically contiguous objects on its own.
13 * Display engines requiring physically contiguous allocations should
14 * look into Mesa's "renderonly" support (as used by the Mesa pl111
15 * driver) for an example of how to integrate with V3D.
17 * Long term, we should support evicting pages from the MMU when under
18 * memory pressure (thus the v3d_bo_get_pages() refcounting), but
19 * that's not a high priority since our systems tend to not have swap.
22 #include <linux/dma-buf.h>
23 #include <linux/pfn_t.h>
26 #include "uapi/drm/v3d_drm.h"
28 /* Called DRM core on the last userspace/kernel unreference of the
31 void v3d_free_object(struct drm_gem_object *obj)
33 struct v3d_dev *v3d = to_v3d_dev(obj->dev);
34 struct v3d_bo *bo = to_v3d_bo(obj);
39 v3d_mmu_remove_ptes(bo);
41 mutex_lock(&v3d->bo_lock);
42 v3d->bo_stats.num_allocated--;
43 v3d->bo_stats.pages_allocated -= obj->size >> PAGE_SHIFT;
44 mutex_unlock(&v3d->bo_lock);
46 spin_lock(&v3d->mm_lock);
47 drm_mm_remove_node(&bo->node);
48 spin_unlock(&v3d->mm_lock);
50 /* GPU execution may have dirtied any pages in the BO. */
51 bo->base.pages_mark_dirty_on_put = true;
53 drm_gem_shmem_free(&bo->base);
56 static const struct drm_gem_object_funcs v3d_gem_funcs = {
57 .free = v3d_free_object,
58 .print_info = drm_gem_shmem_object_print_info,
59 .pin = drm_gem_shmem_object_pin,
60 .unpin = drm_gem_shmem_object_unpin,
61 .get_sg_table = drm_gem_shmem_object_get_sg_table,
62 .vmap = drm_gem_shmem_object_vmap,
63 .vunmap = drm_gem_shmem_object_vunmap,
64 .mmap = drm_gem_shmem_object_mmap,
65 .vm_ops = &drm_gem_shmem_vm_ops,
68 /* gem_create_object function for allocating a BO struct and doing
71 struct drm_gem_object *v3d_create_object(struct drm_device *dev, size_t size)
74 struct drm_gem_object *obj;
77 return ERR_PTR(-EINVAL);
79 bo = kzalloc(sizeof(*bo), GFP_KERNEL);
81 return ERR_PTR(-ENOMEM);
84 obj->funcs = &v3d_gem_funcs;
85 bo->base.map_wc = true;
86 INIT_LIST_HEAD(&bo->unref_head);
88 return &bo->base.base;
92 v3d_bo_create_finish(struct drm_gem_object *obj)
94 struct v3d_dev *v3d = to_v3d_dev(obj->dev);
95 struct v3d_bo *bo = to_v3d_bo(obj);
99 /* So far we pin the BO in the MMU for its lifetime, so use
100 * shmem's helper for getting a lifetime sgt.
102 sgt = drm_gem_shmem_get_pages_sgt(&bo->base);
106 spin_lock(&v3d->mm_lock);
107 /* Allocate the object's space in the GPU's page tables.
108 * Inserting PTEs will happen later, but the offset is for the
109 * lifetime of the BO.
