1 // SPDX-License-Identifier: GPL-2.0+ 2 /* Copyright (C) 2015-2018 Broadcom */ 3 4 /** 5 * DOC: V3D GEM BO management support 6 * 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 9 * instead of CMA. 10 * 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. 16 * 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. 20 */ 21 22 #include <linux/dma-buf.h> 23 #include <linux/pfn_t.h> 24 25 #include "v3d_drv.h" 26 #include "uapi/drm/v3d_drm.h" 27 28 /* Called DRM core on the last userspace/kernel unreference of the 29 * BO. 30 */ 31 void v3d_free_object(struct drm_gem_object *obj) 32 { 33 struct v3d_dev *v3d = to_v3d_dev(obj->dev); 34 struct v3d_bo *bo = to_v3d_bo(obj); 35 36 if (bo->vaddr) 37 v3d_put_bo_vaddr(bo); 38 39 v3d_mmu_remove_ptes(bo); 40 41 mutex_lock(&v3d->bo_lock); 42 v3d->bo_stats.num_allocated--; 43 v3d->bo_stats.pages_allocated -= obj->size >> V3D_MMU_PAGE_SHIFT; 44 mutex_unlock(&v3d->bo_lock); 45 46 spin_lock(&v3d->mm_lock); 47 drm_mm_remove_node(&bo->node); 48 spin_unlock(&v3d->mm_lock); 49 50 /* GPU execution may have dirtied any pages in the BO. */ 51 bo->base.pages_mark_dirty_on_put = true; 52 53 drm_gem_shmem_free(&bo->base); 54 } 55 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, 66 }; 67 68 /* gem_create_object function for allocating a BO struct and doing 69 * early setup. 70 */ 71 struct drm_gem_object *v3d_create_object(struct drm_device *dev, size_t size) 72 { 73 struct v3d_bo *bo; 74 struct drm_gem_object *obj; 75 76 if (size == 0) 77 return ERR_PTR(-EINVAL); 78 79 bo = kzalloc(sizeof(*bo), GFP_KERNEL); 80 if (!bo) 81 return ERR_PTR(-ENOMEM); 82 obj = &bo->base.base; 83 84 obj->funcs = &v3d_gem_funcs; 85 bo->base.map_wc = true; 86 INIT_LIST_HEAD(&bo->unref_head); 87 88 return &bo->base.base; 89 } 90 91 static int 92 v3d_bo_create_finish(struct drm_gem_object *obj) 93 { 94 struct v3d_dev *v3d = to_v3d_dev(obj->dev); 95 struct v3d_bo *bo = to_v3d_bo(obj); 96 struct sg_table *sgt; 97 int ret; 98 99 /* So far we pin the BO in the MMU for its lifetime, so use 100 * shmem's helper for getting a lifetime sgt. 101 */ 102 sgt = drm_gem_shmem_get_pages_sgt(&bo->base); 103 if (IS_ERR(sgt)) 104 return PTR_ERR(sgt); 105 106 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. 110 */ 111 ret = drm_mm_insert_node_generic(&v3d->mm, &bo->node, 112 obj->size >> V3D_MMU_PAGE_SHIFT, 113 GMP_GRANULARITY >> V3D_MMU_PAGE_SHIFT, 0, 0); 114 spin_unlock(&v3d->mm_lock); 115 if (ret) 116 return ret; 117 118 /* 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 >> V3D_MMU_PAGE_SHIFT; 122 mutex_unlock(&v3d->bo_lock); 123 124 v3d_mmu_insert_ptes(bo); 125 126 return 0; 127 } 128 129 struct v3d_bo *v3d_bo_create(struct drm_device *dev, struct drm_file *file_priv, 130 size_t unaligned_size) 131 { 132 struct drm_gem_shmem_object *shmem_obj; 133 struct v3d_bo *bo; 134 int ret; 135 136 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); 140 bo->vaddr = NULL; 141 142 ret = v3d_bo_create_finish(&shmem_obj->base); 143 if (ret) 144 goto free_obj; 145 146 return bo; 147 148 free_obj: 149 drm_gem_shmem_free(shmem_obj); 150 return ERR_PTR(ret); 151 } 152 153 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) 157 { 158 struct drm_gem_object *obj; 159 int ret; 160 