1 /* 2 * psb GEM interface 3 * 4 * Copyright (c) 2011, Intel Corporation. 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms and conditions of the GNU General Public License, 8 * version 2, as published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 13 * more details. 14 * 15 * You should have received a copy of the GNU General Public License along with 16 * this program; if not, write to the Free Software Foundation, Inc., 17 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Authors: Alan Cox 20 * 21 * TODO: 22 * - we need to work out if the MMU is relevant (eg for 23 * accelerated operations on a GEM object) 24 */ 25 26 #include <drm/drmP.h> 27 #include <drm/drm.h> 28 #include <drm/gma_drm.h> 29 #include "psb_drv.h" 30 31 int psb_gem_init_object(struct drm_gem_object *obj) 32 { 33 return -EINVAL; 34 } 35 36 void psb_gem_free_object(struct drm_gem_object *obj) 37 { 38 struct gtt_range *gtt = container_of(obj, struct gtt_range, gem); 39 40 /* Remove the list map if one is present */ 41 if (obj->map_list.map) 42 drm_gem_free_mmap_offset(obj); 43 drm_gem_object_release(obj); 44 45 /* This must occur last as it frees up the memory of the GEM object */ 46 psb_gtt_free_range(obj->dev, gtt); 47 } 48 49 int psb_gem_get_aperture(struct drm_device *dev, void *data, 50 struct drm_file *file) 51 { 52 return -EINVAL; 53 } 54 55 /** 56 * psb_gem_dumb_map_gtt - buffer mapping for dumb interface 57 * @file: our drm client file 58 * @dev: drm device 59 * @handle: GEM handle to the object (from dumb_create) 60 * 61 * Do the necessary setup to allow the mapping of the frame buffer 62 * into user memory. We don't have to do much here at the moment. 63 */ 64 int psb_gem_dumb_map_gtt(struct drm_file *file, struct drm_device *dev, 65 uint32_t handle, uint64_t *offset) 66 { 67 int ret = 0; 68 struct drm_gem_object *obj; 69 70 if (!(dev->driver->driver_features & DRIVER_GEM)) 71 return -ENODEV; 72 73 mutex_lock(&dev->struct_mutex); 74 75 /* GEM does all our handle to object mapping */ 76 obj = drm_gem_object_lookup(dev, file, handle); 77 if (obj == NULL) { 78 ret = -ENOENT; 79 goto unlock; 80 } 81 /* What validation is needed here ? */ 82 83 /* Make it mmapable */ 84 if (!obj->map_list.map) { 85 ret = drm_gem_create_mmap_offset(obj); 86 if (ret) 87 goto out; 88 } 89 /* GEM should really work out the hash offsets for us */ 90 *offset = (u64)obj->map_list.hash.key << PAGE_SHIFT; 91 out: 92 drm_gem_object_unreference(obj); 93 unlock: 94 mutex_unlock(&dev->struct_mutex); 95 return ret; 96 } 97 98 /** 99 * psb_gem_create - create a mappable object 100 * @file: the DRM file of the client 101 * @dev: our device 102 * @size: the size requested 103 * @handlep: returned handle (opaque number) 104 * 105 * Create a GEM object, fill in the boilerplate and attach a handle to 106 * it so that userspace can speak about it. This does the core work 107 * for the various methods that do/will create GEM objects for things 108 */ 109 static int psb_gem_create(struct drm_file *file, 110 struct drm_device *dev, uint64_t size, uint32_t *handlep) 111 { 112 struct gtt_range *r; 113 int ret; 114 u32 handle; 115 116 size = roundup(size, PAGE_SIZE); 117 118 /* Allocate our object - for now a direct gtt range which is not 119 stolen memory backed */ 120 r = psb_gtt_alloc_range(dev, size, "gem", 0); 121 if (r == NULL) { 122 dev_err(dev->dev, "no memory for %lld byte GEM object\n", size); 123 return -ENOSPC; 124 } 125 /* Initialize the extra goodies GEM needs to do all the hard work */ 126 if (drm_gem_object_init(dev, &r->gem, size) != 0) { 127 psb_gtt_free_range(dev, r); 128 /* GEM doesn't give an error code so use -ENOMEM */ 129 dev_err(dev->dev, "GEM init failed for %lld\n", size); 130 return -ENOMEM; 131 } 132 /* Limit the object to 32bit mappings */ 133 mapping_set_gfp_mask(r->gem.filp->f_mapping, GFP_KERNEL | __GFP_DMA32); 134 /* Give the object a handle so we can carry it more easily */ 135 ret = drm_gem_handle_create(file, &r->gem, &handle); 136 if (ret) { 137 dev_err(dev->dev, "GEM handle failed for %p, %lld\n", 138 &r->gem, size); 139 drm_gem_object_release(&r->gem); 140 psb_gtt_free_range(dev, r); 141 return ret; 142 } 143 /* We have the initial and handle reference but need only one now */ 144 drm_gem_object_unreference(&r->gem); 145 *handlep = handle; 146 return 0; 147 } 148 149 /** 150 * psb_gem_dumb_create - create a dumb buffer 151 * @drm_file: our client file 152 * @dev: our device 153 * @args: the requested arguments copied from userspace 154 * 155 * Allocate a buffer suitable for use for a