111 ret = drm_mm_insert_node_generic(&v3d->mm, &bo->node,
112 obj->size >> PAGE_SHIFT,
113 GMP_GRANULARITY >> PAGE_SHIFT, 0, 0);
114 spin_unlock(&v3d->mm_lock);
118 /* Track stats for /debug/dri/n/bo_stats. */
119 mutex_lock(&v3d->bo_lock);
120 v3d->bo_stats.num_allocated++;
121 v3d->bo_stats.pages_allocated += obj->size >> PAGE_SHIFT;
122 mutex_unlock(&v3d->bo_lock);
124 v3d_mmu_insert_ptes(bo);
129 struct v3d_bo *v3d_bo_create(struct drm_device *dev, struct drm_file *file_priv,
130 size_t unaligned_size)
132 struct drm_gem_shmem_object *shmem_obj;
136 shmem_obj = drm_gem_shmem_create(dev, unaligned_size);
137 if (IS_ERR(shmem_obj))
138 return ERR_CAST(shmem_obj);
139 bo = to_v3d_bo(&shmem_obj->base);
142 ret = v3d_bo_create_finish(&shmem_obj->base);
149 drm_gem_shmem_free(shmem_obj);
153 struct drm_gem_object *
154 v3d_prime_import_sg_table(struct drm_device *dev,
155 struct dma_buf_attachment *attach,
156 struct sg_table *sgt)
158 struct drm_gem_object *obj;
161 obj = drm_gem_shmem_prime_import_sg_table(dev, attach, sgt);
165 ret = v3d_bo_create_finish(obj);
167 drm_gem_shmem_free(&to_v3d_bo(obj)->base);
174 void v3d_get_bo_vaddr(struct v3d_bo *bo)
176 struct drm_gem_shmem_object *obj = &bo->base;
178 bo->vaddr = vmap(obj->pages, obj->base.size >> PAGE_SHIFT, VM_MAP,
179 pgprot_writecombine(PAGE_KERNEL));
182 void v3d_put_bo_vaddr(struct v3d_bo *bo)
188 int v3d_create_bo_ioctl(struct drm_device *dev, void *data,
189 struct drm_file *file_priv)
191 struct drm_v3d_create_bo *args = data;
192 struct v3d_bo *bo = NULL;
195 if (args->flags != 0) {
196 DRM_INFO("unknown create_bo flags: %d\n", args->flags);
200 bo = v3d_bo_create(dev, file_priv, PAGE_ALIGN(args->size));
204 args->offset = bo->node.start << PAGE_SHIFT;
206 ret = drm_gem_handle_create(file_priv, &bo->base.base, &args->handle);
207 drm_gem_object_put(&bo->base.base);
212 int v3d_mmap_bo_ioctl(struct drm_device *dev, void *data,
213 struct drm_file *file_priv)
215 struct drm_v3d_mmap_bo *args = data;
216 struct drm_gem_object *gem_obj;
218 if (args->flags != 0) {
219 DRM_INFO("unknown mmap_bo flags: %d\n", args->flags);
223 gem_obj = drm_gem_object_lookup(file_priv, args->handle);
225 DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
229 args->offset = drm_vma_node_offset_addr(&gem_obj->vma_node);
230 drm_gem_object_put(gem_obj);
235 int v3d_get_bo_offset_ioctl(struct drm_device *dev, void *data,
236 struct drm_file *file_priv)
238 struct drm_v3d_get_bo_offset *args = data;
239 struct drm_gem_object *gem_obj;
242 gem_obj = drm_gem_object_lookup(file_priv, args->handle);
244 DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
247 bo = to_v3d_bo(gem_obj);
249 args->offset = bo->node.start << PAGE_SHIFT;
251 drm_gem_object_put(gem_obj);
256 v3d_wait_bo_ioctl(struct drm_device *dev, void *data,
257 struct drm_file *file_priv)
260 struct drm_v3d_wait_bo *args = data;
261 ktime_t start = ktime_get();
263 unsigned long timeout_jiffies =
264 nsecs_to_jiffies_timeout(args->timeout_ns);
269 ret = drm_gem_dma_resv_wait(file_priv, args->handle,
270 true, timeout_jiffies);
272 /* Decrement the user's timeout, in case we got interrupted
273 * such that the ioctl will be restarted.
275 delta_ns = ktime_to_ns(ktime_sub(ktime_get(), start));
276 if (delta_ns < args->timeout_ns)
277 args->timeout_ns -= delta_ns;
279 args->timeout_ns = 0;
281 /* Asked to wait beyond the jiffie/scheduler precision? */
282 if (ret == -ETIME && args->timeout_ns)