161 obj = drm_gem_shmem_prime_import_sg_table(dev, attach, sgt); 162 if (IS_ERR(obj)) 163 return obj; 164 165 ret = v3d_bo_create_finish(obj); 166 if (ret) { 167 drm_gem_shmem_free(&to_v3d_bo(obj)->base); 168 return ERR_PTR(ret); 169 } 170 171 return obj; 172 } 173 174 void v3d_get_bo_vaddr(struct v3d_bo *bo) 175 { 176 struct drm_gem_shmem_object *obj = &bo->base; 177 178 bo->vaddr = vmap(obj->pages, obj->base.size >> PAGE_SHIFT, VM_MAP, 179 pgprot_writecombine(PAGE_KERNEL)); 180 } 181 182 void v3d_put_bo_vaddr(struct v3d_bo *bo) 183 { 184 vunmap(bo->vaddr); 185 bo->vaddr = NULL; 186 } 187 188 int v3d_create_bo_ioctl(struct drm_device *dev, void *data, 189 struct drm_file *file_priv) 190 { 191 struct drm_v3d_create_bo *args = data; 192 struct v3d_bo *bo = NULL; 193 int ret; 194 195 if (args->flags != 0) { 196 DRM_INFO("unknown create_bo flags: %d\n", args->flags); 197 return -EINVAL; 198 } 199 200 bo = v3d_bo_create(dev, file_priv, PAGE_ALIGN(args->size)); 201 if (IS_ERR(bo)) 202 return PTR_ERR(bo); 203 204 args->offset = bo->node.start << V3D_MMU_PAGE_SHIFT; 205 206 ret = drm_gem_handle_create(file_priv, &bo->base.base, &args->handle); 207 drm_gem_object_put(&bo->base.base); 208 209 return ret; 210 } 211 212 int v3d_mmap_bo_ioctl(struct drm_device *dev, void *data, 213 struct drm_file *file_priv) 214 { 215 struct drm_v3d_mmap_bo *args = data; 216 struct drm_gem_object *gem_obj; 217 218 if (args->flags != 0) { 219 DRM_INFO("unknown mmap_bo flags: %d\n", args->flags); 220 return -EINVAL; 221 } 222 223 gem_obj = drm_gem_object_lookup(file_priv, args->handle); 224 if (!gem_obj) { 225 DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle); 226 return -ENOENT; 227 } 228 229 args->offset = drm_vma_node_offset_addr(&gem_obj->vma_node); 230 drm_gem_object_put(gem_obj); 231 232 return 0; 233 } 234 235 int v3d_get_bo_offset_ioctl(struct drm_device *dev, void *data, 236 struct drm_file *file_priv) 237 { 238 struct drm_v3d_get_bo_offset *args = data; 239 struct drm_gem_object *gem_obj; 240 struct v3d_bo *bo; 241 242 gem_obj = drm_gem_object_lookup(file_priv, args->handle); 243 if (!gem_obj) { 244 DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle); 245 return -ENOENT; 246 } 247 bo = to_v3d_bo(gem_obj); 248 249 args->offset = bo->node.start << V3D_MMU_PAGE_SHIFT; 250 251 drm_gem_object_put(gem_obj); 252 return 0; 253 } 254 255 int 256 v3d_wait_bo_ioctl(struct drm_device *dev, void *data, 257 struct drm_file *file_priv) 258 { 259 int ret; 260 struct drm_v3d_wait_bo *args = data; 261 ktime_t start = ktime_get(); 262 u64 delta_ns; 263 unsigned long timeout_jiffies = 264 nsecs_to_jiffies_timeout(args->timeout_ns); 265 266 if (args->pad != 0) 267 return -EINVAL; 268 269 ret = drm_gem_dma_resv_wait(file_priv, args->handle, 270 true, timeout_jiffies); 271 272 /* Decrement the user's timeout, in case we got interrupted 273 * such that the ioctl will be restarted. 274 */ 275 delta_ns = ktime_to_ns(ktime_sub(ktime_get(), start)); 276 if (delta_ns < args->timeout_ns) 277 args->timeout_ns -= delta_ns; 278 else 279 args->timeout_ns = 0; 280 281 /* Asked to wait beyond the jiffie/scheduler precision? */ 282 if (ret == -ETIME && args->timeout_ns) 283 ret = -EAGAIN; 284 285 return ret; 286 } 287