frame buffer of the 156 * form described by user space. Give userspace a handle by which 157 * to reference it. 158 */ 159 int psb_gem_dumb_create(struct drm_file *file, struct drm_device *dev, 160 struct drm_mode_create_dumb *args) 161 { 162 args->pitch = ALIGN(args->width * ((args->bpp + 7) / 8), 64); 163 args->size = args->pitch * args->height; 164 return psb_gem_create(file, dev, args->size, &args->handle); 165 } 166 167 /** 168 * psb_gem_dumb_destroy - destroy a dumb buffer 169 * @file: client file 170 * @dev: our DRM device 171 * @handle: the object handle 172 * 173 * Destroy a handle that was created via psb_gem_dumb_create, at least 174 * we hope it was created that way. i915 seems to assume the caller 175 * does the checking but that might be worth review ! FIXME 176 */ 177 int psb_gem_dumb_destroy(struct drm_file *file, struct drm_device *dev, 178 uint32_t handle) 179 { 180 /* No special work needed, drop the reference and see what falls out */ 181 return drm_gem_handle_delete(file, handle); 182 } 183 184 /** 185 * psb_gem_fault - pagefault handler for GEM objects 186 * @vma: the VMA of the GEM object 187 * @vmf: fault detail 188 * 189 * Invoked when a fault occurs on an mmap of a GEM managed area. GEM 190 * does most of the work for us including the actual map/unmap calls 191 * but we need to do the actual page work. 192 * 193 * This code eventually needs to handle faulting objects in and out 194 * of the GTT and repacking it when we run out of space. We can put 195 * that off for now and for our simple uses 196 * 197 * The VMA was set up by GEM. In doing so it also ensured that the 198 * vma->vm_private_data points to the GEM object that is backing this 199 * mapping. 200 */ 201 int psb_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 202 { 203 struct drm_gem_object *obj; 204 struct gtt_range *r; 205 int ret; 206 unsigned long pfn; 207 pgoff_t page_offset; 208 struct drm_device *dev; 209 struct drm_psb_private *dev_priv; 210 211 obj = vma->vm_private_data; /* GEM object */ 212 dev = obj->dev; 213 dev_priv = dev->dev_private; 214 215 r = container_of(obj, struct gtt_range, gem); /* Get the gtt range */ 216 217 /* Make sure we don't parallel update on a fault, nor move or remove 218 something from beneath our feet */ 219 mutex_lock(&dev->struct_mutex); 220 221 /* For now the mmap pins the object and it stays pinned. As things 222 stand that will do us no harm */ 223 if (r->mmapping == 0) { 224 ret = psb_gtt_pin(r); 225 if (ret < 0) { 226 dev_err(dev->dev, "gma500: pin failed: %d\n", ret); 227 goto fail; 228 } 229 r->mmapping = 1; 230 } 231 232 /* Page relative to the VMA start - we must calculate this ourselves 233 because vmf->pgoff is the fake GEM offset */ 234 page_offset = ((unsigned long) vmf->virtual_address - vma->vm_start) 235 >> PAGE_SHIFT; 236 237 /* CPU view of the page, don't go via the GART for CPU writes */ 238 if (r->stolen) 239 pfn = (dev_priv->stolen_base + r->offset) >> PAGE_SHIFT; 240 else 241 pfn = page_to_pfn(r->pages[page_offset]); 242 ret = vm_insert_pfn(vma, (unsigned long)vmf->virtual_address, pfn); 243 244 fail: 245 mutex_unlock(&dev->struct_mutex); 246 switch (ret) { 247 case 0: 248 case -ERESTARTSYS: 249 case -EINTR: 250 return VM_FAULT_NOPAGE; 251 case -ENOMEM: 252 return VM_FAULT_OOM; 253 default: 254 return VM_FAULT_SIGBUS; 255 } 256 } 257 258 static int psb_gem_create_stolen(struct drm_file *file, struct drm_device *dev, 259 int size, u32 *handle) 260 { 261 struct gtt_range *gtt = psb_gtt_alloc_range(dev, size, "gem", 1); 262 if (gtt == NULL) 263 return -ENOMEM; 264 if (drm_gem_private_object_init(dev, >t->gem, size) != 0) 265 goto free_gtt; 266 if (drm_gem_handle_create(file, >t->gem, handle) == 0) 267 return 0; 268 free_gtt: 269 psb_gtt_free_range(dev, gtt); 270 return -ENOMEM; 271 } 272 273 /* 274 * GEM interfaces for our specific client 275 */ 276 int psb_gem_create_ioctl(struct drm_device *dev, void *data, 277 struct drm_file *file) 278 { 279 struct drm_psb_gem_create *args = data; 280 int ret; 281 if (args->flags & GMA_GEM_CREATE_STOLEN) { 282 ret = psb_gem_create_stolen(file, dev, args->size, 283 &args->handle); 284 if (ret == 0) 285 return 0; 286 /* Fall throguh */ 287 args->flags &= ~GMA_GEM_CREATE_STOLEN; 288 } 289 return psb_gem_create(file, dev, args->size, &args->handle); 290 } 291 292 int psb_gem_mmap_ioctl(struct drm_device *dev, void *data, 293 struct drm_file *file) 294 { 295 struct drm_psb_gem_mmap *args = data; 296 return dev->driver->dumb_map_offset(file, dev, 297 args->handle, &args->offset); 298 } 299 300